JPH0450036Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a pressurization value display device for displaying a control pressurization value in a control operation for the amount of water removed in hemodialysis.

(Prior art) Hemodialysis, which is performed using an artificial kidney device (dialysis device), is used to purify blood by eliminating waste products from the body or taking in what is needed instead of the kidneys when the human body suffers from kidney failure. It is widely used to carry out. The main function of the kidneys is to produce urine, and most of this urine is water, so in hemodialysis it is important to remove water from the blood, so-called water removal. This will be a challenge. Water in the body moves into the blood via intracellular, intercellular, and blood vessels, and it is necessary to remove water at a rate commensurate with this transfer rate.

Recently, however, dialysis membranes used in dialyzers have been improved, and the membrane thickness has become extremely thin, and at the same time, the filtration pores on the membrane surface have become larger, improving the efficiency of removing medium to large molecular weight wastes. This also greatly improves the ultrafiltration coefficient (UFR), which may cause the patient to experience a drop in blood pressure due to the rate at which water is removed during dialysis. As a countermeasure in this case, or as a temporary stop operation during normal operation, the following operation is performed to stop water removal. That is,
In the positive pressure method, the restriction of the restrictor in the blood circuit is released, and in the negative pressure method, the negative pressure of the dialysate is reduced to near zero.

Now, the blood that comes out of the dialyzer returns to the patient's venous blood vessels, but in many patients, there are complex factors such as changes in the shunt of the blood vessel, deformation due to long-term puncture of the cannula, and lesions due to the underlying disease.
There are various problems in the vascular lumen, which increases venous vascular resistance, and when dialyzed blood returns to the venous blood vessel, a resistance force proportional to the amount of blood returned (generally called natural venous pressure) is applied. It is supposed to occur in venous blood vessels. Therefore, even when the above-mentioned operation to stop water removal is performed, this natural venous pressure is applied to the dialyzer as residual pressure, and in reality, a considerable amount of water is removed. For example, 150-200
Blood volume in ml/min (extracorporeally circulating blood volume during normal dialysis)
30-120mmHg depending on the patient, rarely 200mmHg
A natural venous pressure of more than
When using a mmHg/hr dialyzer, 120~
Excessive body fluid removal of 480ml/hr.

In this way, conventionally, even when water removal is stopped, a considerable amount of water is being removed, so the nurse must replenish the patient with replacement fluid commensurate with the amount of water removed while water removal is stopped. This work requires a lot of effort, such as having to be busy with frequent blood pressure measurements, and most of the work relies on experience and knowledge, which is critical to the safety of patients undergoing dialysis. Currently, there are still problems.

(Problem to be solved by the invention) Even when the above-mentioned operation to stop water removal is performed, a considerable amount of water is still removed because natural venous pressure is generated in the venous blood vessels. and
Therefore, the present invention measures and displays natural venous pressure,
Based on this natural venous pressure, the ultrafiltration pressure applied to the dialysis membrane surface is measured and displayed from the pressurization value on the blood circuit side and the pressurization value on the dialysate side, thereby stopping water removal and speed. The purpose is to make it possible to easily control the

(Means for Solving the Problems) In order to solve the above problems, the present invention provides solutions for the downstream side of the dialyzer in the dialysate circuit, the downstream side of the dialyzer in the blood circuit, and the blood circuit further downstream. , are each provided with a pressurizing device and a pressure gauge that measures the pressurized value of each circuit via the pressurizing device, and the downstream side of the dialyzer in the dialysate circuit measured by the above-mentioned pressure gauges. The pressure value, the pressure value on the downstream side of the dialyzer in the blood circuit, the natural venous pressure value propagated to the blood circuit, and the limit applied to the dialysis membrane surface calculated by comparing these pressure values. A configuration is adopted in which a display section is provided to display the filtration pressure value and the filtration pressure value, respectively.

