JPS61143068A - Blood dialytic method and apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a method and apparatus for performing hemodialysis using a dialyzer, and is used to increase dialysis efficiency and shorten the time required for dialysis. .

(Prior art) Hemodialysis, which is performed using an artificial kidney device (dialysis device), purifies the blood by eliminating waste products from the body or taking in what is needed in place of the kidneys when the human body suffers from renal failure. It is widely used to carry out.

FIG. 10 shows an example of a conventional dialysis device, which uses a positive pressure method. In Fig. 10, cannulae la and lb are punctured into blood vessels in the extremities of body A to serve as entrances and exits for extracorporeal circulation of blood. The blood pump 2 supplies a constant flow of blood flowing out from the cannula 1a to the dialyzer 3, and the constrictor 4 supplies the blood to the tube 5.
A stenosis is created in the dialyzer 3 to generate positive pressure in the blood inside the dialyzer 3.

At the blood inlet and outlet of the dialyzer 3, an air chamber 6a,
6b and pressure gauges 7a and 7b are provided as a guide to know the ultrafiltration pressure. A supply path 8a and a discharge path 8b are connected to the dialyzer 3, and a separately prepared dialysate is supplied thereto. To perform hemodialysis with this conventional dialysis device, the supply path 8
While continuously supplying dialysate while rotating the blood pump 2, the diaphragm 4 is throttled to generate positive pressure, and the pressure gauges 7a and 7b are checked to ensure an appropriate ultrafiltration pressure. Adjust.

By the way, the phenomena that occur inside the dialyzer during hemodialysis are the movement of substances and water due to osmotic pressure and the movement of water due to ultrafiltration.If water is also considered a substance, this movement of substances It is known that there is the following relationship. According to this, the rate of mass transfer is proportional to the concentration gradient and inversely proportional to the resistance. In addition to the resistance of the dialysis membrane itself, the resistance includes resistance due to the fluid film that exists along the dialysis membrane. FIG. 11 is a diagram for explaining the concentration gradient inside and outside the dialysis membrane and the fluid boundary film. Let the concentrations of a certain substance in the blood and dialysate be cB and CD, respectively, and the overall mass transfer coefficient be K. The moving speed NA of a substance per unit area of a film can be expressed as NA = K (Co - Co ). Further, when the membrane transfer coefficients of the substance on the blood side and the dialysate side are respectively KB and KO, the diffusion coefficient of the substance in the dialysis membrane is DH, and the membrane thickness is L, then K KB DHKo .

It is known that the total resistance 1/ is equal to the sum of the resistances of the blood-side membrane, dialysis membrane, and dialysate-side membrane (Artificial Dialysis Research Society, Vol. 2, No. 2, p. 9, 1969).
8 onwards).

Therefore, in order to increase dialysis efficiency using the same dialyzer, the flow rate of blood and dialysate should be increased to generate turbulence on the surface of the dialysis membrane and reduce membrane resistance. Regarding this only on the blood side, dialysis efficiency will increase if the blood flow rate is made as fast as possible, but there is a limit to the flow rate of blood that can be circulated extracorporeally from body A, approximately 15%.
0 to 20011 Il/min. Therefore, in the conventional dialysis method, blood is taken out as much as possible within a limit and continuously passed through the blood, and the dialysis efficiency in this respect has not been high.

(Object of the Invention) The present invention was made in view of the above-mentioned circumstances, and aims to improve dialysis efficiency and shorten the time required for dialysis.

(Technical Means of the Invention) The method of the present invention is a method of performing hemodialysis using a dialyzer, in which a portion of blood is stored on the upstream side of the dialyzer in a blood circuit, and the stored blood is relatively This hemodialysis method is characterized in that the blood is discharged at a high flow rate and supplied to the dialyzer, and this process is repeated. The device of the present invention also includes a blood tank provided upstream of the blood circuit of the dialyzer to store blood and capable of applying positive pressure to the stored blood, and a blood tank provided downstream of the blood tank. an on-off valve provided to control the flow of blood; a detector for detecting that a certain amount of blood has accumulated in the blood tank; and a control to open the on-off valve based on a detection signal from the detector. This is a hemodialysis apparatus characterized by having a control device that performs the following steps.

(Example) Hereinafter, the present invention will be described by way of an example with reference to the drawings.

