WO2010111073A1 - Medical device for assessing intravascular blood volume and technique for using the same - Google Patents
Medical device for assessing intravascular blood volume and technique for using the same Download PDFInfo
- Publication number
- WO2010111073A1 WO2010111073A1 PCT/US2010/027508 US2010027508W WO2010111073A1 WO 2010111073 A1 WO2010111073 A1 WO 2010111073A1 US 2010027508 W US2010027508 W US 2010027508W WO 2010111073 A1 WO2010111073 A1 WO 2010111073A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- patient
- variability
- information
- patient parameter
- monitor
- Prior art date
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/145—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue
- A61B5/1455—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue using optical sensors, e.g. spectral photometrical oximeters
- A61B5/14551—Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissue using optical sensors, e.g. spectral photometrical oximeters for measuring blood gases
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/02—Detecting, measuring or recording pulse, heart rate, blood pressure or blood flow; Combined pulse/heart-rate/blood pressure determination; Evaluating a cardiovascular condition not otherwise provided for, e.g. using combinations of techniques provided for in this group with electrocardiography or electroauscultation; Heart catheters for measuring blood pressure
- A61B5/02028—Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
- A61B5/00—Measuring for diagnostic purposes; Identification of persons
- A61B5/48—Other medical applications
- A61B5/4836—Diagnosis combined with treatment in closed-loop systems or methods
- A61B5/4839—Diagnosis combined with treatment in closed-loop systems or methods combined with drug delivery
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/0051—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes with alarm devices
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M16/00—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes
- A61M16/021—Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes operated by electrical means
- A61M16/022—Control means therefor
- A61M16/024—Control means therefor including calculation means, e.g. using a processor
- A61M16/026—Control means therefor including calculation means, e.g. using a processor specially adapted for predicting, e.g. for determining an information representative of a flow limitation during a ventilation cycle by using a root square technique or a regression analysis
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61M—DEVICES FOR INTRODUCING MEDIA INTO, OR ONTO, THE BODY; DEVICES FOR TRANSDUCING BODY MEDIA OR FOR TAKING MEDIA FROM THE BODY; DEVICES FOR PRODUCING OR ENDING SLEEP OR STUPOR
- A61M2230/00—Measuring parameters of the user
- A61M2230/20—Blood composition characteristics
- A61M2230/205—Blood composition characteristics partial oxygen pressure (P-O2)
Definitions
- the present disclosure relates generally to a method and system for monitoring physiological parameters of a patient. Specifically, embodiments of the present invention relate to more accurate estimation of intravascular blood volume and fluid responsiveness by adjusting pulse oximetry waveform measurements to account for variations in respiratory parameters and/or other patient parameters.
- intravascular volume blood fluid volume
- Variations from normal fluid volume in the blood may indicate a change in clinical condition or an injury.
- hypovolemia is a state of decreased intravascular volume that may be associated with dehydration.
- Correct clinical assessment of hypovolemia is complex. More specifically, intravascular volume is difficult to estimate, particularly in critically ill patients. Without an accurate assessment of a patient's intravascular volume, it is difficult to predict whether a patient will respond to fluid therapy (e.g., a blood or fluid infusion) with an improvement in clinical condition, such as an increase in stroke volume and cardiac output. Accordingly, accurate assessments of intravascular volume may assist a clinician in determining whether a patient will be responsive to fluid therapy.
- fluid therapy e.g., a blood or fluid infusion
- indicators such as the systolic blood pressure variation, pulse pressure variation, or stroke volume variation may be used to estimate intravascular volume and determine whether a patient is likely to be fluid responsive.
- these measurements tend to be invasive.
- a physician may insert an invasive arterial line.
- FIG. 1 is a block diagram of a ventilation system for determining intravascular blood volume in accordance with an embodiment
- FIG. 2 is a block diagram of a patient monitor that may be used in conjunction with the ventilation system of FIG. 1 in accordance with an embodiment
- FIG. 3 is a block diagram of a method illustrating an embodiment
- FIG. 4 is a plethysniographic waveform illustrating an embodiment
- FIG. 5 is a block diagram of a closed-loop ventilation system for administering a fluid therapy in accordance with an embodiment.
- monitoring physiological parameters may be complex. For example, certain physiological characteristics of the patient may be influenced by the medical treatment being provided. Pn embodiments, a ventilator may control a patient's breathing rate along with the type and amount of gases inhaled. Because respiration affects the delivery of oxygen from the lungs into the blood, changes in ventilation parameters and/or patient lung conditions may result in changes to hemodynamic parameters, such as pulse pressure and blood oxygenation.
- the variability in a waveform representative of a patient's blood oxygen levels may be used to estimate a patient's intravascular volume.
- Blood oxygen levels may be monitored with a non-invasive, optical pulse oximetry sensor that transmits two or more wavelengths of light, most commonly red and near infrared wavelengths, through a patient's tissue and that photoelectrical ⁇ detects the absorption and/or scattering of the transmitted light in such tissue.
- a non-invasive, optical pulse oximetry sensor that transmits two or more wavelengths of light, most commonly red and near infrared wavelengths, through a patient's tissue and that photoelectrical ⁇ detects the absorption and/or scattering of the transmitted light in such tissue.
- the use of pulse oximetry to estimate intravascular volume and fluid responsiveness in ventilated patients provides the ease of use of a noninvasive, rather than invasive, sensor.
- blood oxygen measurements may be affected by other clinical conditions, such as respiratory parameters.
- the plethysmographic waveform signal may be sensitive to respiratory parameters, such as respiration rate, tidal volume, end tidal carbon dioxide concentration, or positive end-expiratory pressure, which may be controlled by particular settings on a ventilator.
- the plethysmographic waveform signal may be sensitive to tissue or blood constituent concentration, for example, a tissue water fraction or a partial pressure of carbon dioxide in the tissue.
- the plethysmographic waveform signal may have certain patient-to-patient variability based on age, weight, gender, and clinical condition.
- the plethysmographic waveform signal may be corrected or adjusted to provide a more accurate estimate of intravascular volume.
- a clinician may use the estimate of intravascular volume to make determinations about a patient's clinical condition, such as the likelihood that the patient will respond to fluid therapy.
- the adjustment may correct for certain physiological conditions that may influence the plethysmographic waveform and that may either mask or exaggerate the plethysmographic waveform variability. For example, in the case of a ventilated patient with a controlled respiration rate, the patient's blood oxygen saturation, may be higher relative to a patient who is not receiving breathing assistance.
- a ventilated patient with generally higher respiration rate may have greater peak-to-peak variability in a plethysmographic waveform, which in turn would result in a higher calculated variability value.
- higher variability values e.g., greater than 15% variability
- an artificially high variability value may mask a patient's true fluid responsiveness.
- the resulting plethysmographic waveform variability value may be more accurate. Accordingly, a clinician may be able to make more informed decisions about whether the patient may benefit from fluid therapy. In addition, the clinician may be able to assess changes in blood volume more rapidly and may be able to intervene to provide therapy to the patient at an earlier time point.
- a closed-loop system is provided in which the corrected plethysmographic waveform variability is used to estimate the intravascular volume and determine the fluid responsiveness of a patient.
- a closed-loop controller may control delivery of fluid therapy if the estimate of intravascular volume is associated with hypovolemia, which, may indicate that the patient will be responsive to fluid therapy.
- Embodiments provided herein are directed to medical devices for assessing intravascular volume based on respiratory or other patient parameters. Suitable devices may be incorporated into a respiratory system 10, shown in FIG. 1, or any other patient monitoring system.
- the respiratory system 10 may include a tracheal tube 12, such as an endotracheal tube, that is inserted into a patient 14 to deliver gases to and from the patient's lungs.
- the respiratory system 10 may also include a respiratory circuit 16 connecting the tracheal tube 12 to a ventilator 18.
- the ventilator 18 may be a positive pressure ventilator, such as those available from Nellcor Puritan Bennett LLC.
- the system 10 may also include a pulse oximetry sensor 20 for generating a plethysmography waveform signal representative of a patient's blood oxygen levels.
- the pulse oximetry sensor 20 may be in communication with a monitor 22 configured to receive the plethysmography waveform signal and estimate the patient's intravascular volume and/or fluid responsiveness.
- the monitoring functions of the monitor 22 may be incorporated into a single device that also performs the functions of ventilator 18.
- the plethysmographic waveform variability may be corrected by adjusting for respiratory parameters controlled by the ventilator 18.
- the ventilator 18 may include a controller for controlling respiration rate, tidal volume, flow rate, pressure, peak airway pressure, ratio of expiration to inspiration time, fraction of inspired oxygen (i.e., the percentage of oxygen in the gas mixture), inspired pressure increases or decreases over each breath (e.g., positive end-expiratory pressure), and any other respiratory parameter.
- Any suitable respiratory parameter controlled by the ventilator 18 may be used to adjust an estimate of intravascular volume, as discussed in more detail below.
- the respiratory system 10 may also include any number or combination of additional sensors for providing information related to patient parameters that may be used to correct or adjust the estimate of the patient's intravascular volume and/or fluid responsiveness.
- suitable sensors may include sensors for determining tissue hydration, tissue constituents, blood constituents, blood pressure, heart rate, patient temperature, or tissue impedance.
- sensors may also include sensors for determining the presence or concentration of biomarkers, including sensors for circulating biomarkers related to cardiac stress and function (e.g., troponin or cholesterol) and/or biomarkers associated with lung function (e.g., surfactant protein D).
- Suitable sensors for providing information about additional patient parameters may be optical, electrical, chemical, or biological sensors.
- a carbon dioxide sensor or tissue water fraction sensor may direct two or more wavelengths of light, most commonly near infrared wavelengths between about 1,000 nm to about 2,500 nm, into a sample, e.g., a gas sample or a tissue sample.
- Other sensors may include electrical sensors, such as electrical impedance sensors that may sense a voltage drop between two electrodes that are applied to a patient's tissue.
- Chemical sensors may include colorimetric chemical sensors, such as colorimetric sensors for detection of carbon dioxide.
- a chemical sensor for carbon dioxide may include an indicator solution containing hydroxyl ions or amine residues that react chemically with carbon dioxide to form a carbonate and/or a bicarbonate or carbamate moiety, such as those discussed in co-pending U.S. Application No. 11/526,393 by Ostrowski et al., filed on September 25, 2006, the specification of which is incorporated by reference in its entirety herein for all purposes. This reaction may ultimately result in a color change that may be optically detected.
- Biological sensors may include enzymatic sensors for detecting a color or fluorescence change produced by enzymatic reactions or by antibody/ligand binding.
- surfactant protein D may be detected by an enzyme-linked immunosorbent assay available from Cell Sciences (Canton, MA).
- FIG. 1 shows a carbon dioxide sensor 24 that may be associated with the respiratory circuit 16 and an aquametry sensor 26 that may be applied to an appropriate tissue location on the patient 14.
- carbon dioxide sensor 24 and aquametiy sensor 26 are merely illustrative of sensor types that may be used in conjunction with the respiratory system 10.
- the carbon dioxide sensor 24 may be disposed along the respiratory circuit 16 (e.g., within a tube or connector of the respiratory circuit 16) or associated with the respiratory circuit 16. Ln addition, the carbon dioxide sensor 24 may be applied to a patient's tissue for determining partial pressure of carbon dioxide by optically interrogating the tissue.
- Carbon dioxide sensor 24 may be connected to downstream monitor 22 and may provide the data used to correct or adjust pulse oximetry variability measurements as provided herein.
- a carbon dioxide sensor 24 may provide information to the monitor 22 relating to a carbon dioxide concentration in the expired gas stream.
- Carbon dioxide concentration measurements e.g., capnography
- end-tidal CO 2 the level of carbon dioxide released at the end of expiration
- capnography measurements may be performed by a separate processor-based device, or may be performed by the ventilator 18.
- the ventilator 18 may provide information to the monitor 22 relating to the timing of the expiration and inhalation, For example, the respiration timing information may be used to control the carbon dioxide sensor 24.
- the respiratory system 10 may include, either instead of or in addition to carbon dioxide sensor/s 24, any number of additional sensor types.
- aquametry sensor 26 may be a sensor that may be applied to a patient's tissue for determining a tissue water fraction.
- the aquametry sensor 26 may include any suitable arrangement of optical components for spectrophotometrically assessing the patient's tissue water fraction,
- the aquametry sensor 26 and the pulse oximetry sensor 20 may be integrated into a unitary sensor body.
- the downstream monitor 22 may receive signals, for example from ventilator 18 or from one or more sensors 24 or 26, to correct or adjust pulse oximetry signals received from pulse oximetry sensor 20.
- FIG. 2 is a block diagram of an embodiment of a monitor 22 that may be configured to implement the embodiments of the present disclosure.
- the pulse oximetiy signal from the pulse oximetry sensor 20 may generate a plethysmographic waveform, which may be further processed and corrected by the monitor 22,
- the monitor 22 may receive and further process a signal from carbon dioxide sensor 24 to determine a value representative of a concentration of carbon dioxide in the respiratory circuit 16 and/or a signal from aquametry sensor 26 to determine a value representative of a tissue water fraction of the patient.
- the monitor 22 may include a microprocessor 32 coupled to an internal bus 34.
- a time processing unit (TPU) 40 may provide timing control signals to light drive circuitry 42, which controls when an optical sensor (e.g., pulse oximetry sensor 20, carbon dioxide sensor 24, or tissue water fraction sensor 26) is activated, and, if multiple light sources are used, the multiplexed timing for the different light sources.
- TPU 40 may also control the gating-in of signals from sensor 20 through an amplifier 43 and a switching circuit 44. These signals are sampled at the proper time, depending at least in part upon which of multiple light sources is activated, if multiple light sources are used.
- the received signal from the pulse oximetry sensor 20 may be passed through an amplifier 46, a low pass filter 48, and an analog-to-digital converter 40.
- the digital data may then be stored in a queued serial module (QSM) 52, for later downloading to RAM 46 or ROM 56 as QSM 52 fills up.
- QSM queued serial module
- microprocessor 32 may calculate the oxygen saturation using various algorithms.
- the microprocessor 32 may calculate a plethysmography waveform variation using various algorithms, such as suitable statistical or time-series analysis algorithms.
- the plethysmograhpic waveform variation may be corrected based on input signals from other sensors (e.g., carbon dioxide sensor 24 or aquametry sensor 26), the ventilator 18, or caregiver inpiits to control inputs 54.
- the caregiver may input a patient's age, weight, gender, or information about the patient's clinical condition that may be relevant to the accurate estimation of the intravascular volume.
- These algorithms may employ certain coefficients, which may be empirically determined, and may correspond to the wavelengths of light used.
- the algorithms may employ additional correction coefficients.
- a particular end tidal carbon dioxide measurement as generated from a signal provided by carbon dioxide sensor 24, may be associated with a particular correction coefficient.
- the algorithms and coefficients may be stored in a ROM 56 or other suitable computer-readable storage medium and accessed and operated according to microprocessor 32 instructions.
- the correction coefficients may be provided as a lookup table.
- FIG. 3 is a process flow diagram illustrating a method 64 in accordance with some embodiments.
- the method may be performed as an automated procedure by a system, such as system 10.
- certain steps of the method may be performed by a processor, or a processor-based device such as a patient monitor 22 that includes instructions for implementing certain steps of the method 64.
- the method 64 begins with obtaining a plethysmographic waveform signal from a pulse oximetry sensor 20 at step 66. Additional data relating to one or more patient parameters is obtained at step 68.
- the data relating to one or more patient parameters may be received from the ventilator 18, or may be calculated from signals received from patient sensors, e.g., carbon dioxide sensor 24 or aquametry sensor 26.
- the data relating to one or more patient parameters may be manually input by a healthcare provider.
- the monitor 22 may perform, analysis of the plethysmography waveform signal and calculation of the plethysmography waveform variability at step 70 based on the plethysmography waveform signal obtained at step 66 and the additional patient parameter data obtained at step 68.
- the mathematical model for adjusting the waveform variability based on additional patient parameters obtained in step 68 may be linear or nonlinear, multivariate, partial least squares, principal component regression, auto- regressive moving average, mathematical curve fitting or simply an additive constant to the variability value,
- the waveform variability is first calculated to provide a percentage value, and then the percentage value is adjusted based on the patient parameters.
- the plethysmography waveform signal may be modified or filtered based on the patient parameters prior to the calculation of the waveform variability to provide an adjusted or corrected variability value. For example, if a patient parameter is associated with having a damping effect on the waveform, the damping effect may be quantified and a filter may be used to remove the damping effect.
- the variability of the AC component (i.e., the pulsatile component) of the plethysmography waveform signal, and not the DC component (i.e., the nonpulsatile component) may be used for assessing the intravascular blood volume. Accordingly, the DC component may be filtered out or otherwise removed from the waveform prior to the analysis in step 70.
- W max is a maximum peak value, taken as a vertical distance 82 between a peak 84 and trough 86 for a largest peak 88 (i.e., a single cardiac cycle) and W m i n is a minimum peak value, taken as vertical distance 90 between a peak 92 and trough 94 for a smallest peak 96 within a window 98 of consecutive peaks.
- W mea ⁇ represents the mean vertical distance between peak maxima and minima for the consecutive peaks in the window 98.
- the window 98 may be a total number of peaks, such as 5 consecutive peaks, or may include all consecutive peaks within a time window, such as 10 seconds.
- an operator may adjust the settings on a monitor to change the size of the window according to the desired monitoring parameters. For example, an operator may increase the size of the window 98 from 10 seconds to 30 seconds to capture more data prior to providing the waveform variability. TMs may provide more accurate and/or stable waveform variability values, but may also slow the updating.
- the monitor 22 may provide rolling updates as the window 98 moves forward in time.
- one or more patient parameters may be used to adjust or correct the calculated plethysmographic waveform variability at step 70.
- certain patient conditions may influence or have a correlative or inverse correlative relationship with the plethysmograpliic waveform.
- the plethysmographic waveform variability may be particularly sensitive to vasoconstriction.
- the monitor 22 may allow a clinician to input information into the monitor related to whether or not the patient is taking any vasoconstrictive drugs, such as vasopressin analogs. Because vasoconstriction may increase cardiac preload and cardiac output, the resultant plethysmographic waveform may be adjusted to account for the effects of vasoconstrictive drugs.
- vasoconstriction including stress and hypothermia.
- information from temperature sensors may provide information about whether or not vasoconstriction may be a factor in influencing the plethysmographic waveform variability.
- the plethysmographic waveform variability may be adjusted accordingly.
- PEEP positive end expiratory pressure
- PEEP may increase intrathoracic pressure, leading to a resulting decrease in venous return and decrease in cardiac output. Accordingly, information relating to PEEP may be used to adjust the plethysmographic waveform variability to a lower threshold value indicative of hypovolemia, as discussed below. For example, because PEEP and intravascular volume depletion may be contraindicated, a patient receiving PEEP may be closely monitored for hypovolemia and may have a lower plethysmograhpic waveform variability threshold. In addition, PEEP may lead to an increase in plethysmographic waveform variability, meaning that the plethysmographic waveform variability may be adjusted downwards to account for the effects of PEEP.
- a patient parameter may also be used to determine if plethysmographic waveform variability is likely to be accurate for the patient in question.
- the plethysmographic waveform variability value may be a generally accurate estimate of intravascular volume or fluid responsiveness. Accordingly, for these patients, the plethysmographic waveform variability value may not be adjusted when their tidal volumes are in the normal range. However, for patients outside of the range of normal tidal volumes, the plethysmographic waveform variability value may be less accurate and may be adjusted according to its relationship with tidal volumes outside of normal ranges.
- tissue water fraction information from an aquametry sensor 26 may be used to adjust the plethysmographic waveform variability. Because plethysmographic waveform variability may be used as a surrogate for blood volume, information about the hydration state of other compartments, such as the tissue, may provide additional information for assessing intravascular blood volume. Total body water depletion through dehydration may lead to poor intravascular volume. The body may protectively shunt blood towards the most vital organs (heart, kidney and brain) and away from peripheral organs such as the intestines, muscles and skin. Hence, the earliest sign of dehydration may be seen in the skin and muscle tissues, A reduced extracellular fluid volume, e.g., tissue water fraction, may be an early indicator of low intravascular volume.
- tissue water fraction may be an early indicator of low intravascular volume.
- a tissue water fraction may be determined according to methods discussed in U.S. Patent Application No. 11/716,443 to Hausmann et al, filed on March 9, 2007, the specification of which is incorporated by reference herein in its entirety for all purposes. If the tissue water fraction is associated with a low level of hydration, the plethysmographic waveform variability may be increased or adjusted upwards to reflect a higher likelihood of hypovolemia. In addition, the tissue water fraction may be used as a confirmation or confidence check for the plethysmograpliic waveform variability. Further, information from a carbon dioxide sensor 24 may be used to adjust the plethysmographic waveform variability. Abnormally low levels of carbon dioxide in end tidal breaths may correlate with a concurrent decrease in blood volume. Accordingly, the plethysmography waveform variability may be increased or adjusted upwards to reflect a higher likelihood of hypovolemia for patients with decreased end tidal carbon dioxide levels.
