JPH0822312B2 - Blood processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a blood processing apparatus for performing a large amount of fluid replacement, particularly a blood processing apparatus applicable to a blood hyperdialysis method (HDF) or a continuous blood flow method (CHF). It is about.

(Prior Art) Conventionally, a hemodialysis method has been applied to remove toxic substances present in the blood of patients with renal failure, liver failure, etc., but some patients are treated sufficiently by the hemodialysis method. Sometimes you can't. In recent years, hemodialysis method in which dialysis and bleeding are combined with such a patient, the separated fluid (a part of dialysis effluent) is discarded, and a replacement fluid such as artificial body fluid is mixed with blood, or body fluid containing toxic substances rather than blood , For example, a large amount of water containing a medium molecular weight substance, or plasma containing waste products is continuously over-separated, the separated liquid is discarded, and a fresh and healthy plasma component or artificial replacement fluid such as artificial body fluid. The continuous blood method of mixing blood with blood again is performed.

In such a treatment method, a liquid (or a part of dialysate) that is discarded to prevent side effects such as hypotension shock.
Therefore, it is absolutely necessary to balance the replacement fluid mixed with blood. For this reason, a normal drainage pump and a replacement fluid pump are used to set both flow rates to the same value, or a double tubing pump is used to set the drainage fluid rate and the replacement fluid flow rate to the same value. .

(Problems to be solved by the invention) However, the amount of fluid replacement (drainage) is large, and particularly when it reaches 20 l as seen in recent treatment cases, blood treatment takes a long time and the conventional two pumps or In the method using the double tubing pump, the flow rate changes due to the pressure fluctuation before and after the pump, and it becomes extremely difficult to maintain the balance between the replacement fluid amount and the drainage amount.

Therefore, it is an object of the present invention to provide a blood processing apparatus that can reliably maintain the balance between the replacement fluid amount and the drainage amount even in a long-time blood treatment.

(Means for Solving the Problems) The present invention provides a hemodialyzer or hemoperfusion device provided in a blood extracorporeal circulation channel, and a dialysate outlet channel or hemoperfusion device provided in the hemodialyzer. A drainage flow path that is connected to the dialysate discharge flow path or the dialysate discharge flow path or the liquid discharge flow path, and discharges the dialysate or a part of the liquid from the flow path into a drainage container. A flow path, a replacement fluid flow path connected to the blood extracorporeal circulation flow path through a replacement fluid pump, for injecting a replacement fluid in a replacement fluid container into the flow path, and a flow path bypassing the replacement fluid pump or the drainage pump, A forward / reverse rotatable correction pump provided in the bypass flow path, a weight measuring unit for measuring the total weight of the liquid container and the replacement liquid container, and a total weight of the two containers measured by the weight measuring unit. Deviation between the two values while comparing the value with the initial measurement value measured at the start of blood treatment And a rotation control circuit for rotating the correction pump in the normal and reverse directions until the value becomes zero.

(Example) Next, one example of the blood processing apparatus of the present invention will be described with reference to the drawings. FIG. 1 is an example of a device applied to a hemodialysis method, and a dialysate introduction flow path 3 connected to a dialysate inlet and an outlet of a hemodialyzer 2 provided in a blood extracorporeal circulation flow path 1, respectively. A dialysate outlet channel 4, a drainage channel 7 connected to the dialysate outlet channel 4 for discharging a part of the dialysate into a drainage container 6 by a drainage pump 5, and an extracorporeal blood circulation channel 1. A replenishment fluid flow path 10 that is connected to inject the replenishment fluid in the fluid replenishment container 8 into the extracorporeal blood circulation flow passage 1 by a fluid replenishment pump 9, and a forward / reverse correction pump 12 provided in a fluid passage 11 that bypasses the fluid replenishment pump 9. ,
It comprises a weight measuring means 13 for measuring the total weight of the drainage container 6 and the replacement fluid container 8 and a rotation control circuit 14 for balancing the drainage amount and the replacement fluid amount by rotating the correction pump forward and backward.

The blood extracorporeal circulation flow path 1 is a flow path for taking out blood from a patient and returning purified blood to the patient. Blood is taken out by a blood pump 15. Further, a replacement fluid flow channel 10 is connected to the blood extracorporeal circulation flow channel 1 on the downstream side of the hemodialyzer 2.

The hemodialyzer 2 has a hollow fiber or sheet-shaped membrane such as kyuproammonium cellulose, polyacrylonitrile, or polyvinyl alcohol contained in the housing, and the inside of the housing is fractionated by the membrane into the blood side and the dialysate side. It is called a type artificial kidney or a keel type artificial kidney.

The dialysate introduction flow path 3 is a flow path that connects a dialysate inlet of the hemodialyzer and a dialysate supply device (not shown), and a flow meter, a heater and the like are attached to this flow path.

The dialysate outlet channel 4 is a channel that is connected to the dialysate outlet of the hemodialyzer and discharges the dialysis effluent. A negative pressure pump 16 for introducing the dialysate into the hemodialyzer is attached to this flow path.

Further, a drainage fluid passage 7 is connected to the dialysate outlet passage 4 upstream of the negative pressure pump.

Replacement fluid pump 9 provided in replacement fluid channel 10 and drainage channel 7
The drainage pumps 5 provided in the above may be independent roller pumps or double tubing type pumps. Normally, a double tubing type pump is used.

The forward / reverse rotatable correction pump 12 provided in the flow path 11 bypassing the replacement fluid pump 9 is normally 20% of the flow rate of the replacement fluid pump.
It has the following flow rates, and receives a signal from a rotation control circuit 14 to be described later, and rotates normally and reversely so as to maintain the balance between the replacement fluid amount and the drainage amount.

