FR2513884A1 - EXTRA-BODY BLOOD TREATMENT APPARATUS - Google Patents

Abstract

THE INVENTION RELATES TO AN APPARATUS FOR EXTRA-BODY BLOOD TREATMENT, IN PARTICULAR HEMODIALYSIS. IT RELATES TO AN APPARATUS IN WHICH CIRCULATION TUBES WHICH MAY BE CONTAMINATED BY GERMS FROM THE PATIENT ARE MOUNTED IN CASSETTES. THE CASSETTES ARE INDIVIDUALIZED AND AUTOMATICALLY CONNECTED TO THE DEVICE BY SIMPLE PLUGGING. THEY CAN BE EASILY STERILIZED EITHER ON THE APPLIANCE OR OUTSIDE IT. APPLICATION TO HEMODIALYSIS EQUIPMENT.

Description

The present invention relates to the treatment of blood for healing

or patient care

  with blood problems and more specifically with

  reils performing such treatment outside the body.

  The treatment of blood outside the body is well known. An important example of such

  The apparatus used for this treatment is the artificial kidneys.

  in which the blood of a patient is directed

  in a set that performs filtration and purification

  The machines currently in use have serious drawbacks. For example, their appearance is frightening. The tubes come out of the machine in all the cases.

  sense, some carrying blood and other

saline conditions.

  Current machines are not only scary in appearance but also potentially dangerous

  when using them Diseases such as hepatitis

  These devices can be easily propagated through the use of these machines. Therefore, before connecting patients to these machines, they must be completely purified and sterilized so that dangerous germs can not spread for this purpose. tubes that

  blood and saline are all removed.

  cleaned and discarded and clean or new tubes are connected to the machine The purification operation is time consuming and requires a lot of effort, and

  must be performed by reliable personnel.

  A further disadvantage of the current machines is that, very often, before purification, the machines must be reconnected to the purified tubes or to a new tube This new connection is made

  in a place where serious mistakes are possible.

  For example, if a tube is connected incorrectly

  mored from one point to another, the damage can be very important or can be at least a frightening experience for the patient since the machine

  is started, the blood begins to circulate and the

  China automatically shuts down and controls devices

  which are normally both visual and acoustic

  ticks. In addition to the tubes, parts of the machine are reused constantly, for example the equipment

  pumping system intended to circulate blood and

  It is obviously preferable that these devices are new to each patient. Obviously, the treatment becomes excessively expensive. Consequently, it is necessary to properly clean these devices. before re-use The need for manual cleaning of this equipment increases the time spent on machine preparation and therefore increases

  the burden of using these machines.

  Thus, it has long been realized that an apparatus for extracorporeal blood treatment in which all the parts that are in contact with blood

  or a solution are either attributed to a patient de-

  finished and / or a type to discard after use, is very desirable, without the device is very complicated or without its cost is excessively high It has also been realized that such devices in which the connections of the device and the patient on the one hand and the different parts of the device on the other hand, are formed by tubes in a way that prevents any awesome and frightening situation of the users

  actual or potential of the machine, are very desirable.

  In addition, it has long been realized that such an apparatus in which the connections of

  blood, saline or dialysate may be

  performed with minimal risk of error, is very

desirable.

  The invention therefore relates to an apparatus for treating

  extracorporeal blood supply in which the inconveniences

  those mentioned above are substantially reduced or eliminated,

  and which has the advantageous features indicated.

  More specifically, the invention relates to a

  apparatus for extracorporeal blood treatment which

  carries a machine having a blood treatment device, tubes which can be removed from the machine and which are intended to connect the circulatory blood system of patients to the treatment device, the tubes comprising sections placed in a cassette, and a device coupling the cassette to the machine and automatic connections in this way tubes

  in suitable locations so that it

  tioning of the blood treatment device.

  The invention also relates to the assignment of cassettes to particular patients, for example by using a magnetic, electrical, optical coding

or mechanical cassettes.

  The invention also relates to cassettes

  dividualized for the circulation of solutions such as a dialysate often used in the blood treatment, so that the amount of tubes outside the cassettes is minimal, the outer tube can be discarded and replaced by a new tube for each patient or for each use of the machine and

  the device, inexpensively.

  According to the invention, the cassettes are made

  in such a way that they allow easy and simple removal of the tube sections in the cassette after each use, the used sections being discarded and the rigid casing of the cassette, possibly after purification, receiving a new set of tubes. applies to both disposable cassettes and individualized cassettes

  to particular patients, and it has the advantage of

  put the economy of the cost of the casing of the cassette.