- the monitor 22 may calculate the adjusted plethysmographic variability value and provide a display or other indication to a clinician, such as a graphical, visual, or audio representation of the intravascular volume at step 72.
- a clinician such as a graphical, visual, or audio representation of the intravascular volume at step 72.
- an adjusted plethysmographic variability value associated with normal intravascular blood volume may include a numeric value or a green light indicated on a display or a short tone generated by a speaker associated with monitor 22.
- an adjusted plethysmographic variability value associated with hypovolemia may trigger an alarm, which may include one or more of an audio or visual alarm indication.
- the monitor 22 may provide a confidence metric or indicator to provide information to the clinician relating to how may parameters may have been taken into account. For example, if the plethysmographic variability value is consistent with trends from two or more additional patient parameters, the confidence may be higher than if only one patient parameter is used.
- the alarm may be triggered if the adjusted plethysmographic variability value is substantially greater than a predetermined value, substantially less than a predetermined value, or outside of a predetermined range.
- a plethysmographic variability value of 10-15% may be considered to be indicative of a non-responsive or normovolemic patient that would not benefit from a fluid infusion.
- a plethysmography variability value above 15% may be considered to be indicative of a hypovolemic patient that would likely benefit from a fluid infusion with respect to increasing cardiac output and improving the overall state of oxygenation. Accordingly, an alarm may be triggered when the plethysmographic waveform variability value is above 15% to alert a clinician that the patient may benefit from fluid therapy.
- a patient respiratory system 100 may operate under closed- loop control to provide to delivery of a fluid therapy (e.g., saline, blood, or other fluid) to a patient 14.
- FIG. 5 shows a system 100 under control of a primary controller 102 that may include a closed-loop controller that cooperates with a monitor 22 to control delivery of fluid therapy to the patient 14.
- the primary controller 102 may receive input from the monitor 22.
- the monitor 22 may calculate a plethysmographic waveform variability value.
- the plethysmographic waveform variability value may be used by the controller 102 to control the fluid delivery device 104. It should be understood that while FIG. 5 depicts the controller 102 and the monitor 22 as separate devices, the monitoring functions of monitor 22 and the controller functions of controller 102 may be incorporated into a single device in embodiments.
- the controller 102 may receive a request for increased fluid from the monitor 22 when a measured plethysmographic waveform variability value, adjusted with regard to available patient parameters, is above a predefined target, e.g., above 15%.
- the fluid delivery device 104 may include a peristaltic pump or other type of pump attached to an automatic intravenous line to achieve the desired delivery rate of the fluid to the patient.
- the speed of the pump may be controlled by the closed-loop controller 102.
- the controller 102 may slow or stop delivery of fluid from the fluid delivery device 104. If the monitor 22 fails to determine that a plethysmographic waveform variability value has decreased after a set time, the controller 102 may generate a signal notifying a caregiver of prolonged hypovolemia or may cease delivery of fluids.
Abstract
Embodiments of the present invention relate to a system and method for determining a physiologic parameter of a patient. Specifically, embodiments of the present invention include methods and systems for correcting a pulse oximetry plethysmographic waveform variability measurement based on parameters that may influence the waveform variability. The corrected measurement may be used to estimate intravascular blood volume and/or fluid responsiveness of a patient.
Description
MEDICAL DEVICE FOR ASSESSING INTRAVASCULAR BLOOD VOLUME AND TECHNIQUE FOR USING THE SAME
BACKGROUND
The present disclosure relates generally to a method and system for monitoring physiological parameters of a patient. Specifically, embodiments of the present invention relate to more accurate estimation of intravascular blood volume and fluid responsiveness by adjusting pulse oximetry waveform measurements to account for variations in respiratory parameters and/or other patient parameters.
This section is intended to introduce the reader to aspects of the art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
In the field of medicine, doctors often desire to monitor certain physiological characteristics of their patients. Accordingly, a wide variety of devices have been developed for monitoring many such characteristics of a patient. Such devices provide doctors and other healthcare personnel with the information they need to provide the best possible healthcare for their patients. As a result, such monitoring devices have become an indispensable part of modem medicine.
One physiological parameter that physicians may wish to monitor is blood fluid volume (i.e., intravascular volume). Variations from normal fluid volume in the blood may indicate a change in clinical condition or an injury. For example, hypovolemia is a
state of decreased intravascular volume that may be associated with dehydration. Correct clinical assessment of hypovolemia is complex. More specifically, intravascular volume is difficult to estimate, particularly in critically ill patients. Without an accurate assessment of a patient's intravascular volume, it is difficult to predict whether a patient will respond to fluid therapy (e.g., a blood or fluid infusion) with an improvement in clinical condition, such as an increase in stroke volume and cardiac output. Accordingly, accurate assessments of intravascular volume may assist a clinician in determining whether a patient will be responsive to fluid therapy.
To this end, indicators such as the systolic blood pressure variation, pulse pressure variation, or stroke volume variation may be used to estimate intravascular volume and determine whether a patient is likely to be fluid responsive. However, these measurements tend to be invasive. For example, to obtain an accurate pulse pressure waveform from which the intravascular volume can be determined, a physician may insert an invasive arterial line.
BRIEF DESCRIPTION OF THE DRAWINGS
Advantages of the disclosure may become apparent upon reading the following detailed description and upon reference to the drawings in which:
FIG. 1 is a block diagram of a ventilation system for determining intravascular blood volume in accordance with an embodiment;
FIG. 2 is a block diagram of a patient monitor that may be used in conjunction with the ventilation system of FIG. 1 in accordance with an embodiment;
FIG. 3 is a block diagram of a method illustrating an embodiment;
FIG. 4 is a plethysniographic waveform illustrating an embodiment; and
FIG. 5 is a block diagram of a closed-loop ventilation system for administering a fluid therapy in accordance with an embodiment.
DETAILED DESCRIPTION
One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions may be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vaiy from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.
For patients who are undergoing multiple and overlapping medical treatments, monitoring physiological parameters may be complex. For example, certain physiological characteristics of the patient may be influenced by the medical treatment being provided. Pn embodiments, a ventilator may control a patient's breathing rate along with the type and amount of gases inhaled. Because respiration affects the delivery of oxygen from the lungs into the blood, changes in ventilation parameters and/or patient lung conditions may
result in changes to hemodynamic parameters, such as pulse pressure and blood oxygenation.
The variability in a waveform representative of a patient's blood oxygen levels (i.e., a plethysmographic waveform) may be used to estimate a patient's intravascular volume. Blood oxygen levels may be monitored with a non-invasive, optical pulse oximetry sensor that transmits two or more wavelengths of light, most commonly red and near infrared wavelengths, through a patient's tissue and that photoelectrical^ detects the absorption and/or scattering of the transmitted light in such tissue. The use of pulse oximetry to estimate intravascular volume and fluid responsiveness in ventilated patients provides the ease of use of a noninvasive, rather than invasive, sensor. However, as noted, blood oxygen measurements may be affected by other clinical conditions, such as respiratory parameters. For example, the plethysmographic waveform signal may be sensitive to respiratory parameters, such as respiration rate, tidal volume, end tidal carbon dioxide concentration, or positive end-expiratory pressure, which may be controlled by particular settings on a ventilator. Tn addition, the plethysmographic waveform signal may be sensitive to tissue or blood constituent concentration, for example, a tissue water fraction or a partial pressure of carbon dioxide in the tissue. Further, the plethysmographic waveform signal may have certain patient-to-patient variability based on age, weight, gender, and clinical condition.
The plethysmographic waveform signal, or, in embodiments, a calculated value based on variation in the waveform signal, may be corrected or adjusted to provide a more accurate estimate of intravascular volume. A clinician may use the estimate of intravascular volume to make determinations about a patient's clinical condition, such as
the likelihood that the patient will respond to fluid therapy. The adjustment may correct for certain physiological conditions that may influence the plethysmographic waveform and that may either mask or exaggerate the plethysmographic waveform variability. For example, in the case of a ventilated patient with a controlled respiration rate, the patient's blood oxygen saturation, may be higher relative to a patient who is not receiving breathing assistance. Depending on the patient's clinical condition, a ventilated patient with generally higher respiration rate may have greater peak-to-peak variability in a plethysmographic waveform, which in turn would result in a higher calculated variability value. Typically, higher variability values (e.g., greater than 15% variability) may be associated with increased fluid responsiveness. Accordingly, an artificially high variability value may mask a patient's true fluid responsiveness.
By correcting the variability of the plethysmographic signal to account for the influence of patient parameters, such as a higher respiration rate as a result of ventilation, the resulting plethysmographic waveform variability value may be more accurate. Accordingly, a clinician may be able to make more informed decisions about whether the patient may benefit from fluid therapy. In addition, the clinician may be able to assess changes in blood volume more rapidly and may be able to intervene to provide therapy to the patient at an earlier time point. In embodiments, a closed-loop system is provided in which the corrected plethysmographic waveform variability is used to estimate the intravascular volume and determine the fluid responsiveness of a patient. A closed-loop controller may control delivery of fluid therapy if the estimate of intravascular volume is associated with hypovolemia, which, may indicate that the patient will be responsive to fluid therapy.
Embodiments provided herein are directed to medical devices for assessing intravascular volume based on respiratory or other patient parameters. Suitable devices may be incorporated into a respiratory system 10, shown in FIG. 1, or any other patient monitoring system. In one embodiment, the respiratory system 10 may include a tracheal tube 12, such as an endotracheal tube, that is inserted into a patient 14 to deliver gases to and from the patient's lungs. The respiratory system 10 may also include a respiratory circuit 16 connecting the tracheal tube 12 to a ventilator 18. In embodiments, the ventilator 18 may be a positive pressure ventilator, such as those available from Nellcor Puritan Bennett LLC.
The system 10 may also include a pulse oximetry sensor 20 for generating a plethysmography waveform signal representative of a patient's blood oxygen levels. The pulse oximetry sensor 20 may be in communication with a monitor 22 configured to receive the plethysmography waveform signal and estimate the patient's intravascular volume and/or fluid responsiveness. In one embodiment, the monitoring functions of the monitor 22 may be incorporated into a single device that also performs the functions of ventilator 18.
In embodiments, the plethysmographic waveform variability may be corrected by adjusting for respiratory parameters controlled by the ventilator 18. For example, the ventilator 18 may include a controller for controlling respiration rate, tidal volume, flow rate, pressure, peak airway pressure, ratio of expiration to inspiration time, fraction of inspired oxygen (i.e., the percentage of oxygen in the gas mixture), inspired pressure increases or decreases over each breath (e.g., positive end-expiratory pressure), and any other respiratory parameter. Any suitable respiratory parameter controlled by the
ventilator 18 may be used to adjust an estimate of intravascular volume, as discussed in more detail below.
The respiratory system 10 may also include any number or combination of additional sensors for providing information related to patient parameters that may be used to correct or adjust the estimate of the patient's intravascular volume and/or fluid responsiveness. For example, suitable sensors may include sensors for determining tissue hydration, tissue constituents, blood constituents, blood pressure, heart rate, patient temperature, or tissue impedance. Such sensors may also include sensors for determining the presence or concentration of biomarkers, including sensors for circulating biomarkers related to cardiac stress and function (e.g., troponin or cholesterol) and/or biomarkers associated with lung function (e.g., surfactant protein D).
Suitable sensors for providing information about additional patient parameters may be optical, electrical, chemical, or biological sensors. A carbon dioxide sensor or tissue water fraction sensor may direct two or more wavelengths of light, most commonly near infrared wavelengths between about 1,000 nm to about 2,500 nm, into a sample, e.g., a gas sample or a tissue sample, Other sensors may include electrical sensors, such as electrical impedance sensors that may sense a voltage drop between two electrodes that are applied to a patient's tissue. Chemical sensors may include colorimetric chemical sensors, such as colorimetric sensors for detection of carbon dioxide. For example, a chemical sensor for carbon dioxide may include an indicator solution containing hydroxyl ions or amine residues that react chemically with carbon dioxide to form a carbonate and/or a bicarbonate or carbamate moiety, such as those discussed in co-pending U.S. Application No. 11/526,393 by Ostrowski et al., filed on September 25, 2006, the
specification of which is incorporated by reference in its entirety herein for all purposes. This reaction may ultimately result in a color change that may be optically detected. Biological sensors may include enzymatic sensors for detecting a color or fluorescence change produced by enzymatic reactions or by antibody/ligand binding. For example, surfactant protein D may be detected by an enzyme-linked immunosorbent assay available from Cell Sciences (Canton, MA).
By way of example, FIG. 1 shows a carbon dioxide sensor 24 that may be associated with the respiratory circuit 16 and an aquametry sensor 26 that may be applied to an appropriate tissue location on the patient 14. However, it should be understood that carbon dioxide sensor 24 and aquametiy sensor 26 are merely illustrative of sensor types that may be used in conjunction with the respiratory system 10. The carbon dioxide sensor 24 may be disposed along the respiratory circuit 16 (e.g., within a tube or connector of the respiratory circuit 16) or associated with the respiratory circuit 16. Ln addition, the carbon dioxide sensor 24 may be applied to a patient's tissue for determining partial pressure of carbon dioxide by optically interrogating the tissue. Carbon dioxide sensor 24 may be connected to downstream monitor 22 and may provide the data used to correct or adjust pulse oximetry variability measurements as provided herein. For example, a carbon dioxide sensor 24 may provide information to the monitor 22 relating to a carbon dioxide concentration in the expired gas stream. Carbon dioxide concentration measurements, e.g., capnography, may be used to estimate carbon dioxide partial pressure in arterial blood, hi one embodiment, end-tidal CO2 (the level of carbon dioxide released at the end of expiration) may be determined through capnography, which may be implemented by monitor 22. In other embodiments, the capnography
measurements may be performed by a separate processor-based device, or may be performed by the ventilator 18. To coordinate the measurement of end-tidal CO2 with the timing of the expiration, the ventilator 18 may provide information to the monitor 22 relating to the timing of the expiration and inhalation, For example, the respiration timing information may be used to control the carbon dioxide sensor 24.
The respiratory system 10 may include, either instead of or in addition to carbon dioxide sensor/s 24, any number of additional sensor types. For example, aquametry sensor 26 may be a sensor that may be applied to a patient's tissue for determining a tissue water fraction. The aquametry sensor 26 may include any suitable arrangement of optical components for spectrophotometrically assessing the patient's tissue water fraction, In one embodiment, the aquametry sensor 26 and the pulse oximetry sensor 20 may be integrated into a unitary sensor body.
The downstream monitor 22 may receive signals, for example from ventilator 18 or from one or more sensors 24 or 26, to correct or adjust pulse oximetry signals received from pulse oximetry sensor 20. FIG. 2 is a block diagram of an embodiment of a monitor 22 that may be configured to implement the embodiments of the present disclosure. The pulse oximetiy signal from the pulse oximetry sensor 20 may generate a plethysmographic waveform, which may be further processed and corrected by the monitor 22, The monitor 22 may receive and further process a signal from carbon dioxide sensor 24 to determine a value representative of a concentration of carbon dioxide in the respiratory circuit 16 and/or a signal from aquametry sensor 26 to determine a value representative of a tissue water fraction of the patient.
The monitor 22 may include a microprocessor 32 coupled to an internal bus 34. Also connected to the bus may be a RAM memory 36 and a display 38. A time processing unit (TPU) 40 may provide timing control signals to light drive circuitry 42, which controls when an optical sensor (e.g., pulse oximetry sensor 20, carbon dioxide sensor 24, or tissue water fraction sensor 26) is activated, and, if multiple light sources are used, the multiplexed timing for the different light sources. TPU 40 may also control the gating-in of signals from sensor 20 through an amplifier 43 and a switching circuit 44. These signals are sampled at the proper time, depending at least in part upon which of multiple light sources is activated, if multiple light sources are used. The received signal from the pulse oximetry sensor 20 may be passed through an amplifier 46, a low pass filter 48, and an analog-to-digital converter 40. The digital data may then be stored in a queued serial module (QSM) 52, for later downloading to RAM 46 or ROM 56 as QSM 52 fills up.
In an embodiment, based at least in part upon the received signals corresponding to the light received by optical components of the pulse oximetry sensor 20, microprocessor 32 may calculate the oxygen saturation using various algorithms. In addition, the microprocessor 32 may calculate a plethysmography waveform variation using various algorithms, such as suitable statistical or time-series analysis algorithms. The plethysmograhpic waveform variation may be corrected based on input signals from other sensors (e.g., carbon dioxide sensor 24 or aquametry sensor 26), the ventilator 18, or caregiver inpiits to control inputs 54. For example, the caregiver may input a patient's age, weight, gender, or information about the patient's clinical condition that may be relevant to the accurate estimation of the intravascular volume. These algorithms may
employ certain coefficients, which may be empirically determined, and may correspond to the wavelengths of light used. In addition, the algorithms may employ additional correction coefficients. By way of example, a particular end tidal carbon dioxide measurement, as generated from a signal provided by carbon dioxide sensor 24, may be associated with a particular correction coefficient. The algorithms and coefficients may be stored in a ROM 56 or other suitable computer-readable storage medium and accessed and operated according to microprocessor 32 instructions. In one embodiment, the correction coefficients may be provided as a lookup table.
A patient's intravascular volume may be determined based on the corrected variability of a pulse oximetry plethysmographic waveform that is adjusted based on patient parameters. FIG. 3 is a process flow diagram illustrating a method 64 in accordance with some embodiments. The method may be performed as an automated procedure by a system, such as system 10. In addition, certain steps of the method may be performed by a processor, or a processor-based device such as a patient monitor 22 that includes instructions for implementing certain steps of the method 64.
According to an embodiment, the method 64 begins with obtaining a plethysmographic waveform signal from a pulse oximetry sensor 20 at step 66. Additional data relating to one or more patient parameters is obtained at step 68. The data relating to one or more patient parameters may be received from the ventilator 18, or may be calculated from signals received from patient sensors, e.g., carbon dioxide sensor 24 or aquametry sensor 26. In addition, the data relating to one or more patient parameters may be manually input by a healthcare provider.
The monitor 22 may perform, analysis of the plethysmography waveform signal and calculation of the plethysmography waveform variability at step 70 based on the plethysmography waveform signal obtained at step 66 and the additional patient parameter data obtained at step 68. The mathematical model for adjusting the waveform variability based on additional patient parameters obtained in step 68 may be linear or nonlinear, multivariate, partial least squares, principal component regression, auto- regressive moving average, mathematical curve fitting or simply an additive constant to the variability value, In one embodiment, the waveform variability is first calculated to provide a percentage value, and then the percentage value is adjusted based on the patient parameters.
Li embodiments, the plethysmography waveform signal may be modified or filtered based on the patient parameters prior to the calculation of the waveform variability to provide an adjusted or corrected variability value. For example, if a patient parameter is associated with having a damping effect on the waveform, the damping effect may be quantified and a filter may be used to remove the damping effect. In addition, the variability of the AC component (i.e., the pulsatile component) of the plethysmography waveform signal, and not the DC component (i.e., the nonpulsatile component), may be used for assessing the intravascular blood volume. Accordingly, the DC component may be filtered out or otherwise removed from the waveform prior to the analysis in step 70.
FIG. 4 illustrates a plethysmography waveform 80 from which the plethysmographic waveform variability, Wv, may be determined based on the following equation:
Wv= (Wmax-Wmin)/Wrae;ιll
where Wmax is a maximum peak value, taken as a vertical distance 82 between a peak 84 and trough 86 for a largest peak 88 (i.e., a single cardiac cycle) and Wmin is a minimum peak value, taken as vertical distance 90 between a peak 92 and trough 94 for a smallest peak 96 within a window 98 of consecutive peaks. Wmeaι, represents the mean vertical distance between peak maxima and minima for the consecutive peaks in the window 98. The window 98 may be a total number of peaks, such as 5 consecutive peaks, or may include all consecutive peaks within a time window, such as 10 seconds. In embodiments, an operator may adjust the settings on a monitor to change the size of the window according to the desired monitoring parameters. For example, an operator may increase the size of the window 98 from 10 seconds to 30 seconds to capture more data prior to providing the waveform variability. TMs may provide more accurate and/or stable waveform variability values, but may also slow the updating. The monitor 22 may provide rolling updates as the window 98 moves forward in time.
Turning back to FIG. 3, one or more patient parameters may be used to adjust or correct the calculated plethysmographic waveform variability at step 70. In general, certain patient conditions may influence or have a correlative or inverse correlative relationship with the plethysmograpliic waveform. For example, the plethysmographic waveform variability may be particularly sensitive to vasoconstriction. In embodiments, the monitor 22 may allow a clinician to input information into the monitor related to whether or not the patient is taking any vasoconstrictive drugs, such as vasopressin analogs. Because vasoconstriction may increase cardiac preload and cardiac output, the resultant plethysmographic waveform may be adjusted to account for the effects of
vasoconstrictive drugs. Similarly, certain clinical conditions may cause vasoconstriction, including stress and hypothermia. Accordingly, information from temperature sensors may provide information about whether or not vasoconstriction may be a factor in influencing the plethysmographic waveform variability. When patient parameters indicative of vasoconstriction are available, the plethysmographic waveform variability may be adjusted accordingly.
