JPS6357067B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention provides a blood circuit for a hemodialysis machine.
It relates to a device that circulates blood extracorporeally and returns it to a living body while measuring pressure and filtering it.

(Prior art) Figure 8 shows an example of a conventional dialysis device.
This is based on the positive pressure method. In Figure 8, cannulae 1a and 1b are inserted into the blood vessels of the limbs of living body A.
Puncture the hole and use it as an entrance/exit 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 creates a stenosis in the tube 5 to generate positive pressure in the blood within the dialyzer 3. An air chamber 6 is installed at the blood inlet and outlet of the dialyzer 3.
a, 6b and pressure gauges 7a, 7b are provided as a guide for knowing the ultrafiltration pressure inside the dialyzer 3. 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 using this dialysis device, while continuously supplying dialysate from the supply path 8a, the blood pump 2 is rotated, the diaphragm 4 is squeezed to generate positive pressure, and the pressure gauge 7
Check a and 7b and adjust the ultrafiltration pressure to an appropriate level.

In addition, in order to improve the dialysis efficiency of such a dialysis machine and shorten the time required for dialysis, or to automatically monitor abnormal situations during dialysis and improve safety, the inventor of the present invention has previously proposed the dialysis apparatus described in Japanese Patent Application No. 58-57147 and Japanese Patent Application No. 58-212895.

In any of these dialysis machines, an air chamber is provided to measure the blood pressure, but as shown in an enlarged view in FIG. 9, inside the air chamber 6, blood c and air d are in constant contact with. This contact acts to promote coagulation in the blood coagulation reaction system, thus speeding up coagulation. When small blood clots are formed due to coagulation, they clog dialyzers and reduce dialysis efficiency, and maintaining blood fluidity is an essential condition for hemodialysis. becomes an extremely inconvenient situation. To prevent this, anticoagulants such as heparin are usually injected, but in some patients bleeding may become unstoppable, so the minimum effective dose of heparin should be determined for each case. is extremely complicated and difficult. In addition, in order to adjust the liquid level of blood c in the air chamber 6 and the pressure of air d, a tube 9a is used.
The amount of air d is adjusted using the syringe 10 while the clamp 9 blocking the blood is loosened, but if this adjustment is incorrect, the liquid level of blood c will rise abnormally. The pressure gauges 7a and 7b may become unusable, or bacterial infection may occur in the blood.
Conversely, the liquid level may fall abnormally, causing air to be pumped into the tube 5, creating a very dangerous situation for the patient. In addition, such an air chamber 6 must be kept in a certain posture when used, and the tube 5 used for piping may become long or bent, or the pressure gauge 7a may become long or bent. , 7b and the syringe 10, which is extremely inconvenient in handling.

In order to solve these difficulties, for example, as shown in FIG. 1, a pressure measuring device is used in which the inside of a sealed container 11 is divided into a blood chamber a and an air chamber b by a diaphragm 12, and the blood flowing into the blood circuit is Room a
A device was developed in 1975 that was designed to reduce blood coagulation as much as possible by blocking blood inside the body with a diaphragm 12 and preventing it from coming into contact with air.
Although it is proposed in No. 164045, even with this conventional technology, it is impossible to completely prevent blood coagulation in the blood circuit, and blood circulation may be affected by the coagulation tendency of the blood itself and other factors. Small blood clots may form during the process.

(Problems to be Solved by the Invention) The present invention has been made in view of the above-mentioned problems, and is capable of measuring pressure without contact between blood and air in a blood circuit. This method attempts to solve the above-mentioned problems by removing the coagulated small blood clots generated in the blood circuit from the blood circuit without exposing them to air.

