JP2007075541A - Extracorporeal circulation assisting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an extracorporeal circulation assisting device, safely and effectively generating pulsatile flow in assisted extracorporeal circulation assisting the heart of a patient. <P>SOLUTION: This extracorporeal circulation assisting device includes: a blood removable blood tube 111; a centrifugal pump 112 connected to the blood removable blood tube; a blood delivery blood tube 115; an artificial lung 114 connected to the blood delivery blood tube; a bypass blood tube 116; and a means for varying the blood passage sectional area in synchronization with the pulsation of the heart on the downstream side from a connecting part of the blood delivery blood tube and the bypass blood tube. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a blood assisted circulation device used for assisting cardiopulmonary function.

  Conventionally, blood auxiliary circulation methods include a method using an arteriovenous bypass, a method using an auxiliary artificial heart, and an intra-aortic balloon pumping method (IABP method).

  Although the method using an auxiliary artificial heart has the highest blood assisted circulation effect, it requires a thoracotomy, which places a heavy burden on the patient and further complicates the operation. In addition, the IABP method is easy to operate, but since blood is delivered by inflation and deflation of a balloon inserted into the aorta, the amount of blood that can be delivered is small and the auxiliary circulation effect is low.

  On the other hand, the arteriovenous bypass method has a lower auxiliary circulation effect than the method using the auxiliary artificial heart, but the burden on the patient is small because there is no need for thoracotomy. Furthermore, the auxiliary circulation effect is higher than the IABP method. Have.

  The blood assisted circulation apparatus used for the arteriovenous bypass method includes a blood removal blood tube, a blood pump, an artificial lung, and a blood delivery blood tube connected to one end of a blood removal catheter inserted and placed through the femoral vein. At least. Further, a constant pressure pump (for example, a centrifugal pump) is used as the blood pump.

  Furthermore, in order to realize the active blood transfer to the coronary arteries while reducing the burden on the patient's cardiac function, the blood flow tube is clamped in synchronization with the patient's pulsation, causing pulsatile flow, An arteriovenous bypass method has been proposed in which the load during the systole of the heart is reduced and the blood flow volume to the coronary artery in the diastole is secured, and this is combined with IABP to increase the effect.

JP-A-2-149174

  However, this method of clamping a blood supply blood tube is based on repeated rapid flow / pressure changes that occur during repeated tube closure / opening, resulting in hemolysis, rotor fatigue of centrifugal pumps, and plasma leaks in artificial lungs. There is a concern about the promotion. There is also a disadvantage that a new device for clamping the blood tube is required.

  Therefore, the present invention provides an extracorporeal circulation assist device for avoiding such inconvenience and obtaining a pulsatile flow synchronized with a patient with a simple device.

  The above object is achieved by the present invention shown in the following (1) to (5).

  (1) A blood removal tube, a centrifugal pump connected to the blood removal tube, a blood delivery tube, an artificial lung connected to the blood delivery tube, and the blood removal tube In the extracorporeal circulation apparatus having an upstream portion of the centrifugal pump and a bypass blood tube connected to the blood supply blood tube and a downstream portion of the artificial lung, the blood supply blood tube A blood channel cross-sectional area variable means capable of varying the blood channel cross-sectional area in synchronization with the pulsation of the heart is provided downstream of the connection portion between the blood-feeding blood tube and the bypass blood tube. Extracorporeal circulation assist device.

  (2) The apparatus control method according to (1), wherein the blood flow path cross-sectional area is reduced by the blood flow path cross-section varying means during a systole.

  (3) A blood removal tube, a centrifugal pump connected to the blood removal tube, a blood delivery tube, an artificial lung connected to the blood delivery tube, and the blood removal tube An extracorporeal circulation device having an upstream portion of the centrifugal pump and a bypass blood tube connected to the blood-feeding blood tube and the downstream portion of the artificial lung. An extracorporeal circulation assist device comprising blood channel cross-sectional area varying means capable of varying the blood channel cross-sectional area in synchronization with pulsation.

  (4) The device control method according to (3), wherein the blood flow path cross-sectional area is decreased by the blood flow path cross-sectional variable means during diastole.

  (5) The extracorporeal circulation assist device according to any one of (1) to (4), wherein an IABP catheter provided in a blood tube is used as the blood channel cross-sectional area varying means.