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

FIG. 1 shows an embodiment of a positive pressure method of a dialysis machine. In the figure, 1a and 1b are cannulae, 2 is a blood pump, 3 is a dialyzer, 4 is a tube, and cannula 1a is punctured into human body A.
The blood flowing out from the tube 4a passes through the tube 4b and is sent into the dialyzer 3.
It flows out from c. The dialyzer 3 is connected to a dialysate supply path 5 and a dialysate discharge path 6. A pump P is provided in the supply path 5, and a pressurizing device 8, which will be described later, is provided in the discharge path 6, that is, on the downstream side of the dialyzer 3 in the dialysate circuit 7. Therefore, the dialysate is sent to the dialyzer 3 from the supply path 5 by the pump P,
The dialysate in the dialyzer 3 is discharged from a discharge path 6 via a pressurizing device 8 to a drainage tank or the like as shown by an arrow. On the other hand, the blood that has flowed into the dialyzer 3 and has been dialyzed flows out from the tube 4c, but a pressurizing device 10 is also provided in this tube 4c, that is, on the downstream side of the dialyzer 3 in the blood circuit 9, and the blood is pumped through this pressurizing device. The blood is returned to the human body A via the cannula 1b via the tube 4d via the cannula 10.

The pressurizing device 8 or 10 used in this invention preferably has the structure shown in FIGS. 2a and 2b. That is, in the pressurizing devices 8 and 10, the inside of a sealed container 11 is divided by a diaphragm 11a into two chambers: a liquid chamber a through which dialysate and blood flow and an air chamber b through which pressurized air flows in and out. , container 11
has an inlet 12a and an outlet 1 communicating with the liquid chamber a.
2b, one connection port 13 communicating with the air chamber b is provided. The container 11 is a flat container member 11
A diaphragm 11a having the same outer circumference is sandwiched between the brim portions of the container members 11b and 11c, and these are welded and brought into close contact with each other.The diaphragm 11a is free. In this state, it almost follows the inner surface of the flat container member 11b. The container members 11b and 11c are
It is made of a relatively hard polymeric material such as vinyl chloride, polycarbonate, or silicone rubber, and is integrally molded. The diaphragm 11a has appropriate elasticity and is made of the same material as the container members 11b and 11c to facilitate welding. It is convenient to make the container members 11b, 11c and the diaphragm 11a transparent so that the internal state can be monitored.

Referring also to FIG.
4, pressure gauges 17 and 18 are installed to measure the pressurization value on the dialysate circuit side and the pressurization value on the blood circuit side, respectively.
On-off valves 19 and 20 are provided to communicate and cut off communication between the air pumps 15 and 16 and the pressurizing devices 8 and 10.

By manually operating the air pump 15, the air chamber b of the pressurizing device 8 is pressurized to adjust the amount of deformation of the diaphragm 11a, and the measuring needle of the pressure gauge 17 moves in accordance with this adjusted pressure. , the adjusted pressure can be read from the pressure gauge 17. When the desired regulation pressure value is set, the on-off valve 19 is turned on and off by the pressurizing device 10 of the blood circuit 9.
The on-off valve 20 connected to the air chamber b is switched to the cutoff position to maintain communication between the air chamber b and the pressure gauge 18, but the communication to the air pump 16 is cut off. In addition, air pumps 15, 16
Use a syringe with the needle removed.
As is clear from the above description, the pressure gauges 17 and 18 can be operated by air pressure, such as a Bourdon tube, a bellows, or a diaphragm pressure gauge. It is also possible to output a detection signal by electrically comparing the electrically set value and the pressure signal value.