(Technical Means for Solving the Problems) The present invention provides a hemodialysis apparatus in which a dialyzer 3 is interposed in the middle of a blood circuit 5 for extracorporeally circulating the blood of a living body to perform hemodialysis. The inside of the sealed container 11 is divided into a blood chamber a and an air chamber b by a diaphragm 12, and a blood circuit 5 is connected near the blood entrance/exit of the blood chamber 11 so that blood flows into the blood chamber a. A measuring device 26 that detects the blood pressure in the dialyzer 3 by measuring the pressure of the air in the air chamber b is interposed, and a similarly sealed device is provided near the blood circuit 5 on the reflux side to the living body. The interior of the container 28 is divided by a filter element 29 into an inflow blood chamber 28a and an outflow blood chamber 28b, and an inflow and outflow blood circuit is located at one of the paired positions diagonally in the vertical direction with the filter element 29 in between. A pair of blood circuit connection ports 30a and 30d are connected to the upper side of the other paired position, and an air vent connection port 30c communicating with the outflow side blood chamber 28b is connected to the inflow side blood chamber 28a on the lower side. Connecting ports 30b for extracting foreign matter are provided, and a syringe 23 is connected to the connecting port 30c for removing air and the connecting port 30b for extracting foreign matter.
It is characterized by interposing a filter 27 to which the filters 23c and 23d are connected.

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

In FIG. 1, the inside of a sealed container 11 is divided into a blood chamber a and an air chamber b by a diaphragm 12.
It is divided into two rooms. The container 11 has an inlet 14 and an outlet 15 that communicate with the blood chamber a, and a first connection port 16 and a second connection port 1 that communicate with the air chamber b.
7 is provided. Inlet 14 and outlet 15
are connected in series to a required blood circuit via tubes 18 and 19, and blood flows into the blood chamber a from the inlet 14 and flows out from the outlet 15. First connection port 16 and second connection port 1
7 is connected to a pressure gauge 22 or a pump syringe 23 via tubes 20 and 21, respectively, and the tube 21 is clamped and closed by a clamp 24.

The pressure transducer 25 includes the container 11 and the diaphragm 1
2, and its more specific structure is as follows. That is, referring also to FIG. 2, the container 11 is made up of two half-split container members 11a, 11a, each having the same shape, facing each other.
A diaphragm 12 having the same outer periphery is sandwiched between the brim portions 11b, 11b of a, and these are welded to each other in close contact with each other. The container member 11a is made of a polymer material such as vinyl chloride, hard vinyl chloride, polycarbonate, or silicone rubber, and has an inlet 14, an outlet 15, a first connection port 16, and a second connection port 16.
It is integrally molded together with the connection port 17. The diaphragm 12 has appropriate elasticity and is made of the same material as the container member 11a to facilitate welding. It is convenient to make the container member 11a or the diaphragm 12 transparent so that the internal state can be monitored.

FIG. 3 shows the measuring device 26 configured as described above.
This figure shows a dialysis apparatus in which the air chamber 6a shown in FIGS. 8 and 9 is used in place of the conventional air chamber 6a. In FIG. 3, 22a and 22b are pressure gauges, 23a and 23b are syringes, 24a and 24b are clamps, 25a and 25b are pressure transducers, and 26
a and 26b are measuring devices, which are the same as those shown in FIG. Further, 27 is a filter interposed near the reflux side of the blood circuit to the living body, which will be described later. The operation of the measuring devices 26, 26a, 26b will be explained based on FIGS. 1 and 3. First, in the preparation stage, a sufficient amount of physiological saline is introduced into the blood circuit connected by the tube 5, and air is removed from the blood circuit by using the air bleed device of each device or by shaking each device. After that, blood is introduced. Therefore, with blood pump 2 stopped,
The amount of air in each air chamber b is adjusted using syringes 23a and 23b so that the pointers of each pressure gauge 22a and 22b become zero. While the blood pump 2 is rotating to perform dialysis, blood flows through each blood chamber a, and the diaphragm 12 expands toward the air chamber b due to the pressure of the blood, and the air is released by that amount. The volume of chamber b decreases, the air pressure increases, and an equilibrium state is reached. By measuring the air pressure at that time with the pressure gauge 22, the blood pressure can be determined. If the blood pressure is high, the measurement may be performed by sending air into each air chamber b using the syringes 23a and 23b to minimize the amount of deformation of the diaphragm 12.

