WO1995000074A1 - Blood pressure measuring apparatus - Google Patents

Blood pressure measuring apparatus Download PDF

Info

Publication number
WO1995000074A1
WO1995000074A1 PCT/GB1994/001332 GB9401332W WO9500074A1 WO 1995000074 A1 WO1995000074 A1 WO 1995000074A1 GB 9401332 W GB9401332 W GB 9401332W WO 9500074 A1 WO9500074 A1 WO 9500074A1
Authority
WO
WIPO (PCT)
Prior art keywords
pressure
artery
measuring
subject
movement
Prior art date
Application number
PCT/GB1994/001332
Other languages
French (fr)
Inventor
Samuel Nathaniel Olalekan Akinyemi
Graham Keith Ablett
Original Assignee
Akinyemi Samuel Nathaniel Olal
Graham Keith Ablett
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Akinyemi Samuel Nathaniel Olal, Graham Keith Ablett filed Critical Akinyemi Samuel Nathaniel Olal
Priority to AU69769/94A priority Critical patent/AU6976994A/en
Publication of WO1995000074A1 publication Critical patent/WO1995000074A1/en

Links

Classifications

    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B8/00—Diagnosis using ultrasonic, sonic or infrasonic waves
    • A61B8/04—Measuring blood pressure
    • 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
    • A61B5/021—Measuring pressure in heart or blood vessels
    • A61B5/022—Measuring pressure in heart or blood vessels by applying pressure to close blood vessels, e.g. against the skin; Ophthalmodynamometers