  According to the extracorporeal circulation assist device of the present invention, without introducing a new device for clamping the blood tube, avoiding the risk of hemolysis, rotor fatigue of the centrifugal pump, and promotion of plasma leak in the artificial lung, A pulsatile flow synchronized with a patient's heartbeat can be obtained with an existing apparatus, and the load during the systole of the heart can be reduced and the blood flow to the coronary artery can be secured during the diastole.

  Hereinafter, the extracorporeal circulation auxiliary device of the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

  FIG. 1 is a circuit diagram of an extracorporeal circulation assist device according to a first embodiment of the present invention. FIG. 2 is a circuit diagram of the extracorporeal circulation assist device according to the second embodiment of the present invention.

  Hereinafter, the configuration of each unit will be described.

  The extracorporeal circulation assist device 1 includes an extracorporeal circulation circuit 11 and a blood flow path cross-sectional area varying means 12.

  The extracorporeal circuit 11 includes a blood removal blood tube 111 connected to the blood removal catheter 13, a centrifugal pump 112, an artificial lung 114, a blood delivery blood tube 115 connected to the blood delivery catheter 14, and the like. A bypass blood tube 116 is provided between the blood removal blood tube 111 and the blood delivery blood tube 115 via branches 117 and 118, respectively.

  The blood channel cross-sectional area varying means 12 includes an IABP driving device 122 and an IABP catheter 123.

  The IABP catheter 123 is placed in a blood tube. By expanding the balloon 1231 of the IABP catheter 123, the blood flow path cross-sectional area in the blood tube is reduced by being occupied by the balloon 1231, and the amount of blood flowing through the blood tube is reduced.

  Therefore, by repeatedly expanding and contracting the balloon 1231 of the IABP catheter 123 arranged in the blood tube, the blood flow in the blood tube repeatedly decreases and increases.

  As the blood tube used in the present invention, a flexible synthetic resin tube having transparency such as vinyl chloride resin and silicone rubber can be suitably used. A flow meter may be attached to any blood tube. As the flow meter, one that can measure the flow rate of blood flowing inside the blood sending tube without directly contacting the blood is preferable. For example, an ultrasonic flow meter is preferably used.

  The centrifugal pump 12 may be an impeller type, a straight channel type, a cone type, or the like. Further, in the case of a constant pressure type pump, a turbine pump, a screw pump or the like can be used instead of the centrifugal pump.

  The oxygenator 13 may be any type of oxygenator, preferably a membrane oxygenator, and particularly preferably a hollow fiber membrane oxygenator.

  As a hollow fiber membrane oxygenator, a housing, a gas exchange hollow fiber membrane that is a blood processing member inserted in the housing, and both ends of a bundle of hollow fiber membranes are liquid-tightly fixed to both ends of the housing. Gas, which is a blood processing fluid provided in the vicinity of both ends of the partition wall and the housing and communicating with the space (oxygen chamber) formed by the outer surface of the hollow fiber membrane, which is a blood processing member, the inner surface of the housing, and the partition wall And a blood inflow port having a blood inflow port and a blood outflow port having a blood outflow port attached to both ends of the housing, respectively.

  As the hollow fiber bundle housed in the cylindrical housing, a bundle of about 10,000 to 60,000 gas exchange hollow fiber membranes is used. As a gas exchange hollow fiber membrane, Is a porous membrane having a large number of fine pores penetrating therethrough. The hollow fiber membrane for gas exchange has an inner diameter of 100 to 1000 μm, preferably 100 to 300 μm, a wall thickness of 5 to 80 μm, preferably 10 to 60 μm, a porosity of 20 to 80%, preferably 30 to 60%, and a fine pore A pore diameter of 0.01 to 5 μm, preferably about 0.01 to 1 μm is preferably used. Moreover, not only a hollow fiber membrane but a flat membrane shape may be sufficient.

  As the material for the gas exchange hollow fiber membrane, polymer materials such as polypropylene, polyethylene, polytetrafluoroethylene, polysulfone, polyacrylonitrile, cellulose acetate can be used, preferably a hydrophobic polymer, particularly preferably, Polyolefin resin, more preferably polypropylene, and polypropylene having fine pores formed by a stretching method or a phase separation method is desirable.