In the dialysis apparatus of FIG. 3, the pressure transducer 25
Since there is no contact between blood and air within the chambers a and 25b, blood coagulation is not accelerated unlike in conventional air chambers, and the amount of heparin used can be drastically reduced. The risk of infection is also drastically reduced. Since the inside of the blood chamber a is filled with blood, there is no fear that the air in the air chamber gets mixed into the blood circuit such as the tube 5 as in the conventional case, and the amount of air can be easily adjusted using the syringes 23a and 23b. Along with this, the pressure gauge 22
Blood will not flow into a and 22b, making them unusable. Moreover, the pressure transducers 25a, 25
Since tube b can be used in any position, tube 5 can be made to the shortest length, thereby reducing the amount of extracorporeal circulating blood, and has the advantage of being extremely convenient to handle. have

In FIG. 3, the positive pressure can be generated by the pressure transducer 25b and the restrictor 4 can be omitted. That is, by setting the pressure in the air chamber b of the pressure transducer 25b in advance to a pressure corresponding to the positive pressure, the blood flowing out from the dialyzer 3 will flow through the pressure transducer 25b unless the pressure exceeds the set pressure. Blood cannot flow through the blood chamber a, and therefore, a constant set positive pressure can be applied to the dialyzer 3 regardless of the magnitude of the blood flow rate. In this case the pressure transducer 25b
When the diaphragm 12 shown in FIG. 1 is pressed against the inner wall of the blood chamber a side of the container 11, the inflow port 1
It is necessary to close the opening of the outlet port 15 to the blood chamber a, and provide an appropriate small groove or the like in the opening of the outflow port 15 to the blood chamber a to prevent it from being blocked.

Now, to explain the filter 27, this filter 27 is for removing foreign substances such as small blood clots and air that may be mixed into the blood.
Its structure is as shown in Fig. 4.
Reference numeral 8 is the same as the container 11 of the pressure transducer 25 described above, only the diaphragm 12 is replaced with a filter element 29 of a suitable mesh, and the inside is divided into an inflow side blood chamber 28a and an outflow side blood chamber 28b.
Connecting ports 30a, 3 provided on one side of paired positions diagonally opposite each other with the filter element 29 in between.
Tubes 5, 5 are connected to 0d to allow blood to flow through the filter element 29, and connection ports 30b, 30c on the other side are connected to
The syringe 23c, via the tubes 31a, 31b.
23d are connected and these tubes 31
a and 31b are clamped by clamps 24c and 24d. Thus, the connection port 30c communicates with the outflow side blood chamber 28b on the upper side to form a connection port for air removal, and the connection port 30b communicates with the inflow side blood chamber 28a on the lower side to form a connection port for removing foreign matter. It makes up the mouth. Therefore, blood flowing into the filter container 28 from the connection port 30a flows through the filter element 2.
9 and flows out from the connection port 30d, but if air is mixed in the blood, it will accumulate in the upper part as an air reservoir 31, so air is sometimes removed from the connection port 30c using the syringe 23d. Just do it. Further, foreign matter such as a small blood clot whose passage is prevented by the filter element 29 may be taken out from the connection port 30b using the syringe 23c. Note that this filter 27 is arranged by rotating 90 degrees clockwise from the arrangement shown in FIG.
It can also be used in postures where it is inferior.

In the above embodiment, a Bourdon tube type pressure gauge was used as the pressure gauge 22, but a liquid column type, strain gauge type, or semiconductor type sensor combined with a suitable display device may also be used. It is also possible to detect the upper limit or lower limit of , and use it as a control signal. The pressure gauge 22 may be connected to either the first connection port 16 or the second connection port 17 in a branched manner. The connection port can be omitted from the beginning.

The pressure transducer 25 may alternatively have the shape shown in FIGS. 5 to 7. Fifth
The pressure transducer 32 shown in the figure has a flat container member 33a of a container 33, and connection ports 35a, 3 provided in the flat container member 33a.
5b, but if negative pressure is generated in the blood when using the negative pressure method or other methods, the blood may be allowed to flow in and out from the connection ports 35c and 35d provided in the curved container member 33b. It is sufficient to assume that the flow is inflow and outflow. The pressure transducer 36 shown in FIGS. 6A and 6B has a container 37 with four container members 37a of the same shape facing each other and welding the flange portions 37b with the diaphragm 12 in between. Ports 38a, 38b, and 38c, 38d
Each tube is in a straight line, making it easy to connect the tubes and facilitate blood flow. The pressure transducer 39 shown in FIG.
There is only a blood flow path from a to the connection port 41b.