Definitions

  • the present invention relates to blood pressure measuring apparatus and its method of use in the measurement of blood pressure variables of a subject.
  • a known blood pressure measuring apparatus uses an inflatable cuff connected to a manometer.
  • the cuff is wrapped around the arm of a subject and inflated sufficiently to occlude the blood flow in the main blood vessel of the arm.
  • the inflation pressure is then slowly released to identify when a pulse returns after occlusion.
  • the manometer readings indicate the systolic and diastolic blood pressures of the subject.
  • blood pressure measuring apparatus comprising:- movement sensing means for measuring movement of an artery in a subject; means for applying a pressure to the artery; and pressure sensing means capable of measuring the applied pressure according to changes in amplitude of pressure pulses derived from the artery.
  • artery can encompass blood carrying vessels which are pulsating.
  • the pressure sensing means measures the applied pressure at the maximum amplitude of pressure pulses derived from the artery.
  • the pressure sensor means may take any suitable form but in the preferred embodiments comprises a strain gauge arrangement, using for example a Wheatstone bridge arrangement. Alternatively the pressure sensor may comprise a hall effect sensor.
  • the movement sensing means preferably comprises a Doppler transmitter and receiver arrangement adapted to measure movement of an artery wall.
  • the apparatus preferably includes a marker located for assisting correct positioning of the movement sensor means relative to the artery.
  • the pressure applying means comprises a compressible vesicle having a surface for engaging the subject and a means for compressing the vesicle.
  • a method for determining blood pressure variables of a subject comprising the steps of:- a) measuring movement of an artery in a subject; b) applying a pressure to the artery; and c) measuring the applied pressure according to changes in amplitude of pressure pulses generated by the artery.
  • the maximum pressure fluctuation amplitude serves as a reference point at which values can be taken from the vessel sensor means and the pressure sensor for determining actual values of the systolic and diastolic blood pressures within the vessel from calibration factors.
  • Figure 1 shows schematic and part cross-sectional view of the main components of pressure reading apparatus according to a preferred embodiment of the invention
  • Figure 2 is a schematic view of a standard Doppler apparatus according to a preferred embodiment of the invention positioned in the proximity of a blood vessel;
  • Figure 3 shows a gr: ph illustrating the periodic movement of the wall of a pulsating artery
  • Figure 4 shows a graph of Pressure Fluctuation Amplitude against actual values of measured Pulse Pressure
  • Figure 5 shows a graph of Pressure Fluctuation Amplitude against Applied Pressure
  • Figure 6 shows a graph of Experimental Systolic/Diastolic Pressure against Applied Pressure.
  • Figure 1 shows a schematic view of a blood pressure measuring apparatus of one embodiment of the present invention.
  • the apparatus has a sensing portion 1 connected to an adjustable strap 11 so that the apparatus can be secured firmly to a wrist 7 of a subject whose blood pressure is to be measured.
  • the sensing portion 1 has a casing which includes a pressure applying portion in the form of a compressible vesicle 2 filled with fluid.
  • a plunger 3 is slidably received within the sensing portion casing and can be moved towards the vesicle by way of a rotatable handle 4 which is in threaded interengagement with the casing. As a result of rotation of the handle 4, the plunger can press against the vesicle to increase the pressure generated within the vesicle 2 that is transferred to an artery 6 in the wrist 7.
  • Sensors 5 and 5a located within the vesicle measure certain pressure variables within the vesicle as explained hereinafter.
  • a Doppler arrangement in the form of a transmitter 8 and receiver 9 are also located inside the vesicle for measuring pulsation movements of the wall of the artery 6 as shown in figure 2.
  • the casing of the sensing portion 1 has a marker 13 to assist correct positioning thereof over the artery 6.
  • a microprocessor 10 is connected to operate the ultrasound generator and to receives outputs from the receiver 9 and the sensors 5 and 5a and the values of the diastolic and systolic blood pressure are indicated on a display 12 provided on the surface of the casing.
  • Figure 3 illustrates a curve of pressure against time which can be detected using a known Doppler transmitter and receiver arrangement located above an artery in a wrist.
  • the correct position of the Doppler arrangement is obtained by palpating the wrist in a conventional manner.
  • ultrasound waves generally have a frequency of 5-10 MHz
  • the Doppler effect can be effectively used to measure movement of an arterial wall in pulsatile blood flow.
  • the Doppler arrangement can thus generate a plot of the artery wall movement against time. Since the artery wall movement is proportional to the pressure fluctuation with the artery, the plot gives a representation of the artery pressure fluctuation, i.e. between the systolic and diastolic pressures.
  • the amplitude of this curve represents the pulse pressure R which is the systolic pressure S minus the diastolic pressure D represented in units of the Doppler arrangement. It does not give the values of R in the normal units of millimetres of mercury (mm Hg) .
  • the Doppler arrangement is effectively used to define the rate of blood flow through an artery in terms of pulse pressure and heart rate. This flow is a representation of the cardiac output.
  • the wrist of a subject is palpated and the location of the artery is marked on the wrist. Then, the apparatus is strapped onto the wrist with the marker 13 located above artery location mark made.
  • the Doppler arrangement of transmitter 8 and receiver 9 are ideally positioned to sense movement of the artery wall 6.
  • the basis of the calibration using figure 4 is contained in software algorithms of the microprocessor 10. Furthermore, this calibration broadly takes into account variables between subjects, for example sex, nationality, weight, etc. It will be apparent that the basis of the calibration contained in the microprocessor can be more elaborate using various correction factors related to these variables which are empirically derived.
  • the Doppler arrangement is activated and the output from the receiver 9 is relayed to the microprocessor 10. The output from the receiver 9 is an indication of the pulse pressure R.
  • Pressure is then applied to the vesicle by rotating handle 4 so as to move the plunger 3 to compress the vesicle 2.
  • the pressure of the vesicle is transferred to the wrist and the amplitude of the pressure pulsation is monitored by pressure sensor 5a.
  • the general value of the pressure within the vesicle is monitored by the sensor 5.
  • the output from both sensors is relayed to the microprocessor 10 for processing.
  • the microprocessor 10 detects a maximum in the output of the sensor 5a and at this point the output of the pressure sensor 5 is stored. Assuming the apparatus has been calibrated for systolic pressure, this output is a representation of the systolic pressure S.
  • the apparatus is capable of considerable modification, the details of which will be readily apparent to a person skilled in the art.
  • a manual handle 4 is illustrated, this can be automated under the control of the microprocessor 10.
  • other arrangements of applying pressure to the vesicle 2 can be used.
  • sensors 5 and 5a are shown, they can be incorporated to be a single sensor detecting the general pressure within the vesicle as well as the amplitude of the pressure pulsation.
  • the sensors 5, 5a may take any suitable form, e.g., standard unbonded strain gauges or standard audio-frequency transformer (inductor or capacitor variety) or hrll effect devices.
  • the apparatus can also be arranged to detect other parameters on the basis of the outputs from receiver 9 and sensors 5 and 5a, for example pulse or the mean arterial blood pressure MAP, where

Abstract

The present invention relates to a blood pressure measuring apparatus for determining for example the systolic and diastolic blood pressures of a subject. The apparatus comprises movement sensing means (8, 9) for measuring the movement of an artery (6) in a subject (7), means (2, 3, 4) for applying pressure to the artery and pressure sensing means (5, 5a) capable of measuring the applied pressure according to changes in amplitude of pressure pulses derived from the artery.