  The invention also relates to a cassette of

  designed to cooperate with a pumping device so that pumping is achieved through the tubes of the cassette so that individual parts of a pump do not require sterilization before use

with each patient.

  The invention also relates to flowmeter devices in which the actual measurement is made outside the cassette tube so that

  sterilization processes and the risks of

are minimal.

  The invention also relates to novel measuring devices according to which body fluids or treatment solutions are held within the elements of the cassette, so that the sterilization

  can be complete and the risks of minimal errors.

  Other features and benefits of

  invention will be better understood by reading the

  following description of embodiments and with reference to the accompanying drawings in which Figure 1 is a perspective of an apparatus used in the form of an artificial kidney, in which are used a blood circulation tube cassette and dialysate cassettes; Figure 2 is a block diagram of a circuit used in hemodialysis; FIG. 3 is a plan view of an example of a blood circulation cassette, FIG. 4 is a plan view of an example.

dialysate cassette; -

  Fig. 5 is a partial sectional view showing a pressure measuring apparatus placed in the tube of a blood cassette; Figure 6 is a section of a manual clamping device shown in the open position; and FIGS. 7A and 7B show in elevation and with parts torn off for FIG. 7B, slots for passage of the pump, in the loading positions.

  and operating respectively.

  The apparatus 11 for extracorporeal blood treatment shown in FIG. 1 comprises a machine

  11 having an automatic control device that

  carries an input and read apparatus 13, shown with a cathode ray tube 14 and an instruction insertion keyboard 16. The basic machine is represented in the form of a dialyzer or

dialysis 17.

  The block diagram in Figure 2

  schematically shows the contents of the blood circuit cassette 18 and the dialysate cassette 19 The filter 17 is arranged between the cassettes, in the part between the dashed lines. Some other parts of the machine are not represented as such.

  that a bubble trap, a heater and other

  very elements that are well known to those skilled in the art.

  The organization chart starts from the device 27 of

  coupling, and it comprises a chamber 29 of an arterial pressure transducer placed in the cassette and which gives, on an external measuring device, a reading of the arterial pressure Thus, the transducer chamber

  the external measuring equipment is attached to the case.

  sette. A clamp 31 is placed near the beginning of the tube 28 This clamp can be of any suitable type but, in an advantageous embodiment, it is ordered

  automatically by the logic circuit of the machine.

  The clamp operates under certain emergency conditions and-it then closes the tube Thus, when the cassette -is fixed to the machine, the clamp 31 is open and ready to be closed When an emergency condition appears, requiring the stopping the operation of the machine, the

clip closes.

  A device is intended to add a solution

  More specifically, a tube 32 is connected to a pump 33 which is connected in series with an inlet fitting 34 to which a saline solution container is attached. The connection of the tubes 28 and 32 is connected at 36 to a main pump 37 of blood This is described

  quickly in the remainder of this memo.

  At the end of the blood pump, an anti-

  coagulant, eg heparin, is mixed with the blood and the anti-coagulant channel is indicated by reference 38. An anticoagulant pump 39 is connected by the tube

  42 and the T-connector 41 to the blood pump 37.

  The filter 17 is connected to the tee 41 by a tube 43. The filter is of a type available in

  commerce and which is closed in case of depression.

  The output of the filter 17 is connected to the cassette

  18 by a tube 44 and an inlet connector 46 of the cassette.

  The inlet 46 is attached to the tube 47 inside the case.

  The tube reaches a chamber 48 of drop-off

  This is attached to a tube 53 for removing air from the chamber by a pump 52, a tube 51 and a

  channel 49 so that the desired level of liquid is

  held in the chamber The pressure in the chamber 48 is

indicated by a manometer 57.

  A blood level detector 58 is associated with the chamber Any type of detector can be used

for this purpose.

  A flowmeter 59 coupled by a tube 61 to

  detector 58 is placed at the exit of the drop chamber

  In an advantageous embodiment, the flow rate

  meter is of a type that does not require the placing of any

  In this way, the

  Sterility preservation of the machine is facilitated.

  A detector 64 is intended to detect the

  bubbles that can form in the drop chamber-

  Automatic pliers, represented in form

  venous forceps 62, is placed close to the ex-

  This end joins the outlet connector 63 which connects to the tube 26 which joins a needle placed in a vein of the patient or any other device allowing the connection to the system.

venous patient.