Similarly, information relating to whether or not a patient is receiving positive end expiratory pressure (PEEP) ventilation may be used to adjust the plethysmographic waveform variability. PEEP can cause significant hemodynamic consequences through decreasing venous return to the right heart and decreasing right ventricular function.
PEEP may increase intrathoracic pressure, leading to a resulting decrease in venous return and decrease in cardiac output. Accordingly, information relating to PEEP may be used to adjust the plethysmographic waveform variability to a lower threshold value indicative of hypovolemia, as discussed below. For example, because PEEP and intravascular volume depletion may be contraindicated, a patient receiving PEEP may be closely monitored for hypovolemia and may have a lower plethysmograhpic waveform variability threshold. In addition, PEEP may lead to an increase in plethysmographic waveform variability, meaning that the plethysmographic waveform variability may be adjusted downwards to account for the effects of PEEP.
A patient parameter may also be used to determine if plethysmographic waveform variability is likely to be accurate for the patient in question. For example for patients with normal tidal volumes, e.g., between 8 and 15 kg/ml, the plethysmographic waveform variability value may be a generally accurate estimate of intravascular volume or fluid
responsiveness. Accordingly, for these patients, the plethysmographic waveform variability value may not be adjusted when their tidal volumes are in the normal range. However, for patients outside of the range of normal tidal volumes, the plethysmographic waveform variability value may be less accurate and may be adjusted according to its relationship with tidal volumes outside of normal ranges.
In embodiments, tissue water fraction information from an aquametry sensor 26 may be used to adjust the plethysmographic waveform variability. Because plethysmographic waveform variability may be used as a surrogate for blood volume, information about the hydration state of other compartments, such as the tissue, may provide additional information for assessing intravascular blood volume. Total body water depletion through dehydration may lead to poor intravascular volume. The body may protectively shunt blood towards the most vital organs (heart, kidney and brain) and away from peripheral organs such as the intestines, muscles and skin. Hence, the earliest sign of dehydration may be seen in the skin and muscle tissues, A reduced extracellular fluid volume, e.g., tissue water fraction, may be an early indicator of low intravascular volume. A tissue water fraction may be determined according to methods discussed in U.S. Patent Application No. 11/716,443 to Hausmann et al, filed on March 9, 2007, the specification of which is incorporated by reference herein in its entirety for all purposes. If the tissue water fraction is associated with a low level of hydration, the plethysmographic waveform variability may be increased or adjusted upwards to reflect a higher likelihood of hypovolemia. In addition, the tissue water fraction may be used as a confirmation or confidence check for the plethysmograpliic waveform variability.
Further, information from a carbon dioxide sensor 24 may be used to adjust the plethysmographic waveform variability. Abnormally low levels of carbon dioxide in end tidal breaths may correlate with a concurrent decrease in blood volume. Accordingly, the plethysmography waveform variability may be increased or adjusted upwards to reflect a higher likelihood of hypovolemia for patients with decreased end tidal carbon dioxide levels.
The monitor 22 may calculate the adjusted plethysmographic variability value and provide a display or other indication to a clinician, such as a graphical, visual, or audio representation of the intravascular volume at step 72. For example, an adjusted plethysmographic variability value associated with normal intravascular blood volume may include a numeric value or a green light indicated on a display or a short tone generated by a speaker associated with monitor 22. Similarly, an adjusted plethysmographic variability value associated with hypovolemia may trigger an alarm, which may include one or more of an audio or visual alarm indication. Further, the monitor 22 may provide a confidence metric or indicator to provide information to the clinician relating to how may parameters may have been taken into account. For example, if the plethysmographic variability value is consistent with trends from two or more additional patient parameters, the confidence may be higher than if only one patient parameter is used.
In one embodiment, the alarm may be triggered if the adjusted plethysmographic variability value is substantially greater than a predetermined value, substantially less than a predetermined value, or outside of a predetermined range. In one embodiment, a plethysmographic variability value of 10-15% may be considered to be indicative of a
non-responsive or normovolemic patient that would not benefit from a fluid infusion. In addition, a plethysmography variability value above 15% may be considered to be indicative of a hypovolemic patient that would likely benefit from a fluid infusion with respect to increasing cardiac output and improving the overall state of oxygenation. Accordingly, an alarm may be triggered when the plethysmographic waveform variability value is above 15% to alert a clinician that the patient may benefit from fluid therapy.
In other embodiments, a patient respiratory system 100 may operate under closed- loop control to provide to delivery of a fluid therapy (e.g., saline, blood, or other fluid) to a patient 14. FIG. 5 shows a system 100 under control of a primary controller 102 that may include a closed-loop controller that cooperates with a monitor 22 to control delivery of fluid therapy to the patient 14. The primary controller 102 may receive input from the monitor 22. Based on the plethysmographic waveform signal from the pulse oximetry sensor 20 as well as additional patient parameter information, such as the settings of ventilator 18 or the inputs from additional patient sensors, the monitor 22 may calculate a plethysmographic waveform variability value. The plethysmographic waveform variability value may be used by the controller 102 to control the fluid delivery device 104. It should be understood that while FIG. 5 depicts the controller 102 and the monitor 22 as separate devices, the monitoring functions of monitor 22 and the controller functions of controller 102 may be incorporated into a single device in embodiments.
For example, the controller 102 may receive a request for increased fluid from the monitor 22 when a measured plethysmographic waveform variability value, adjusted with regard to available patient parameters, is above a predefined target, e.g., above 15%. The fluid delivery device 104 may include a peristaltic pump or other type of pump attached to
an automatic intravenous line to achieve the desired delivery rate of the fluid to the patient. To control the rate at which the pump infuses the fluid, the speed of the pump may be controlled by the closed-loop controller 102. When the plethysmography waveform variability value falls below 15%, the controller 102 may slow or stop delivery of fluid from the fluid delivery device 104. If the monitor 22 fails to determine that a plethysmographic waveform variability value has decreased after a set time, the controller 102 may generate a signal notifying a caregiver of prolonged hypovolemia or may cease delivery of fluids.
While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the invention as defined by the following appended claims.
Claims
1. A method, comprising: using a processor: receiving a plethysmographic waveform signal from a sensor, wherein the plethysmographic waveform signal is generally representative of a blood oxygen saturation of a patient; receiving information related to a patient parameter that may influence the plethysmographic waveform signal; and determining plethysmographic waveform variability based at least in part on the plethysmography waveform signal and/or the information related to the patient parameter.
2. The method of claim 1, comprising providing an indication of intravascular blood volume based on the plethysmographic waveform variability,
3. The method of claim 1, comprising triggering an alarm when the plethysmographic waveform variability is greater than a predetermined level or outside of a predetermined range.
4. The method of claim 3, wherein the predetermined level is about 15%.
5. The method of claim 1, wherein the information related to the patient parameter comprises a tissue carbon dioxide level, a tissue water fraction, and/or a combination thereof.
6. The method of claim 1, wherein the information related to the patient parameter comprises a ventilator setting of positive end pressure ventilation, a tidal volume, a respiration rate, an end-tidal carbon dioxide level, and/or any combination thereof,
7. The method of claim 1 , wherein the information related to the patient parameter comprises a clinical condition of the patient and/or information related to a pharmacological treatment.
8. The method of claim 7, wherein the clinical condition comprises a likelihood of vasoconstriction,
9. A monitor, comprising: an input circuit capable of receiving a plethysmography waveform signal and information relating to a patient parameter that influences the plethysmographic waveform signal; a memoiy storing an algorithm configured to calculate a plethysmograhpic waveform variability based at least in part on the plethysmographic waveform signal and/or the information related to the patient parameter; and an output circuit configured to provide an indication of the plethysmograhpic waveform variability.
10. The monitor of claim 9, wherein the information relating to a patient parameter comprises information received from a carbon dioxide sensor and/or a tissue water fraction sensor.
11. The monitor of claim 9, wherein the information relating to a patient parameter comprises respiratory parameter information.
12. The monitor of claim 9, wherein the algorithm comprises the following equation:
Wv= (Wmax-Wmin)/Wmcan,
wherein Wv is the plethysmograhpic waveform variability, Wmax is a maximum peak value for a largest peak, Wmin is a minimum peak value for a smallest peak, and Wniean represents the mean vertical distance between peak maxima and minima for the consecutive peaks in the window within a window of consecutive peaks.
13. The monitor of claim 9, wherein the information related to the patient parameter comprises a tidal volume, and wherein the algorithm is configured to adjust the plethysniographic waveform variability when the tidal volume is outside of a range of between about 8 to about 15 kg/ml.
14. The monitor of claim 9, wherein the information relating to the patient parameter comprises information that the patient is undergoing positive end expiratory pressure ventilation, and wherein the algorithm is configured to increase the plethysmographic waveform variability based on the information.
15. The monitor of claim 9, wherein the information relating to the patient parameter comprises information that the patient is receiving vasoconstrictive drugs, and wherein the algorithm is configured to adjust the plethysmographic waveform variability based on the information.
16. A system for automatically controlling delivery of a fluid, comprising: a delivery mechanism capable of delivering a fluid to a patient; and a controller, wherein the controller is capable of: receiving a plethysmograhpic waveform signal and information relating to a patient parameter that influences the plethysmographic waveform signal; detemiining a plethysmograhpic waveform variability based at least in part on the plethysmographic waveform signal and the information related to the patient parameter; and generally automatically adjusting delivery of the fluid based on a comparison of the plethysmograhpic waveform variability with a predetermined value.
17. The system of claim 16, comprising a ventilator capable of delivering a gas mixture to the patient, wherein the information related to the patient parameter comprises a setting or parameter of the ventilator.
18. The system of claim 16, wherein the delivery mechanism is capable of delivering the fluid comprises an intravenous fluid pump.
19. The system of claim 16, comprising a sensor capable of providing the information related to the patient parameter physiologic parameter.
20. The system of claim 19, wherein the sensor comprises a carbon dioxide sensor and/or a tissue water fraction sensor.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
EP10710136.2A EP2410904B1 (en) | 2009-03-25 | 2010-03-16 | Medical device for assessing intravascular blood volume and technique for using the same |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US12/411,014 | 2009-03-25 | ||
US12/411,014 US8221319B2 (en) | 2009-03-25 | 2009-03-25 | Medical device for assessing intravascular blood volume and technique for using the same |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2010111073A1 true WO2010111073A1 (en) | 2010-09-30 |
Family
ID=42196922
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US2010/027508 WO2010111073A1 (en) | 2009-03-25 | 2010-03-16 | Medical device for assessing intravascular blood volume and technique for using the same |
Country Status (3)
Country | Link |
---|---|
US (1) | US8221319B2 (en) |
EP (1) | EP2410904B1 (en) |
WO (1) | WO2010111073A1 (en) |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2301613A1 (en) * | 2009-09-29 | 2011-03-30 | General Electric Company | Method, arrangement and apparatus for assessing fluid balance status of a subject |
WO2013027151A1 (en) * | 2011-08-25 | 2013-02-28 | Koninklijke Philips Electronics N.V. | Method and apparatus for controlling a ventilation therapy device |
WO2014043302A1 (en) * | 2012-09-12 | 2014-03-20 | Covidien Lp | Systems and methods for determining fluid responsiveness |
WO2014043299A1 (en) * | 2012-09-12 | 2014-03-20 | Covidien Lp | Systems and methods for determining fluid responsiveness |
US8776792B2 (en) | 2011-04-29 | 2014-07-15 | Covidien Lp | Methods and systems for volume-targeted minimum pressure-control ventilation |
US8977348B2 (en) | 2012-12-21 | 2015-03-10 | Covidien Lp | Systems and methods for determining cardiac output |
US9060745B2 (en) | 2012-08-22 | 2015-06-23 | Covidien Lp | System and method for detecting fluid responsiveness of a patient |
US9241646B2 (en) | 2012-09-11 | 2016-01-26 | Covidien Lp | System and method for determining stroke volume of a patient |
US9357937B2 (en) | 2012-09-06 | 2016-06-07 | Covidien Lp | System and method for determining stroke volume of an individual |
US11058303B2 (en) | 2012-09-14 | 2021-07-13 | Covidien Lp | System and method for determining stability of cardiac output |
US11324954B2 (en) | 2019-06-28 | 2022-05-10 | Covidien Lp | Achieving smooth breathing by modified bilateral phrenic nerve pacing |
Families Citing this family (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11395594B2 (en) | 2008-10-29 | 2022-07-26 | Flashback Technologies, Inc. | Noninvasive monitoring for fluid resuscitation |
US11395634B2 (en) | 2008-10-29 | 2022-07-26 | Flashback Technologies, Inc. | Estimating physiological states based on changes in CRI |
US11857293B2 (en) | 2008-10-29 | 2024-01-02 | Flashback Technologies, Inc. | Rapid detection of bleeding before, during, and after fluid resuscitation |
US11478190B2 (en) | 2008-10-29 | 2022-10-25 | Flashback Technologies, Inc. | Noninvasive hydration monitoring |
US8512260B2 (en) | 2008-10-29 | 2013-08-20 | The Regents Of The University Of Colorado, A Body Corporate | Statistical, noninvasive measurement of intracranial pressure |
US11382571B2 (en) | 2008-10-29 | 2022-07-12 | Flashback Technologies, Inc. | Noninvasive predictive and/or estimative blood pressure monitoring |
US11406269B2 (en) | 2008-10-29 | 2022-08-09 | Flashback Technologies, Inc. | Rapid detection of bleeding following injury |
US20100324827A1 (en) * | 2009-06-18 | 2010-12-23 | Nellcor Puritan Bennett Ireland | Fluid Responsiveness Measure |
US8460200B2 (en) * | 2009-09-16 | 2013-06-11 | Analogic Corporation | Physiologic parameter monitoring apparatus |
US9554739B2 (en) | 2009-09-29 | 2017-01-31 | Covidien Lp | Smart cable for coupling a medical sensor to an electronic patient monitor |
US9414753B2 (en) * | 2009-10-20 | 2016-08-16 | Worcester Polytechnic Institute | Apparatus and method for respiratory rate detection and early detection of blood loss volume |
CA3123171A1 (en) | 2011-01-12 | 2012-07-19 | The Regents Of The University Of California | System and method for closed-loop patient-adaptive hemodynamic management |
WO2013016212A1 (en) * | 2011-07-22 | 2013-01-31 | Flashback Technologies, Inc. | Hemodynamic reserve monitor and hemodialysis control |
US8880155B2 (en) * | 2012-02-24 | 2014-11-04 | Covidien Lp | Hypovolemia diagnosis technique |
US8731649B2 (en) | 2012-08-30 | 2014-05-20 | Covidien Lp | Systems and methods for analyzing changes in cardiac output |
WO2014176576A1 (en) * | 2013-04-25 | 2014-10-30 | Covidien Lp | Systems and methods for determining fluid responsiveness |
WO2014176190A1 (en) | 2013-04-25 | 2014-10-30 | Covidien Lp | System and method for generating an adjusted fluid responsiveness metric |
WO2015017851A1 (en) * | 2013-08-02 | 2015-02-05 | Matthews Dawn C | Method for analyzing and correcting measurement variability in pet images |
US10328202B2 (en) | 2015-02-04 | 2019-06-25 | Covidien Lp | Methods and systems for determining fluid administration |
US10499835B2 (en) | 2015-03-24 | 2019-12-10 | Covidien Lp | Methods and systems for determining fluid responsiveness in the presence of noise |
US20190000386A1 (en) * | 2015-10-14 | 2019-01-03 | Kyocera Corporation | Measurement device |
KR20190094214A (en) | 2016-12-15 | 2019-08-12 | 백스터 인터내셔널 인코포레이티드 | System and method for monitoring and determining patient parameters from sensed vein waveforms |
US11039754B2 (en) | 2018-05-14 | 2021-06-22 | Baxter International Inc. | System and method for monitoring and determining patient parameters from sensed venous waveform |
US11918386B2 (en) | 2018-12-26 | 2024-03-05 | Flashback Technologies, Inc. | Device-based maneuver and activity state-based physiologic status monitoring |