Description

BLOOD PRESSURE MEASURING APPARATUS
The present invention relates to blood pressure measuring apparatus and its method of use in the measurement of blood pressure variables of a subject.
In the field of medicine, it is common and useful to measure the arterial blood pressure of a subject, in particular, the systolic pressure S and diastolic blood pressure D. A known blood pressure measuring apparatus uses an inflatable cuff connected to a manometer. The cuff is wrapped around the arm of a subject and inflated sufficiently to occlude the blood flow in the main blood vessel of the arm. The inflation pressure is then slowly released to identify when a pulse returns after occlusion. The manometer readings indicate the systolic and diastolic blood pressures of the subject.
This type of known apparatus is however somewhat rudimentary and open to operator error. For example, it is difficult to accurately and consistently identify when the manometer readings should be taken so that only skilled operators can effectively use the apparatus. Also the requirement to restrict and occlude the blood flow can cause serious discomfort and even injury, particularly to the elderly and infirm.
It is an object of the present invention to provide an improved blood pressure measuring apparatus and associated method of use which seek to overcome the disadvantages of prior devices and their corresponding methods of use.
According to a first aspect of the present invention there is provided blood pressure measuring apparatus comprising:- movement sensing means for measuring movement of an artery in a subject; means for applying a pressure to the artery; and pressure sensing means capable of measuring the applied pressure according to changes in amplitude of pressure pulses derived from the artery.
It will be appreciated that artery can encompass blood carrying vessels which are pulsating.
Preferably, the pressure sensing means measures the applied pressure at the maximum amplitude of pressure pulses derived from the artery.
The pressure sensor means may take any suitable form but in the preferred embodiments comprises a strain gauge arrangement, using for example a Wheatstone bridge arrangement. Alternatively the pressure sensor may comprise a hall effect sensor.
The movement sensing means preferably comprises a Doppler transmitter and receiver arrangement adapted to measure movement of an artery wall.
The apparatus preferably includes a marker located for assisting correct positioning of the movement sensor means relative to the artery.
In the preferred embodiments the pressure applying means comprises a compressible vesicle having a surface for engaging the subject and a means for compressing the vesicle.
According to a second aspect of the present invention, there is provided a method for determining blood pressure variables of a subject, the method comprising the steps of:- a) measuring movement of an artery in a subject; b) applying a pressure to the artery; and c) measuring the applied pressure according to changes in amplitude of pressure pulses generated by the artery. The maximum pressure fluctuation amplitude serves as a reference point at which values can be taken from the vessel sensor means and the pressure sensor for determining actual values of the systolic and diastolic blood pressures within the vessel from calibration factors.
An embodiment of the present invention will now be described by way of example and with reference to the accompanying drawings, in which:-
Figure 1 shows schematic and part cross-sectional view of the main components of pressure reading apparatus according to a preferred embodiment of the invention;
Figure 2 is a schematic view of a standard Doppler apparatus according to a preferred embodiment of the invention positioned in the proximity of a blood vessel;
Figure 3 shows a gr: ph illustrating the periodic movement of the wall of a pulsating artery;
Figure 4 shows a graph of Pressure Fluctuation Amplitude against actual values of measured Pulse Pressure;
Figure 5 shows a graph of Pressure Fluctuation Amplitude against Applied Pressure; and
Figure 6 shows a graph of Experimental Systolic/Diastolic Pressure against Applied Pressure.
Figure 1 shows a schematic view of a blood pressure measuring apparatus of one embodiment of the present invention.
The apparatus has a sensing portion 1 connected to an adjustable strap 11 so that the apparatus can be secured firmly to a wrist 7 of a subject whose blood pressure is to be measured. The sensing portion 1 has a casing which includes a pressure applying portion in the form of a compressible vesicle 2 filled with fluid. A plunger 3 is slidably received within the sensing portion casing and can be moved towards the vesicle by way of a rotatable handle 4 which is in threaded interengagement with the casing. As a result of rotation of the handle 4, the plunger can press against the vesicle to increase the pressure generated within the vesicle 2 that is transferred to an artery 6 in the wrist 7. Sensors 5 and 5a located within the vesicle measure certain pressure variables within the vesicle as explained hereinafter. A Doppler arrangement in the form of a transmitter 8 and receiver 9 are also located inside the vesicle for measuring pulsation movements of the wall of the artery 6 as shown in figure 2. The casing of the sensing portion 1 has a marker 13 to assist correct positioning thereof over the artery 6. A microprocessor 10 is connected to operate the ultrasound generator and to receives outputs from the receiver 9 and the sensors 5 and 5a and the values of the diastolic and systolic blood pressure are indicated on a display 12 provided on the surface of the casing.
