CA1225849A

CA1225849A - Portable unit for withdrawing blood and other fluids

Info

Publication number: CA1225849A
Application number: CA000451589A
Authority: CA
Inventors: Eberhart Stephan
Original assignee: Individual
Current assignee: Individual
Priority date: 1983-04-12
Filing date: 1984-04-10
Publication date: 1987-08-25
Also published as: ATE32302T1; EP0139706A1; JPH0580216B2; US4696309A; DK581584D0; EP0139706B1; JPS60501692A; DK581584A; WO1984004033A1; DE3313074C2; DE3313074A1

Abstract

PORTABLE UNIT FOR WITHDRAWING BLOOD AND
OTHER BODILY FLUIDS

ABSTRACT
The invention relates to a portable unit for withdrawing blood and other bodily fluids, the said unit consisting of a catheter, a pump and a storage container for the bodily fluid withdrawn. It is the purpose of the invention to design a unit for withdrawing bodily fluids from human and animal probands in such a manner that the said withdrawal may be effected repeatedly at any time, with no need for any person to be in the vicinity of the proband for the purpose of operating the unit.
The invention consists in that the control-device may be switched on by remote-control; in that reservoirs are provided for the bodily fluids withdrawn, wherein a plurality of bodily-fluid samples may be stored; in that a flushing and filling device is provided for the pump, the catheter and the duct-system running from the pump to the reservoir; in that a valve or system of valves is arranged in front of the reservoir for passing the bodily fluid withdrawn and for the flushing and filling fluid for the duct-system;
and in that a control-device for actuating the pump, the flushing and filling device, and the valve or system of valves is provided.

Description

89L~1 FIELD OF THE INVENTION
. .
The invention relates to a portable unit for withdrawing blood and other bodily fl~ids, the said unit consisting of a catheter, a pump and a storage container for the fluid withdrawn.

BACKGROUND OF THE INVENTION
The simplest known way of withdrawing blood is by means of a cylinder provided at one end with a hollow needle and containing a piston. The piston rod passes out of the other end of the cylinder and terminates in a ring. For the purpose of withdrawing blood, the cylinder is held with the fingers of one hand, while the thumb of the said hand is passed through the said ring. There is also a very wide variety of more complex developments of this very simple device, the most complex being mounted upon a cart.
When blood is taken directly by means of these devices from a proband, psychic influences or physical conditions, for example, at times have a detrimental effect upon the withdrawal of blood. Although it is possible, with these more complex units, to withdraw blood repeatedly, they cannot be carried by the proband.
In the field of medicine, there is a need for information regarding blood, its constituents, the substances it contains, and the physiological and pathological changes occurring. This information may be obtalned by taking and analysing blood-samples and by inserting measuring sensors and 27 catheters. Where blood samples are obtained directly by puncture, catheterization or the like, psychic influencing of the proband may lead to changes in blood values. Furthermore, such methods :

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can be used only to a limited extent in many investigations which are carried out under stress, for example in the case of track-training, rehabilitation patients, athletes and the like, and stress tests on animals, since the activity in question must be interrupted in order to withdraw blood and blood values may change at these times. Under certain conditions, e.g.,pilots in simulated or actual flight situations, stress tests on freely moving animals and the like, such tests are quite impossible.
Blood and other bodily-fluid investigations of this kind, carried out on human beings and animals under specific stresses, require a portable wi~hdrawing unit which will take samples at times which may be freely selected according to circumstances, or may be predetermined, so that the presence of a person to operate the unit is unnecessary.
It is the purpose of the invention to design a unit for withdrawing bodily fl~ids from human and animal probands in such a manner that the withdrawal of blood may be carried out repeatedly at any desired times, with no need for a person in the vicinity of the proband to operate the unit.
The portable withdrawing unit according to the invention is characterized in that the control-device (for the pump-drive among other things) is adapted to be switched on and off if necessary, by remote control; in that a storage means is provided for the bodily fluid withdrawn, in which a plurality of samples may be stored; in that a flushing and filling device is provided for the pump, the catheter and the duct-system running f`rom the 27 pump to the storage means; in that a valve or system of valves is arranged in front of the storage means for passing the bodily fluid withdrawn and for the flushing and filling fluid for the 1uct system; and in that a control device is provided for actuating the said flushing and filling device and the valve or system of valves.
A withdrawing unit of this kind may be accommodated in a housing with a belt. The remote control, preferably a radio-remote-control makes it possible to feed pulses to the unit, either in accordance with a programme or with instructions issued by a distant person, the said pulses activating the pump-drive and thus effecting a withdrawal of bodily fluid and subsequent flushing of the duct-system of the unit, the pump and the catheter. One particular advantage of this device is that the duct-system as a whole, and the catheter, are at all times filled with fluid and are therefore free of gas, since the flushing fluid is also the filling fluid for the catheter. For the sake of simplicity,the term flushing fluid will be used hereinafter, instead of flushing and filling fluid. Quite large numbers of ; bodily-fluid samples may be stored in the storage container of the unit and the operating units may be largely miniaturized.
~ This miniaturization makes it possible to use a very small source ; 20 of power in the form of an electrical battery or accumulator.
If the storage container comprises a plurality of chambers for the accommodation of samples, it is desirable to arrange in front of it a multi-way valve in which each setting runs to a chamber for the accommodation of a sample and one setting is provided to carry away the flushing fluid. This design makes it possible, for example when the activities of a human 27 being or an animal are being observed, to withdraw blood repeatedly, without the proband being aware of it or being influenced thereby. In ~this way it is possible to draw ~onclusions, for example as to the effect of various organs upon the blood before the during specific bodily and mental stresses.
In this example of embodiment it is desirable for the multi-way valve to contain a valve, preferably a rotary valve comprising a duct, the outlet from which may be adjusted to dif~erent apertures, so that consecutive samples of bodily fluid may be passed to different storage chambers. One of these apertures however, does not run to a storage chamber, but allows the flushing fluid to drain away freely. Preferably each second aperture is used to drain the flushing fluid.