US20230225621A1 (en) * | 2022-01-20 | 2023-07-20 | Guy P. Curtis | System and method for evaluating cardiac pumping function |
Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6099481A (en) * | 1997-11-03 | 2000-08-08 | Ntc Technology, Inc. | Respiratory profile parameter determination method and apparatus |
WO2002075289A2 (en) * | 2001-03-16 | 2002-09-26 | Nellcor Puritan Bennett Incorporated | Method and apparatus for improving the accuracy of noninvasive hematocrit measurements |
US20040260186A1 (en) * | 2002-02-22 | 2004-12-23 | Dekker Andreas Lubbertus Aloysius Johannes | Monitoring physiological parameters based on variations in a photoplethysmographic signal |
US20060058691A1 (en) * | 2004-09-07 | 2006-03-16 | Kiani Massi E | Noninvasive hypovolemia monitor |
WO2006086085A2 (en) * | 2004-12-28 | 2006-08-17 | Hypermed, Inc. | Hyperspectral/multispectral imaging in determination, assessment and monitoring of systemic physiology and shock |
WO2008073855A2 (en) * | 2006-12-09 | 2008-06-19 | Masimo Corporation | Plethysmograph variability processor |
US20080200775A1 (en) * | 2007-02-20 | 2008-08-21 | Lynn Lawrence A | Maneuver-based plethysmographic pulse variation detection system and method |
US20090076462A1 (en) * | 2007-09-13 | 2009-03-19 | Kiani Massi E | Fluid titration system |
Family Cites Families (672)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3638640A (en) | 1967-11-01 | 1972-02-01 | Robert F Shaw | Oximeter and method for in vivo determination of oxygen saturation in blood using three or more different wavelengths |
US3721813A (en) | 1971-02-01 | 1973-03-20 | Perkin Elmer Corp | Analytical instrument system |
GB8416219D0 (en) | 1984-06-26 | 1984-08-01 | Antec Systems | Patient monitoring apparatus |
JPS58143243A (en) | 1982-02-19 | 1983-08-25 | Minolta Camera Co Ltd | Measuring apparatus for coloring matter in blood without taking out blood |
US4770179A (en) | 1982-09-02 | 1988-09-13 | Nellcor Incorporated | Calibrated optical oximeter probe |
US4700708A (en) | 1982-09-02 | 1987-10-20 | Nellcor Incorporated | Calibrated optical oximeter probe |
US4621643A (en) | 1982-09-02 | 1986-11-11 | Nellcor Incorporated | Calibrated optical oximeter probe |
US4653498A (en) | 1982-09-13 | 1987-03-31 | Nellcor Incorporated | Pulse oximeter monitor |
US4830014A (en) | 1983-05-11 | 1989-05-16 | Nellcor Incorporated | Sensor having cutaneous conformance |
US5109849A (en) | 1983-08-30 | 1992-05-05 | Nellcor, Inc. | Perinatal pulse oximetry sensor |
US4938218A (en) | 1983-08-30 | 1990-07-03 | Nellcor Incorporated | Perinatal pulse oximetry sensor |
US5217013A (en) | 1983-10-14 | 1993-06-08 | Somanetics Corporation | Patient sensor for optical cerebral oximeter and the like |
US5140989A (en) | 1983-10-14 | 1992-08-25 | Somanetics Corporation | Examination instrument for optical-response diagnostic apparatus |
US4603700A (en) | 1983-12-09 | 1986-08-05 | The Boc Group, Inc. | Probe monitoring system for oximeter |
US4714341A (en) | 1984-02-23 | 1987-12-22 | Minolta Camera Kabushiki Kaisha | Multi-wavelength oximeter having a means for disregarding a poor signal |
IT1206462B (en) | 1984-08-07 | 1989-04-27 | Anic Spa | MULTI-WAVE LENGTH PULSED LIGHT PHOTOMETER FOR NON-INVASIVE MONITORING. |
USRE35122E (en) | 1985-04-01 | 1995-12-19 | Nellcor Incorporated | Method and apparatus for detecting optical pulses |
US4802486A (en) | 1985-04-01 | 1989-02-07 | Nellcor Incorporated | Method and apparatus for detecting optical pulses |
US4928692A (en) | 1985-04-01 | 1990-05-29 | Goodman David E | Method and apparatus for detecting optical pulses |
US4934372A (en) | 1985-04-01 | 1990-06-19 | Nellcor Incorporated | Method and apparatus for detecting optical pulses |
US4911167A (en) | 1985-06-07 | 1990-03-27 | Nellcor Incorporated | Method and apparatus for detecting optical pulses |
US4685464A (en) | 1985-07-05 | 1987-08-11 | Nellcor Incorporated | Durable sensor for detecting optical pulses |
US4936679A (en) | 1985-11-12 | 1990-06-26 | Becton, Dickinson And Company | Optical fiber transducer driving and measuring circuit and method for using same |
US4890619A (en) | 1986-04-15 | 1990-01-02 | Hatschek Rudolf A | System for the measurement of the content of a gas in blood, in particular the oxygen saturation of blood |
JPS6323645A (en) | 1986-05-27 | 1988-01-30 | 住友電気工業株式会社 | Reflection heating type oxymeter |
US4759369A (en) | 1986-07-07 | 1988-07-26 | Novametrix Medical Systems, Inc. | Pulse oximeter |
US4913150A (en) | 1986-08-18 | 1990-04-03 | Physio-Control Corporation | Method and apparatus for the automatic calibration of signals employed in oximetry |
US4869253A (en) | 1986-08-18 | 1989-09-26 | Physio-Control Corporation | Method and apparatus for indicating perfusion and oxygen saturation trends in oximetry |
US5259381A (en) | 1986-08-18 | 1993-11-09 | Physio-Control Corporation | Apparatus for the automatic calibration of signals employed in oximetry |
US4819646A (en) | 1986-08-18 | 1989-04-11 | Physio-Control Corporation | Feedback-controlled method and apparatus for processing signals used in oximetry |
US4800495A (en) | 1986-08-18 | 1989-01-24 | Physio-Control Corporation | Method and apparatus for processing signals used in oximetry |
US4892101A (en) | 1986-08-18 | 1990-01-09 | Physio-Control Corporation | Method and apparatus for offsetting baseline portion of oximeter signal |
US4859056A (en) | 1986-08-18 | 1989-08-22 | Physio-Control Corporation | Multiple-pulse method and apparatus for use in oximetry |
JPS6365845A (en) | 1986-09-05 | 1988-03-24 | ミノルタ株式会社 | Oximeter apparatus |
US4824242A (en) | 1986-09-26 | 1989-04-25 | Sensormedics Corporation | Non-invasive oximeter and method |
US4714080A (en) | 1986-10-06 | 1987-12-22 | Nippon Colin Co., Ltd. | Method and apparatus for noninvasive monitoring of arterial blood oxygen saturation |
US4865038A (en) | 1986-10-09 | 1989-09-12 | Novametrix Medical Systems, Inc. | Sensor appliance for non-invasive monitoring |
JPS63111837A (en) | 1986-10-29 | 1988-05-17 | 日本光電工業株式会社 | Apparatus for measuring concentration of light absorbing substance in blood |
US5193543A (en) | 1986-12-12 | 1993-03-16 | Critikon, Inc. | Method and apparatus for measuring arterial blood constituents |
US4776339A (en) | 1987-03-05 | 1988-10-11 | N.A.D., Inc. | Interlock for oxygen saturation monitor anesthesia apparatus |
US4880304A (en) | 1987-04-01 | 1989-11-14 | Nippon Colin Co., Ltd. | Optical sensor for pulse oximeter |
JPS63252239A (en) | 1987-04-09 | 1988-10-19 | Sumitomo Electric Ind Ltd | Reflection type oxymeter |
USRE33643E (en) | 1987-04-30 | 1991-07-23 | Nonin Medical, Inc. | Pulse oximeter with circuit leakage and ambient light compensation |
US4773422A (en) | 1987-04-30 | 1988-09-27 | Nonin Medical, Inc. | Single channel pulse oximeter |
JPS63275323A (en) | 1987-05-08 | 1988-11-14 | Hamamatsu Photonics Kk | Diagnostic apparatus |
JPS63277039A (en) | 1987-05-08 | 1988-11-15 | Hamamatsu Photonics Kk | Diagnostic apparatus |
GB8719333D0 (en) | 1987-08-14 | 1987-09-23 | Swansea University College Of | Motion artefact rejection system |
US4805623A (en) | 1987-09-04 | 1989-02-21 | Vander Corporation | Spectrophotometric method for quantitatively determining the concentration of a dilute component in a light- or other radiation-scattering environment |
US4796636A (en) | 1987-09-10 | 1989-01-10 | Nippon Colin Co., Ltd. | Noninvasive reflectance oximeter |
US4819752A (en) | 1987-10-02 | 1989-04-11 | Datascope Corp. | Blood constituent measuring device and method |
US4848901A (en) | 1987-10-08 | 1989-07-18 | Critikon, Inc. | Pulse oximeter sensor control system |
US4825879A (en) | 1987-10-08 | 1989-05-02 | Critkon, Inc. | Pulse oximeter sensor |
US4807630A (en) | 1987-10-09 | 1989-02-28 | Advanced Medical Systems, Inc. | Apparatus and method for use in pulse oximeters |
US4807631A (en) | 1987-10-09 | 1989-02-28 | Critikon, Inc. | Pulse oximetry system |
US4859057A (en) | 1987-10-13 | 1989-08-22 | Lawrence Medical Systems, Inc. | Oximeter apparatus |
US4863265A (en) | 1987-10-16 | 1989-09-05 | Mine Safety Appliances Company | Apparatus and method for measuring blood constituents |
US4854699A (en) | 1987-11-02 | 1989-08-08 | Nippon Colin Co., Ltd. | Backscatter oximeter |
EP0315040B1 (en) | 1987-11-02 | 1993-01-27 | Sumitomo Electric Industries Limited | Bio-photosensor |
US4781195A (en) | 1987-12-02 | 1988-11-01 | The Boc Group, Inc. | Blood monitoring apparatus and methods with amplifier input dark current correction |
US4800885A (en) | 1987-12-02 | 1989-01-31 | The Boc Group, Inc. | Blood constituent monitoring apparatus and methods with frequency division multiplexing |
US4846183A (en) | 1987-12-02 | 1989-07-11 | The Boc Group, Inc. | Blood parameter monitoring apparatus and methods |
US4927264A (en) | 1987-12-02 | 1990-05-22 | Omron Tateisi Electronics Co. | Non-invasive measuring method and apparatus of blood constituents |
US4960126A (en) | 1988-01-15 | 1990-10-02 | Criticare Systems, Inc. | ECG synchronized pulse oximeter |
US4883353A (en) | 1988-02-11 | 1989-11-28 | Puritan-Bennett Corporation | Pulse oximeter |
US4883055A (en) | 1988-03-11 | 1989-11-28 | Puritan-Bennett Corporation | Artificially induced blood pulse for use with a pulse oximeter |
DE3809084C2 (en) | 1988-03-18 | 1999-01-28 | Nicolay Gmbh | Sensor for the non-invasive measurement of the pulse frequency and / or the oxygen saturation of the blood and method for its production |
US4869254A (en) | 1988-03-30 | 1989-09-26 | Nellcor Incorporated | Method and apparatus for calculating arterial oxygen saturation |
US5078136A (en) | 1988-03-30 | 1992-01-07 | Nellcor Incorporated | Method and apparatus for calculating arterial oxygen saturation based plethysmographs including transients |
US4964408A (en) | 1988-04-29 | 1990-10-23 | Thor Technology Corporation | Oximeter sensor assembly with integral cable |
US5069213A (en) | 1988-04-29 | 1991-12-03 | Thor Technology Corporation | Oximeter sensor assembly with integral cable and encoder |
JPH06169902A (en) | 1988-05-05 | 1994-06-21 | Sentinel Monitoring Inc | Pulse type non-invasion type oxymeter and technology for measuring it |
DE3884191T2 (en) | 1988-05-09 | 1994-01-13 | Hewlett Packard Gmbh | Processing method of signals, especially for oximetry measurements in living human tissue. |
US5361758A (en) | 1988-06-09 | 1994-11-08 | Cme Telemetrix Inc. | Method and device for measuring concentration levels of blood constituents non-invasively |
US4948248A (en) | 1988-07-22 | 1990-08-14 | Invivo Research Inc. | Blood constituent measuring device and method |
US4825872A (en) | 1988-08-05 | 1989-05-02 | Critikon, Inc. | Finger sensor for pulse oximetry system |
JPH0288041A (en) | 1988-09-24 | 1990-03-28 | Misawahoomu Sogo Kenkyusho:Kk | Finger tip pulse wave sensor |
US5099842A (en) | 1988-10-28 | 1992-03-31 | Nellcor Incorporated | Perinatal pulse oximetry probe |
CA1331483C (en) | 1988-11-02 | 1994-08-16 | Britton Chance | User-wearable hemoglobinometer for measuring the metabolic condition of a subject |
US5122974A (en) | 1989-02-06 | 1992-06-16 | Nim, Inc. | Phase modulated spectrophotometry |
US4972331A (en) | 1989-02-06 | 1990-11-20 | Nim, Inc. | Phase modulated spectrophotometry |
US5873821A (en) | 1992-05-18 | 1999-02-23 | Non-Invasive Technology, Inc. | Lateralization spectrophotometer |
US5564417A (en) | 1991-01-24 | 1996-10-15 | Non-Invasive Technology, Inc. | Pathlength corrected oximeter and the like |
USH1039H (en) | 1988-11-14 | 1992-04-07 | The United States Of America As Represented By The Secretary Of The Air Force | Intrusion-free physiological condition monitoring |
EP0374668A3 (en) | 1988-12-16 | 1992-02-05 | A.W. Faber - Castell GmbH & Co. | Fluorescent marking fluid |
JPH02164341A (en) | 1988-12-19 | 1990-06-25 | Nippon Koden Corp | Hemoglobin concentration measuring device |
US5353799A (en) | 1991-01-22 | 1994-10-11 | Non Invasive Technology, Inc. | Examination of subjects using photon migration with high directionality techniques |
US5553614A (en) | 1988-12-21 | 1996-09-10 | Non-Invasive Technology, Inc. | Examination of biological tissue using frequency domain spectroscopy |
US5119815A (en) | 1988-12-21 | 1992-06-09 | Nim, Incorporated | Apparatus for determining the concentration of a tissue pigment of known absorbance, in vivo, using the decay characteristics of scintered electromagnetic radiation |
US5111817A (en) | 1988-12-29 | 1992-05-12 | Medical Physics, Inc. | Noninvasive system and method for enhanced arterial oxygen saturation determination and arterial blood pressure monitoring |
US5028787A (en) | 1989-01-19 | 1991-07-02 | Futrex, Inc. | Non-invasive measurement of blood glucose |
US5365066A (en) | 1989-01-19 | 1994-11-15 | Futrex, Inc. | Low cost means for increasing measurement sensitivity in LED/IRED near-infrared instruments |
US6708048B1 (en) | 1989-02-06 | 2004-03-16 | Non-Invasive Technology, Inc. | Phase modulation spectrophotometric apparatus |
US6183414B1 (en) | 1999-04-26 | 2001-02-06 | Michael S. Wysor | Technique for restoring plasticity to tissues of a male or female organ |
FI82366C (en) | 1989-02-06 | 1991-03-11 | Instrumentarium Oy | MAETNING AV BLODETS SAMMANSAETTNING. |
US5596986A (en) | 1989-03-17 | 1997-01-28 | Scico, Inc. | Blood oximeter |
US5902235A (en) | 1989-03-29 | 1999-05-11 | Somanetics Corporation | Optical cerebral oximeter |
DE3912993C2 (en) | 1989-04-20 | 1998-01-29 | Nicolay Gmbh | Optoelectronic sensor for generating electrical signals based on physiological values |
US5040539A (en) | 1989-05-12 | 1991-08-20 | The United States Of America | Pulse oximeter for diagnosis of dental pulp pathology |
JP2766317B2 (en) | 1989-06-22 | 1998-06-18 | コーリン電子株式会社 | Pulse oximeter |
US5090410A (en) | 1989-06-28 | 1992-02-25 | Datascope Investment Corp. | Fastener for attaching sensor to the body |
JPH0315502U (en) | 1989-06-28 | 1991-02-15 | ||
US5299120A (en) | 1989-09-15 | 1994-03-29 | Hewlett-Packard Company | Method for digitally processing signals containing information regarding arterial blood flow |
US5058588A (en) | 1989-09-19 | 1991-10-22 | Hewlett-Packard Company | Oximeter and medical sensor therefor |
US5483646A (en) | 1989-09-29 | 1996-01-09 | Kabushiki Kaisha Toshiba | Memory access control method and system for realizing the same |
US5216598A (en) | 1989-10-04 | 1993-06-01 | Colin Electronics Co., Ltd. | System for correction of trends associated with pulse wave forms in oximeters |
US5007423A (en) | 1989-10-04 | 1991-04-16 | Nippon Colin Company Ltd. | Oximeter sensor temperature control |
US5203329A (en) | 1989-10-05 | 1993-04-20 | Colin Electronics Co., Ltd. | Noninvasive reflectance oximeter sensor providing controlled minimum optical detection depth |
US5094239A (en) | 1989-10-05 | 1992-03-10 | Colin Electronics Co., Ltd. | Composite signal implementation for acquiring oximetry signals |
US5190038A (en) | 1989-11-01 | 1993-03-02 | Novametrix Medical Systems, Inc. | Pulse oximeter with improved accuracy and response time |
DE3938759A1 (en) | 1989-11-23 | 1991-05-29 | Philips Patentverwaltung | NON-INVASIVE OXIMETER ARRANGEMENT |
US5224478A (en) | 1989-11-25 | 1993-07-06 | Colin Electronics Co., Ltd. | Reflecting-type oxymeter probe |
KR100213554B1 (en) | 1989-11-28 | 1999-08-02 | 제이슨 오토 가도시 | Fetal probe |
EP0613652B1 (en) | 1990-02-15 | 1997-04-16 | Hewlett-Packard GmbH | Apparatus and method for non-invasive measurement of oxygen saturation |
US5152296A (en) | 1990-03-01 | 1992-10-06 | Hewlett-Packard Company | Dual-finger vital signs monitor |
US5104623A (en) | 1990-04-03 | 1992-04-14 | Minnesota Mining And Manufacturing Company | Apparatus and assembly for use in optically sensing a compositional blood parameter |
US5066859A (en) | 1990-05-18 | 1991-11-19 | Karkar Maurice N | Hematocrit and oxygen saturation blood analyzer |
GB9011887D0 (en) | 1990-05-26 | 1990-07-18 | Le Fit Ltd | Pulse responsive device |
WO1991018549A1 (en) | 1990-05-29 | 1991-12-12 | Yue Samuel K | Fetal probe apparatus |
US5239185A (en) | 1990-06-22 | 1993-08-24 | Hitachi, Ltd. | Method and equipment for measuring absorptance of light scattering materials using plural wavelengths of light |
US5259761A (en) | 1990-08-06 | 1993-11-09 | Jenifer M. Schnettler | Tooth vitality probe and process |
ES2128297T3 (en) | 1990-08-22 | 1999-05-16 | Nellcor Puritan Bennett Inc | APPARATUS FOR THE OXIMETRY OF THE PULSE OF A FETUS. |
US5158082A (en) | 1990-08-23 | 1992-10-27 | Spacelabs, Inc. | Apparatus for heating tissue with a photoplethysmograph sensor |
AU8411691A (en) | 1990-08-29 | 1992-03-30 | Theodore E. Cadell | Finger receptor |
US5170786A (en) | 1990-09-28 | 1992-12-15 | Novametrix Medical Systems, Inc. | Reusable probe system |
US5055671A (en) | 1990-10-03 | 1991-10-08 | Spacelabs, Inc. | Apparatus for detecting transducer movement using a first and second light detector |
US6266546B1 (en) | 1990-10-06 | 2001-07-24 | In-Line Diagnostics Corporation | System for noninvasive hematocrit monitoring |
US6246894B1 (en) | 1993-02-01 | 2001-06-12 | In-Line Diagnostics Corporation | System and method for measuring blood urea nitrogen, blood osmolarity, plasma free hemoglobin and tissue water content |
US5372136A (en) | 1990-10-06 | 1994-12-13 | Noninvasive Medical Technology Corporation | System and method for noninvasive hematocrit monitoring |
US6681128B2 (en) | 1990-10-06 | 2004-01-20 | Hema Metrics, Inc. | System for noninvasive hematocrit monitoring |
US5209230A (en) | 1990-10-19 | 1993-05-11 | Nellcor Incorporated | Adhesive pulse oximeter sensor with reusable portion |
US6263221B1 (en) | 1991-01-24 | 2001-07-17 | Non-Invasive Technology | Quantitative analyses of biological tissue using phase modulation spectroscopy |
US5193542A (en) | 1991-01-28 | 1993-03-16 | Missanelli John S | Peripartum oximetric monitoring apparatus |
US5291884A (en) | 1991-02-07 | 1994-03-08 | Minnesota Mining And Manufacturing Company | Apparatus for measuring a blood parameter |
US5125403A (en) | 1991-02-20 | 1992-06-30 | Culp Joel B | Device and method for engagement of an oximeter probe |
US5154175A (en) | 1991-03-04 | 1992-10-13 | Gunther Ted J | Intrauterine fetal EKG-oximetry cable apparatus |
US5349953A (en) | 1991-03-05 | 1994-09-27 | Sensormedics, Corp. | Photoplethysmographics using component-amplitude-division multiplexing |
US5343818A (en) | 1991-03-05 | 1994-09-06 | Sensormedics Corp. | Photoplethysmographics using energy-reducing waveform shaping |
