JP2011083421A - Cannula for blood removal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase efficiency of an extracorporeal circulation by inhibiting the suction of blood in a right atrium in removing blood from an ascending vena cava and a descending vena cava during the extracorporeal circulation. <P>SOLUTION: A cannula 1 for a blood removal includes a tubular portion 10 inserted from one side to the other side of the ascending vena cava and the descending vena cava. In the tubular portion 10, blood removal openings 10c, 10d opened respectively in the ascending vena cava and the descending vena cava are formed. An occlusion portion 11 for occluding the side of the right atrium of the ascending vena cava is formed on the side of a proximal end relative to the blood removal opening 10c of the tubular portion 10. An occluding portion 12 for occluding the side of the right atrium of the descending vena cava is formed on the side of a proximal end side relative to the occluding portion 11 of the tubular portion 10. The blood in the ascending vena cava and the descending vena cava is removed by the blood removal openings 10c, 10d while the ascending vena cava and the descending vena cava are occluded by the occluding portions 11, 12. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a blood removal cannula for use in extracorporeal circulation of patient blood.

  Conventionally, when circulating a patient's blood extracorporeally, a blood removal cannula for extracting blood from the body and a blood feeding cannula for sending blood to the body (hereinafter also referred to as blood return) are used. . A blood removal hole is formed at the distal end side in the insertion direction of the blood removal cannula, while the proximal end side is connected to an extracorporeal circulation device (see, for example, Patent Documents 1 and 2).

JP 2003-700 A JP 2003-38650 A

  By the way, there are cases of intractable hypoxemia as a case of pulmonary dysfunction that does not recover even after treatment with a ventilator or the like and cannot use a ventilator. In such cases, when there is no heart failure and a self-beat can be secured, it is conceivable to perform extracorporeal lung assist (ECLA) for the purpose of assisting the lung. Extracorporeal lung assistance is performed using an oxygenator, a blood removal cannula, a blood delivery cannula, etc., and blood is removed from the vein and returned to the artery, so-called VA bypass method, and blood removal from the vein. Then, there is a so-called VV bypass method for returning blood to the vein.

  In the VA bypass method, blood is generally returned to the femoral artery and right axillary artery, but even if oxygen-rich blood is sent to these arteries, they are separated from the coronary arteries of the heart. There is a possibility that the oxygen supply amount to the heart is insufficient, and there is a concern that the oxygen supply amount to the brain is insufficient. On the other hand, in the VV bypass method, oxygen-rich blood is flowed from the vein to the right atrium, returned from the lungs to the left ventricle, and sent from the left ventricle to the whole body in the same way as normal blood flow by self-beat. Therefore, it is an advantageous method in that blood containing a lot of oxygen can also flow into the coronary arteries and the brain, and a sufficient amount of oxygen can be secured.

  However, in the VV bypass method, both the blood removal cannula and the blood delivery cannula are inserted into the vein, so that both cannulas approach each other. For this reason, blood containing a lot of oxygen that has just been sent from the blood sending cannula is sucked into the blood removal cannula, and as a result, a sufficient supply amount of blood containing a lot of oxygen cannot be secured. .

  Therefore, a method is conceivable in which blood is removed from the central side (right atrium side) of the ascending vena cava and the descending vena cava and sent to the right atrium. Hypoxic blood flows through the whole body and returns to the right atrium on the central side of the ascending and descending vena cava. By using this method, hypoxic blood is efficiently removed. Blood can be removed. Then, oxygen can be included in the blood that has been removed by the oxygenator, and the blood can be returned directly to the right atrium, thereby increasing the amount of blood that contains a large amount of oxygen.

  However, since the central sides of the ascending and descending vena cava are close to the right atrium, blood removal is possible even when the blood is removed from the ascending and descending vena cava and returned to the right atrium. It is inevitable that the cannula for blood supply and the cannula for blood transfer are close to each other. Therefore, even with this method, blood that has just been returned to the right atrium from the blood sending cannula may be inhaled into the blood removal cannula, which may reduce the efficiency of lung assistance.

  The present invention has been made in view of such points, and the object of the present invention is to inhale blood in the right atrium when blood is removed from the central side of the ascending and descending vena cava, respectively. Is to increase the efficiency of extracorporeal circulation.

  In order to achieve the above object, in the present invention, the right atrium side of the ascending vena cava and the right atrium side of the descending vena cava are respectively occluded so as to be partitioned from the right atrium, and the blood removal hole is formed in the ascending vena cava and the descending aorta. Each was opened into a vein.

  Specifically, in the first invention, a blood removal cannula for removing blood from the ascending vena cava and the descending vena cava during extracorporeal circulation of blood, wherein the ascending vena cava and the descending vena cava from one side to the other A tube portion having first and second blood removal holes inserted in the ascending vena cava and the descending vena cava, respectively, and closer to the second blood removal hole than the first blood removal hole of the tube portion Provided between the first occlusion portion for occluding the right atrial side of the ascending vena cava and the second blood removal hole and the first occlusion portion of the tube portion, and to the right of the descending vena cava It is set as the structure provided with the 2nd obstruction | occlusion part for obstruct | occluding the atrial side.