The withdrawing unit may, however, also have a storage container of a different design. One design, which is suitable for the desired miniaturization of the unit, consists in that the storage container is in the form of a hose or tube into which a sample of bodily fluid, alternating with a specific quantity of separating gas (e.g., air or an inert gas) which, in the form of bubbles, separate the individual samples of bodily fluid from each other, is introduced after each actuation of the pump; in that a storage container is provided for the buffering fluid; in ~ that a valve or system of valves is arranged in front of the storage container, by means of which a specific quantity of separating gas may be introduced into the storage-container after each sample of bodily ~luid; and in that an additional valve, or system of valves, is provided to feed a flushing medium to, and remove it from, the duct-system, between the pump and the storage container on the one hand and into the pump and catheter on the 27 other hand.

The switching technology of the unit lS simple if the control-unit for the flushing device, the valves associated :; :
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therewith, and/or the valves associated with the storage tank, are activated by a pulse from the remote control and/or the pump.
The supply of flushing fluid is preferably arranged between the multi-way valve and the pump. In this connection it may be desirable to arrange a check-valve between the flushing-fluid feed and the multi-way valve.
In the case of a stationary drive, the radio-remote-control may be replaced by a cable, for example, or if a large centrifuge is used - by a cable and sliding contacts.
The built-in control device may also be used to control other appliances as required, for example recording or storage equipment for physiological or the like data.
The advantages of the invention are, in particular, that repeated withdrawals of bodily fluids can be carried out, even under adverse external conditions, with no psychic stress for the proband, and with no one in the immediate vicinity of the proband.
The withdrawal of bodily fluid is carried out in such a manner that the pump is activated for a specific period of time;
that during a first period of time, the fluid drawn in by the pump is pumped to the free outlet; that the multi-way valve is then set to bring the duct provided in the valve to the aperture running to an empty sample chamber; that, after a further specific period of time, the pump is deactivated in such a position as to allow flow-throagh; that the said multi-way valve is thereupon reset to align the duct in the valve with the free 27 outlet; and that, over a specific period of time, flushing medium is then introduced, on the one hand, lnto the duct-system leading to the multi-way valve and, on the other hand, into the hose-pump and the catheter.

THE DRAWINGS
The essence of the invention is explained hereinafter in greater detail in conjunction with the two examples of embodiment illustrated in the drawing attached hereto, wherein:
Figure 1, shows a withdrawing unit with a storage container comprising a plurality of individual chambers for the accommodation of samples;
lOFigure 2, illustrates a withdrawing unit comprising storage means in the form of a hose.