US5349952A (en) | 1991-03-05 | 1994-09-27 | Sensormedics Corp. | Photoplethysmographics using phase-division multiplexing |
US5490505A (en) | 1991-03-07 | 1996-02-13 | Masimo Corporation | Signal processing apparatus |
US5632272A (en) | 1991-03-07 | 1997-05-27 | Masimo Corporation | Signal processing apparatus |
WO1992015955A1 (en) | 1991-03-07 | 1992-09-17 | Vital Signals, Inc. | Signal processing apparatus and method |
MX9702434A (en) | 1991-03-07 | 1998-05-31 | Masimo Corp | Signal processing apparatus. |
US5226417A (en) | 1991-03-11 | 1993-07-13 | Nellcor, Inc. | Apparatus for the detection of motion transients |
US5237994A (en) | 1991-03-12 | 1993-08-24 | Square One Technology | Integrated lead frame pulse oximetry sensor |
US6580086B1 (en) | 1999-08-26 | 2003-06-17 | Masimo Corporation | Shielded optical probe and method |
US5638818A (en) | 1991-03-21 | 1997-06-17 | Masimo Corporation | Low noise optical probe |
US6541756B2 (en) | 1991-03-21 | 2003-04-01 | Masimo Corporation | Shielded optical probe having an electrical connector |
US5645440A (en) | 1995-10-16 | 1997-07-08 | Masimo Corporation | Patient cable connector |
US5995855A (en) | 1998-02-11 | 1999-11-30 | Masimo Corporation | Pulse oximetry sensor adapter |
DE4138702A1 (en) | 1991-03-22 | 1992-09-24 | Madaus Medizin Elektronik | METHOD AND DEVICE FOR THE DIAGNOSIS AND QUANTITATIVE ANALYSIS OF APNOE AND FOR THE SIMULTANEOUS DETERMINATION OF OTHER DISEASES |
US5273036A (en) | 1991-04-03 | 1993-12-28 | Ppg Industries, Inc. | Apparatus and method for monitoring respiration |
US5218962A (en) | 1991-04-15 | 1993-06-15 | Nellcor Incorporated | Multiple region pulse oximetry probe and oximeter |
US5247932A (en) | 1991-04-15 | 1993-09-28 | Nellcor Incorporated | Sensor for intrauterine use |
US5313940A (en) | 1991-05-15 | 1994-05-24 | Nihon Kohden Corporation | Photo-electric pulse wave measuring probe |
US6549795B1 (en) | 1991-05-16 | 2003-04-15 | Non-Invasive Technology, Inc. | Spectrophotometer for tissue examination |
US5267563A (en) | 1991-06-28 | 1993-12-07 | Nellcor Incorporated | Oximeter sensor with perfusion enhancing |
US5402777A (en) | 1991-06-28 | 1995-04-04 | Alza Corporation | Methods and devices for facilitated non-invasive oxygen monitoring |
DE69227545T2 (en) | 1991-07-12 | 1999-04-29 | Mark R Robinson | Oximeter for the reliable clinical determination of blood oxygen saturation in a fetus |
US5413100A (en) | 1991-07-17 | 1995-05-09 | Effets Biologiques Exercice | Non-invasive method for the in vivo determination of the oxygen saturation rate of arterial blood, and device for carrying out the method |
US5351685A (en) | 1991-08-05 | 1994-10-04 | Nellcor Incorporated | Condensed oximeter system with noise reduction software |
EP0527703B1 (en) | 1991-08-12 | 1995-06-28 | AVL Medical Instruments AG | Device for measuring at least one gaseous concentration level in particular the oxygen concentration level in blood |
US5368025A (en) | 1991-08-22 | 1994-11-29 | Sensor Devices, Inc. | Non-invasive oximeter probe |
US5217012A (en) | 1991-08-22 | 1993-06-08 | Sensor Devices Inc. | Noninvasive oximeter probe |
US5429129A (en) | 1991-08-22 | 1995-07-04 | Sensor Devices, Inc. | Apparatus for determining spectral absorption by a specific substance in a fluid |
US5246003A (en) | 1991-08-28 | 1993-09-21 | Nellcor Incorporated | Disposable pulse oximeter sensor |
US6714803B1 (en) | 1991-09-03 | 2004-03-30 | Datex-Ohmeda, Inc. | Pulse oximetry SpO2 determination |
US5934277A (en) | 1991-09-03 | 1999-08-10 | Datex-Ohmeda, Inc. | System for pulse oximetry SpO2 determination |
US5247931A (en) | 1991-09-16 | 1993-09-28 | Mine Safety Appliances Company | Diagnostic sensor clasp utilizing a slot, pivot and spring hinge mechanism |
US5213099A (en) | 1991-09-30 | 1993-05-25 | The United States Of America As Represented By The Secretary Of The Air Force | Ear canal pulse/oxygen saturation measuring device |
US5249576A (en) | 1991-10-24 | 1993-10-05 | Boc Health Care, Inc. | Universal pulse oximeter probe |
US5311865A (en) | 1991-11-07 | 1994-05-17 | Mayeux Charles D | Plastic finger oximetry probe holder |
US5253645A (en) | 1991-12-13 | 1993-10-19 | Critikon, Inc. | Method of producing an audible alarm in a blood pressure and pulse oximeter monitor |
JPH0569784U (en) | 1991-12-28 | 1993-09-21 | センチュリーメディカル株式会社 | Display device in medical equipment |
EP0549835B1 (en) | 1991-12-30 | 1996-03-13 | Hamamatsu Photonics K.K. | Diagnostic apparatus |
EP0553372B1 (en) | 1992-01-29 | 1996-11-13 | Hewlett-Packard GmbH | Method and system for monitoring vital signs |
US5385143A (en) | 1992-02-06 | 1995-01-31 | Nihon Kohden Corporation | Apparatus for measuring predetermined data of living tissue |
US5297548A (en) | 1992-02-07 | 1994-03-29 | Ohmeda Inc. | Arterial blood monitoring probe |
US5246002A (en) | 1992-02-11 | 1993-09-21 | Physio-Control Corporation | Noise insensitive pulse transmittance oximeter |
JP3249517B2 (en) | 1992-02-28 | 2002-01-21 | キャデル、テオドール・イー | Non-invasive device and method for determining the concentration of various components of blood or tissue |
US5263244A (en) | 1992-04-17 | 1993-11-23 | Gould Inc. | Method of making a flexible printed circuit sensor assembly for detecting optical pulses |
EP0572684B1 (en) | 1992-05-15 | 1996-07-03 | Hewlett-Packard GmbH | Medical sensor |
US6785568B2 (en) | 1992-05-18 | 2004-08-31 | Non-Invasive Technology Inc. | Transcranial examination of the brain |
JP3091929B2 (en) | 1992-05-28 | 2000-09-25 | 日本光電工業株式会社 | Pulse oximeter |
JP3165983B2 (en) | 1992-06-15 | 2001-05-14 | 日本光電工業株式会社 | Light emitting element driving device for pulse oximeter |
US5377675A (en) | 1992-06-24 | 1995-01-03 | Nellcor, Inc. | Method and apparatus for improved fetus contact with fetal probe |
US5355880A (en) | 1992-07-06 | 1994-10-18 | Sandia Corporation | Reliable noninvasive measurement of blood gases |
JP3116252B2 (en) | 1992-07-09 | 2000-12-11 | 日本光電工業株式会社 | Pulse oximeter |
US6222189B1 (en) | 1992-07-15 | 2001-04-24 | Optix, Lp | Methods of enhancing optical signals by mechanical manipulation in non-invasive testing |
US6411832B1 (en) | 1992-07-15 | 2002-06-25 | Optix Lp | Method of improving reproducibility of non-invasive measurements |
US5425360A (en) | 1992-07-24 | 1995-06-20 | Sensormedics Corporation | Molded pulse oximeter sensor |
US20050062609A9 (en) | 1992-08-19 | 2005-03-24 | Lynn Lawrence A. | Pulse oximetry relational alarm system for early recognition of instability and catastrophic occurrences |
US5680857A (en) | 1992-08-28 | 1997-10-28 | Spacelabs Medical, Inc. | Alignment guide system for transmissive pulse oximetry sensors |
US5348003A (en) | 1992-09-03 | 1994-09-20 | Sirraya, Inc. | Method and apparatus for chemical analysis |
JP2547840Y2 (en) | 1992-09-25 | 1997-09-17 | 日本光電工業株式会社 | Oximeter probe |
US5323776A (en) | 1992-10-15 | 1994-06-28 | Picker International, Inc. | MRI compatible pulse oximetry system |
US5329922A (en) | 1992-10-19 | 1994-07-19 | Atlee Iii John L | Oximetric esophageal probe |
US5368224A (en) | 1992-10-23 | 1994-11-29 | Nellcor Incorporated | Method for reducing ambient noise effects in electronic monitoring instruments |
EP0690692A4 (en) | 1992-12-01 | 1999-02-10 | Somanetics Corp | Patient sensor for optical cerebral oximeters |
US5287853A (en) | 1992-12-11 | 1994-02-22 | Hewlett-Packard Company | Adapter cable for connecting a pulsoximetry sensor unit to a medical measuring device |
US5551423A (en) | 1993-01-26 | 1996-09-03 | Nihon Kohden Corporation | Pulse oximeter probe |
DE4304693C2 (en) | 1993-02-16 | 2002-02-21 | Gerhard Rall | Sensor device for measuring vital parameters of a fetus during childbirth |
EP0615723A1 (en) | 1993-03-04 | 1994-09-21 | Hamamatsu Photonics K.K. | Method and apparatus for measuring blood flow |
JP2586392Y2 (en) | 1993-03-15 | 1998-12-02 | 日本光電工業株式会社 | Probe for pulse oximeter |
US5687719A (en) | 1993-03-25 | 1997-11-18 | Ikuo Sato | Pulse oximeter probe |
US5368026A (en) | 1993-03-26 | 1994-11-29 | Nellcor Incorporated | Oximeter with motion detection for alarm modification |
US5520177A (en) | 1993-03-26 | 1996-05-28 | Nihon Kohden Corporation | Oximeter probe |
US5348004A (en) | 1993-03-31 | 1994-09-20 | Nellcor Incorporated | Electronic processor for pulse oximeter |
US5676141A (en) | 1993-03-31 | 1997-10-14 | Nellcor Puritan Bennett Incorporated | Electronic processor for pulse oximeters |
US5497771A (en) | 1993-04-02 | 1996-03-12 | Mipm Mammendorfer Institut Fuer Physik Und Medizin Gmbh | Apparatus for measuring the oxygen saturation of fetuses during childbirth |
US5521851A (en) | 1993-04-26 | 1996-05-28 | Nihon Kohden Corporation | Noise reduction method and apparatus |
US5339810A (en) | 1993-05-03 | 1994-08-23 | Marquette Electronics, Inc. | Pulse oximetry sensor |
AU7170094A (en) | 1993-05-20 | 1994-12-20 | Somanetics Corporation | Improved electro-optical sensor for spectrophotometric medical devices |
AU6942494A (en) | 1993-05-21 | 1994-12-20 | Nims, Inc. | Discriminating between valid and artifactual pulse waveforms |
WO1994027493A1 (en) | 1993-05-28 | 1994-12-08 | Somanetics Corporation | Method and apparatus for spectrophotometric cerebral oximetry |
JP3310390B2 (en) | 1993-06-10 | 2002-08-05 | 浜松ホトニクス株式会社 | Method and apparatus for measuring concentration of light absorbing substance in scattering medium |
US5337744A (en) | 1993-07-14 | 1994-08-16 | Masimo Corporation | Low noise finger cot probe |
US5452717A (en) | 1993-07-14 | 1995-09-26 | Masimo Corporation | Finger-cot probe |
US5425362A (en) | 1993-07-30 | 1995-06-20 | Criticare | Fetal sensor device |
EP0641543A1 (en) | 1993-09-07 | 1995-03-08 | Ohmeda Inc. | Heat-sealed neo-natal medical monitoring probe |
JP3345481B2 (en) | 1993-09-22 | 2002-11-18 | 興和株式会社 | Pulse wave spectrometer |
JP3387171B2 (en) | 1993-09-28 | 2003-03-17 | セイコーエプソン株式会社 | Pulse wave detection device and exercise intensity measurement device |
US5485847A (en) | 1993-10-08 | 1996-01-23 | Nellcor Puritan Bennett Incorporated | Pulse oximeter using a virtual trigger for heart rate synchronization |
US5411023A (en) | 1993-11-24 | 1995-05-02 | The Shielding Corporation | Optical sensor system |
US5417207A (en) | 1993-12-06 | 1995-05-23 | Sensor Devices, Inc. | Apparatus for the invasive use of oximeter probes |
JP3125079B2 (en) | 1993-12-07 | 2001-01-15 | 日本光電工業株式会社 | Pulse oximeter |
DE69305178T2 (en) | 1993-12-11 | 1997-02-13 | Hewlett Packard Gmbh | Method for detecting an abnormal condition in a pulse powered oximeter system |
CA2155932A1 (en) | 1993-12-14 | 1995-06-22 | Tadakazu Yamauchi | Medical measuring apparatus |
US5438986A (en) | 1993-12-14 | 1995-08-08 | Criticare Systems, Inc. | Optical sensor |
US5411024A (en) | 1993-12-15 | 1995-05-02 | Corometrics Medical Systems, Inc. | Fetal pulse oximetry sensor |
US5492118A (en) | 1993-12-16 | 1996-02-20 | Board Of Trustees Of The University Of Illinois | Determining material concentrations in tissues |
US5645059A (en) | 1993-12-17 | 1997-07-08 | Nellcor Incorporated | Medical sensor with modulated encoding scheme |
US5560355A (en) | 1993-12-17 | 1996-10-01 | Nellcor Puritan Bennett Incorporated | Medical sensor with amplitude independent output |
JP3464697B2 (en) | 1993-12-21 | 2003-11-10 | 興和株式会社 | Oxygen saturation meter |
US5507286A (en) | 1993-12-23 | 1996-04-16 | Medical Taping Systems, Inc. | Method and apparatus for improving the durability of a sensor |
US5553615A (en) | 1994-01-31 | 1996-09-10 | Minnesota Mining And Manufacturing Company | Method and apparatus for noninvasive prediction of hematocrit |
US5437275A (en) | 1994-02-02 | 1995-08-01 | Biochem International Inc. | Pulse oximetry sensor |
US5632273A (en) | 1994-02-04 | 1997-05-27 | Hamamatsu Photonics K.K. | Method and means for measurement of biochemical components |
US5995859A (en) | 1994-02-14 | 1999-11-30 | Nihon Kohden Corporation | Method and apparatus for accurately measuring the saturated oxygen in arterial blood by substantially eliminating noise from the measurement signal |
US5830135A (en) | 1994-03-31 | 1998-11-03 | Bosque; Elena M. | Fuzzy logic alarm system for pulse oximeters |
US5421329A (en) | 1994-04-01 | 1995-06-06 | Nellcor, Inc. | Pulse oximeter sensor optimized for low saturation |
US6662033B2 (en) | 1994-04-01 | 2003-12-09 | Nellcor Incorporated | Pulse oximeter and sensor optimized for low saturation |
US5575284A (en) | 1994-04-01 | 1996-11-19 | University Of South Florida | Portable pulse oximeter |
JP3364819B2 (en) | 1994-04-28 | 2003-01-08 | 日本光電工業株式会社 | Blood absorption substance concentration measurement device |
US5491299A (en) | 1994-06-03 | 1996-02-13 | Siemens Medical Systems, Inc. | Flexible multi-parameter cable |
US5490523A (en) | 1994-06-29 | 1996-02-13 | Nonin Medical Inc. | Finger clip pulse oximeter |
US5912656A (en) | 1994-07-01 | 1999-06-15 | Ohmeda Inc. | Device for producing a display from monitored data |
DE4423597C1 (en) | 1994-07-06 | 1995-08-10 | Hewlett Packard Gmbh | Pulsoximetric ear sensor |
DE4429758A1 (en) | 1994-08-22 | 1996-02-29 | Buschmann Johannes | Method for validating devices for photometry of living tissue and device for carrying out the method |
DE4429845C1 (en) | 1994-08-23 | 1995-10-19 | Hewlett Packard Gmbh | Pulse oximeter with flexible strap for attachment to hand or foot |
US5697367A (en) | 1994-10-14 | 1997-12-16 | Somanetics Corporation | Specially grounded sensor for clinical spectrophotometric procedures |
US5503148A (en) | 1994-11-01 | 1996-04-02 | Ohmeda Inc. | System for pulse oximetry SPO2 determination |
DE4442260C2 (en) | 1994-11-28 | 2000-06-08 | Mipm Mammendorfer Inst Fuer Ph | Method and arrangement for the non-invasive in vivo determination of oxygen saturation |
DE4442855B4 (en) | 1994-12-01 | 2004-04-01 | Gerhard Dipl.-Ing. Rall | Use of a pulse oximetry sensor device |
US5505199A (en) | 1994-12-01 | 1996-04-09 | Kim; Bill H. | Sudden infant death syndrome monitor |
US5676139A (en) | 1994-12-14 | 1997-10-14 | Ohmeda Inc. | Spring clip probe housing |
US5673692A (en) | 1995-02-03 | 1997-10-07 | Biosignals Ltd. Co. | Single site, multi-variable patient monitor |
US5692503A (en) | 1995-03-10 | 1997-12-02 | Kuenstner; J. Todd | Method for noninvasive (in-vivo) total hemoglobin, oxyhemogolobin, deoxyhemoglobin, carboxyhemoglobin and methemoglobin concentration determination |
US5524617A (en) | 1995-03-14 | 1996-06-11 | Nellcor, Incorporated | Isolated layer pulse oximetry |
US5619992A (en) | 1995-04-06 | 1997-04-15 | Guthrie; Robert B. | Methods and apparatus for inhibiting contamination of reusable pulse oximetry sensors |
US5617852A (en) | 1995-04-06 | 1997-04-08 | Macgregor; Alastair R. | Method and apparatus for non-invasively determining blood analytes |
US5774213A (en) | 1995-04-21 | 1998-06-30 | Trebino; Rick P. | Techniques for measuring difference of an optical property at two wavelengths by modulating two sources to have opposite-phase components at a common frequency |
JP3326580B2 (en) | 1995-05-08 | 2002-09-24 | 日本光電工業株式会社 | Biological tissue transmitted light sensor |
US5662105A (en) | 1995-05-17 | 1997-09-02 | Spacelabs Medical, Inc. | System and method for the extractment of physiological signals |
US7035697B1 (en) | 1995-05-30 | 2006-04-25 | Roy-G-Biv Corporation | Access control systems and methods for motion control |
US5851178A (en) | 1995-06-02 | 1998-12-22 | Ohmeda Inc. | Instrumented laser diode probe connector |
US5638816A (en) | 1995-06-07 | 1997-06-17 | Masimo Corporation | Active pulse blood constituent monitoring |
US5758644A (en) | 1995-06-07 | 1998-06-02 | Masimo Corporation | Manual and automatic probe calibration |
US5760910A (en) | 1995-06-07 | 1998-06-02 | Masimo Corporation | Optical filter for spectroscopic measurement and method of producing the optical filter |
US5634461A (en) * | 1995-06-07 | 1997-06-03 | Alliance Pharmaceutical Corp. | System for measuring blood oxygen levels |
AU708051B2 (en) | 1995-06-09 | 1999-07-29 | Conmed Israel Ltd | Sensor, method and device for optical blood oximetry |
US5645060A (en) | 1995-06-14 | 1997-07-08 | Nellcor Puritan Bennett Incorporated | Method and apparatus for removing artifact and noise from pulse oximetry |
US5685301A (en) | 1995-06-16 | 1997-11-11 | Ohmeda Inc. | Apparatus for precise determination of operating characteristics of optical devices contained in a monitoring probe |
WO1997003603A1 (en) | 1995-07-21 | 1997-02-06 | Respironics, Inc. | Method and apparatus for diode laser pulse oximetry using multifiber optical cables and disposable fiber optic probes |
US5558096A (en) | 1995-07-21 | 1996-09-24 | Biochem International, Inc. | Blood pulse detection method using autocorrelation |
US6095974A (en) | 1995-07-21 | 2000-08-01 | Respironics, Inc. | Disposable fiber optic probe |
GB9515649D0 (en) | 1995-07-31 | 1995-09-27 | Johnson & Johnson Medical | Surface sensor device |
US5853364A (en) | 1995-08-07 | 1998-12-29 | Nellcor Puritan Bennett, Inc. | Method and apparatus for estimating physiological parameters using model-based adaptive filtering |
US5800348A (en) | 1995-08-31 | 1998-09-01 | Hewlett-Packard Company | Apparatus and method for medical monitoring, in particular pulse oximeter |
DE19537646C2 (en) | 1995-10-10 | 1998-09-17 | Hewlett Packard Gmbh | Method and device for detecting falsified measurement values in pulse oximetry for measuring oxygen saturation |
USD393830S (en) | 1995-10-16 | 1998-04-28 | Masimo Corporation | Patient cable connector |
US5626140A (en) | 1995-11-01 | 1997-05-06 | Spacelabs Medical, Inc. | System and method of multi-sensor fusion of physiological measurements |
DE19541605C2 (en) | 1995-11-08 | 1999-06-24 | Hewlett Packard Co | Sensor and method for performing medical measurements, in particular pulse oximetric measurements, on the human finger |
US5839439A (en) | 1995-11-13 | 1998-11-24 | Nellcor Puritan Bennett Incorporated | Oximeter sensor with rigid inner housing and pliable overmold |
US5660567A (en) | 1995-11-14 | 1997-08-26 | Nellcor Puritan Bennett Incorporated | Medical sensor connector with removable encoding device |
US5588427A (en) | 1995-11-20 | 1996-12-31 | Spacelabs Medical, Inc. | Enhancement of physiological signals using fractal analysis |
US5724967A (en) | 1995-11-21 | 1998-03-10 | Nellcor Puritan Bennett Incorporated | Noise reduction apparatus for low level analog signals |
US5995856A (en) | 1995-11-22 | 1999-11-30 | Nellcor, Incorporated | Non-contact optical monitoring of physiological parameters |
US6041247A (en) | 1995-11-29 | 2000-03-21 | Instrumentarium Corp | Non-invasive optical measuring sensor and measuring method |