  The diagram of FIG. 2 also shows the part of the circuit that is in the dialysate cartridge 19. A dialysate supply 66 is connected by various devices such as heating devices.

  measuring instrument with general reference 67, to the

  button, at a connector 68 Variable throttling

  ble 70 is mounted right after and he settles the depression

  After the strangulation 70, a device

  pressure, and this is for example a transduc-

  and a pressure gauge 69 indicating the pressure of the dialysate.

  The pressure gauge 69 is connected to a T-connector 71 extending from the tube 72 and joining tubes 73 and 74.

  joined a dialysat input clamp 76, controlled automatically

  In addition, downstream of the clamp 76, it is connected to the filter 17 via a connector 77.

and a tube 78.

  The output of the filter 17 is connected to a tube 79 and a connector 81. A tube 82 extending from the connector 81 and placed in the cassette passes into an arrangement 83.

  This one can be of a well known type.

  However, it is preferably an ultrasonic flowmeter

  sound A tube 74 is mounted in shunt with respect to the filter and it comprises a device for closing the bypass, for example a clamp 97 The tube 74 is connected to the tubes 87 and 84 by a connection 98 The output of the arrangement 83 of Control is connected by a tube 87 to a dialysate suction pump 88. The fluid from this pump is transmitted through a tube 89 and a blood leak detector indicating that the membrane placed in the filter 17 has not been removed. The output of the detector 91 is connected by a tube 92, a check valve 93 and a tube 93 to a purge as indicated by

reference 96.

  Every three minutes, for example,

  china goes into bypass mode by opening the bypass clamp 97 and closing the input and output clamps 76 and 86 so that the ultrafiltration rate

  This measurement of the rate is done by sampling

  It should be noted that the depression exerted on

  the filter is maintained by the control arrangement 83.

  This measurement with sampling is the input signal of the computer that calculates the depression and adjusts the throttling device so that the depressed

  necessary to maintain the desired level of ultrafiltration

be obtained.

  Cassettes 18 and 19 include most of the tubes that in the facility are assigned to a particular patient. The rest of the tubes and devices are associated with items such as

  heating of the filter and mixing devices

  centred which can be cleaned in a minimal amount of time and sterilized in the machine by performing certain sterilization procedures without a large number of tubes being replaced and / or sterilized, and without the tubes then being properly connected to the machine All tubes that are not placed in

  cassette do not come into contact with the

  guins extracted from the patient and therefore require only one

less severe sterilization.

  The blood cassette is represented in general form by the reference numeral 18 in FIG. 3. In an advantageous embodiment, this cassette 18 is a plastic element similar in many respects to the cassettes used in the tape drives.

  In a preferred embodiment, it

  carries two mounting holes 99 and 101 placed at diametrically opposite corners of the cassette. Plots (not shown) are obviously placed on the machine on which the cassettes are mounted, the cassettes being placed so that the studs penetrate the holes 99 and 101 The cassette is then pressed down

  until it is juxtaposed with the machine.

  it controls some switches {not shown)

  when in position The closure of

  allows the operation of pumps, pliers

  automatic sensors and some sensors so that they function

  When the power switch is turned off when the power switch is turned on, the cassette is locked in place.

  real tubes A characteristic of the cassette is

  staggered by the openings and slots allowing its

  operation with other devices such as

  these, the pumps and the sensors of the machine

  It comprises slits, for example a slot 31A through which the patient's blood is initially introduced into the apparatus. This slot 31A is made to allow the passage of a clamp mounted on the machine and having an electronic magnet or a pneumatic actuating member intended to ensure the automatic mechanical operation of the clamping surfaces Similarly, openings 33 A, 37 A, 39 A and 52 A are intended for the passage of tubes so that the tube is in contact with rotating rollers of a pump and stators fixed to the machine The rotary pumps used have movable stators which are automatically controlled following the operation of the aforementioned switches Pumps

  of this type are intended both to ensure the safe

  forced fluid supply and acting as a shutter

  allowing the circulation of the fluid or preventing it.

  Pumps are represented in the circuit

  saline solution, in the anti-solution circuit

  It should be noted that these solutions can also be added by gravity feed using controlled valves. However, in an advantageous embodiment, the volumes of the solutions are

adjusted using pumps.

  Pressure gauges and transducers

  are shown in more detail in Figure 5.

  pressure drivers, for example the associated chamber 29

  to the tube 28 are made so that they ensure a conta-

  Minimal flow of fluids flowing through the tubes

of the cassette.