Figure 3 illustrates a curve of pressure against time which can be detected using a known Doppler transmitter and receiver arrangement located above an artery in a wrist. The correct position of the Doppler arrangement is obtained by palpating the wrist in a conventional manner. As ultrasound waves generally have a frequency of 5-10 MHz, the Doppler effect can be effectively used to measure movement of an arterial wall in pulsatile blood flow. The Doppler arrangement can thus generate a plot of the artery wall movement against time. Since the artery wall movement is proportional to the pressure fluctuation with the artery, the plot gives a representation of the artery pressure fluctuation, i.e. between the systolic and diastolic pressures. The amplitude of this curve represents the pulse pressure R which is the systolic pressure S minus the diastolic pressure D represented in units of the Doppler arrangement. It does not give the values of R in the normal units of millimetres of mercury (mm Hg) .
From previous work described in WO 92/22871 it is possible to state the following. The Doppler arrangement is effectively used to define the rate of blood flow through an artery in terms of pulse pressure and heart rate. This flow is a representation of the cardiac output. Similarly, the use of conventional techniques to measure the systolic pressure S and the diastolic pressure D to obtain pulse pressure at the same heart rate is also a measurement of the cardiac output. Since these are then equivalent, experimentally determined values of R = S - D can be equated to values of R obtained by the Doppler arrangement so that the units of measurement of the Doppler arrangement can be calibrated. Figure 4 illustrates such a calibration. Since it is a straight line having the formula y = x + c, measurements using the Doppler arrangement can be converted to real values of R once the constants m and c have been experimentally derived.
However, whilst useful values of R in units of millimetres of mercury (mm Hg) can be obtained in this way, the results do not give an indication of the absolute values of systolic pressure S and diastolic pressure D.
The following effect has been noted. If a vesicle contacts the skin above an artery and a pressure is applied to the vesicle, which pressure is transferred to the artery via the skin, there is a pulsation in the pressure of the vesicle. As the transferred pressure is increased by increasing the pressure of the vesicle, the amplitude of the pulsation increases until the pressure starts to occlude the artery. At this point, the amplitude of pulsation starts to drop as the artery becomes progressively occluded. This is illustrated in figure 5.
Referring to Figure 6, it has been found that there is an inverse relationship between the systolic pressure S or diastolic pressure D and the pressure of the vesicle. Thus, the higher the value of the systolic or diastolic pressure, the lower the applied pressure needs to be for the above described maximum pulsation amplitude to occur. Accordingly, it is possible to calibrate so that the value of applied pressure at which the maximum amplitude occurs can be converted to an absolute value of systolic or diastolic pressure. Thus, by using this effect in combination with the Doppler arrangement, it is possible to provide an apparatus which can be calibrated to given absolute values of the systolic pressure and diastolic pressure.
To use the apparatus of the present invention, the wrist of a subject is palpated and the location of the artery is marked on the wrist. Then, the apparatus is strapped onto the wrist with the marker 13 located above artery location mark made.
At this position, the Doppler arrangement of transmitter 8 and receiver 9 are ideally positioned to sense movement of the artery wall 6. The basis of the calibration using figure 4 is contained in software algorithms of the microprocessor 10. Furthermore, this calibration broadly takes into account variables between subjects, for example sex, nationality, weight, etc. It will be apparent that the basis of the calibration contained in the microprocessor can be more elaborate using various correction factors related to these variables which are empirically derived. The Doppler arrangement is activated and the output from the receiver 9 is relayed to the microprocessor 10. The output from the receiver 9 is an indication of the pulse pressure R.
Pressure is then applied to the vesicle by rotating handle 4 so as to move the plunger 3 to compress the vesicle 2. The pressure of the vesicle is transferred to the wrist and the amplitude of the pressure pulsation is monitored by pressure sensor 5a. The general value of the pressure within the vesicle is monitored by the sensor 5. The output from both sensors is relayed to the microprocessor 10 for processing.
As the handle 4 continues to be turned to increase the applied pressure in the vesicle, the microprocessor 10 detects a maximum in the output of the sensor 5a and at this point the output of the pressure sensor 5 is stored. Assuming the apparatus has been calibrated for systolic pressure, this output is a representation of the systolic pressure S.
The microprocessor 10 processes the values of the outputs from the receiver 9 and the sensor 5 to give a value of S according to the output value of the sensor 5 and a value of D = S - R according to output value of the receiver 9. The results can then indicated on display 12.
It will be apparent that the apparatus is capable of considerable modification, the details of which will be readily apparent to a person skilled in the art. For example, whilst a manual handle 4 is illustrated, this can be automated under the control of the microprocessor 10. Alternatively, other arrangements of applying pressure to the vesicle 2 can be used. In addition, whilst separate sensors 5 and 5a are shown, they can be incorporated to be a single sensor detecting the general pressure within the vesicle as well as the amplitude of the pressure pulsation. The sensors 5, 5a may take any suitable form, e.g., standard unbonded strain gauges or standard audio-frequency transformer (inductor or capacitor variety) or hrll effect devices. The apparatus can also be arranged to detect other parameters on the basis of the outputs from receiver 9 and sensors 5 and 5a, for example pulse or the mean arterial blood pressure MAP, where
MAP = ((S - D) / 3) + D