US5810724A (en) | 1995-12-01 | 1998-09-22 | Nellcor Puritan Bennett Incorporated | Reusable sensor accessory containing a conformable spring activated rubber sleeved clip |
DE19651690C2 (en) | 1995-12-13 | 2001-12-13 | Bernreuter Peter | Measuring method for determining blood oxygen saturation |
US6226540B1 (en) | 1995-12-13 | 2001-05-01 | Peter Bernreuter | Measuring process for blood gas analysis sensors |
US20020014533A1 (en) | 1995-12-18 | 2002-02-07 | Xiaxun Zhu | Automated object dimensioning system employing contour tracing, vertice detection, and forner point detection and reduction methods on 2-d range data maps |
US5807247A (en) | 1995-12-20 | 1998-09-15 | Nellcor Puritan Bennett Incorporated | Method and apparatus for facilitating compatibility between pulse oximeters and sensor probes |
US5818985A (en) | 1995-12-20 | 1998-10-06 | Nellcor Puritan Bennett Incorporated | Optical oximeter probe adapter |
AUPN740796A0 (en) | 1996-01-04 | 1996-01-25 | Circuitry Systems Limited | Biomedical data collection apparatus |
US5891026A (en) | 1996-01-29 | 1999-04-06 | Ntc Technology Inc. | Extended life disposable pulse oximetry sensor and method of making |
SE9600322L (en) | 1996-01-30 | 1997-07-31 | Hoek Instr Ab | Sensor for pulse oximetry with fiber optic signal transmission |
US5746697A (en) | 1996-02-09 | 1998-05-05 | Nellcor Puritan Bennett Incorporated | Medical diagnostic apparatus with sleep mode |
US5797841A (en) | 1996-03-05 | 1998-08-25 | Nellcor Puritan Bennett Incorporated | Shunt barrier in pulse oximeter sensor |
US6253097B1 (en) | 1996-03-06 | 2001-06-26 | Datex-Ohmeda, Inc. | Noninvasive medical monitoring instrument using surface emitting laser devices |
DE59704665D1 (en) | 1996-04-01 | 2001-10-25 | Linde Medical Sensors Ag Basel | DETECTION OF INTERFERENCE SIGNALS IN PULSOXYMETRIC MEASUREMENT |
US5790729A (en) | 1996-04-10 | 1998-08-04 | Ohmeda Inc. | Photoplethysmographic instrument having an integrated multimode optical coupler device |
US5766127A (en) | 1996-04-15 | 1998-06-16 | Ohmeda Inc. | Method and apparatus for improved photoplethysmographic perfusion-index monitoring |
US5692505A (en) | 1996-04-25 | 1997-12-02 | Fouts; James Michael | Data processing systems and methods for pulse oximeters |
US5913819A (en) | 1996-04-26 | 1999-06-22 | Datex-Ohmeda, Inc. | Injection molded, heat-sealed housing and half-etched lead frame for oximeter sensor |
US5919133A (en) | 1996-04-26 | 1999-07-06 | Ohmeda Inc. | Conformal wrap for pulse oximeter sensor |
WO1997042903A1 (en) | 1996-05-15 | 1997-11-20 | Nellcor Puritan Bennett Incorporated | Semi-reusable sensor with disposable sleeve |
US5807248A (en) | 1996-05-15 | 1998-09-15 | Ohmeda Inc. | Medical monitoring probe with modular device housing |
US5752914A (en) | 1996-05-28 | 1998-05-19 | Nellcor Puritan Bennett Incorporated | Continuous mesh EMI shield for pulse oximetry sensor |
FI962448A (en) | 1996-06-12 | 1997-12-13 | Instrumentarium Oy | Method, apparatus and sensor for the determination of fractional oxygen saturation |
US5890929A (en) | 1996-06-19 | 1999-04-06 | Masimo Corporation | Shielded medical connector |
US5879294A (en) | 1996-06-28 | 1999-03-09 | Hutchinson Technology Inc. | Tissue chromophore measurement system |
US5842981A (en) | 1996-07-17 | 1998-12-01 | Criticare Systems, Inc. | Direct to digital oximeter |
US6163715A (en) | 1996-07-17 | 2000-12-19 | Criticare Systems, Inc. | Direct to digital oximeter and method for calculating oxygenation levels |
ATE346539T1 (en) | 1996-07-19 | 2006-12-15 | Daedalus I Llc | DEVICE FOR THE BLOODLESS DETERMINATION OF BLOOD VALUES |
EP0914601B1 (en) | 1996-07-26 | 2002-05-08 | Linde Medical Sensors AG | Method of non-invasive determination of oxygen saturation in tissue in which blood is circulating |
US5916155A (en) | 1996-07-30 | 1999-06-29 | Nellcor Puritan Bennett Incorporated | Fetal sensor with securing balloons remote from optics |
US5842982A (en) | 1996-08-07 | 1998-12-01 | Nellcor Puritan Bennett Incorporated | Infant neonatal pulse oximeter sensor |
US5813980A (en) | 1996-08-13 | 1998-09-29 | Nellcor Puritan Bennett Incorporated | Fetal pulse oximetry sensor with remote securing mechanism |
US5776058A (en) | 1996-08-13 | 1998-07-07 | Nellcor Puritan Bennett Incorporated | Pressure-attached presenting part fetal pulse oximetry sensor |
US5823952A (en) | 1996-08-14 | 1998-10-20 | Nellcor Incorporated | Pulse oximeter sensor with differential slip coefficient |
JP3844815B2 (en) | 1996-08-30 | 2006-11-15 | 浜松ホトニクス株式会社 | Method and apparatus for measuring absorption information of scatterers |
US5727547A (en) | 1996-09-04 | 1998-03-17 | Nellcor Puritan Bennett Incorporated | Presenting part fetal oximeter sensor with securing mechanism for providing tension to scalp attachment |
US5830139A (en) | 1996-09-04 | 1998-11-03 | Abreu; Marcio M. | Tonometer system for measuring intraocular pressure by applanation and/or indentation |
US6544193B2 (en) | 1996-09-04 | 2003-04-08 | Marcio Marc Abreu | Noninvasive measurement of chemical substances |
US6120460A (en) | 1996-09-04 | 2000-09-19 | Abreu; Marcio Marc | Method and apparatus for signal acquisition, processing and transmission for evaluation of bodily functions |
US5871442A (en) | 1996-09-10 | 1999-02-16 | International Diagnostics Technologies, Inc. | Photonic molecular probe |
US6081742A (en) | 1996-09-10 | 2000-06-27 | Seiko Epson Corporation | Organism state measuring device and relaxation instructing device |
US5782756A (en) | 1996-09-19 | 1998-07-21 | Nellcor Puritan Bennett Incorporated | Method and apparatus for in vivo blood constituent analysis |
US5782758A (en) | 1996-09-23 | 1998-07-21 | Ohmeda Inc. | Method and apparatus for identifying the presence of noise in a time division multiplexed oximeter |
US5891022A (en) | 1996-09-25 | 1999-04-06 | Ohmeda Inc. | Apparatus for performing multiwavelength photoplethysmography |
US6018673A (en) | 1996-10-10 | 2000-01-25 | Nellcor Puritan Bennett Incorporated | Motion compatible sensor for non-invasive optical blood analysis |
US5851179A (en) | 1996-10-10 | 1998-12-22 | Nellcor Puritan Bennett Incorporated | Pulse oximeter sensor with articulating head |
US5800349A (en) | 1996-10-15 | 1998-09-01 | Nonin Medical, Inc. | Offset pulse oximeter sensor |
JP3856477B2 (en) | 1996-10-24 | 2006-12-13 | マサチューセッツ・インスティテュート・オブ・テクノロジー | Patient monitoring ring sensor |
US5817008A (en) | 1996-10-31 | 1998-10-06 | Spacelabs Medical, Inc. | Conformal pulse oximetry sensor and monitor |
US5830136A (en) | 1996-10-31 | 1998-11-03 | Nellcor Puritan Bennett Incorporated | Gel pad optical sensor |
US5830137A (en) | 1996-11-18 | 1998-11-03 | University Of South Florida | Green light pulse oximeter |
US6397093B1 (en) | 1996-12-05 | 2002-05-28 | Essential Medical Devices, Inc. | Non-invasive carboxyhemoglobin analyzer |
US5810723A (en) | 1996-12-05 | 1998-09-22 | Essential Medical Devices | Non-invasive carboxyhemoglobin analyer |
US5921921A (en) | 1996-12-18 | 1999-07-13 | Nellcor Puritan-Bennett | Pulse oximeter with sigma-delta converter |
US5842979A (en) | 1997-02-14 | 1998-12-01 | Ohmeda Inc. | Method and apparatus for improved photoplethysmographic monitoring of oxyhemoglobin, deoxyhemoglobin, carboxyhemoglobin and methemoglobin |
US6113541A (en) | 1997-03-07 | 2000-09-05 | Agilent Technologies, Inc. | Noninvasive blood chemistry measurement method and system |
US6487439B1 (en) | 1997-03-17 | 2002-11-26 | Victor N. Skladnev | Glove-mounted hybrid probe for tissue type recognition |
US5954644A (en) | 1997-03-24 | 1999-09-21 | Ohmeda Inc. | Method for ambient light subtraction in a photoplethysmographic measurement instrument |
US5817010A (en) | 1997-03-25 | 1998-10-06 | Ohmeda Inc. | Disposable sensor holder |
WO1998043096A2 (en) | 1997-03-25 | 1998-10-01 | Siemens Aktiengesellschaft | Method and device for non-invasive in vivo determination of blood constituents |
US5827182A (en) | 1997-03-31 | 1998-10-27 | Ohmeda Inc. | Multiple LED sets in oximetry sensors |
US6195575B1 (en) | 1997-04-02 | 2001-02-27 | Nellcor Puritan Bennett Incorporated | Fetal sensor which self-inflates using capillary force |
US5891024A (en) | 1997-04-09 | 1999-04-06 | Ohmeda Inc. | Two stage calibration and analyte measurement scheme for spectrophotomeric analysis |
DE69704264T2 (en) | 1997-04-12 | 2001-06-28 | Agilent Technologies Inc | Method and device for the non-invasive determination of the concentration of a component |
EP0870466B1 (en) | 1997-04-12 | 1999-06-02 | Hewlett-Packard Company | Method and apparatus for determining the concentration of a component |
US5919134A (en) | 1997-04-14 | 1999-07-06 | Masimo Corp. | Method and apparatus for demodulating signals in a pulse oximetry system |
US6002952A (en) | 1997-04-14 | 1999-12-14 | Masimo Corporation | Signal processing apparatus and method |
US6229856B1 (en) | 1997-04-14 | 2001-05-08 | Masimo Corporation | Method and apparatus for demodulating signals in a pulse oximetry system |
EP0872210B1 (en) | 1997-04-18 | 2006-01-04 | Koninklijke Philips Electronics N.V. | Intermittent measuring of arterial oxygen saturation of hemoglobin |
AUPO676397A0 (en) | 1997-05-13 | 1997-06-05 | Dunlop, Colin | Method and apparatus for monitoring haemodynamic function |
IL121079A0 (en) | 1997-06-15 | 1997-11-20 | Spo Medical Equipment Ltd | Physiological stress detector device and method |
CA2303803A1 (en) | 1997-06-17 | 1998-12-23 | Respironics, Inc. | Fetal oximetry system and sensor |
AU7934498A (en) | 1997-06-27 | 1999-01-19 | Toa Medical Electronics Co., Ltd. | Living body inspecting apparatus and noninvasive blood analyzer using the same |
US5924985A (en) | 1997-07-29 | 1999-07-20 | Ohmeda Inc. | Patient probe disconnect alarm |
US6343223B1 (en) | 1997-07-30 | 2002-01-29 | Mallinckrodt Inc. | Oximeter sensor with offset emitters and detector and heating device |
US6115621A (en) | 1997-07-30 | 2000-09-05 | Nellcor Puritan Bennett Incorporated | Oximetry sensor with offset emitters and detector |
US6466808B1 (en) | 1999-11-22 | 2002-10-15 | Mallinckrodt Inc. | Single device for both heating and temperature measurement in an oximeter sensor |
US5924982A (en) | 1997-07-30 | 1999-07-20 | Nellcor Puritan Bennett Incorporated | Oximeter sensor with user-modifiable color surface |
US6018674A (en) | 1997-08-11 | 2000-01-25 | Datex-Ohmeda, Inc. | Fast-turnoff photodiodes with switched-gain preamplifiers in photoplethysmographic measurement instruments |
FI973454A (en) | 1997-08-22 | 1999-02-23 | Instrumentarium Oy | A resilient device in a measuring sensor for observing the properties of living tissue |
GB9717858D0 (en) | 1997-08-23 | 1997-10-29 | Electrode Company Ltd | The Electrode Company Ltd |
DE69833656T2 (en) | 1997-08-26 | 2006-08-17 | Seiko Epson Corp. | DEVICE FOR DIAGNOSIS OF PULSE WAVES |
EP0941694B1 (en) | 1997-09-05 | 2007-08-22 | Seiko Epson Corporation | Method for configuring a reflected light sensor |
GB2329015B (en) | 1997-09-05 | 2002-02-13 | Samsung Electronics Co Ltd | Method and device for noninvasive measurement of concentrations of blood components |
US5865736A (en) | 1997-09-30 | 1999-02-02 | Nellcor Puritan Bennett, Inc. | Method and apparatus for nuisance alarm reductions |
US5960610A (en) | 1997-10-01 | 1999-10-05 | Nellcor Puritan Bennett Incorporated | Method of curving a fetal sensor |
US5971930A (en) | 1997-10-17 | 1999-10-26 | Siemens Medical Systems, Inc. | Method and apparatus for removing artifact from physiological signals |
US5995858A (en) | 1997-11-07 | 1999-11-30 | Datascope Investment Corp. | Pulse oximeter |
US5987343A (en) | 1997-11-07 | 1999-11-16 | Datascope Investment Corp. | Method for storing pulse oximetry sensor characteristics |
US6035223A (en) | 1997-11-19 | 2000-03-07 | Nellcor Puritan Bennett Inc. | Method and apparatus for determining the state of an oximetry sensor |
AU1608099A (en) | 1997-11-26 | 1999-06-15 | Somanetics Corporation | Method and apparatus for monitoring fetal cerebral oxygenation during childbirth |
US5983122A (en) | 1997-12-12 | 1999-11-09 | Ohmeda Inc. | Apparatus and method for improved photoplethysmographic monitoring of multiple hemoglobin species using emitters having optimized center wavelengths |
DE69700384T2 (en) | 1997-12-22 | 1999-11-25 | Hewlett Packard Co | Telemetry system, in particular for medical purposes |
JP3567319B2 (en) | 1997-12-26 | 2004-09-22 | 日本光電工業株式会社 | Probe for pulse oximeter |
US6184521B1 (en) | 1998-01-06 | 2001-02-06 | Masimo Corporation | Photodiode detector with integrated noise shielding |
US6179159B1 (en) | 1998-01-26 | 2001-01-30 | Mariruth D. Gurley | Communicable disease barrier digit cover and dispensing package therefor |
US5978693A (en) | 1998-02-02 | 1999-11-02 | E.P. Limited | Apparatus and method for reduction of motion artifact |
DE69940053D1 (en) | 1998-02-05 | 2009-01-22 | Hema Metrics Inc | METHOD AND DEVICE FOR NON-INVASIVE OBSERVATION OF BLOOD COMPONENTS |
US6014576A (en) | 1998-02-27 | 2000-01-11 | Datex-Ohmeda, Inc. | Segmented photoplethysmographic sensor with universal probe-end |
JPH11244267A (en) | 1998-03-03 | 1999-09-14 | Fuji Photo Film Co Ltd | Blood component concentration measuring device |
US6525386B1 (en) | 1998-03-10 | 2003-02-25 | Masimo Corporation | Non-protruding optoelectronic lens |
US5924980A (en) | 1998-03-11 | 1999-07-20 | Siemens Corporate Research, Inc. | Method and apparatus for adaptively reducing the level of noise in an acquired signal |
US6165005A (en) | 1998-03-19 | 2000-12-26 | Masimo Corporation | Patient cable sensor switch |
US5997343A (en) | 1998-03-19 | 1999-12-07 | Masimo Corporation | Patient cable sensor switch |
US6078833A (en) | 1998-03-25 | 2000-06-20 | I.S.S. (Usa) Inc. | Self referencing photosensor |
US5991648A (en) | 1998-03-30 | 1999-11-23 | Palco Labs, Inc. | Adjustable pulse oximetry sensor for pediatric use |
US6047201A (en) | 1998-04-02 | 2000-04-04 | Jackson, Iii; William H. | Infant blood oxygen monitor and SIDS warning device |
US5916154A (en) | 1998-04-22 | 1999-06-29 | Nellcor Puritan Bennett | Method of enhancing performance in pulse oximetry via electrical stimulation |
US6064899A (en) | 1998-04-23 | 2000-05-16 | Nellcor Puritan Bennett Incorporated | Fiber optic oximeter connector with element indicating wavelength shift |
US6662030B2 (en) | 1998-05-18 | 2003-12-09 | Abbott Laboratories | Non-invasive sensor having controllable temperature feature |
US6094592A (en) | 1998-05-26 | 2000-07-25 | Nellcor Puritan Bennett, Inc. | Methods and apparatus for estimating a physiological parameter using transforms |
US5891021A (en) | 1998-06-03 | 1999-04-06 | Perdue Holdings, Inc. | Partially rigid-partially flexible electro-optical sensor for fingertip transillumination |
EP2319398B1 (en) | 1998-06-03 | 2019-01-16 | Masimo Corporation | Stereo pulse oximeter |
EP0904727B1 (en) | 1998-06-05 | 2000-10-18 | Hewlett-Packard Company | Pulse rate and heart rate coincidence detection for pulse oximetry |
IL124787A0 (en) | 1998-06-07 | 1999-01-26 | Itamar Medical C M 1997 Ltd | Pressure applicator devices particularly useful for non-invasive detection of medical conditions |
US5920263A (en) | 1998-06-11 | 1999-07-06 | Ohmeda, Inc. | De-escalation of alarm priorities in medical devices |
IL124965A (en) | 1998-06-17 | 2002-08-14 | Orsense Ltd | Non-invasive method of optical measurements for determining concentration of a substance in blood |
US5999834A (en) | 1998-06-18 | 1999-12-07 | Ntc Technology, Inc. | Disposable adhesive wrap for use with reusable pulse oximetry sensor and method of making |
US6842635B1 (en) | 1998-08-13 | 2005-01-11 | Edwards Lifesciences Llc | Optical device |
US6285896B1 (en) | 1998-07-13 | 2001-09-04 | Masimo Corporation | Fetal pulse oximetry sensor |
US6671526B1 (en) | 1998-07-17 | 2003-12-30 | Nihon Kohden Corporation | Probe and apparatus for determining concentration of light-absorbing materials in living tissue |
JP2000083933A (en) | 1998-07-17 | 2000-03-28 | Nippon Koden Corp | Instrument for measuring concentration of light absorptive material in vital tissue |
US6949081B1 (en) | 1998-08-26 | 2005-09-27 | Non-Invasive Technology, Inc. | Sensing and interactive drug delivery |
US6430513B1 (en) | 1998-09-04 | 2002-08-06 | Perkinelmer Instruments Llc | Monitoring constituents of an animal organ using statistical correlation |
US20020028990A1 (en) | 1998-09-09 | 2002-03-07 | Shepherd John M. | Device and method for monitoring arterial oxygen saturation |
CA2355337A1 (en) | 1998-09-09 | 2000-03-16 | U.S. Army Institute Of Surgical Research | Method for monitoring arterial oxygen saturation |
US6266547B1 (en) | 1998-09-09 | 2001-07-24 | The United States Of America As Represented By The Secretary Of The Army | Nasopharyngeal airway with reflectance pulse oximeter sensor |
EP1121047A1 (en) | 1998-09-09 | 2001-08-08 | U.S. Army Institute of Surgical Research | Pulse oximeter sensor combined with oropharyngeal airway and bite block |
AU754659B2 (en) | 1998-09-09 | 2002-11-21 | Government Of The United States Of America As Represented By The Secretary Of The Army | Disposable pulse oximeter assembly and protective cover therefor |
US6393310B1 (en) | 1998-09-09 | 2002-05-21 | J. Todd Kuenstner | Methods and systems for clinical analyte determination by visible and infrared spectroscopy |
US6144867A (en) | 1998-09-18 | 2000-11-07 | The United States Of America As Represented By The Secretary Of The Army | Self-piercing pulse oximeter sensor assembly |
US6064898A (en) | 1998-09-21 | 2000-05-16 | Essential Medical Devices | Non-invasive blood component analyzer |
AU758458B2 (en) | 1998-09-29 | 2003-03-20 | Mallinckrodt, Inc. | Oximeter sensor with encoded temperature characteristic |
US6298252B1 (en) | 1998-09-29 | 2001-10-02 | Mallinckrodt, Inc. | Oximeter sensor with encoder connected to detector |
WO2000018291A1 (en) | 1998-09-29 | 2000-04-06 | Mallinckrodt Inc. | Multiple-code oximeter calibration element |
JP2002527134A (en) | 1998-10-13 | 2002-08-27 | ソマネティクス コーポレイション | Multi-channel non-invasive tissue oximeter |
US6321100B1 (en) | 1999-07-13 | 2001-11-20 | Sensidyne, Inc. | Reusable pulse oximeter probe with disposable liner |
US6519486B1 (en) | 1998-10-15 | 2003-02-11 | Ntc Technology Inc. | Method, apparatus and system for removing motion artifacts from measurements of bodily parameters |
US6721585B1 (en) | 1998-10-15 | 2004-04-13 | Sensidyne, Inc. | Universal modular pulse oximeter probe for use with reusable and disposable patient attachment devices |