  The cassette 18 is shown with two

  Arrangements 29 and 57 defining chambers for pressure transducers These two arrangements are made in the manner shown in the figure. This shows the arrangement 29 which comprises a soft and narrow tube such as a tube 106 through example A cylinder section joins a tube 107 which is separated by a diaphragm 108 above it, a liquid 109 is kept when the pressure in the tube 106 varies, the pressure of the tube 109 also varies so that the reading

  given by the manometer 111 varies.

  An orifice 103 formed in the cassette is

  also intended for the passage of an accumulator 30

  it is made of an elastic material that leaves a

  tain space for the circulation of the fluid transmitted to the pump 37 by the connection 36 T The accumulator ensures

  the transmission of a constant flow by the pump It sup-

  The voltage peaks created by the pump rollers are also added. The accumulator is also a storage volume in the operating mode with a single needle. Orifices 113, 114 are also formed in

  the cassette for access to the chamber 48 of gout-à-

  drop These holes allow the passage of instruments

  detection of the liquid level in this chamber.

  Similarly, an orifice 59 A is shown below this

  chamber for the passage of the blood flow meter and the detection

bubble.

  The section of FIG. 6 gives an idea of the thickness of the cassette and shows how the tube is

  is housed in the plastic cassette.

  Figure 6 is the one from an orifice

  116 used for the introduction of pharmaceutical substances

  ticks and the like in blood undergoing treatment.

  The orifice 116 opens into the tube 117 which is

  The tube 117 joins directly

  The forceps 118 are shown in FIG.

  a hand-held forceps with a section 119 of

  chage for accommodating and retaining the elastic lever 121 while the clamping points 122 and 123 exert sufficient pressure on the tube 117 so that it is closed The orifices such as 116, 126, 127 and 128 are intended to accommodate bacterial filters mounted in

series with the tube.

  The cartridge also has a device for identifying

  encoding cation represented by the device 129 in general The identification is carried out in this

  case by a series of magnetic surfaces of the type well con-

  The patient has a card that also has holes corresponding to

  The card is placed in a slot formed in the machine. If the codes correspond, the machine can function. The code assigned may be of various forms well known to those skilled in the art and they are not

  not necessarily magnetic type.

  The dialysate cassette 19 is shown more precisely in FIG. 4 Mounting holes

  such as 136, 137 are also represented at corners dia-

  The cassette 19 also has slots and openings. An opening 88 A is provided for the passage of the dialysate pump.

  placed near the entrance and exit tube.

  Input clamping flange 76a for the passage of the gripper 76 The variable constriction 70 of the block diagram is located in the aperture 70A. The aperture 97A is for the passage of the bypass clip 97 The opening 86 A is for the passage

  output clamp 86 An opening 91 A is also des-

  at the passage of the blood leak detector 91

  check valve 93 is connected on the right to the

  and an enlarged slot 93 A formed in the cassette

  is intended to house the valve 93.

  The cassette 19 contains a device for

  the flow rate of extraction of water from the filter

  already many measurements of the water extraction rate.

  All these measurements can be used in the context of the invention However, in one embodiment

  advantageous, the measuring device comprises a trans-

  ultrasonic transducer The device for controlling this water extraction flow rate is represented on the block diagram of FIG. 3 and a cavity 83 A is associated with it for the housing of an ultrasonic transducer incorporated in the machine. A manual clamp 80 is also intended to act on a tube 90 extending from a T-fitting 82 and joining an orifice 85. An opening 80 A formed in the cassette is intended for the passage of the clamp 80. An opening 91 A allows the housing of the set 91 of detection of

leaking blood.

  The references of the tubes of FIGS.

  4 are the same as the tubes of the synoptic diagram.

  they are not repeated for the sake of clarity and

brevity.

  The transducer 69 of the dialysate pressure

  operates in a manner already described.

  So, just like the blood cassette, the

  dialysate cassette is relatively small and

  combrante, convenient cleaning, and it includes a

  positive such as an attributive code 139 indicating which individual patient matches the cassette The connectors 68, 77 and 81 facilitate the use of the cassette by

  automatic connection of the tubes to the machine.

  The pump 37 is shown in FIGS. 7A and 7B, in cooperation with the cassette 18, so that

  the advantageous characteristics of this one appear-

  The pump has a rotor 141 Biel-

  142, 143 and 144 carry several rollers 146, 147 and 148 and are themselves mounted on the rotor. The rollers travel in a cylindrical position when the rotor rotates.

around its axis 149.

