GB2050837A

GB2050837A - Haemodialysis

Info

Publication number: GB2050837A
Application number: GB7921723A
Authority: GB
Original assignee: Czech Technical University In Prague
Current assignee: Czech Technical University In Prague
Priority date: 1979-06-19
Filing date: 1979-06-21
Publication date: 1981-01-14
Also published as: FR2459050A1; BE877159A; GB2050837B

Abstract

A device for haemodialysis comprising a haemodialyser (4) through which pass a blood circuit and a dialysing solution circuit. The blood circuit has at its inlet an artery needle (1) and at its outlet a venous needle (6), a blood pump (3) for pumping the blood through the circuit and a venous bag (5) being situated between the two needles. The dialysing solution circuit includes a container (7) for the solution, a chamber (15) including sensors for sensing the temperature, the conductivity and the pressure of the solution before it enters the dialyser, a pump (17) for pumping the solution through the circuit, a haemoglobin detector (18) at the outlet from the pump, and a steriliser (8) for the solution situated downstream of or in the container. The steriliser includes at least two electrodes (9, 10) connected to a source (11) supplying thereto electric current the frequency and amplitude of which are variable in time. The device also comprises an electronic unit (16) for actuating an alarm unit (19). <IMAGE>

Description

SPECIFICATION A device for haemodialysis The invention relates to a device for a haemodialysis provided with: an arterial needle, a set of hoses with a venous bag, a blood pump, a hemodialyzer, a venous needle, a container of dialyzing solution, a conduit for a dialyzing solution, a chamber of sensors of temperature, of conductivity and of pressure of a dialyzing solution, a pump of the dialyzing solution, a haemoglobin detector, an electronic unit and an alarm unit having an acoustic and visual indication.

Hitherto known stationary devices for haemodialysis installed in hospitals are usually supplied from the mains and they depend upon delivery of water under pressure. A dialyzing solution is prepared by means of built-in mixers.

Mobile devices for haemodialysis comprise a container of a dialysis solution, a supply of the electronic part of the device from a transportable power unit and minimum of those parts that must be sterilized. That is why hoses for dialyzing solution may be used once only.

A drawback of hitherto known devices for haemodialysis having a container of a dialyzing solution and being mobile types, reside in a quick concentration increase of microorganisms in the unsterile dialyzing solution. If bacterium contamination in the dialyzing solution exceeds a concentration of 1000 microorganisms/ml, then there exists for a patient a risk of pyrogenic and septic complications. A preparation of a dialyzing solution of a low concentration of microorganisms (under 100/mull) e.g. from a newly destilled water or from water irradiated by a germicide discharge tube, requires much power and that is why it is not possible to do it in a transport means.

Therefore the dialyzing solution is prepared only from water previously examined as to a bacterium content. Such an examination takes much time.

To heat the dialyzing solution in a conventional way by electric current requires much power from the transport means. In case of self-care operation of a device for haemodialysis by a patient who is sleeping or hard of hearing, there is a danger that the patient does not notice the acoustic or visual alarm, and does not rectify the defect in the operation of the device.

Some of the mentioned drawbacks may be obviated by the device for haemodialysis according to the invention which comprises an arterial needle, a set of hoses with a venous bag, a blood pump, a haemodialyzer, a venous needle, a container of a dialyzing solution, a conduit for the dialyzing solution, a chamber of sensors of temperature, of conductivity and of pressure of the dialyzing solution, a pump of the dialyzing solution, a haemoglobin detector, an electronic unit and an alarm unit providing an acoustic and visual indication.

The principle of the haemodialyzing device according to the invention resides in the fact, that in the conduit of the dialyzing solution or in the container of the dialyzing solution there is situated a unit for suppressing the grow of microorganisms in the dialyzing solution (hereinafter: "sterilizer" for short) which comprises two electrodes connected to a source of electric current of frequency and amplitude variable in time. In the conduit of the dialyzing solution there may be situated a heat exchanger connected to a source of waste heat of a transport means. It may be also situated in a container of the dialyzing solution. A source of electric pulses with electrodes connected to the body of a patient may be connected to the output of the alarm unit.

The sterilizer suppresses the growth of microorganisms in the dialyzing solution and so obviates the danger of infection, pyrogenic and septic complications of medical treatment. The sterilizer is advantageous also for stationary devices for haemodialysis with recirculation of the dialyzing solution and for devices with regeneration of the solution. The heating of a dialyzing solution by means of a heat exchanger supplied with a waste heat of the transport means obviates a considerable power consumption from the network of the transport means.