As the blood channel cross-sectional area varying means 12, IABP used for normal auxiliary circulation
An apparatus can be used suitably.

  The IABP driving device 122 is connected to a connector provided at the proximal end of the IABP catheter 123, and can inhale and discharge fluid (for example, gas such as helium) into the balloon 1231 from the proximal end of the IABP catheter 123. The balloon 1231 is expanded and contracted by the suction and discharge of the fluid.

  The timing of expansion / contraction of the balloon 1231 by the IABP driving device 122 corresponds to the heartbeat detection signal measured by the sensor 121. Specifically, it is preferable that the expansion / contraction timing of the balloon 1231 by the IABP driving device operates in synchronization with the heartbeat detection signal measured by the sensor 121.

  The operation of the extracorporeal circulation assist device of the present invention will be described with reference to FIGS.

  In the embodiment shown in FIG. 1, blood that has been removed from the body through a blood removal catheter 13 that has been inserted from the patient's femoral vein and placed in the vicinity of the right atrium passes through the blood removal blood tube 111, and is centrifuged by a centrifugal pump 112. It is sent to the artificial lung 113.

  In the oxygenator 112, oxygen is added to the blood and carbon dioxide is removed, and then the blood is sent to the patient through the blood-feeding blood tube 115 and the blood-feeding catheter 14 inserted into the femoral artery.

  In this extracorporeal circulation assist device, a blood tube for blood removal 111 and a blood tube for blood delivery 115 are short-circuited by a blood tube for bypass 116. An IABP catheter 123 is inserted through a check valve (not shown) or the like on the downstream side (blood supply side) of the branch 118 of the blood supply blood tube 115 from the bypass blood tube 116.

  The IABP driving device 122 expands and contracts the balloon 1231 by inhaling and discharging helium gas to and from the balloon 1231 of the IABP catheter 123 in synchronization with the heartbeat signal from the sensor 123.

  By inhaling helium gas when the heart is in a systole, the blood flow path cross-sectional area of the blood sending blood tube 115 is reduced. During the diastole of the heart, helium gas is exhausted. As a result, the blood flow delivered to the patient via the blood delivery catheter 14 increases during the diastole of the heart and decreases during the systole of the heart.

  Blood supply from the extracorporeal circulation assist device is a load on the heart because it is a countercurrent to the pumping from the heart during the systole of the heart. By reducing this flow rate during the systole of the heart, it is possible to reduce the burden on the heart in the recovery phase.

  On the other hand, since the extracorporeal circulation assist device secures a sufficient amount of blood supply during the diastole of the heart, it can provide extracorporeal circulation support to the whole body without imposing a burden on the heart, and at the same time increase in coronary blood flow By supplying a sufficient amount of blood during the diastole, sufficient oxygen can be supplied to the myocardium.

  The expansion / contraction of the balloon 1231 is not necessarily the same as the heart rate. For example, the expansion / contraction of the balloon 1231 may be performed about once every 1 to 8 heartbeats. The balloon expansion / contraction cycle per heart rate may be determined according to the degree of recovery of the patient's heart.

  In this method, the blood flow circulating between the bypass blood tube 116 → the centrifugal pump 112 → the artificial lung 114 → the bypass blood tube 116 is maintained even during the period in which the blood supply blood tube 115 is blocked by the balloon 1231. The pressure / flow rate fluctuations in the centrifugal pump 112 and the artificial lung 114 are reduced compared to the conventional method of closing the oxygenator outlet to reduce the amount of blood flow, hemolysis, rotor fatigue of the centrifugal pump, artificial lung The risk of promoting plasma leakage at the site is reduced.

  The embodiment shown in FIG. 2 differs from the embodiment shown in FIG. 1 in the position where the balloon 1231 of the IABP catheter 123 is inserted in the extracorporeal circuit 11.

  In this extracorporeal circulation assist device, the IABP catheter 123 is inserted into the bypass blood tube 116 via a check valve (not shown) or the like.

  Contrary to the case of FIG. 1, the blood flow cross-sectional area of the bypass blood tube 116 is reduced by inhaling helium gas into the balloon 1231 when the heart is in diastole. Helium gas is discharged during the systole of the heart. As a result, the amount of blood that flows through the bypass blood tube 116 and returns to the centrifugal pump 112 increases during the systole of the heart and decreases during the diastole.

