JPS6040302B2 - Double filtration plasma exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for safely and stably performing double filtration type blood count separation and exchange.

Recently, the blood plaque separation and exchange method has been known as a treatment for liver failure, liver failure, autoimmune diseases, and the like.

This method is generally similar to hemodialysis, in which blood is continuously separated in a closed extracorporeal circulation circuit and blood cell components are returned to the body, but in this case, some of the blood that is discarded is contains low-molecular-weight active ingredients in a state bound to high-molecular-weight toxins, etc., and if this is also removed, more fluid replacement will be required. For this reason, various attempts have been made to efficiently remove such high molecular weight substances, and among them, the double filtration type blood count separation and exchange method is attracting attention. This method uses two molecules with different molecular weights but-off.
Using a different kind of filtration device, the first filtration device separates blood components into blood count components and blood cell components, and then the second filtration device separates the blood-unfriendly components into high-molecular weight substances and low-molecular-weight substances. This is a method in which only high molecular weight substances are selectively removed, while low molecular weight substances are returned to the body. In systematizing such a method, the present invention automatically controls the pressure and flow rate in the closed extracorporeal circulation circuit, supplies an appropriate amount of orange juice, and safely and stably achieves a double filtration type blood count. The purpose is to provide a device that can perform separation and exchange.

FIG. 1 shows an embodiment of the present invention. To explain its structure and operation, firstly, blood is passed from the patient through the blood inlet 1 to the pump M. Blood is introduced into the blood reservoir 4 and
to be stored.

The subsequent first filter 5 is partitioned by a filter 2 such as a polyvinyl alcohol membrane, and the blood introduced from the blood reservoir 4 is passed through the positive pressure of the pump M on the blood introduction side and the blood pseudo-drawing circuit 8. The blood cells are separated into blood cell components and blood* components through the filtration membrane 2 by the negative pressure generated by the pump M2 provided in the filtration membrane 2.
The blood components separated here are sent to the second filtration device through the blood elutriation reservoirs 7 and 9 provided in the blood acid derivation circuit 8, but the pressure of this separated blood elutriation is If the set pressure is exceeded (for example, if abnormal negative pressure occurs), there is a risk of hemolysis, etc. Therefore, in the present invention, the tenth
A means for detecting the differential pressure between the blood inlet side and the bran outlet side of the week device 5, and a differential pressure gauge P between the blood inlet side and the bran outlet side as shown in FIG. 1, for example, are provided, and the differential pressure gauge P, By interlocking control with
By increasing the pressure F, the flow rate is adjusted so that the differential pressure gauge P becomes the set pressure or less than the set pressure.

In the case of this embodiment, the differential pressure gauge P is configured to measure the hair pressure in the blood reservoir 4 located in front of the first filtration device 5 and the dish bran reservoir 7 located in front of the pump station. The flow rate of the pump M2 is controlled at 15 to 20 Hg or less so that this pressure difference is 10 Mg or less, preferably 60 Hg or less. On the other hand, the inside of the second filtration device 11 is partitioned by a filtration membrane 10 such as an ethylene pinyl alcohol membrane, and the blood acid introduced into the second filtration device 11 is transferred to the pump M2 and a discharge circuit described below. The positive pressure generated by the difference in flow rate with the pump M3 provided at 12 separates the substance into a high molecular weight substance and a low molecular weight substance.

The separated high molecular weight substance is led out through the discharge circuit 12 and discharged into the storage container 13, but in this case, the pump M2
If the flow rate of the filter and soil becomes unbalanced, abnormal pressure will be applied to the second filter 11, making it impossible to obtain stable filtration and separation effects. Therefore, in the present invention, the flow rate ratio of the pumps M2 and M3 is controlled in conjunction with each other to adjust the flow rate ratio between the amount of blood bran introduced and the amount of high molecular weight substances discharged in the second filtration device 11 to a predetermined value.

For example, if the flow rate of the pump M2 is 15 to 20 sails/min, the flow rate of the pump M3 is 1'3 to 1' daughter 0chi3.
It will be automatically controlled to be ~5 fences/minute. In addition, P2 in the figure is a pressure gauge provided in the blood reservoir 9, and when high pressure is applied to the second filtration device 11, the filtration membrane 10
Since there is a risk of a puncture, this pressure gauge P2 is used to monitor the pressure. On the other hand, the low molecular weight substances separated in the second filtration device 11 are sent to the blood reservoir 14 through the derivation circuit i5, and are mixed with blood cell components sent from the first filtration device 5 through the derivation circuit 17. After merging, they will be returned to the patient's body.