Claims

Claims:
1. Blood pressure measuring apparatus comprising:- movement sensing means for measuring movement of an artery in a subject; means for applying a pressure to the artery; and pressure sensing means capable of measuring the applied pressure according to changes in amplitude of pressure pulses derived from the artery.
2. Apparatus according to claim 1 wherein the pressure sensing means measures the applied pressure at the maximum amplitude of pressure pulses derived from the artery.
3. Apparatus according to claim 1 or 2 wherein the pressure reading apparatus comprises a strain gauge arrangement.
4. Apparatus according to claim 1 or 2 wherein the pressure reading apparatus comprises a hall effect sensor.
5. Apparatus according to any preceding claim wherein the movement sensing means comprises a Doppler transmitter and receiver arrangement.
6. Apparatus according to any preceding claim including a marker, the marker being located for assisting correct positioning of the movement sensor means relative to the artery.
7. Apparatus according to any preceding claim wherein the pressure applying means comprises a compressible vesicle having a surface for engaging the subject and a means for compressing the vesicle.
8. A method for determining blood pressure variables of a subject, the method comprising the steps of:- a) measuring movement of an artery in a subject; b) applying a pressure to the artery; and c) measuring the applied pressure according to changes plitude of pressure pulses generated by the artery.
PCT/GB1994/001332 1993-06-23 1994-06-21 Blood pressure measuring apparatus WO1995000074A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU69769/94A AU6976994A (en) 1993-06-23 1994-06-21 Blood pressure measuring apparatus

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9312962.5 1993-06-23
GB939312962A GB9312962D0 (en) 1993-06-23 1993-06-23 An indirect pulse pressure manometer

Publications (1)

Publication Number Publication Date
WO1995000074A1 true WO1995000074A1 (en) 1995-01-05

Family

ID=10737654

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1994/001332 WO1995000074A1 (en) 1993-06-23 1994-06-21 Blood pressure measuring apparatus

Country Status (3)