FIG. 1 shows an embodiment of the dialysis apparatus of the present invention in a positive pressure method. In the same figure, la and lb are canyule,
2 is a blood pump, 3 is a dialyzer, 5 is a tube, 8a,
8b is a dialysate supply or discharge path, 10 is a pressure measuring device, 11 is a storage device, 12 is a blood flow control device, 13 is a filter device, and 14 is an electric control device for controlling these.

In addition to these, an infusion needle and a heparin injector are connected to the blood circuit of the dialysis machine, but these are not shown.

Referring also to FIGS. 2 and 3, the pressure measuring device 10 measures the pressure of blood on the upstream side of the blood pump 2 without contacting with air, and includes a capsule-shaped pressure transducer 15. , a pressure sensor 16 and a syringe 1 connected thereto.
It consists of 7. The pressure transducer 15 has a sealed container 18 whose interior is divided into two chambers, a blood chamber a and an air chamber, by a diaphragm 19. An outlet 20b and two connection ports 20c and 20d communicating with the air chamber are provided. A tube 5 is provided at the inlet 20a and the outlet 20b.
a and 5b are connected so that blood flows in the blood chamber a, the connection port 20c is connected to the pressure detector 16 by a tube 16a, the connection port 20d is connected to the syringe 17 by a tube 17a, and the air chamber The amount of air in the chamber is increased or decreased by pumping the syringe 17 to adjust the amount of deformation of the diaphragm 19, and its pressure is measured by the pressure sensor S16. A clamp 21 for clamping and closing the tube 17a is attached to the tube 17a, and this clamp 21 is removed when the syringe 17 is operated.

The pressure sensor 16 has the same function as the pressure sensor described in Japanese Unexamined Patent Publication No. 59-181162, which was previously proposed by the inventor of the present invention, and for details, please refer to the same publication. Here I will explain the outline.

While the blood pump 2 is operating and normal dialysis is being performed, the blood in the blood chamber a remains at a nearly constant negative pressure.
If excessive water removal is performed, the negative pressure will become even larger, and if the tip of the cannula LA sticks to the inner wall of the blood vessel and the blood is occluded, the negative pressure will become even larger. The pressure can be set so as to detect these negative pressures in two stages and output a signal, and the pressure can also be read visually. That is, container 1
Reference numeral 8 indicates two container members 18a each having the same shape and cut in half.
, 18a facing each other, the container member 18a
, 18a, a diaphragm 19 having the same outer periphery is sandwiched between each of the collar portions 18b, 18b, and these are welded together and brought into close contact with each other. The container member 18a is integrally molded using a polymeric material such as vinyl chloride, hard vinyl chloride, polycarbonate, or silicone rubber. The diaphragm 19 has appropriate elasticity and is made of the same material as the container member 18a to facilitate welding.

It is convenient to make the container member 18a or the diaphragm 19 transparent so that the internal state can be monitored.

The storage device 11 includes a blood tank 22 that can store blood and apply pressure to the blood, a pressure sensor 23 and a syringe 24 connected to the blood tank 22 . The blood tank 22 has the same structure as the pressure transducer 15 described above, and its shape is large enough to store the required amount of blood. That is, in FIG. 4, the inside of the container 18 is divided into a blood chamber a and an air chamber by a diaphragm 19, and blood flows into the blood chamber a from the tube 5c and is stored there, as well as being connected to the blood circuit. If a flow path is formed behind the tube 5d, the blood in the blood chamber a will flow out from the tube 5d. The blood in the blood chamber a is pressurized by the air pressure by increasing or decreasing the amount of air in the air chamber a by pumping the syringe 24, and the pressure in the air chamber a is detected by the pressure detector 23, This measures the amount of blood that has been collected. The pressure sensor 23 can be the same as the pressure sensor 16 described above, but it needs to be able to detect positive pressure in a wider range. And pressure sensor 2
3 outputs signals when the amount of blood stored in the blood chamber a of the blood tank 22 is above a certain amount or below a certain amount. Naori lamp 2
5 is similar to the clamp 21 described above.