Further, in the blood circuit 9, a natural venous pressure detection device 21 is interposed further downstream of the pressurizing device 10. This detection device 21 has a configuration similar to that of the pressure devices 8 and 10, but there are some differences, so this will be explained with reference to FIG. The inside of 22 is divided by a diaphragm 21a into two chambers, a blood chamber A and an air chamber B. The blood chamber A is provided with an inlet 23 and an outlet 24 from the blood circuit 9, and an air chamber B is provided with an inlet 23 and an outlet 24 from the blood circuit 9.
A connection port 26 with a pressure monitor tube 25 is provided in the pressure monitor tube 25 . The container 22 consists of a pair of curved container members 22a, 22b.
A diaphragm 21a having the same outer circumference is welded to each other between the respective brim portions of the container members 2b, so that the diaphragm 21a is located in the middle of the pair of container members 22a and 22b in a free state. On the other hand, when a positive pressure is applied inside the container 22, the diaphragm 21a is displaced to the right in the figure, and the inside is moved like a detection device 37 (FIG. 5) used in the negative pressure method described later. When negative pressure is applied, the diaphragm 21a is displaced to the left in the figure. Note that the container members 22a and 22b are made of a relatively hard polymeric material, and the diaphragm 21
A is made of a material having appropriate elasticity, and is preferably made of the same material to facilitate welding, and is preferably made of a transparent material so that the inside can be monitored, the same as the pressure devices 8 and 10. It is.
Naturally, this detection device 21 is also connected to a pressure gauge 27 for measuring the natural venous pressure value through a pressure monitor tube 25.

Next, to explain how to use the dialysis apparatus configured as described above, in FIG. 1, when performing a normal water removal action, on the dialysate circuit side,
The dialysate is supplied to the dialyzer 3 from the supply line 5 by the pump P.
The dialysate in the dialyzer 3 is discharged to the outside from the discharge path 6 via the pressurizing device 8. On the other hand, on the blood circuit side, the blood flowing out from the human body A is pumped by the blood pump 2. Blood is sent to the dialyzer 3, where water is removed (dialyzed) and the blood is transferred to the pressurizing device 1.
In this case, in order to remove a relatively large amount of water in general, a pressure higher than the patient's natural venous pressure is applied to the pressurizing device 10 on the blood circuit side. At the same time, the pressurizing device 8 on the dialysate circuit side
It is sufficient to bring the pressure to zero, that is, to the open state.

That is, the detection device 2 provided downstream of the pressurizing device 10
The natural venous pressure value is read by the pressure gauge 27 of No. 1, and the on-off valve 20 is switched to connect the air chamber b of the blood circuit side pressurization device 10, the air pump 16, and the pressure gauge 18.
In this state, the air chamber b is pressurized by the air pump 16, and after reading the pressure value set to the natural venous pressure value or higher by the pressure gauge 18, Block the passage to air pump 16. Similarly, the pressurizing device 8 on the dialysate circuit side
Pressure gauge 1 so that the pressure in air chamber b becomes zero at
7 to read and set.

Through the above operations, the blood chamber a of the pressurizing device 10 is
(FIG. 2) is pressurized via the diaphragm 11a, so the blood passes through the blood chamber a while pushing back the diaphragm 11a by a pressure greater than this pressurizing force. The pressurizing force of the blood circuit side pressurizing device 10 is directly applied to the blood circuit side, and this pressure becomes the ultrafiltration pressure applied to the dialysis membrane surface in the dialyzer 3.
Water will be removed in proportion to this pressure.

Next, a case in which water is removed within the range of natural venous pressure will be described. As mentioned in the prior art section, the human body is always loaded with natural venous pressure, and even if an operation is performed to stop water removal, a considerable amount of water will actually be removed due to natural venous pressure. be.

Figure 4 shows that the effective ultrafiltration coefficient (UFR) is 4.
This is a graph showing the relationship between the venous pressure (ultrafiltration pressure) generated on the dialysis membrane surface and the amount of ultrafiltration (amount of water removed) when using a dialysis machine with ml/mmHg/hr.
For example, the natural venous pressure measured by pressure gauge 27 is 140
If it is mmHg, 560 ml/hr of excessive body fluid will be removed.

Depending on the patient, it may be necessary to remove water in small amounts due to weakened physical strength. In some cases, the amount of water removed is within the amount of water removed by natural venous pressure by adjusting the load so as not to place an excessive burden on the patient.