These pressure transducers 25, 33, 36, 39
3, but also in other hemodialysis methods such as negative pressure method, single needle dialysis method, Japanese Patent Application No. 58-57147 or Japanese Patent Application No. 58-212895.
It can be used in the blood circuit in the dialysis method described in the above issue, and pressure can be measured without contact between blood and air.

In addition to the shape shown in FIG. 4, the filter 27 may have the shape shown in FIG. 6A and B or the pressure transducer 3 shown in FIG. 7, for example.
The diaphragms 12 of Nos. 6 and 39 can be replaced with filter elements.

The pressure transducers 25, 33, 36, 39 and the filters 27, 42 described above can all be made small and strong, and are easy to handle.
It is convenient to carry, has a simple structure, and is easy to manufacture, so it can be manufactured at low cost. Moreover, the pressure transducers 25, 33, 36, and 39 can not only measure the pressure of the blood, but also apply the air pressure in the air chamber b to the blood in the blood chamber a as pressure via the diaphragm 12.

(Effects) According to the present invention, by interposing a closed measuring device that does not come into contact with air near the blood inlet/outlet of the dialyzer interposed in the middle of the blood circuit, the blood can be as much as possible. The blood pressure in the dialysis tube, and therefore the ultrafiltration pressure, can be detected without increasing coagulation.

In particular, according to the present invention, a sealed filter having a specific connection port arrangement that also does not come into contact with air is interposed near the return side of the blood circuit that has passed through the dialyzer to the living body, so that the blood can be passed through the dialyzer without contact with air. Regardless of the blood clotting tendency or other factors, it is possible to not only reliably prevent small blood clots from entering the body, but also to remove these foreign substances from the blood circuit. Air bubbles can be reliably removed, greatly improving patient safety, and the foreign matter and air bubbles can be removed using a syringe.

That is, according to the present invention, although the extracorporeal blood circulation system of the living body formed by the blood circuit of the hemodialysis machine can be formed into a closed circuit that does not come into contact with air, the dialysis machine It has now become possible to accurately measure the ultrafiltration pressure within the blood, and to easily and reliably remove foreign substances such as small blood clots and air bubbles in the blood with extremely simple operations.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a measuring device implementing the present invention, FIG. 2 is a plan view of the pressure transducer shown in FIG. 1, and FIG. 3 is a dialysis apparatus using the measuring device shown in FIG. 1. FIG. 4 is a sectional view showing an embodiment of the filter used in the dialysis apparatus of FIG. 3, FIGS. A sectional view and a side view showing an example, FIG. 8 is a view showing an example of a conventional dialysis device, and FIG. 9 is a view showing a conventional air chamber. 3... Dialyzer, 5, 18, 19... Tube (blood circuit), 11, 33, 37, 40... Container,
12...Diaphragm, a...Blood chamber, b...Air chamber, 22...Pressure gauge, 23c, 23d...Syringe, 26...Measuring device, 27...Filter, 28
...Container, 28a...Inflow side blood chamber, 28b...
Outflow side blood chamber, 29...filter element, 3
0a, 30d... Blood circuit connection port, 30b... Connection port for removing foreign matter, 30c... Connection port for air removal.

Claims (1)

[Claims] 1. In a hemodialysis machine that performs hemodialysis by interposing a dialyzer in the middle of a blood circuit that circulates the blood of a living body extracorporeally, a diaphragm is used to connect the inside of a sealed container near the blood inlet/outlet of the dialyzer. The blood chamber is divided into a chamber and an air chamber, and a blood circuit is connected so that blood flows to the blood chamber, and
A measuring device that detects the blood pressure in the dialyzer by measuring the pressure of the air in the air chamber is interposed, and a similarly sealed container is provided near the return flow side of the blood circuit to the living body. A pair of blood circuits whose interior is divided into an inflow blood chamber and an outflow blood chamber by a filter element, and which are connected to the inflow and outflow blood circuits at one pairing position diagonally in the vertical direction with the filter element in between. The connection port is provided with an air extraction connection port that communicates with the outflow side blood chamber on the upper side of the other paired position, and a foreign matter removal connection port that communicates with the inflow side blood chamber on the same lower side, and A blood circulation device in which filters each having a syringe connected to a connection port for extraction and a connection port for foreign matter extraction are interposed.