Referring also to FIG. 5, the blood control device 12 includes a pressure transducer 26, a pressure detector 27 and a syringe 28 connected thereto, and a bypass section 29 that bypasses blood without passing through the pressure transducer 26. It consists of. The pressure transducer 26 is
One of the container members of the pressure transducer 15 described above has a flat plate shape, that is, the container 30 is composed of a flat container member 30a and a curved container member 30b, and the diaphragm 19 is approximately in a free state. It extends along the inner surface of the container member 30a. Connection port 31 through which blood flows in or out
A bypass passage 32 and a bypass valve 33 are provided between a and 31b.
A bypass section 29 is provided, and the bypass passage 32 is opened or closed by opening and closing the bypass valve 33. This bypass valve 33 is electromagnetically operated, and may have a structure in which, for example, the bypass passage 32 made of a flexible tube is pinched and compressed from the outside by the operation of a treid. If an appropriate amount of air is fed into the air chamber of the pressure transducer 26 to maintain a constant pressure, blood from the tube 5e will flow into the blood chamber a from the connection port 31a unless the pressure becomes higher than that pressure. I can't. Therefore, when the bypass valve 33 is closed, when blood is flowing, a constant pressure will be generated regardless of the flow rate, so it cannot be used as a positive pressure generator in the normal positive pressure method. In addition, in this embodiment, as will be clear from the explanation of its function later, it can be used as a safety valve that allows blood to flow when the pressure exceeds a certain level.

The filter device 13 is for removing air and foreign matter such as small blood clots that may be mixed into the blood. Its structure is shown in FIG. 6, and the filter container 34 is connected to the pressure transducer 15 described above. It is the same as the container 18 shown in Figure 1, except that only the diaphragm 19 is replaced with a suitable mesh filter element 37. Connection ports 38a located in opposite positions
, 38d are connected with tubes 5f, 5g so that blood flows through the filter element 37, and tubes 35 are connected to the other connection ports 38b, 38C.
A syringe 35.36 is connected via a1368, and these tubes 35a, 36a are connected to a clamp 39.40.
is clamped.

Therefore, blood that flows into the filter container 34 from the connection port 38a is filtered by the filter element 37 and flows out from the connection port 38d, but if air is mixed in the blood, an air pocket 41 is formed above. , so that air may accumulate from time to time through the connection port 38c using the syringe 36. Further, foreign substances such as small blood clots whose passage is blocked by the filter element 37 may be taken out from the connection port 38b using the syringe 35. The filter 37 may be placed in such a position that the connection port 38d is not directed upward.

Although not shown, the dialysate supply path 8a and discharge path 8b of the dialysis machine 3 are connected to piping lines and valves for supplying and discharging the dialysate, a lightweight device for measuring the amount of water removed, etc. has been done. The method of supplying the dialysate is approximately 500 mm into the dialyzer 3.
ojt/min continuously, or by pressurizing an amount of dialysate approximately equal to the priming amount of dialysate in the dialyzer 3 to several tenths of kg/aJ to 1 kg/co1 at a high flow rate for short periods of time. There are methods such as passing only time and doing this intermittently. For details regarding the latter method, refer to the specification of Japanese Patent Application No. 58-212895, which was previously proposed by the inventor of the present invention.

The electric control device 14 controls the dialysis machine,
It consists of hard logic of relays and semiconductors, soft logic using a microcomputer, or a combination of these, and opens or closes the bypass valve 33 in response to the upper or lower pressure limit signal from the pressure sensor 23, and also opens or closes the bypass valve 33 and closes the bypass valve 33. The blood pump 2 is stopped by the lower limit signal of the pressure (negative pressure) from the dialyzer, or the dialysate supply is also stopped and an alarm is issued. Become.

First, in the preparation stage, physiological saline is sufficiently distributed in the blood circuit connected by the tube 5, and
Air is sufficiently removed from the blood circuit by using the air removal device of each device or by shaking each device, and then blood is introduced.

Next, the detected pressure of the pressure detector 16 of the pressure measuring device 10 is set. To do this, the resting shunt pressure Pl is measured by the pressure detector 16 while the blood pump 2 is stopped. Pl is a positive pressure and is usually several tens of an+)Ig.

Next, the blood pump 2 is rotated, and at this time the pressure sensor 1
6, the shunt pressure P2 during circulation is measured. P2 is
This is the value obtained by subtracting the pressure drop due to the cannula 1a from Pl, and is usually a negative pressure.

The first set pressure ps of the pressure detector 16 is set to the value p2-p, and the second set pressure P4 is set to Pa-(50 to 10o). Therefore, Pa has a value lower than the shunt pressure P2 during circulation by the shunt pressure P during rest, and P4 has a value lower than Pa by 50 to 100 mmHg. At this time, the amount of air in the air chamber is adjusted using the syringe 17 so that the amount of deformation of the diaphragm 19 is as small as possible.

Next, the pressure in the air chamber of the pressure transducer 26 of the blood flow control device 12 is set appropriately high so that blood flows through the pressure transducer 26 under normal conditions.