  The stator 151 is movable between a position

  loading (Figure 7 A) and a position of

  In the loading position, the stator is remote from the place traversed by the rollers so that, when the cassette is mounted on the machine, the tube 152 can be easily and automatically housed.

between the rotor and the stator.

  In the operating position, the place described by the rollers comes against the tube 152 which undergoes

  thus the desired pumping The stator is moved by rotating

  A device 15, such as slots 156, 157 cooperating with lugs 158, 159 which pass into these slots and protrude from

  machine, ensure the linearity of the displacement of the stator.

  Thus, when the cassette is placed on the machine, its tube is housed between the stator and the rotor. Pushing the cassette into position controls an electromagnet (not shown) which rotates the cam 153 so that

  the stator returns to the operating position.

  During operation, the patient is prepared

* re and the machine is placed near the patient, then the cassettes are placed in the machine The coding is checked so that the correspondence between the cassette and the patient is checked Needles are then

  placed in the patient's arm and the machine is com-

  moved by moving a start-up switch.

  Clamps and pumps work by taking the patient's blood and placing it in the filter so that noxious material is extracted.

  in a known manner for automatic artificial kidneys

  In addition, the arrangement of cassettes on the

  machine not only allows automatic operation

  clamps but also ensures the positioning and control of the pumps which can then function properly The pumps are controlled according to a program introduced into the memories of the machine using the keyboard and cathode ray tube as

shown in Figure 1.

  One of the advantages of cassettes is to

  safer use of dialysis machines

  at home Thanks to the cassettes, the proper connection

  In this respect, it should be noted that although a relatively large machine has been shown in the drawings, less bulky machines, including the apparatus described herein, may be used in the home. of the

patients.

  Another advantage of cassettes is that they can be easily washed and sterilized while they are still on the machines.

  the machine has been disconnected from the patient, it is connected

  rope so that it is rinsed with the help of

  machine, the flushing fluid flowing in the cassettes Then a sterilization solution is pumped into the cassettes These can be

  preserved between uses, with the sterile fluid

the user they contain.

  Of course, various modifications may be made by those skilled in the art to the devices which have just been described solely as examples.

  non-limiting without departing from the scope of the invention.

Claims (13)

  An apparatus for extracorporeal blood treatment, characterized in that it comprises:   machine (12) having a processing device   blood (17), tubes that can be removed from the   machine and intended to connect the cardiovascular system   the patient to the treatment device, and the tubes comprise tube sections placed in a cassette (18).   2 Apparatus according to claim 1, characterized   in that it includes individual coding devices   (129), the tubes are arranged in individual cassettes (18), and these contain essential parts of the tubes.   Apparatus according to claim 1, characterized in that the treatment device is a device   filter (17) for hemodialysis.   4 Apparatus according to claim 3, characterized in that it comprises, in addition to a blood cassette   (18), a dialysate cassette <19).   Apparatus according to any one of the preceding claims, characterized in that a pump (37) acts on the tubes placed in the cassettes and ensures   forced circulation of blood and dialysate.   6 Apparatus according to claim 5, characterized in that it comprises flowmeters (59) cooperating with cassettes.   Apparatus according to claim 6, characterized in that it comprises a device for measuring a liquid level (58) intended to work with the cassette so that it measures the level of the liquid in a chamber drip.   Apparatus according to claim 1, characterized in that the cassette (18) has slots (31A, 33A, 37A,   39 A, 52 A) intended for the passage of devices of the   china so that these can act on the tubes of The tape.   Apparatus according to claim 8, characterized   rised in that the devices comprise a pump   <37) for circulating fluid in the tubes.   Apparatus according to claim 9, characterized   in that the fluid is a saline solution.   Apparatus according to claim 9, characterized   characterized in that the pump comprises a rotor (141) and a stator (151), the latter having a remote loading position of the rotor, so that the tube (152) can be placed automatically between the rotor and the stator, and a working position in which the rotor compresses the tube against the stator and ensures pumping when it rotates. Apparatus according to claim 9, characterized   in that it comprises a device for measuring the quantity water withdrawn from the patient.   Apparatus according to claim 12, characterized   in that the measuring device (97) comprises a device for circulating the flow of   dialysate in connection with the filter device   a device (70) intended to maintain a   pressure on the dialysate part of the filter device   tion, and a dialysate pump coupled with a   flow control system (83) between the   lysate of the filtration device and a purge.   Apparatus according to claim 9, characterized in that it comprises a device for transmitting   successively a rinsing fluid and a sterile fluid.   machine so that these fluids circulate   in the cassettes (18, 19) under the control of the pumps.