The weight measuring means 13 measures the total weight of the drainage container 6 and the replacement liquid container 8, and a known measuring means, usually a load cell, is used.

The rotation control circuit 14 comprises a circuit 20 for receiving the signal from the weight measuring means 13 and storing an initial value of the weight at the start of blood processing, and a comparison circuit 21, wherein the comparison circuit 21 measures the initial value and the total weight. The values are compared, and when the initial value <the measured value, a signal for rotating the correction pump in the positive direction is transmitted to the drive circuit 22 to drive the correction pump and increase the replacement fluid injection amount. On the other hand, when the initial value> measured value, a signal for rotating the correction pump in the reverse direction is transmitted to the drive circuit 22 to drive the correction pump to reduce the injection amount of the replacement fluid. The correction pump is driven until the deviation value between the measured value and the initial value becomes zero, and when the deviation value between the two is zero, a signal for stopping the correction pump is sent to the drive circuit 22 to stop the correction pump.

Next, the operation of the above configuration will be described. Blood pump 15
When blood is taken out from the patient within the range of 100 to 200 ml / min by the rotation of the blood, the blood is circulated to the hemodialyzer 2 and the human body. In the above hemodialyzer, a dialysate supply device (not shown)
The dialysate is supplied to the hemodialyzer 2 via the dialysate introduction flow path 3, and the dialysate drainage flow path 4 discharges the dialysate drainage solution containing the unnecessary substance and water that has permeated the membrane. A part of the dialysate drainage liquid is discharged into the drainage container 6 from the drainage flow passage 7 provided in the dialysate discharge flow passage 4. On the other hand, the blood extracorporeal circulation flow path 1 is filled with the same amount of the replacement liquid as the drained liquid discharged from the replacement liquid container 8 through the replacement liquid flow path.

The total weight of the replacement fluid container 8 and the drainage container 6 is always measured by the weight measuring means 13, and the signal is transmitted to the rotation control circuit 14. The rotation control circuit 14 compares the weight measurement value at the start of blood processing with the measurement value, and when the initial value <measured value, the correction pump 12 rotates forward to increase the replacement fluid amount, and when the initial value> measured value. The correction pump rotates in reverse and the amount of replacement fluid decreases. The rotation of the correction pump stops when the measured value becomes equal to the initial value. Therefore, the replacement fluid amount and the drainage amount can be constantly balanced.

By the way, although the drainage amount and the replacement fluid amount are set to be the same, in reality, the eccentricity of the shafts of the drainage pump 5 and the replacement fluid pump 9 and the dimensional error of the tube diameter, and further, the pump 5,
It is inevitable that there will be a flow rate error due to changes in the effective volume of the internal volume of the tube due to the differences in suction and discharge pressures of 9.

When the above flow rate error occurs, the circulating blood volume of the patient changes, which increases the burden on the circulatory system of the patient, resulting in a very alarming state.

However, in the above configuration, the correction pump is rotated in the forward and reverse directions to adjust the replacement fluid amount so that the total weight of the replacement fluid container and the drainage container is always equal to the total weight at the start of blood processing, and the drainage amount and the replacement fluid amount are adjusted. The difference from the amount can be remarkably reduced, and therefore the above safety can be further promoted.

In the above-described embodiment, the case of performing hemodialysis is described as an example. However, for example, in the case of continuously providing blood as shown in FIG.
By connecting the drainage flow path 7 upstream of the liquid pump 32 provided in the liquid flow path 31, it is possible to maintain a balance between the liquid quantity and the replacement fluid quantity. And its description is omitted.

Further, in the above description, an example in which the bypass flow passage is provided on the replacement liquid pump side has been described, but the bypass flow passage may be provided on the drainage pump side. In that case, the forward / reverse operation of the correction pump is reversed. Further, the replacement fluid channel may also be connected between the blood pump of the extracorporeal blood circulation channel and the hemodialyzer or the hemofilter.

(Effects of the Invention) As described above, the present invention has a simple configuration in which the total weight of the replacement fluid container and the drainage container is measured, and the correction pump is rotated forward and backward in comparison with the total weight at the start of blood treatment. It is possible to provide a blood processing apparatus that can reliably balance the amount of liquid and the amount of drainage, contribute to ensuring safety, and have excellent operability.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of the blood processing apparatus according to the present invention, and FIG. 2 is a block diagram showing another embodiment. 1 ... blood extracorporeal circulation flow path 2 ... hemodialyzer 4 ... dialysate outlet flow path 5 ... drain pump 6 ... drain container 7 ... drain path 8 ... replacement container 9 ... replacement liquid Pump 10 …… Replacement fluid flow path 11 …… Bypass flow path 12 …… Compensation pump 13 …… Weight measuring means 14 …… Rotation control circuit

Claims (1)

[Claims] 1. A hemodialyzer or hemoperfusion device provided in an extracorporeal blood circulation channel, and a dialysate outlet channel or a fluid outlet channel provided in the hemodialyzer. A drainage flow path connected to the dialysate discharge flow path or the liquid discharge flow path via a drainage pump and discharging a dialysate or a part of the liquid from the flow path into a drainage container; A replacement fluid channel connected to the circulation channel via a replacement fluid pump for injecting the replacement fluid in the replacement fluid container into the channel, a channel bypassing the replacement fluid pump or the drainage pump, and a bypass channel A forward / reverse rotatable correction pump, a weight measuring means for measuring the total weight of the liquid container and the replacement fluid container, a measurement value of the total weight of the two containers measured by the weight measuring means, and a measurement value at the start of blood treatment. While comparing with the initial measured value, set the correction pump until the deviation value of both becomes zero. Blood treatment apparatus comprising a rotation control circuit to reverse rotation.