The syringe 2 is placed inside the air chamber of the blood tank 22 of the storage device 11.
4, air is sent in and adjusted while watching the pressure sensor 23 so that the preload pressure is above a certain level when no blood is stored in the blood tank 22.

This preload force is provided so that when blood is discharged from the blood tank 22, the blood flows at a sufficient flow rate against the circuit resistance of the dialyzer 3 and downstream thereof.

When the bypass valve 33 is closed, blood begins to accumulate in the blood tank 22, which increases the pressure in the air chamber of the blood tank 22. When a certain amount of blood accumulates in the blood tank 22, the pressure detector 23 Set so that the pressure upper limit signal is output. By this signal, the bypass valve 3
3 opens, the stored blood is released under pressure in a short time and flows into the dialyzer 3 at a high flow rate, destroying the membrane on the blood side of the dialyzer 3 and lowering the membrane resistance. It will be necessary to do so.

When most of the blood in the blood tank 22 has been discharged,
The pressure sensor 23 is set to output a signal indicating the lower limit of the pressure, and this signal closes the bypass valve 33 and blood begins to accumulate in the blood tank 22 again. During this period, the blood in the dialyzer 3 is pressurized by the pressure from the blood tank 22, and dialysis is performed by the movement of substances and water within the dialyzer 3. The amount of blood stored in the blood tank 22 may be set to be the same amount or half the priming amount of blood in the dialyzer 3, for example, 80 to 100 Il+j! And it is sufficient. There is no problem even if this amount of blood flows into the body in a short period of time. Therefore, normally, the amount of blood that can flow out from the body is 150 to 150 b, and the accumulation and discharge are repeated 2 to 3 times per minute. Compared to the conventional case where blood is continuously passed, the dialysis efficiency according to the above embodiment is 20 to 2.
Improved by 5%. Although the blood pump 2 continues to operate while blood is being discharged from the blood tank 22, it may be stopped during this period. In addition, if dialysate is also supplied intermittently, the relationship between the tamping of dialysate supply and the timing of blood discharge should be done at the same time or with a certain time lag between them. It is conceivable to do this in conjunction with each other, or to do it independently of each other. For example, when the pressure detector 16 outputs a detection signal, the blood pump 2 may be stopped and the blood in the blood tank 22 may be discharged.

In the above-mentioned embodiment, in addition to the effect of improving dialysis efficiency compared to conventional methods, the blood circuit is a closed circuit and there is almost no contact between blood and air, so blood coagulation is less likely to occur. It has an excellent effect, and as a result, the amount of anticoagulants such as heparin used is significantly reduced, and there is an advantage that a relatively large amount of blood can be stored in the blood tank 22 for a long time. . Also,
The risk of bacterial infection is drastically reduced, and since the blood chamber a is filled with blood, there is no risk of the air in the air chamber getting mixed into the blood circuit such as the tube 5, which was the case in the past. The amount can be easily adjusted, and there is no possibility that blood will flow into the pressure gauge 16.23, making it unusable. Moreover, the pressure transducer 15
Also, since the blood tank 22 can be used in any position, the tube 5 can be made to the shortest length and the amount of extracorporeally circulating blood can be reduced accordingly, making it extremely convenient to handle. It has the advantage of being suitable for portable use.

FIG. 7 shows another embodiment of the dialysis apparatus of the present invention.

This is a device that is almost the same as that shown in FIG. 1 applied to the single needle dialysis method, and the blood flow path flowing out from the filter container 34 of the filter device 13 is connected to the same cannula as the inflow side tube 5a by a tube 5g. A branch connection is made to 1a. In this dialysis device, the blood pump 2 is stopped while blood is discharged from the pressure tank 22, and the tube 5
It is necessary to alternately inflow blood from tube a and outflow from tube 5g. In the conventional single-needle dialysis method, an air chamber is used as a blood tank and is connected between the dialyzer and the bypass section 29, so the amount of blood that can be stored is small and the amount of blood that needs to be added for discharge is limited. The resulting pressure is low, and it takes almost the same amount of time to draw blood out of the body and introduce it, and the flow rate inside the dialyzer 3 is not fast, so it is easier to form a membrane, which is different from conventional multi-needle dialysis. 60 compared to the method (e.g. shown in Figure 10)
However, the single needle dialysis method of this example was able to obtain the same dialysis efficiency as the dialysis method shown in Figure 1, and was ultimately superior to the conventional single needle dialysis method. In comparison, about twice the dialysis efficiency can be obtained.