The source of electric pulses with electrodes attached to the patient's body increases the safety during a self-care operation of the device for haemodialysis. In case that a patient who is sleeping or is hard of hearing ignores the visual or acoustic alarm, he is alerted by the electric pulses. The safety of operation may be increased in this way in a clinical operation of a haemodialyzing device in "self-care" operation.

The invention wwill now be described, by way of example, with reference to the accompanying diagrammatic drawing in which a mobile device for haemodialysis is shown.

Blood is guided from the patient's body through an arterial needle 1, a set of hoses 2, a blood pump 3 into a haemodialyzer 4 of a known design. Blood is guided from the haemodialyzer 4 into a venous bag 5, the outlet of which for measuring pressure is connected to a pressure sensor of an electronic unit 16. Blood flows back into the patient's body through a venous needle 6.

The dialyzing solution is guided through a sterilizer 8 (a unit for suppressing the growth of microorganisms) from a container 7 for the dialyzing solution.

The sterilizer 8 comprises at least two electrodes 9 and 10, which are connected to a source 11 of electric current the frequency and amplitude of which are variable in time. After sterilizing, the dialyzing solution passes through a heat exchanger 14 which is supplied with waste heat from a transport means. The heat intake is controlled by means of a valve 25 operated by a heat governor in the electronic unit 16. It is advantageous to locate the sterilizer 8 and the heat exchanger 14 in the container 7 for the dialyzing solution. A conduit 13 for the dialyzing solution is connected to a chamber 15 with sensors. Outlets of the sensors of temperature, conductivity and pressure of the dialyzing solution are connected to the electronic unit 16. The passage of the dialyzing solution through the haemodialyzer 4 is achieved by a pump 17 for the dialyzing solution.

On the outlet of the pump 17 for the dialyzing solution there is situated a haemoglobin detector 18 having its electric output connected to the electronic unit 16.

To the output of the electronic unit 16 is connected an alarm unit 19 with an acoustic alarm 24 and visual alarm 23 which are switched on if there is a defect in operation. To the output of the alarm unit 19 is connected a source 20 of electric pulses with electrodes 21 and 22 connected to the patient's body.

Electric pulses will alert the patient in case that he does not notice the visual or acoustic signal. It is advantageous to arrange the alarm unit 19 so, that the source 20 of electric pulses may be switched on later than the acoustic and visual alarms.

In the described embodiment of the device for haemodialyses there is used a sterilizer 8 having non-rusting electrodes 9 and 10 and operating at current density of 25 A/M2 and frequency range of the source 11 of 0,1 Hz to 800 Hz.

The heat exchanger 14 is supplied from the water circuit of a radiator of a passenger-car. The supply of the heat exchanger 14 is controlled by means of an electromagnetic valve 25 connected to the electronic unit 16 and to the temperature governor placed inside it.

The source 20 of electric pulses is designed for an instantaneous output adjustable within the range of 0,1 Wto 1,0 W.

The chamber 15 with sensors is removable out of the device, and is immersed in a sterilizing bath during sterilization. The conduit 13 of the dialyzing solution is designed for one application only.

The device for haemodialysis is designed for home and weekend dialysis as well as for quick action in case of accidents in terrain conditions.

The invention has been described with reference to one preferred embodiment, but it is to be expressly understood that the invention may be carried out in other embodiments within the scope of the appended claims.

Claims

1. A device for haemodialysis comprising a haemodialyser, a blood circuit passing through the haemodialyser and having at its inlet an artery needle and at its outlet a venous needle, a blood pump for pumping the blood through the circuit and a venous bag being situated between the two needles, and a dialysing solution circuit passing through the haemodialyser and including a contain error the solution, a chamber including sensors for sensing the temperature, the conductivity and the pressure of the solution before it enters the dialyser, a pump for pumping the solution through the circuit, a a haemoglobin detector at the outlet from the pump, and a steriliserforthe solution situated downstream of or in the container, the steriliser including at least two electrodes connected to a source supplying thereto electric current the frequency and amplitude of which are variable in time, the device further comprising an electronic unit for actuating an alarm unit.

2. A device according to Claim 1 wherein the dialyzing solution circuit passes through a heat exchanger connected to a source of waste heat of a transport means.

3. A device according to Claim 1 or 2 wherein the alarm unit actuates an acoustic and/or visual alarm.

4. A device according to any one of the preceding claims wherein the alarm unit actuates a source of electric pulses with electrodes connected to the patient's body.

5. A device for haemodialysis constructed, arranged and adapted to operate substantially as herein described with reference to, and as shown in, the accompanying drawing.