DESCRIPTION_OF THE PREFERRED EMBODIMENTS_ The withdrawing unit is accommodated in a housing comprising a passage or adaptor 2 to which a permanent catheter ; can be fitted. Bodily fluid is drawn through this catheter, through adaptor 2/ by hose-pump 3 and is passed through a duct 4, check-valve 5, and duct 6 to a rotary multi-way valve 7, housing 71 of which comprises a series of discharge apertures 72, 73, 74, 75, .... , each second aperture 72,74 leading to a different receptacle, e.g., a test-tube for the fluid samples, while each intervening aperture 73,75 leads to a common free outlet.
Arranged in the interior of valve 7 is a slide 76 comprising a duct 77 adapted to connect the said duct to one of apertures 72..75. Slide 7 is preferably a rotary slide with a central inlet and a peripheral outlet communicating - according to the 27 setting of valve - with one of the discharge apertures. At least one of the said discharge apertures in housing 71 leads to duct 78 to perm~t free disoharge of the flushing fluid and of the ~6 :: . :

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~ixture of flushing fluid and bodily fluid which is drawn in with the initial cycle of the hose-pump and is passed through duct-system 4,6 to the rotary multi-way valve.
~ or the purpose of flushing the unit after each individual withdrawal of bodily fluid, a reservoir 9 is provided, whence a line 11 leads, through a solenoid-valve 10, to duct 4. Reservoir 9 is preferably a storage means for fluid, in the form of a gas-and air-free flexible container which collapses during fractional withdrawal of flushing and filling fluid, thus ensuring that the entire catheter-hose system remains free of gàs or air. The flushing fluid is removed, after the solenoid-valve has been opened, through line 19 by the action of pump 3. Where blood is being sampled, the flushing fluid used is a heparinized physiological saline solution. Like pump 3, solenoid-valve 10 and rotary multi-way valve 7 are actuated by a control unit 12 which is triggered by receiver 13, antenna 14 of which captures signals from emitter 15. Electrical power is provided for receiver 13 of control-unit 12, for solenoid-valve 10, and hose-pump 3 by an accummulator 16.
Control-unit 12 is triggered by a pulse from receiver 13. The resulting withdrawal process and subsequent flushing process involve the following individual steps: upon arrival of the pulse triggering control-unit 12, hose-pump 3 is activated, with solenoid-valve 10 closed, through electrical lead 17. This causes fluid to flow from catheter 2 to line 4, through check-valve 5, to line 6 and thence to rotary multi-way valve 7. The 27 setting of this valve is such that duct 77 is slide 76 is aligned with the aperture running to free discharge 78. As a result of this, any flushing solution present in the catheter before the : :

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)odily fluid is withdrawn, and some of the bodily fluid drawn in, is passed to the free discharge (is discarded). After a prede~ermined cycle-time, control unit 12 releases another pulse, through electrical lead 18, to the motor which drives rotary multi-way valve 7, ca~sing the said motor to rotake the slide 76 and thus to move duct 77 thereof into alignment with the first outlet-aperture leading to a receptacle for the sample. The pump is halted before each movement of the slide and is started up again as soon as the slide reaches its new position. During each ln movement there is no pressure in the rotary valve and there is therefore no load upon the sealing surfaces. As soon as receptacle 8 for the sample of bodily fluid has had time to fill, control unit 12 releases a further pulse,through line 18, to the motor of the rotary multi-way valve, allowing flushing fluid to flow through duct 79 to free discharge 78. This pulse also acts, through line 17, upon the hose-pump, bringing it to a halt.
The said pulse also actsj through line 19, upon solenoid-valve 10 which is thus opened for a short time, allowing flushing and filling fluid to enter,through line 119 into duct 4, check-valve ~ 6, and rotary multi-way valve 7. At the same time flushing fluid is also allowed to enter the hose-pump and the catheter. After a specific short time, the solenoid-valve is closed again and the unit is available for the next withdrawal process. The exact setting of the rotary slide is monitored by a light-barrier. The next time bodily fluid is withdrawn, the~rotary valve comes to a halt with its duct 77 in alignment with an outlet-aperture, thus 27 allowing any flushing fluid in the catheter to pass, through line 79, into line 78 and thus to flow ~reely away. During the withdrawal process~ slide 76 is rotated to move duct 77 to ' ~utlet-aperture 74, to allow the next receptacle 8, to which this aperture is connected, to be filled. Thus each time bodily fluid is removed, another receptacle 8 is filled. the motor of the rotary multi-way valve may be in the form of a step-by-step switching mechanism since, between each two ducts leading to two adjacent receptacles 8, there is always a duct leading to duct 78 through which the flushing fluid can flow freely away.
The example of embodiment illustrated in Figure 2 differs substantially from that according to Figure 1, in that rotary multi-way valve 7 is replaced by a three-way valve 20, rotary slide 21 of which comprises a curved duct 22. Furthermore, sample receptacles 8 are replaced by a storage-container in the form of a hose 23. When bodily fluid is to be withdrawn, duct 22 first connects duct 6 to discharge line 78 as a first step.
In the setting corresponding to the second step, it connects duct 6 with hose 23. In a third step it connects hose 23, through duct 24 and solenoid-valve 25, to storage container 26 for the buffering gas. The latter container is a pressurized container in which the separating gas is under high pressure.
?0 In this example of embodiment, control of the withdrawal process is effected as in the case of Fig~re 1. By means of a step-by-step switching mechanism, at a specific moment after the unit has been started up, rotary slide 21 is moved from the setting in which duct 22 connects duct6 with discharge line 78, to the setting in which duct 6 is connected with hose 23. After another period of time, the said step-by-step switching mechanism ~7 again rotates slide 21 through 90 in such a manner that duct 22 connects storage means 2G for the separating gas to hose 23.
Solenoid-valve 2~ is opened for a short time, to allow a specific , - , - : . - ' :