In this operation, first, the pressure in the air chamber b of the blood circuit side pressurizing device 10 is set to zero while being read by the pressure gauge 18. Therefore, in this state, the blood circuit 9 is loaded with the natural venous pressure (for example, 140 mmHg) measured by the pressure gauge 27 of the detection device 21. Next, the air chamber b of the dialysate circuit pressurizer 8 is pressurized by the air pump 15 to apply pressure to the dialysate chamber a (Fig. 2), thereby increasing the membrane surface inside the dialyzer. A pressure of, for example, 30 mmHg is applied to the pressure gauge 17 while being controlled and set. With this operation, the membrane surface of the dialyzer 3 has a natural venous pressure (140 mmHg) - dialysate pressure (30
mmHg) = 110 mmHg is loaded as ultrafiltration pressure, and when the effective UFR of this dialysis membrane is 4 ml/mmHg/hr, the natural venous pressure (140
440, which is lower than the amount of water removed (560ml/hr) by mmHg)
It can be seen that the amount of water removed is ml/hr.

Furthermore, the case where water removal is stopped will be explained. In this operation, first, the air pump 16 is set so that the pressurizing force in the air chamber b of the blood circuit side pressurizing device 10 becomes zero while being read by the pressure gauge 18.
In this state, the dialyzer 3 is loaded with the natural venous pressure read by the pressure gauge 27. Next, by pressurizing the air chamber b of the dialysate circuit side pressurizing device 8 with the air pump 15, the dialysate chamber a is pressurized via the diaphragm 11a (second
), thereby reducing the dialysate pressure in the dialysate circuit 7 before passing through the pressurizing device 8 to the natural venous pressure, e.g.
Adjust while reading the pressure gauge 17 so that it is 140mmHg. By this operation, no differential pressure, that is, ultrafiltration pressure is applied to the membrane surface within the dialyzer 3, and therefore water removal is not performed and the water removal is stopped.

The above explanation is about the configuration of a dialysis apparatus using the so-called positive pressure method, but the configuration and operation are the same in the negative pressure method described below.

Figure 5 shows a dialysis machine using the negative pressure method.
To mention only the differences with the positive pressure method, the suction pump 2
Negative pressure is generated on the dialysate circuit side by the dialysis fluid circuit 8 and the dialysis device 29, and the discharge force of the discharge pump 36 installed near the dialysis device 29 is normally higher than the suction force of the suction pump 28. is set to be weak. On the downstream side of the dialyzer 3 in the dialysing fluid circuit 7, there is the aforementioned pressurizing device 8, a pressure gauge 17 that measures the internal pressure, that is, the pressure applied to the dialysate, and air that controls the internal pressure to the pressurizing device 8. A pump 15 is provided, and a detection device 37 for detecting the suction pressure (negative pressure) of the pump and a pressure gauge 38 for measuring the pressure are further provided on the upstream side of the suction pump 28. Note that the detection device 37 has the same structure as the natural venous pressure detection device 21. Note that the blood circuit 9 does not need to be provided with a pressurizing device as in the positive pressure method described above, and even if provided, it is necessary to keep it open at all times. The fact that a natural venous pressure detection device 21 and a pressure gauge 27 for measuring the internal pressure are provided downstream of the dialyzer 3 in the blood circuit 9 is the same as in the positive pressure method. The natural venous pressure indicated by the pressure gauge 27 is always applied. This negative pressure method is operated by adjusting the air pump 15 while reading the pressure gauge 17 so that the pressure applied to the pressurizing device 8 becomes zero, and reducing the negative pressure generated by the action of the suction pump 28 and the restrictor 29. In other words, in proportion to the suction force of the suction pump 28, that is, the suction pressure (negative pressure) value on the upstream side of the pump 28 read by the pressure gauge 38, above the natural venous pressure. The general water removal effect can be performed. In addition, when removing water within the range of natural venous pressure, reduce the suction force of the suction pump 28, increase the pressure of the discharge pump 36, and then, while reading the pressure gauge 17, pressurize the pressurizer 8 until the pressure is within the natural venous pressure. All you have to do is apply pressure, and if water removal is to be stopped, the natural venous pressure is read using the pressure gauge 27.
There is no difference from the positive pressure method in that it is only necessary to operate the air pump 15 to apply the same pressure to the pressurizing device 8.