  On the other hand, the blood flow rate in the portion downstream of the branching portion 118 of the blood sending blood tube 115 exhibits the opposite behavior to the increase or decrease of the blood volume in the bypass blood tube 116. That is, as in the case of FIG. 1, the blood flow to the patient via the blood delivery catheter 14 increases during the diastole of the heart, and the blood flow decreases during the systole of the heart.

  Even during the period in which the bypass blood tube 116 is blocked by the balloon 1231, the blood flow to the blood sending blood tube is maintained, so that the pressure / flow rate fluctuations in the centrifugal pump 112 and the oxygenator 114 are affected by the outlet of the oxygenator. Compared with the conventional method of reducing the amount of blood flow by blocking the blood flow, the risk of hemolysis, rotor fatigue of a centrifugal pump, and promotion of plasma leakage in an artificial lung is reduced.

  The difference between the first embodiment shown in FIG. 1 and the second embodiment shown in FIG. 2 is the difference in the position where the blood channel cross-sectional area variable means (balloon) is arranged as described above.

  In the case of the embodiment shown in FIG. 1, it is easy to control the amount of blood delivered to the patient, and the balloon 1231 is expanded to the full cross-sectional area of the blood feeding blood tube 115, so that the systolic phase of the patient's heart. In addition, the blood flow from the extracorporeal circulation assist device can be adjusted to zero.

  On the other hand, in the case of the embodiment shown in FIG. 2, even if a thrombus or air bubble caused by the balloon 1231 occurs, it is trapped by the artificial lung on the downstream side, so that there is an advantage that safety is increased.

  The embodiment of the extracorporeal circulation assist device of the present invention has been described above with reference to the illustrated embodiment. However, the present invention is not limited to this embodiment, and each part constituting the extracorporeal circulation assist device can exhibit any similar function. It can be replaced with the configuration of Moreover, arbitrary components may be added.

FIG. 1 is a circuit diagram of an extracorporeal circulation assist device according to a first embodiment of the present invention. FIG. 2 is a circuit diagram of the extracorporeal circulation assist device according to the second embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Extracorporeal circulation assist device 11 Extracorporeal circuit 111 Blood removal tube 112 Centrifugal pump 113 Tube 114 Artificial lung 115 Blood supply blood tube 116 Bypass blood tube 117 Blood removal blood tube branch 118 Blood supply blood tube branch 12 Blood channel cross-sectional area varying means 121 Sensor 122 IABP driving device 123 IABP catheter 1231 Balloon 13 Blood removal catheter 14 Blood delivery catheter

Claims (5)

A blood tube for blood removal, a centrifugal pump connected to the blood tube for blood removal, a blood tube for blood feeding, an artificial lung connected to the blood tube for blood feeding, and the blood tube for blood removal and the centrifuge An extracorporeal circulation apparatus having an upstream portion of a pump and a bypass blood tube connected to the blood-feeding blood tube and a downstream portion of the oxygenator, wherein the blood-feeding blood tube is the blood-feeding tube. An extracorporeal circulation auxiliary device having blood flow path cross-sectional area variable means that can change the cross-sectional area of the blood flow path in synchronism with the pulsation of the heart, downstream of the connecting portion between the blood tube for bypass and the blood tube for bypass apparatus. The apparatus control method according to claim 1, wherein the blood flow path cross-sectional area is decreased by the blood flow path cross-sectional variable means during a systole. A blood tube for blood removal, a centrifugal pump connected to the blood tube for blood removal, a blood tube for blood feeding, an artificial lung connected to the blood tube for blood feeding, and the blood tube for blood removal and the centrifuge In an extracorporeal circulation apparatus having an upstream portion of a pump and a bypass blood tube connected to the blood-feeding blood tube and the downstream portion of the artificial lung, the bypass blood tube is used for pulsation of the heart. An extracorporeal circulation assisting device comprising blood channel cross-sectional area variable means capable of varying the blood channel cross-sectional area in synchronization. The apparatus control method according to claim 3, wherein the blood flow path cross-sectional area is decreased by the blood flow path cross-sectional variable means during diastole. The extracorporeal circulation assist device according to any one of claims 1 to 4, wherein an IABP catheter provided in a blood tube is used as the blood channel cross-sectional area varying means.

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