Country Link
AU (1) AU6976994A (en)
GB (1) GB9312962D0 (en)
WO (1) WO1995000074A1 (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1999063890A1 (en) * 1998-06-12 1999-12-16 Children's Medical Center Corporation Non-invasive in vivo pressure measurement
WO2001000087A1 (en) * 1999-06-29 2001-01-04 Tensys Medical, Inc. Method and apparatus for the noninvasive determination of arterial blood pressure
US6251080B1 (en) * 1999-05-13 2001-06-26 Del Mar Medical Systems, Llc Self contained ambulatory blood pressure cincture
WO2003007820A2 (en) * 2001-07-18 2003-01-30 Cardiosonix Ltd. An ultrasonic transducer probe and a measurement device utilizing the same
WO2003065878A2 (en) 2002-02-05 2003-08-14 Tensys Medical, Inc. Method and apparatus for non-invasively measuring hemodynamic parameters using parametrics
US7048691B2 (en) 2000-03-23 2006-05-23 Tensys Medical, Inc. Method and apparatus for assessing hemodynamic parameters within the circulatory system of a living subject
CN103110431A (en) * 2012-09-12 2013-05-22 中国科学院深圳先进技术研究院 Noninvasive continuous blood pressure measurement device and method
US9247886B2 (en) 2004-10-07 2016-02-02 Tensys Medical, Inc. Compact apparatus and methods for non-invasively measuring hemodynamic parameters
EP3089660A4 (en) * 2014-01-03 2017-08-09 William R. Fry Ultrasound-guided non-invasive blood pressure measurement apparatus and methods
US10285598B2 (en) 2006-05-13 2019-05-14 United States Gtm Medical Devices Continuous positioning apparatus and methods
US10952675B2 (en) 2007-10-12 2021-03-23 Shangyi Medical Technology (Hangzhou) Co., Ltd Apparatus and methods for non-invasively measuring a patient's arterial blood pressure

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3527197A (en) * 1966-04-19 1970-09-08 Southwest Res Inst Indirect blood pressure measurement
US3885551A (en) * 1971-04-01 1975-05-27 Hoffmann La Roche Artifact rejection for blood pressure monitoring
DE3345739A1 (en) * 1983-12-17 1985-07-04 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., 8000 München Device for recording and displaying circulatory parameters, to be worn on the wrist
EP0299827A1 (en) * 1987-07-03 1989-01-18 Gérard Boutin Device for measuring the blood pressure in a superficial artery
EP0456844A1 (en) * 1990-01-19 1991-11-21 Nihon Kohden Corporation Non-invasive automatic blood pressure measuring apparatus
WO1992007508A1 (en) * 1990-10-31 1992-05-14 Medwave, Inc. Noninvasive, non-occlusive blood pressure method and apparatus

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3527197A (en) * 1966-04-19 1970-09-08 Southwest Res Inst Indirect blood pressure measurement
US3885551A (en) * 1971-04-01 1975-05-27 Hoffmann La Roche Artifact rejection for blood pressure monitoring
DE3345739A1 (en) * 1983-12-17 1985-07-04 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V., 8000 München Device for recording and displaying circulatory parameters, to be worn on the wrist
EP0299827A1 (en) * 1987-07-03 1989-01-18 Gérard Boutin Device for measuring the blood pressure in a superficial artery
EP0456844A1 (en) * 1990-01-19 1991-11-21 Nihon Kohden Corporation Non-invasive automatic blood pressure measuring apparatus
WO1992007508A1 (en) * 1990-10-31 1992-05-14 Medwave, Inc. Noninvasive, non-occlusive blood pressure method and apparatus

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
N.SCLATER: "DOPPLER TRANCEIVER PUTS FINGER ON BLOOD PRESSURE", PRODUCT ENGINEERING, vol. 41, no. 1, January 1970 (1970-01-01), NEW YORK US, pages 109 *