From the above explanation, the following can be concluded.

First, in the positive pressure method, if the pressure value P 1 displayed on the pressure gauge 18 of the blood circuit side pressurization device ₁₀ is higher than the pressure value P ₂ displayed on the pressure gauge 27 of the natural venous pressure detection device 21, , the pressure value displayed on the pressure gauge 18 of the blood circuit side pressurization device 10
From P ₁ to the pressure gauge 17 of the dialysate circuit side pressure device 8
The value obtained by subtracting the pressure value _P3 displayed in is the ultrafiltration pressure value P. On the other hand, if the pressure value P ₁ displayed on the pressure gauge 18 of the blood circuit side pressurization device 10 is lower than the pressure value P ₂ displayed on the pressure gauge 27 of the natural venous pressure detection device 21, the natural venous pressure Pressure value displayed on the pressure gauge 27 of the detection device 21
From P ₂ to the pressure gauge 17 of the dialysate circuit side pressure device 8
The value obtained by subtracting the pressure value _P3 displayed in is the ultrafiltration pressure P.

In the negative pressure method, the dialysate circuit side pressure device 8
If the pressure value P ₃ displayed on the pressure gauge 17 is zero, the suction force of the dialysate circuit passing through the dialyzer 3, that is, the negative pressure on the upstream side of the suction pump 28, is the value P read by the pressure gauge 38. ₄ and the pressure value P ₂ displayed on the pressure gauge 27 of the natural venous pressure detection device 21
The value added is the ultrafiltration pressure value P, and the pressure value
If P ₃ is positive or greater than zero, the natural venous pressure value
The pressure value obtained by subtracting the dialysate circuit side pressure value _P3 from _P2 becomes the ultrafiltration pressure P.

By measuring the ultrafiltration pressure value P, the amount of water removed per unit time can be immediately calculated.

The present invention focuses on the above conclusion, and by attaching a display unit to the dialysis control device that displays the above series of pressure values, the amount of water removed can be controlled accurately and quickly. This is what I did.

FIG. 6 schematically shows the display device 30. Reference numeral 31 is a display section for displaying the blood circuit side pressurization value _P1 , and as shown by the dashed line, the blood circuit side pressurization device 10 The analog display of the pressure gauge 18 is converted into a digital display by interposing a well-known A/D converter. Similarly, 32 is the natural venous pressure value
This is a display unit that displays P ₂ and is operatively connected to the pressure gauge 27 of the natural venous pressure detection device 21. 33
is a display unit that displays the dialysate circuit side pressurization value _P3 , and is interlocked and connected to the pressure gauge 17 of the dialysate circuit side pressurizer 8. 39 is a display section that is displayed only in the negative pressure method and displays the pressure (negative pressure) value _P4 of the upstream circuit of the suction pump 28 in the dialysate circuit, and is interlocked and connected to the pressure gauge 38 of the dialysate circuit. . 34 is a display unit that displays the ultrafiltration pressure value P, and in actual control operations, this pressure value P
Since this will be done while reading, it is preferable to have a larger display area than other display sections to make it easier to see.

The ultrafiltration pressure value P is determined by measuring the blood circuit side pressurization value P ₁ , the natural venous pressure value P ₂ , the dialysate circuit side pressurization value P ₃ , and the suction pump discharge side pressure value P ₄ in the dialysate circuit. Therefore, what can be obtained by comparing and calculating these pressure values using a well-known arithmetic circuit is as derived from the above conclusion.

That is, in the case of the positive pressure method, the conclusions shown in the above section are shown in a flowchart as shown in FIG. 7. When the blood circuit side pressurization value P ₁ is higher than the natural venous pressure value P ₂ , the ultrafiltration pressure value P is obtained by subtracting the dialysate circuit side pressurization value P ₃ from P ₁ . For example, P ₁ is 150
mmHg, P ₂ is 130mmHg, P ₃ is 0mmHg,
P is 150 mmHg, and this value will be displayed on the ultrafiltration pressure display section 34. When P ₁ is lower than P ₂ , P is the value obtained by subtracting P ₃ from P ₂ . For example, P ₁ is 0 mmHg, P ₂ is 130 mmHg, P ₃ is 80
In the case of mmHg, the ultrafiltration pressure display section 34 shows 50mmHg.
is displayed, and if the ultrafiltration coefficient (UFR) of the dialyzer 3 to be used is 4ml/mmHg/hr.
A water removal amount of 200 ml/hr can be instantly converted, and based on these values, the water removal amount can be quickly and easily controlled.