In order to supplement the dish bran removed in the second filtration device 11, a replacement fluid such as albumin or HES is sent from the replacement fluid container 16 to the blood reservoir 14 through the introduction circuit 18.
In the present invention, when introducing this replacement fluid, the introduction circuit 1
By controlling the movement of the pump M4 provided for introducing the liquid into the tub and the pump M3 provided in the discharge circuit 12 for the high molecular weight substance, the amount of the high molecular weight substance drawn out and the amount of the similar fluid injected become equal. The flow rate is adjusted accordingly. For example, as mentioned above, if the flow rate of the pump M3 is 3 to 5 per minute, the pump station is adjusted to have the same flow rate, so that the replacement fluid is injected into the blood reservoir 14 in just the right amount. That will happen. Note that in this embodiment, the blood reservoir 1
4 is equipped with a pressure gauge P3 to monitor the patient's condition (anemia, etc.) and troubles with the shunt. According to the present invention, the interlocking control means for each of the pumps M2, M3, M4 may be electrically controlled; however, each circuit 8, 1
Two or three tubes constituting the tubes 2 and 13 may be combined as appropriate and squeezed at the same time.

As an example, as shown in FIG.
By setting the inner diameters of tubes 2a and 18a on the 4th side and simultaneously squeezing these tubes with the same drive roller 20, it becomes possible to adjust the flow rate according to the diameter of each tube. What has been explained above is an example of the present invention, and the first filter 5 and the second filter 1
1 may be of a hollow fiber type or other types, and other devices may also be modified according to the spirit of the present invention. According to the present invention, when performing double filtration type blood count separation, the first filtration device includes a means for detecting a difference in temperature between the blood introduction side and the blood extraction side, and a blood extraction side pump. Because of the interlocking control, by detecting the pressure applied to the filtration membrane of the first filtration device from the relative pressure on the inlet side and outlet side, stable membrane pressure can be maintained at all times. Hemolysis and a decrease in filtration efficiency due to blood cell adhesion can be prevented.

In addition, the pump installed in the high molecular weight substance discharge circuit of the second filtration device is controlled in conjunction with the pump installed in the dish ring derivation circuit to maintain a predetermined flow rate ratio. Stable positive pressure is always applied to the filtration membrane of the filter,
It is possible to prevent abnormal pressure from being applied to the membrane, and it is also possible to efficiently separate blood acid components.

Furthermore, since the replacement fluid introduction pump is controlled in conjunction with the pump of the high molecular weight substance discharge circuit, it is possible to inject into the body exactly the same amount of replacement fluid as the amount of discharge of the high molecular weight substance.

As described above, according to the present invention, the flow rate and pressure in the closed extracorporeal circulation circuit equipped with the first filter and the second filter are automatically controlled to always be at predetermined values. This is an extremely effective invention that enables safe and stable treatment.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the device according to the present invention;
FIG. 2 is a schematic diagram showing another embodiment of the invention. In the figure, 5 is the 10th week organ, 8 is the blood acid derivation circuit, and 11 is the 2nd week organ.
filtration device, 12 is a high molecular weight substance discharge circuit, 15 is a low molecular weight substance derivation circuit, 18 is a replacement fluid introduction circuit, M, , M2, M3
, M4 are pumps, P is a differential pressure gauge, and F2 and P3 are pressure gauges. Figure 1 Figure 2

Claims (1)

[Claims] 1 A closed extracorporeal circulation circuit is equipped with a first filter and a second filter, and the first filter separates blood drawn from the body into blood cell components and plasma components, and the plasma component is Furthermore, a second filtration device separates high-molecular weight substances and low-molecular weight substances, and the blood cell components and low-molecular weight substances are combined and, after adding replacement fluid, are returned to the body.Double filtration type plasma separation exchange In the apparatus, a differential pressure detection means for detecting a differential pressure between the blood introduction side and the plasma output side in the first filter is provided, and the differential pressure detection means is provided in a circuit leading to the first filter and the second filter. A pump capable of adjusting the flow rate to a set pressure or below the set pressure by interlocking control with the means is provided, and a pump is provided in the high molecular weight substance discharge circuit of the second filter by interlocking control with the pump. A pump is provided which can adjust the flow rate so that the flow rate ratio between the amount of plasma introduced and the amount of high molecular weight substances discharged is a predetermined value, and the replacement fluid introduction circuit is equipped with a pump installed in the high molecular weight substance discharge circuit of the second filtration device. 1. A double filtration type plasma separation and exchange device, characterized in that a pump is provided which can adjust the flow rate so that the amount of discharge of the high molecular weight substance and the amount of replacement fluid injected are equal to each other through interlocking control.