US6684091B2 (en) | 1998-10-15 | 2004-01-27 | Sensidyne, Inc. | Reusable pulse oximeter probe and disposable bandage method |
US6343224B1 (en) | 1998-10-15 | 2002-01-29 | Sensidyne, Inc. | Reusable pulse oximeter probe and disposable bandage apparatus |
US6519487B1 (en) | 1998-10-15 | 2003-02-11 | Sensidyne, Inc. | Reusable pulse oximeter probe and disposable bandage apparatus |
US6144868A (en) | 1998-10-15 | 2000-11-07 | Sensidyne, Inc. | Reusable pulse oximeter probe and disposable bandage apparatus |
US6006120A (en) | 1998-10-22 | 1999-12-21 | Palco Labs, Inc. | Cordless Pulse oximeter |
US6261236B1 (en) | 1998-10-26 | 2001-07-17 | Valentin Grimblatov | Bioresonance feedback method and apparatus |
US6061584A (en) | 1998-10-28 | 2000-05-09 | Lovejoy; David A. | Pulse oximetry sensor |
US6144444A (en) | 1998-11-06 | 2000-11-07 | Medtronic Avecor Cardiovascular, Inc. | Apparatus and method to determine blood parameters |
US7006855B1 (en) | 1998-11-16 | 2006-02-28 | S.P.O. Medical Equipment Ltd. | Sensor for radiance based diagnostics |
US6463311B1 (en) | 1998-12-30 | 2002-10-08 | Masimo Corporation | Plethysmograph pulse recognition processor |
US6684090B2 (en) | 1999-01-07 | 2004-01-27 | Masimo Corporation | Pulse oximetry data confidence indicator |
US6606511B1 (en) | 1999-01-07 | 2003-08-12 | Masimo Corporation | Pulse oximetry pulse indicator |
US6280381B1 (en) | 1999-07-22 | 2001-08-28 | Instrumentation Metrics, Inc. | Intelligent system for noninvasive blood analyte prediction |
EP1148809B1 (en) | 1999-01-25 | 2007-11-14 | Masimo Corporation | Universal/upgrading pulse oximeter |
US20020140675A1 (en) | 1999-01-25 | 2002-10-03 | Ali Ammar Al | System and method for altering a display mode based on a gravity-responsive sensor |
US6658276B2 (en) | 1999-01-25 | 2003-12-02 | Masimo Corporation | Pulse oximeter user interface |
US6770028B1 (en) * | 1999-01-25 | 2004-08-03 | Masimo Corporation | Dual-mode pulse oximeter |
US6438399B1 (en) | 1999-02-16 | 2002-08-20 | The Children's Hospital Of Philadelphia | Multi-wavelength frequency domain near-infrared cerebral oximeter |
DE60041577D1 (en) | 1999-03-08 | 2009-04-02 | Nellcor Puritan Bennett Llc | PROCESS AND CIRCUIT FOR STORAGE AND READY |
IL129790A0 (en) | 1999-03-09 | 2000-02-29 | Orsense Ltd | A device for enhancement of blood-related signals |
US6360114B1 (en) | 1999-03-25 | 2002-03-19 | Masimo Corporation | Pulse oximeter probe-off detector |
US6675031B1 (en) | 1999-04-14 | 2004-01-06 | Mallinckrodt Inc. | Method and circuit for indicating quality and accuracy of physiological measurements |
US6308089B1 (en) | 1999-04-14 | 2001-10-23 | O.B. Scientific, Inc. | Limited use medical probe |
JP2003528645A (en) | 1999-04-23 | 2003-09-30 | マサチューセッツ インスティテュート オブ テクノロジー | Isolation ring sensor design |
US6226539B1 (en) | 1999-05-26 | 2001-05-01 | Mallinckrodt, Inc. | Pulse oximeter having a low power led drive |
EP1196862A1 (en) | 1999-06-10 | 2002-04-17 | Koninklijke Philips Electronics N.V. | Quality indicator for measurement signals, in particular, for medical measurement signals such as those used in measuring oxygen saturation |
US6654623B1 (en) | 1999-06-10 | 2003-11-25 | Koninklijke Philips Electronics N.V. | Interference suppression for measuring signals with periodic wanted signals |
WO2000077674A1 (en) | 1999-06-10 | 2000-12-21 | Koninklijke Philips Electronics N.V. | Recognition of a useful signal in a measurement signal |
US6587704B1 (en) | 1999-06-16 | 2003-07-01 | Orsense Ltd. | Method for non-invasive optical measurements of blood parameters |
US6526300B1 (en) | 1999-06-18 | 2003-02-25 | Masimo Corporation | Pulse oximeter probe-off detection system |
US20030018243A1 (en) | 1999-07-07 | 2003-01-23 | Gerhardt Thomas J. | Selectively plated sensor |
JP2001017404A (en) | 1999-07-09 | 2001-01-23 | Koike Medical:Kk | Medical measuring device |
US6760609B2 (en) | 1999-07-14 | 2004-07-06 | Providence Health System - Oregon | Adaptive calibration pulsed oximetry method and device |
CA2375635A1 (en) | 1999-07-14 | 2001-01-18 | Providence Health System-Oregon | Adaptive calibration pulsed oximetry method and device |
US6512937B2 (en) | 1999-07-22 | 2003-01-28 | Sensys Medical, Inc. | Multi-tier method of developing localized calibration models for non-invasive blood analyte prediction |
US6675029B2 (en) | 1999-07-22 | 2004-01-06 | Sensys Medical, Inc. | Apparatus and method for quantification of tissue hydration using diffuse reflectance spectroscopy |
AU6894500A (en) | 1999-08-06 | 2001-03-05 | Board Of Regents, The University Of Texas System | Optoacoustic monitoring of blood oxygenation |
US7904139B2 (en) | 1999-08-26 | 2011-03-08 | Non-Invasive Technology Inc. | Optical examination of biological tissue using non-contact irradiation and detection |
US6515273B2 (en) | 1999-08-26 | 2003-02-04 | Masimo Corporation | System for indicating the expiration of the useful operating life of a pulse oximetry sensor |
AU7355900A (en) | 1999-09-10 | 2001-04-10 | Stephen H. Gorski | Oximeter sensor with functional liner |
JP3627214B2 (en) | 1999-09-13 | 2005-03-09 | 日本光電工業株式会社 | Blood absorption substance measuring device |
US6708049B1 (en) | 1999-09-28 | 2004-03-16 | Nellcor Puritan Bennett Incorporated | Sensor with signature of data relating to sensor |
US6213952B1 (en) | 1999-09-28 | 2001-04-10 | Orsense Ltd. | Optical device for non-invasive measurement of blood related signals utilizing a finger holder |
US6339715B1 (en) | 1999-09-30 | 2002-01-15 | Ob Scientific | Method and apparatus for processing a physiological signal |
NZ518142A (en) | 1999-10-07 | 2003-11-28 | Alexander K | Optical determination of blood characteristics accounting for heart/limb relative height |
US6400971B1 (en) | 1999-10-12 | 2002-06-04 | Orsense Ltd. | Optical device for non-invasive measurement of blood-related signals and a finger holder therefor |
US7359741B2 (en) | 1999-11-15 | 2008-04-15 | Spo Medical Equipment Ltd. | Sensor and radiance based diagnostics |
CA2290083A1 (en) | 1999-11-19 | 2001-05-19 | Linde Medical Sensors Ag. | Device for the combined measurement of the arterial oxygen saturation and the transcutaneous co2 partial pressure of an ear lobe |
US6665551B1 (en) | 1999-11-19 | 2003-12-16 | Nihon Kohden Corporation | Current driving system of light emitting diode |
WO2001037725A1 (en) | 1999-11-22 | 2001-05-31 | Mallinckrodt Inc. | Pulse oximeter sensor with widened metal strip |
JP2001149349A (en) | 1999-11-26 | 2001-06-05 | Nippon Koden Corp | Sensor for living body |
US6622095B2 (en) | 1999-11-30 | 2003-09-16 | Nihon Kohden Corporation | Apparatus for determining concentrations of hemoglobins |
US6415236B2 (en) | 1999-11-30 | 2002-07-02 | Nihon Kohden Corporation | Apparatus for determining concentrations of hemoglobins |
US6542764B1 (en) | 1999-12-01 | 2003-04-01 | Masimo Corporation | Pulse oximeter monitor for expressing the urgency of the patient's condition |
US6671531B2 (en) | 1999-12-09 | 2003-12-30 | Masimo Corporation | Sensor wrap including foldable applicator |
US6377829B1 (en) | 1999-12-09 | 2002-04-23 | Masimo Corporation | Resposable pulse oximetry sensor |
US6950687B2 (en) | 1999-12-09 | 2005-09-27 | Masimo Corporation | Isolation and communication element for a resposable pulse oximetry sensor |
US6397092B1 (en) | 1999-12-17 | 2002-05-28 | Datex-Ohmeda, Inc. | Oversampling pulse oximeter |
US6408198B1 (en) | 1999-12-17 | 2002-06-18 | Datex-Ohmeda, Inc. | Method and system for improving photoplethysmographic analyte measurements by de-weighting motion-contaminated data |
US6360113B1 (en) | 1999-12-17 | 2002-03-19 | Datex-Ohmeda, Inc. | Photoplethysmographic instrument |
US6363269B1 (en) | 1999-12-17 | 2002-03-26 | Datex-Ohmeda, Inc. | Synchronized modulation/demodulation method and apparatus for frequency division multiplexed spectrophotometric system |
US6381479B1 (en) | 1999-12-17 | 2002-04-30 | Date-Ohmeda, Inc. | Pulse oximeter with improved DC and low frequency rejection |
US6152754A (en) | 1999-12-21 | 2000-11-28 | Masimo Corporation | Circuit board based cable connector |
US6711424B1 (en) | 1999-12-22 | 2004-03-23 | Orsense Ltd. | Method of optical measurement for determing various parameters of the patient's blood |
US6419671B1 (en) | 1999-12-23 | 2002-07-16 | Visx, Incorporated | Optical feedback system for vision correction |
US6594513B1 (en) | 2000-01-12 | 2003-07-15 | Paul D. Jobsis | Method and apparatus for determining oxygen saturation of blood in body organs |
US7198778B2 (en) | 2000-01-18 | 2007-04-03 | Mallinckrodt Inc. | Tumor-targeted optical contrast agents |
US6564088B1 (en) | 2000-01-21 | 2003-05-13 | University Of Massachusetts | Probe for localized tissue spectroscopy |
EP1251770A4 (en) | 2000-01-28 | 2005-05-25 | Gen Hospital Corp | Fetal pulse oximetry |
DE60133533T2 (en) | 2000-02-10 | 2009-06-25 | Draeger Medical Systems, Inc., Danvers | METHOD AND DEVICE FOR DETECTING A PHYSIOLOGICAL PARAMETER |
AU3687401A (en) | 2000-02-11 | 2001-08-20 | U S Army Inst Of Surgical Res | Pacifier pulse oximeter sensor |
US6385821B1 (en) | 2000-02-17 | 2002-05-14 | Udt Sensors, Inc. | Apparatus for securing an oximeter probe to a patient |
IL135077A0 (en) | 2000-03-15 | 2001-05-20 | Orsense Ltd | A probe for use in non-invasive measurements of blood related parameters |
US6594511B2 (en) | 2000-03-29 | 2003-07-15 | Robert T. Stone | Method and apparatus for determining physiological characteristics |
US6453183B1 (en) | 2000-04-10 | 2002-09-17 | Stephen D. Walker | Cerebral oxygenation monitor |
ES2392818T3 (en) | 2000-04-17 | 2012-12-14 | Nellcor Puritan Bennett Llc | Pulse oximeter sensor with section function |
US6699199B2 (en) | 2000-04-18 | 2004-03-02 | Massachusetts Institute Of Technology | Photoplethysmograph signal-to-noise line enhancement |
WO2001082790A2 (en) | 2000-04-28 | 2001-11-08 | Kinderlife Instruments, Inc. | Method for determining blood constituents |
US6456862B2 (en) | 2000-05-02 | 2002-09-24 | Cas Medical Systems, Inc. | Method for non-invasive spectrophotometric blood oxygenation monitoring |
US6449501B1 (en) | 2000-05-26 | 2002-09-10 | Ob Scientific, Inc. | Pulse oximeter with signal sonification |
US6510331B1 (en) | 2000-06-05 | 2003-01-21 | Glenn Williams | Switching device for multi-sensor array |
US6430525B1 (en) | 2000-06-05 | 2002-08-06 | Masimo Corporation | Variable mode averager |
GB0014854D0 (en) | 2000-06-16 | 2000-08-09 | Isis Innovation | System and method for acquiring data |
GB0014855D0 (en) | 2000-06-16 | 2000-08-09 | Isis Innovation | Combining measurements from different sensors |
US6470199B1 (en) | 2000-06-21 | 2002-10-22 | Masimo Corporation | Elastic sock for positioning an optical probe |
DE10030862B4 (en) | 2000-06-23 | 2006-02-09 | Nicolay Verwaltungs-Gmbh | Device for fixing a medical measuring device, in particular a pulse oximetry sensor, and use of such a device |
US6697656B1 (en) | 2000-06-27 | 2004-02-24 | Masimo Corporation | Pulse oximetry sensor compatible with multiple pulse oximetry systems |
US6587703B2 (en) | 2000-09-18 | 2003-07-01 | Photonify Technologies, Inc. | System and method for measuring absolute oxygen saturation |
US6597931B1 (en) | 2000-09-18 | 2003-07-22 | Photonify Technologies, Inc. | System and method for absolute oxygen saturation |
US6889153B2 (en) | 2001-08-09 | 2005-05-03 | Thomas Dietiker | System and method for a self-calibrating non-invasive sensor |
US6719686B2 (en) | 2000-08-30 | 2004-04-13 | Mallinckrodt, Inc. | Fetal probe having an optical imaging device |
US6591123B2 (en) | 2000-08-31 | 2003-07-08 | Mallinckrodt Inc. | Oximeter sensor with digital memory recording sensor data |
US6606510B2 (en) | 2000-08-31 | 2003-08-12 | Mallinckrodt Inc. | Oximeter sensor with digital memory encoding patient data |
US6553241B2 (en) | 2000-08-31 | 2003-04-22 | Mallinckrodt Inc. | Oximeter sensor with digital memory encoding sensor expiration data |
US6628975B1 (en) | 2000-08-31 | 2003-09-30 | Mallinckrodt Inc. | Oximeter sensor with digital memory storing data |
US6600940B1 (en) | 2000-08-31 | 2003-07-29 | Mallinckrodt Inc. | Oximeter sensor with digital memory |
US6571113B1 (en) | 2000-09-21 | 2003-05-27 | Mallinckrodt, Inc. | Oximeter sensor adapter with coding element |
US6490466B1 (en) | 2000-09-21 | 2002-12-03 | Mallinckrodt Inc. | Interconnect circuit between non-compatible oximeter and sensor |
JP3845776B2 (en) | 2000-09-22 | 2006-11-15 | 日本光電工業株式会社 | Absorbent concentration measuring device in blood |
IL138683A0 (en) | 2000-09-25 | 2001-10-31 | Vital Medical Ltd | Apparatus and method for monitoring tissue vitality parameters |
US6434408B1 (en) | 2000-09-29 | 2002-08-13 | Datex-Ohmeda, Inc. | Pulse oximetry method and system with improved motion correction |
US6505060B1 (en) | 2000-09-29 | 2003-01-07 | Datex-Ohmeda, Inc. | Method and apparatus for determining pulse oximetry differential values |
IL138884A (en) | 2000-10-05 | 2006-07-05 | Conmed Corp | Pulse oximeter and a method of its operation |
US6819950B2 (en) | 2000-10-06 | 2004-11-16 | Alexander K. Mills | Method for noninvasive continuous determination of physiologic characteristics |
US6738671B2 (en) * | 2000-10-26 | 2004-05-18 | Medtronic, Inc. | Externally worn transceiver for use with an implantable medical device |
US6519484B1 (en) | 2000-11-01 | 2003-02-11 | Ge Medical Systems Information Technologies, Inc. | Pulse oximetry sensor |
US6466809B1 (en) | 2000-11-02 | 2002-10-15 | Datex-Ohmeda, Inc. | Oximeter sensor having laminated housing with flat patient interface surface |
US6560470B1 (en) | 2000-11-15 | 2003-05-06 | Datex-Ohmeda, Inc. | Electrical lockout photoplethysmographic measurement system |
US6505133B1 (en) | 2000-11-15 | 2003-01-07 | Datex-Ohmeda, Inc. | Simultaneous signal attenuation measurements utilizing code division multiplexing |
US6594512B2 (en) | 2000-11-21 | 2003-07-15 | Siemens Medical Solutions Usa, Inc. | Method and apparatus for estimating a physiological parameter from a physiological signal |
US6760610B2 (en) | 2000-11-23 | 2004-07-06 | Sentec Ag | Sensor and method for measurement of physiological parameters |
US20020068859A1 (en) | 2000-12-01 | 2002-06-06 | Knopp Christina A. | Laser diode drive scheme for noise reduction in photoplethysmographic measurements |
US6760607B2 (en) | 2000-12-29 | 2004-07-06 | Masimo Corporation | Ribbon cable substrate pulse oximetry sensor |
WO2002056760A1 (en) | 2001-01-19 | 2002-07-25 | Tufts University | Method for measuring venous oxygen saturation |
US6501974B2 (en) | 2001-01-22 | 2002-12-31 | Datex-Ohmeda, Inc. | Compensation of human variability in pulse oximetry |
US6510329B2 (en) | 2001-01-24 | 2003-01-21 | Datex-Ohmeda, Inc. | Detection of sensor off conditions in a pulse oximeter |
US6618602B2 (en) | 2001-03-08 | 2003-09-09 | Palco Labs, Inc. | Method and apparatus for simultaneously determining a patient's identification and blood oxygen saturation |
US20020133067A1 (en) | 2001-03-15 | 2002-09-19 | Jackson William H. | New born and premature infant SIDS warning device |
US7239902B2 (en) | 2001-03-16 | 2007-07-03 | Nellor Puritan Bennett Incorporated | Device and method for monitoring body fluid and electrolyte disorders |
US6591122B2 (en) | 2001-03-16 | 2003-07-08 | Nellcor Puritan Bennett Incorporated | Device and method for monitoring body fluid and electrolyte disorders |
US6556852B1 (en) | 2001-03-27 | 2003-04-29 | I-Medik, Inc. | Earpiece with sensors to measure/monitor multiple physiological variables |
JP2002303576A (en) | 2001-04-05 | 2002-10-18 | Nippon Colin Co Ltd | Oxygen saturation measuring device |
KR100612827B1 (en) | 2001-04-19 | 2006-08-14 | 삼성전자주식회사 | Method and apparatus for noninvasively measuring hemoglobin concentration and oxygen saturation |
US20050043599A1 (en) | 2001-04-19 | 2005-02-24 | O'mara Sean T. | Pulse oximetry device and method |
US6505061B2 (en) | 2001-04-20 | 2003-01-07 | Datex-Ohmeda, Inc. | Pulse oximetry sensor with improved appendage cushion |
US20020156354A1 (en) | 2001-04-20 | 2002-10-24 | Larson Eric Russell | Pulse oximetry sensor with improved spring |
EP1254628B1 (en) | 2001-05-03 | 2006-12-20 | Instrumentarium Corporation | Pulse oximeter |
US6985764B2 (en) | 2001-05-03 | 2006-01-10 | Masimo Corporation | Flex circuit shielded optical sensor |
US6801798B2 (en) | 2001-06-20 | 2004-10-05 | Purdue Research Foundation | Body-member-illuminating pressure cuff for use in optical noninvasive measurement of blood parameters |
SG126677A1 (en) | 2001-06-26 | 2006-11-29 | Meng Ting Choon | Method and device for measuring blood sugar level |
US6801802B2 (en) | 2001-06-29 | 2004-10-05 | Ge Medical Systems Information Technologies, Inc. | System and method for selecting physiological data from a plurality of physiological data sources |
US6850787B2 (en) | 2001-06-29 | 2005-02-01 | Masimo Laboratories, Inc. | Signal component processor |
US6697658B2 (en) | 2001-07-02 | 2004-02-24 | Masimo Corporation | Low power pulse oximeter |
US6731967B1 (en) | 2001-07-16 | 2004-05-04 | Pacesetter, Inc. | Methods and devices for vascular plethysmography via modulation of source intensity |
US6754516B2 (en) | 2001-07-19 | 2004-06-22 | Nellcor Puritan Bennett Incorporated | Nuisance alarm reductions in a physiological monitor |
US6802812B1 (en) | 2001-07-27 | 2004-10-12 | Nostix Llc | Noninvasive optical sensor for measuring near infrared light absorbing analytes |
US6654621B2 (en) | 2001-08-29 | 2003-11-25 | Bci, Inc. | Finger oximeter with finger grip suspension system |
US6668183B2 (en) | 2001-09-11 | 2003-12-23 | Datex-Ohmeda, Inc. | Diode detection circuit |
IL145445A (en) | 2001-09-13 | 2006-12-31 | Conmed Corp | Signal processing method and device for signal-to-noise improvement |
US6671532B1 (en) | 2001-09-17 | 2003-12-30 | Respironics Novametrix, Inc. | Pulse oximetry sensor and dispensing method |
GB0123395D0 (en) | 2001-09-28 | 2001-11-21 | Isis Innovation | Locating features ina photoplethysmograph signal |
US6697655B2 (en) | 2001-10-05 | 2004-02-24 | Mortara Instrument, Inc. | Low power pulse oximeter |
US6564077B2 (en) | 2001-10-10 | 2003-05-13 | Mortara Instrument, Inc. | Method and apparatus for pulse oximetry |
US6697653B2 (en) | 2001-10-10 | 2004-02-24 | Datex-Ohmeda, Inc. | Reduced wire count voltage drop sense |
US20030073890A1 (en) | 2001-10-10 | 2003-04-17 | Hanna D. Alan | Plethysmographic signal processing method and system |
US6840904B2 (en) | 2001-10-11 | 2005-01-11 | Jason Goldberg | Medical monitoring device and system |