FIG. 8 shows still another embodiment of the dialysis apparatus of the present invention, which uses a positive pressure method, in which the blood flow control device 12 shown in FIG. The throttle valve and the dialysate pump are connected to the supply path 8a and the discharge path 8 so that the dialysate inside the dialyzer 3 has a negative pressure.
b, respectively. The operation and effects of this dialysis apparatus are substantially the same as those explained in FIG. 1, so the explanation will be omitted.

The embodiments of the present invention are not limited to these, and for example, the pressure measuring device 10 may be omitted, or the pressure transducer 26 of the blood flow control device 12 may be omitted.

FIG. 9 shows another embodiment of the pressure transducer 15 or the blood tank 22, in which the container 42 is made up of four container members 42a of the same shape facing each other, with the diaphragm 19 in between, and each flange part. 42b are welded, and the connection port 43a,
43b, 43c, and 43d are each linear, making it easy to connect tubes and facilitate blood flow.

In each of the above embodiments, a pressure sensor 16, 23, 27 having a Bourdon tube type indicator needle and an upper and lower limit setting needle was used, but a strain gauge type or semiconductor type sensor and an appropriate setting display may also be used. It may also be a combination of devices. Syringe 2
3 may be replaced by other suitable pumps. The pressure detectors 16, 23, 27 and the syringe 23 may be connected branchingly from one connection port, in which case the other connection port is not necessary and can be plugged with a blind plug. .

(Effects) According to the present invention, dialysis efficiency is improved and the time required for dialysis is shortened. The present invention can be used in conventional positive pressure methods, positive pressure methods, single needle dialysis methods, multineedle dialysis methods, and other dialysis methods, and especially when applied to single needle dialysis methods, the dialysis efficiency is remarkable. It becomes possible to take full advantage of the excellent advantage of this method that only one cannula is required, reducing the time, labor, and expense required for dialysis, and increasing safety.

[Brief explanation of the drawing]

Fig. 1 is a diagram of a dialysis machine showing an embodiment of the present invention, Fig. 2 is a sectional view showing an enlarged pressure measuring device, Fig. 3 is a plan view of the pressure transducer shown in Fig. 2, and Fig. 4 5 is an enlarged sectional view of the storage device, FIG. 5 is an enlarged sectional view of the blood flow control device, FIG. 6 is an enlarged sectional view of the filter device, and FIG.
8 and 8 respectively show a dialysis device according to another embodiment of the present invention, FIG. 9 is a sectional view showing another embodiment of the pressure transducer and blood tank, and FIG. 10 shows a conventional dialysis device. A diagram showing an example, FIG. 11, is a diagram showing the principle of dialysis. la, lb... cannula, 2... blood pump,
3... Dialyzer, 5... Tube, 11... Storage device, 14... Electric control device (control device), 18...
Container, 19... diaphragm, 20a... inlet,
20b... Outlet, 20c, 20d... Connection port, 2
2...Blood tank, 23...Pressure detector (detector)
, 33... bypass valve (on/off valve), a... blood chamber,
b...Air chamber.

Claims (1)

[Claims] 1. A method for performing hemodialysis using a dialyzer, which comprises storing a portion of blood on the upstream side of the dialyzer in a blood circuit, and discharging the stored blood at a relatively high flow rate. A method for hemodialysis, characterized in that the blood is supplied to the dialyzer, and this process is repeated. 2. Hemodialysis according to claim 1, wherein while blood is being stored, the downstream side of the blood circuit of the dialyzer is closed and positive pressure is applied to the blood in the dialyzer. Method. 3. The hemodialysis method according to claim 1, wherein the dialysate in the dialyzer is kept under negative pressure while blood is being stored. 4. A blood tank that performs hemodialysis using a dialyzer, which is provided upstream of the blood circuit of the dialyzer and is capable of storing blood and applying positive pressure to the stored blood; an on-off valve provided downstream of the blood tank to control the flow of blood; a detector that detects that a certain amount of blood has accumulated in the blood tank; and a detection signal from the detector. A hemodialysis apparatus comprising: a control device that controls opening of the on-off valve. 5. The blood tank has a hollow sealed container and a diaphragm that divides the inside of the container into two chambers, a blood chamber and an air chamber, and the container has a chamber that communicates with the blood chamber. 5. The hemodialysis apparatus according to claim 4, further comprising an inlet and an outlet for communicating with the air chamber, and at least one connection port communicating with the air chamber.