Regarding the negative pressure method, the conclusions shown in the above section are shown in a flowchart as shown in Figure 8. In other words, in the negative pressure method, the blood circuit side pressurization value is close to zero and can be ignored. Therefore, if the dialysate circuit side pressurization value P ₃ is zero, the natural venous pressure value P ₂ and,
The ultrafiltration pressure value P is the sum of the negative pressure (suction force) applied to the dialysate circuit, that is, the suction pump upstream negative pressure value _P4 . Furthermore, if the pressure value P ₃ is greater than zero, it naturally means that the pressure on the dialysate side is being applied to the dialyzer 3, so the natural venous pressure value P ₂
The ultrafiltration pressure value P is obtained by subtracting the dialysate circuit side pressure value _P3 from the dialysate circuit side pressure value P3. In this case, if the pressure applied to the ultrafiltration membrane by the pressurization value P ₃ becomes equal to P ₂ , the ultrafiltration pressure is zero, so water removal is stopped, and the filtration is stopped by P ₃ . The pressure applied to the membrane is P ₂
If it is lower, water will be removed within the range of natural venous pressure _P2 . This negative pressure method is no different from the positive pressure method in that the amount of water removed can be immediately calculated by reading the ultrafiltration pressure value P.

In addition, numeral 35 in the figure is a water removal method display section, which is adapted to appropriately switch and display the distinction between positive pressure method and negative pressure method.

(Effects) According to the present invention, since the ultrafiltration pressure loaded on the dialyzer can be directly read from the display device, the amount of water removed can be easily and quickly controlled in response to changes in the patient's condition. This not only greatly reduces the workload of nurses, but also greatly improves patient safety.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram of a dialysis machine using a positive pressure method, which is an embodiment of the present invention, Fig. 2a and Fig. 2b
3 is a vertical sectional view of the pressure detection device, which is the other important part, and FIG. 4 shows the relationship between venous pressure and ultrafiltration rate in the dialyzer. 5 is a schematic explanatory diagram of a dialysis apparatus using a negative pressure method which is another embodiment of the present invention, and FIG. 6 is a schematic explanatory diagram of a display device which is the main part of the present invention. FIG. 7 is a flowchart schematically showing the operating state of one embodiment of the present invention, and FIG. 8 is a flowchart schematically showing the operating state of another embodiment. 7... Dialysate circuit, 8... Dialysate circuit side pressurizing device, 9... Blood pressure circuit, 10... Blood circuit side pressurizing device, 21... Natural venous pressure detection device, 30... Display device, 31 ...Blood circuit side pressurization value display section, 32...
... Natural venous pressure display section, 33 ... Dialysate circuit side pressurization value display section, 34 ... Ultrafiltration pressure value display section, 39 ...
...Pressure value display section on the suction pump discharge side in the dialysate circuit.

Claims (1)

[Scope of utility model registration request] A pressurizing device is provided downstream of the dialyzer in the dialysate circuit, downstream of the dialyzer in the blood circuit, and further downstream of the dialyzer, and a pressurizing value of each circuit is transmitted via the pressurizing device. A pressure gauge is provided to measure the pressure value on the downstream side of the dialyzer in the dialysate circuit measured by each of the pressure gauges, the pressure value on the downstream side of the dialyzer in the blood circuit, and the pressure value on the downstream side of the dialyzer in the blood circuit. A display device in a hemodialysis control device, comprising a display unit that displays a propagated natural venous pressure value and an ultrafiltration pressure value applied to a dialysis membrane surface calculated by comparing and calculating these pressure values. .