US6773397B2 (en) | 2001-10-11 | 2004-08-10 | Draeger Medical Systems, Inc. | System for processing signal data representing physiological parameters |
US20030073889A1 (en) | 2001-10-11 | 2003-04-17 | Keilbach Kevin A. | Monitoring led wavelength shift in photoplethysmography |
US6748254B2 (en) | 2001-10-12 | 2004-06-08 | Nellcor Puritan Bennett Incorporated | Stacked adhesive optical sensor |
WO2003034911A2 (en) | 2001-10-22 | 2003-05-01 | Vsm Medtech Ltd. | Physiological parameter monitoring system and sensor assembly for same |
US6839579B1 (en) | 2001-11-02 | 2005-01-04 | Nellcor Puritan Bennett Incorporated | Temperature indicating oximetry sensor |
US6701170B2 (en) | 2001-11-02 | 2004-03-02 | Nellcor Puritan Bennett Incorporated | Blind source separation of pulse oximetry signals |
JP3709836B2 (en) | 2001-11-20 | 2005-10-26 | コニカミノルタセンシング株式会社 | Blood component measuring device |
US20030100840A1 (en) | 2001-11-28 | 2003-05-29 | Nihon Kohden Corporation | Pulse photometry probe |
US6839580B2 (en) | 2001-12-06 | 2005-01-04 | Ric Investments, Inc. | Adaptive calibration for pulse oximetry |
US6780158B2 (en) | 2001-12-14 | 2004-08-24 | Nihon Kohden Corporation | Signal processing method and pulse wave signal processing method |
US6934570B2 (en) | 2002-01-08 | 2005-08-23 | Masimo Corporation | Physiological sensor combination |
US6668182B2 (en) | 2002-01-10 | 2003-12-23 | Northeast Monitoring | Pulse oxymetry data processing |
US6822564B2 (en) | 2002-01-24 | 2004-11-23 | Masimo Corporation | Parallel measurement alarm processor |
US7020507B2 (en) | 2002-01-31 | 2006-03-28 | Dolphin Medical, Inc. | Separating motion from cardiac signals using second order derivative of the photo-plethysmogram and fast fourier transforms |
DE60315596T2 (en) | 2002-01-31 | 2008-05-15 | Loughborough University Enterprises Ltd., Loughborough | VENOUS PULSE OXIMETRY |
CA2475726C (en) | 2002-02-14 | 2010-02-09 | Toshinori Kato | Apparatus for evaluating biological function |
US6882874B2 (en) | 2002-02-15 | 2005-04-19 | Datex-Ohmeda, Inc. | Compensation of human variability in pulse oximetry |
US6709402B2 (en) | 2002-02-22 | 2004-03-23 | Datex-Ohmeda, Inc. | Apparatus and method for monitoring respiration with a pulse oximeter |
US6702752B2 (en) | 2002-02-22 | 2004-03-09 | Datex-Ohmeda, Inc. | Monitoring respiration based on plethysmographic heart rate signal |
US20040039273A1 (en) | 2002-02-22 | 2004-02-26 | Terry Alvin Mark | Cepstral domain pulse oximetry |
US6805673B2 (en) | 2002-02-22 | 2004-10-19 | Datex-Ohmeda, Inc. | Monitoring mayer wave effects based on a photoplethysmographic signal |
EP1485015A1 (en) | 2002-02-22 | 2004-12-15 | Datex-Ohmeda, Inc. | Cepstral domain pulse oximetry |
WO2003071939A1 (en) | 2002-02-22 | 2003-09-04 | Masimo Corporation | Active pulse spectraphotometry |
US20050177034A1 (en) | 2002-03-01 | 2005-08-11 | Terry Beaumont | Ear canal sensing device |
US20030171662A1 (en) | 2002-03-07 | 2003-09-11 | O'connor Michael William | Non-adhesive flexible electro-optical sensor for fingertip trans-illumination |
US6863652B2 (en) | 2002-03-13 | 2005-03-08 | Draeger Medical Systems, Inc. | Power conserving adaptive control system for generating signal in portable medical devices |
KR100455289B1 (en) | 2002-03-16 | 2004-11-08 | 삼성전자주식회사 | Method of diagnosing using a ray and apparatus thereof |
WO2003080152A2 (en) | 2002-03-21 | 2003-10-02 | Datex-Ohmeda, Inc. | Neonatal bootie wrap |
US6647279B2 (en) | 2002-03-22 | 2003-11-11 | Jonas Alexander Pologe | Hybrid optical delivery system for photoplethysmography |
US6850788B2 (en) | 2002-03-25 | 2005-02-01 | Masimo Corporation | Physiological measurement communications adapter |
DE10213692B4 (en) | 2002-03-27 | 2013-05-23 | Weinmann Diagnostics Gmbh & Co. Kg | Method for controlling a device and device for measuring ingredients in the blood |
US7892183B2 (en) | 2002-04-19 | 2011-02-22 | Pelikan Technologies, Inc. | Method and apparatus for body fluid sampling and analyte sensing |
US6690958B1 (en) | 2002-05-07 | 2004-02-10 | Nostix Llc | Ultrasound-guided near infrared spectrophotometer |
US20030212316A1 (en) | 2002-05-10 | 2003-11-13 | Leiden Jeffrey M. | Method and apparatus for determining blood parameters and vital signs of a patient |
US6711425B1 (en) | 2002-05-28 | 2004-03-23 | Ob Scientific, Inc. | Pulse oximeter with calibration stabilization |
US7024235B2 (en) | 2002-06-20 | 2006-04-04 | University Of Florida Research Foundation, Inc. | Specially configured nasal pulse oximeter/photoplethysmography probes, and combined nasal probe/cannula, selectively with sampler for capnography, and covering sleeves for same |
US6909912B2 (en) | 2002-06-20 | 2005-06-21 | University Of Florida | Non-invasive perfusion monitor and system, specially configured oximeter probes, methods of using same, and covers for probes |
US6865407B2 (en) | 2002-07-11 | 2005-03-08 | Optical Sensors, Inc. | Calibration technique for non-invasive medical devices |
JP4395068B2 (en) | 2002-07-15 | 2010-01-06 | イタマール メディカル リミテッド | Body surface probe, apparatus, and method for non-invasive detection of medical conditions |
AU2003254135B2 (en) | 2002-07-26 | 2006-11-16 | Cas Medical Systems, Inc. | Method for spectrophotometric blood oxygenation monitoring |
US6850789B2 (en) | 2002-07-29 | 2005-02-01 | Welch Allyn, Inc. | Combination SPO2/temperature measuring apparatus |
US7096054B2 (en) | 2002-08-01 | 2006-08-22 | Masimo Corporation | Low noise optical housing |
KR100493157B1 (en) | 2002-08-02 | 2005-06-03 | 삼성전자주식회사 | Probe using in measuring organism signal and system for measuring organism signal comprising the same |
US7133711B2 (en) | 2002-08-07 | 2006-11-07 | Orsense, Ltd. | Method and system for decomposition of multiple channel signals |
US6720734B2 (en) | 2002-08-08 | 2004-04-13 | Datex-Ohmeda, Inc. | Oximeter with nulled op-amp current feedback |
US6707257B2 (en) | 2002-08-08 | 2004-03-16 | Datex-Ohmeda, Inc. | Ferrite stabilized LED drive |
US6825619B2 (en) | 2002-08-08 | 2004-11-30 | Datex-Ohmeda, Inc. | Feedback-controlled LED switching |
US6763256B2 (en) | 2002-08-16 | 2004-07-13 | Optical Sensors, Inc. | Pulse oximeter |
US6879850B2 (en) | 2002-08-16 | 2005-04-12 | Optical Sensors Incorporated | Pulse oximeter with motion detection |
US6745061B1 (en) | 2002-08-21 | 2004-06-01 | Datex-Ohmeda, Inc. | Disposable oximetry sensor |
US6643531B1 (en) | 2002-08-22 | 2003-11-04 | Bci, Inc. | Combination fingerprint and oximetry device |
US6912413B2 (en) | 2002-09-13 | 2005-06-28 | Ge Healthcare Finland Oy | Pulse oximeter |
US7341559B2 (en) | 2002-09-14 | 2008-03-11 | Masimo Corporation | Pulse oximetry ear sensor |
US20040186358A1 (en) | 2002-09-25 | 2004-09-23 | Bart Chernow | Monitoring system containing a hospital bed with integrated display |
US7142901B2 (en) | 2002-09-25 | 2006-11-28 | Masimo Corporation | Parameter compensated physiological monitor |
US7810359B2 (en) | 2002-10-01 | 2010-10-12 | Nellcor Puritan Bennett Llc | Headband with tension indicator |
US7096052B2 (en) | 2002-10-04 | 2006-08-22 | Masimo Corporation | Optical probe including predetermined emission wavelength based on patient type |
JP4352315B2 (en) | 2002-10-31 | 2009-10-28 | 日本光電工業株式会社 | Signal processing method / apparatus and pulse photometer using the same |
WO2004047631A2 (en) | 2002-11-22 | 2004-06-10 | Masimo Laboratories, Inc. | Blood parameter measurement system |
JP4489385B2 (en) | 2002-12-12 | 2010-06-23 | 株式会社日立メディコ | Measuring probe and biological light measuring device |
AU2003297060A1 (en) | 2002-12-13 | 2004-07-09 | Massachusetts Institute Of Technology | Vibratory venous and arterial oximetry sensor |
US6754515B1 (en) | 2002-12-17 | 2004-06-22 | Kestrel Labs, Inc. | Stabilization of noisy optical sources in photoplethysmography |
KR100499139B1 (en) | 2003-01-07 | 2005-07-04 | 삼성전자주식회사 | Method of removing abnormal data and blood constituent analysing system using spectroscopy employing the same |
US7006856B2 (en) | 2003-01-10 | 2006-02-28 | Nellcor Puritan Bennett Incorporated | Signal quality metrics design for qualifying data for a physiological monitor |
US7016715B2 (en) | 2003-01-13 | 2006-03-21 | Nellcorpuritan Bennett Incorporated | Selection of preset filter parameters based on signal quality |
US7225006B2 (en) | 2003-01-23 | 2007-05-29 | Masimo Corporation | Attachment and optical probe |
US6920345B2 (en) | 2003-01-24 | 2005-07-19 | Masimo Corporation | Optical sensor including disposable and reusable elements |
JP4284674B2 (en) | 2003-01-31 | 2009-06-24 | 日本光電工業株式会社 | Absorbent concentration measuring device in blood |
WO2004069046A1 (en) | 2003-02-05 | 2004-08-19 | Philips Intellectual Property & Standards Gmbh | Finger medical sensor |
JP4526532B2 (en) | 2003-02-27 | 2010-08-18 | ネルコア ピューリタン ベネット アイルランド | Signal analysis and processing methods |
US6982928B2 (en) | 2003-04-21 | 2006-01-03 | Saudi Arabian Oil Company | Seismic P-wave velocity derived from vibrator control system |
KR100571811B1 (en) | 2003-05-09 | 2006-04-17 | 삼성전자주식회사 | Ear type measurement apparatus for bio signal |
US6993372B2 (en) | 2003-06-03 | 2006-01-31 | Orsense Ltd. | Method and system for use in non-invasive optical measurements of blood parameters |
US6992772B2 (en) | 2003-06-19 | 2006-01-31 | Optix Lp | Method and apparatus for optical sampling to reduce interfering variances |
US7047056B2 (en) | 2003-06-25 | 2006-05-16 | Nellcor Puritan Bennett Incorporated | Hat-based oximeter sensor |
US7025728B2 (en) | 2003-06-30 | 2006-04-11 | Nihon Kohden Corporation | Method for reducing noise, and pulse photometer using the method |
US7003338B2 (en) | 2003-07-08 | 2006-02-21 | Masimo Corporation | Method and apparatus for reducing coupling between signals |
JP4326866B2 (en) | 2003-07-17 | 2009-09-09 | 帝人株式会社 | How to predict the occurrence of acute exacerbations |
WO2005020120A2 (en) | 2003-08-20 | 2005-03-03 | Koninklijke Philips Electronics N.V. | A system and method for detecting signal artifacts |
US7107088B2 (en) | 2003-08-25 | 2006-09-12 | Sarnoff Corporation | Pulse oximetry methods and apparatus for use within an auditory canal |
WO2005020798A2 (en) | 2003-08-27 | 2005-03-10 | Datex-Ohmeda, Inc. | Multi-domain motion estimation and plethysmographic recognition using fuzzy neural-nets |
US20050075550A1 (en) | 2003-10-03 | 2005-04-07 | Lindekugel Eric W. | Quick-clip sensor holder |
US7254434B2 (en) | 2003-10-14 | 2007-08-07 | Masimo Corporation | Variable pressure reusable sensor |
US7305262B2 (en) | 2003-12-11 | 2007-12-04 | Ge Medical Systems Information Technologies, Inc. | Apparatus and method for acquiring oximetry and electrocardiogram signals |
US7280858B2 (en) | 2004-01-05 | 2007-10-09 | Masimo Corporation | Pulse oximetry sensor |
US20050267346A1 (en) | 2004-01-30 | 2005-12-01 | 3Wave Optics, Llc | Non-invasive blood component measurement system |
CA2555807A1 (en) | 2004-02-12 | 2005-08-25 | Biopeak Corporation | Non-invasive method and apparatus for determining a physiological parameter |
US7162288B2 (en) | 2004-02-25 | 2007-01-09 | Nellcor Purtain Bennett Incorporated | Techniques for detecting heart pulses and reducing power consumption in sensors |
US20050197548A1 (en) | 2004-03-05 | 2005-09-08 | Elekon Industries Usa, Inc. | Disposable/reusable flexible sensor |
US7277741B2 (en) | 2004-03-09 | 2007-10-02 | Nellcor Puritan Bennett Incorporated | Pulse oximetry motion artifact rejection using near infrared absorption by water |
US20050228248A1 (en) | 2004-04-07 | 2005-10-13 | Thomas Dietiker | Clip-type sensor having integrated biasing and cushioning means |
WO2006012205A2 (en) * | 2004-06-24 | 2006-02-02 | Convergent Engineering, Inc. | METHOD AND APPARATUS FOR NON-INVASIVE PREDICTION OF INTRINSIC POSITIVE END-EXPIRATORY PRESSURE (PEEPi) IN PATIENTS RECEIVING VENTILATOR SUPPORT |
US7551950B2 (en) | 2004-06-29 | 2009-06-23 | O2 Medtech, Inc,. | Optical apparatus and method of use for non-invasive tomographic scan of biological tissues |
US7343186B2 (en) | 2004-07-07 | 2008-03-11 | Masimo Laboratories, Inc. | Multi-wavelength physiological monitor |
US7359742B2 (en) | 2004-11-12 | 2008-04-15 | Nonin Medical, Inc. | Sensor assembly |
US7548771B2 (en) | 2005-03-31 | 2009-06-16 | Nellcor Puritan Bennett Llc | Pulse oximetry sensor and technique for using the same on a distal region of a patient's digit |
US7590439B2 (en) | 2005-08-08 | 2009-09-15 | Nellcor Puritan Bennett Llc | Bi-stable medical sensor and technique for using the same |
US7657294B2 (en) | 2005-08-08 | 2010-02-02 | Nellcor Puritan Bennett Llc | Compliant diaphragm medical sensor and technique for using the same |
US7904130B2 (en) | 2005-09-29 | 2011-03-08 | Nellcor Puritan Bennett Llc | Medical sensor and technique for using the same |
DE102006004415A1 (en) | 2006-01-31 | 2007-08-09 | Up Management Gmbh & Co Med-Systems Kg | Apparatus for evaluating a hemodynamic condition of a patient using cardiopulmonary interaction |
-
2009
- 2009-03-25 US US12/411,014 patent/US8221319B2/en active Active
-
2010
- 2010-03-16 EP EP10710136.2A patent/EP2410904B1/en not_active Not-in-force
- 2010-03-16 WO PCT/US2010/027508 patent/WO2010111073A1/en active Application Filing
Patent Citations (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6099481A (en) * | 1997-11-03 | 2000-08-08 | Ntc Technology, Inc. | Respiratory profile parameter determination method and apparatus |
WO2002075289A2 (en) * | 2001-03-16 | 2002-09-26 | Nellcor Puritan Bennett Incorporated | Method and apparatus for improving the accuracy of noninvasive hematocrit measurements |
US20040260186A1 (en) * | 2002-02-22 | 2004-12-23 | Dekker Andreas Lubbertus Aloysius Johannes | Monitoring physiological parameters based on variations in a photoplethysmographic signal |
US20060058691A1 (en) * | 2004-09-07 | 2006-03-16 | Kiani Massi E | Noninvasive hypovolemia monitor |
WO2006086085A2 (en) * | 2004-12-28 | 2006-08-17 | Hypermed, Inc. | Hyperspectral/multispectral imaging in determination, assessment and monitoring of systemic physiology and shock |
WO2008073855A2 (en) * | 2006-12-09 | 2008-06-19 | Masimo Corporation | Plethysmograph variability processor |
US20080200775A1 (en) * | 2007-02-20 | 2008-08-21 | Lynn Lawrence A | Maneuver-based plethysmographic pulse variation detection system and method |
US20090076462A1 (en) * | 2007-09-13 | 2009-03-19 | Kiani Massi E | Fluid titration system |
Cited By (14)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP2301613A1 (en) * | 2009-09-29 | 2011-03-30 | General Electric Company | Method, arrangement and apparatus for assessing fluid balance status of a subject |
US8776792B2 (en) | 2011-04-29 | 2014-07-15 | Covidien Lp | Methods and systems for volume-targeted minimum pressure-control ventilation |
WO2013027151A1 (en) * | 2011-08-25 | 2013-02-28 | Koninklijke Philips Electronics N.V. | Method and apparatus for controlling a ventilation therapy device |
US9402573B2 (en) | 2012-08-22 | 2016-08-02 | Covidien Lp | System and method for detecting fluid responsiveness of a patient |
US9060745B2 (en) | 2012-08-22 | 2015-06-23 | Covidien Lp | System and method for detecting fluid responsiveness of a patient |
US9357937B2 (en) | 2012-09-06 | 2016-06-07 | Covidien Lp | System and method for determining stroke volume of an individual |
US9241646B2 (en) | 2012-09-11 | 2016-01-26 | Covidien Lp | System and method for determining stroke volume of a patient |
US10448851B2 (en) | 2012-09-11 | 2019-10-22 | Covidien Lp | System and method for determining stroke volume of a patient |
US11445930B2 (en) | 2012-09-11 | 2022-09-20 | Covidien Lp | System and method for determining stroke volume of a patient |
WO2014043299A1 (en) * | 2012-09-12 | 2014-03-20 | Covidien Lp | Systems and methods for determining fluid responsiveness |
WO2014043302A1 (en) * | 2012-09-12 | 2014-03-20 | Covidien Lp | Systems and methods for determining fluid responsiveness |
US11058303B2 (en) | 2012-09-14 | 2021-07-13 | Covidien Lp | System and method for determining stability of cardiac output |
US8977348B2 (en) | 2012-12-21 | 2015-03-10 | Covidien Lp | Systems and methods for determining cardiac output |
US11324954B2 (en) | 2019-06-28 | 2022-05-10 | Covidien Lp | Achieving smooth breathing by modified bilateral phrenic nerve pacing |
Also Published As
Publication number | Publication date |
---|---|
US8221319B2 (en) | 2012-07-17 |
EP2410904B1 (en) | 2016-01-13 |
EP2410904A1 (en) | 2012-02-01 |
US20100249559A1 (en) | 2010-09-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8221319B2 (en) | Medical device for assessing intravascular blood volume and technique for using the same | |
US11904095B2 (en) | Systems and methods for assisting patient airway management | |
US9414769B2 (en) | Method for determining hemodynamic effects | |
US8801619B2 (en) | Photoplethysmography for determining ventilation weaning readiness | |
US11247009B2 (en) | Anomaly detection device and method for respiratory mechanics parameter estimation | |
US8670811B2 (en) | Pulse oximetry system for adjusting medical ventilation | |
US20160045154A1 (en) | Sleep apnea | |
JP2019509791A (en) | Enhancement of respiratory parameter estimation and asynchronous detection algorithm through the use of central venous pressure manometry | |
JP2009533199A (en) | Method and apparatus for controlling respiration | |
CN112996434B (en) | Capacity reactivity assessment method and medical equipment | |
US11141553B2 (en) | Ventilation control system and method utilizing patient oxygen saturation | |
US11547784B2 (en) | System for CO2 removal | |
US20140073890A1 (en) | Systems and methods for determining fluid responsiveness | |
CN116685368A (en) | Medical equipment system and ventilation treatment auxiliary equipment | |
WO2017192077A1 (en) | Capnotracking of cardiac output or effective pulmonary blood floow during mechanical ventilation | |
CN112384263B (en) | System for assisting blood gas exchange by means of artificial respiration and extracorporeal blood gas exchange and system operating according to the method | |
US20160150997A1 (en) | Method, device and system for determining and utilizing etco2 to paco2 gradient | |
US20220378323A1 (en) | Estimation of mixed venous oxygen saturation | |
Lizza et al. | 680: RISK FACTORS FOR DEATH FROM VENTILATOR-ASSOCIATED PNEUMONIA IN THE UNITED STATES FROM 2008–2011 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 10710136 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2010710136 Country of ref document: EP |
|
NENP | Non-entry into the national phase |
Ref country code: DE |