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6086533A (en) * 1998-06-12 2000-07-11 Children's Medical Center Corporation Non-invasive in vivo pressure measurement
WO1999063890A1 (en) * 1998-06-12 1999-12-16 Children's Medical Center Corporation Non-invasive in vivo pressure measurement
US6251080B1 (en) * 1999-05-13 2001-06-26 Del Mar Medical Systems, Llc Self contained ambulatory blood pressure cincture
WO2001000087A1 (en) * 1999-06-29 2001-01-04 Tensys Medical, Inc. Method and apparatus for the noninvasive determination of arterial blood pressure
US6471655B1 (en) 1999-06-29 2002-10-29 Vitalwave Corporation Method and apparatus for the noninvasive determination of arterial blood pressure
US6514211B1 (en) 1999-06-29 2003-02-04 Tensys Medical, Inc. Method and apparatus for the noninvasive determination of arterial blood pressure
US7503896B2 (en) 1999-06-29 2009-03-17 Tensys Medical, Inc. Method and apparatus for the noninvasive assessment of hemodynamic parameters including blood vessel location
US7048691B2 (en) 2000-03-23 2006-05-23 Tensys Medical, Inc. Method and apparatus for assessing hemodynamic parameters within the circulatory system of a living subject
US8328727B2 (en) 2000-03-23 2012-12-11 Tensys Medical, Inc. Method and apparatus for assessing hemodynamic parameters within the circulatory system of a living subject
WO2003007820A2 (en) * 2001-07-18 2003-01-30 Cardiosonix Ltd. An ultrasonic transducer probe and a measurement device utilizing the same
WO2003007820A3 (en) * 2001-07-18 2003-05-15 Cardiosonix Ltd An ultrasonic transducer probe and a measurement device utilizing the same
EP1478269A2 (en) * 2002-02-05 2004-11-24 Tensys Medical, Inc. Method and apparatus for non-invasively measuring hemodynamic parameters using parametrics
EP1478269A4 (en) * 2002-02-05 2008-03-19 Tensys Medical Inc Method and apparatus for non-invasively measuring hemodynamic parameters using parametrics
WO2003065878A2 (en) 2002-02-05 2003-08-14 Tensys Medical, Inc. Method and apparatus for non-invasively measuring hemodynamic parameters using parametrics
US9814398B2 (en) 2002-02-05 2017-11-14 Tensys Medical, Inc. Method and apparatus for non-invasively measuring hemodynamic parameters using parametrics
US9247886B2 (en) 2004-10-07 2016-02-02 Tensys Medical, Inc. Compact apparatus and methods for non-invasively measuring hemodynamic parameters
US10285598B2 (en) 2006-05-13 2019-05-14 United States Gtm Medical Devices Continuous positioning apparatus and methods
US10952675B2 (en) 2007-10-12 2021-03-23 Shangyi Medical Technology (Hangzhou) Co., Ltd Apparatus and methods for non-invasively measuring a patient's arterial blood pressure
CN103110431A (en) * 2012-09-12 2013-05-22 中国科学院深圳先进技术研究院 Noninvasive continuous blood pressure measurement device and method
EP3089660A4 (en) * 2014-01-03 2017-08-09 William R. Fry Ultrasound-guided non-invasive blood pressure measurement apparatus and methods

Also Published As

Publication number Publication date
AU6976994A (en) 1995-01-17
GB9312962D0 (en) 1993-08-04

Similar Documents

Publication Publication Date Title
USRE37852E1 (en) Blood pressure monitoring system
US5261414A (en) Blood pressure monitor system
US6814705B2 (en) Arteriosclerosis-degree evaluating apparatus
JP2938234B2 (en) Blood pressure monitor device with finger cuff calibration device
CA2260142A1 (en) Method and apparatus for the non-invasive detection of medical conditions by monitoring peripheral arterial tone
US20090036786A1 (en) Automatic ankle brachial pressure index system
US20080064967A1 (en) System and method of non-invasive blood pressure measurements and vascular parameter detection in small subjects
WO1995000074A1 (en) Blood pressure measuring apparatus
US4660566A (en) Method and apparatus for the non-invasive monitoring of arterial blood pressure waves
EP1400201A1 (en) Arteriostenosis inspecting apparatus
US5042496A (en) Method for measuring blood pressure and a blood-pressure measuring device for carrying out the method
US4649928A (en) Noise-immune blood pressure measurement technique and system
US6808497B2 (en) Blood-pressure measuring apparatus and inferior-and-superior-limb blood-pressure-index measuring apparatus
EP3705033A1 (en) Blood pressure measurement device and control method
US8047997B2 (en) Non-invasive blood pressure monitor apparatus and system
US20040039290A1 (en) Cuff pulse wave detecting apparatus and pulse-wave-propagation-velocity-related information obtaining device
KR102356200B1 (en) Blood Pressure Meter And Method For Measuring Blood Pressure Using The Same
JPWO2004069049A1 (en) Blood pressure pulse wave measuring device and blood pressure pulse wave measuring wearing tool
JPH0529453B2 (en)
EP0246571B1 (en) Electronic blood pressure meter incorporating compensation function for systolic and diastolic blood pressure determinations
JPS61247432A (en) Electronic hemomanometer
US20230181049A1 (en) Blood pressure meter and method for measuring blood pressure using the same
JPH046732Y2 (en)
KR890002763B1 (en) Electronic blood pressure meter
Lacković Inspection and Testing of Noninvasive Blood Pressure Measuring Devices

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AT AU BB BG BR BY CA CH CN CZ DE DK ES FI GB GE HU JP KE KG KP KR KZ LK LU LV MD MG MN MW NL NO NZ PL PT RO RU SD SE SI SK TJ TT UA US UZ VN

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: CA

122 Ep: pct application non-entry in european phase