.~Z~;~49 amount of buffering fluid to flow into hose 23. This is followed by two consecutive switching steps, causing slide 21 to rotate through twice 90 , so that duct 22 in rotary slide 21 again connects duct 6 to discharge line 78. Flushing can now be carried out with flushing fluid from the reservoir, : 10 : .: : ., : ~.:
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Claims

1. A portable unit for withdrawing blood and other bodily fluids, the said unit consisting of a catheter, a pump, at least one storage receptacle for bodily fluid withdrawn, an interconnecting duct system and control means therefor, characterized in that the control means for the unit is adapted to be actuated by remote-control; in that a plurality of said receptacles are provided for the bodily fluid withdrawn, wherein a plurality of bodily-fluid samples may be stored; in that a flushing and filling device is provided for flushing the pump, the catheter and the duct-system running from the pump to the receptacles; in that a valve system is arranged upstream of the receptacles for selectively passing the bodily fluid withdrawn and for the passage of flushing and filling fluid for the duct-system; and in that a control-device for actuating the pump, the flushing and filling device, and the valve system is provided.

2. A fluid withdrawing unit according to claim 1, characterized in that said valve system comprises a multi-way valve arranged upstream of said receptacles, each setting of said valve connecting with a selected receptacle for the accommodation of a sample therein; and wherein at least one setting of said multi-way valve is provided for carrying away the flushing fluid.

3. A fluid withdrawing unit according to claim 2, characterized in that said multi-way valve comprises a slide-valve having a duct, the outlet of which may be adjusted to selected discharge apertures.

4. A fluid withdrawing unit according to claim 1, characterized in that said storage receptacles consist of a tube to which, in constant alternation, a sample of bodily fluid and a quantity of separating gas may be passed after each actuation of said pump; in that said valve system includes a distributor valve located upstream of the storage receptacle, whereby a specific quantity of separating gas may be introduced into the storage receptacle after the introduction therein of each sample of bodily fluid; and in that said valve system includes a valve for the introduction of said flushing medium into said duct-system between said pump and said distribution valve.

5. A fluid withdrawing unit according to claim 1, characterized in that remote-control is effected by a radio-remote-control consisting of a transmitter and a receiver.

6. A fluid withdrawing unit according to claim 1, characterized in that said control means for said flushing device, for selected valves of said valve system is adapted to be activated by a remote-control pulse.

7. A fluid withdrawing unit according to claim 1, characterized in that said flushing and filling device is positioned between said valve system and said pump.

8. A fluid withdrawing unit according to claim 1, characterized in that the structural parts thereof are accommodated in a housing provided with a body belt.

12 A method of withdrawing blood and other bodily fluids by means of a catheter or a cannula by use of an apparatus attached to the body of a proband comprising a pump and a storage receptacle for the withdrawn fluids, characterized in that the pump is activated by remote control for a specific time, in that during a first period of time the bodily fluid is pumped to a waste outlet; in that the pump is then halted and a multi-way valve upstream of the storage receptacle is adjusted by remote control in such a manner that a duct arranged in a slide portion of the valve is positioned in front of an opening into a still empty sample-acccommodating receptacle; in that the pump is again set in operation and the sample accommodating receptacle filled with bodily fluid; in that after a further specific period of time the pump is again deactivated; in that the multi-way valve is again adjusted in such a manner that it assumes a setting permitting throughflow; in that the said multi-way valve is thereafter again adjusted so that said duct in the valve-slide is moved into alignment with said waste outlet; in that thereafter flushing medium is fed, for a predetermined period of time into the duct-system of said mutli-way valve and, into said pump and said catheter.

10. A fluid withdrawing unit according to claim 1, characterized in that said storage receptacle is adapted to be cooled.

11. A method of operating a fluid withdrawing unit, according to claim 9, characterized in that cooling is applied to said bodily fluid storage receptacle.

12. The method as set forth in claim 11 characterized in that said receptacle comprises a vessel of extruded length and restricted cross section, to receive a plurality of samples of said fluids, sequentially, including the steps of introducing a separating fluid between each said sample.