  According to this configuration, when the tube portion is inserted into the ascending vena cava and the descending vena cava, the first and second blood removal holes are located in the ascending vena cava and the descending vena cava, respectively. Then, the right atrium side of the ascending vena cava is blocked by the first occlusion portion, and the right atrium side of the descending vena cava is blocked by the second occlusion portion. As a result, the right atrium is partitioned from the ascending vena cava and the descending vena cava. Therefore, blood in the ascending vena cava is inhaled from the first blood removal hole, blood in the descending vena cava is inhaled from the second blood removal hole, and blood in the right atrium is in the first and second blood removal holes. It becomes difficult to be inhaled from.

  In a second invention, in the first invention, the first and second closing portions are configured by an expansion member that expands by supplying a fluid, and a fluid supply device is connected to the expansion member. .

  According to this configuration, it is easy to insert the tube portion into the ascending vena cava and the descending vena cava by removing fluid from the first and second occlusion portions and contracting both occlusion portions. Then, after insertion, fluid is supplied to the first and second occluded portions by the fluid supply device to expand the occluded portions, so that the ascending vena cava and the descending vena cava are reliably occluded.

  According to a third invention, in the second invention, the first connection pipe for connecting the first closing part and the fluid supplier, and the second connection pipe for connecting the second closing part and the fluid supplier, A fluid is separately supplied to the first and second connection pipes.

  According to this configuration, for example, the second occlusion portion is inflated to occlude the descending vena cava, and then the first occlusion portion is inflated to occlude the ascending vena cava, or vice versa. It becomes possible to occlude.

  According to the first invention, the first and second blood removal holes in the tube portion are closed in a state where the right atrial side of the ascending vena cava and the right atrium side of the descending vena cava are respectively occluded by the first and second occlusion portions. It can be located in the ascending vena cava and the descending vena cava, respectively. As a result, blood in each vena cava can be reliably removed while preventing blood in the right atrium from being inhaled from the first and second blood removal holes, thereby improving the efficiency of extracorporeal circulation. it can.

  According to the second invention, since the first and second occlusion portions are constituted by the expansion members that are expanded by the supply of fluid, the both vena cavas can be inserted while facilitating the insertion procedure into the ascending vena cava and the descending vena cava. It can be reliably occluded.

  According to the third aspect of the invention, the timing for closing the ascending vena cava and the descending vena cava can be changed according to the patient's condition and procedure and can be closed at an appropriate timing.

It is a side view of the cannula for blood removal which concerns on embodiment. It is a figure explaining the extracorporeal type lung assistance. It is sectional drawing of the heart and the vascular system which show the state which inserted the cannula for blood sending, and the cannula for blood removal. FIG. 2 is a view corresponding to FIG. 1 in a state where the SVC blocking portion and the IVC blocking portion are expanded. It is the VV sectional view taken on the line in FIG. FIG. 4 is a view corresponding to FIG. 3 in a state where the IVC closing portion is expanded. FIG. 4 is a view corresponding to FIG. 3 in a state where the descending vena cava is occluded by the IVC occlusion portion. FIG. 4 is a view corresponding to FIG. 3 in a state in which the ascending vena cava is blocked by the SVC block.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature and is not intended to limit the present invention, its application, or its use.

  FIG. 1 shows a blood removal cannula 1 according to an embodiment of the present invention. As shown in FIG. 2, the blood removal cannula 1 constitutes an external lung assisting device 103 together with an oxygenator 100, a blood feeding cannula 101, and a blood pump 102, as shown in FIG. Is. This extracorporeal pulmonary assist device 103 is configured to perform SVC / IVC blood removal RA blood feeding method for blood removal from the ascending vena cava SVC and descending vena cava IVC and returning to the right atrium RA. Yes.

  In the description of this embodiment, the anatomy of the heart H will be described based on FIG. 3 before the structure of the blood removal cannula 1 is described. A pulmonary vein PVe is connected to the left atrium LA. There is a mitral valve MV between the left atrium LA and the left ventricle LV. There is an aortic valve AV in front of the mitral valve MV, and the left ventricle LV is connected to the ascending aorta AAo via the aortic valve AV. On the other hand, the ascending vena cava SVC and the descending vena cava IVC are connected to the right atrium RA, and there is a tricuspid valve TV between the right atrium RA and the right ventricle RV. A pulmonary valve PVa is located in front of the aortic valve AV, and the right ventricle RV is connected to the pulmonary artery PA via the pulmonary valve PVa.

  Next, the structure of the blood removal cannula 1 will be described. The blood removal cannula 1 includes a tube portion 10 through which blood flows, an SVC occlusion portion 11 for occluding the ascending vena cava SVC, an IVC occlusion portion 12 for occluding the descending vena cava IVC, and an SVC occlusion. First and second air pumps 13 and 14 for supplying air to the part 11 and the IVC closing part 12, a first connection pipe 15 connecting the SVC closing part 11 and the first air pump 13, and an IVC And a second connecting pipe 16 for connecting the closing portion 12 and the second air pump 14.

  The tube part 10 is made of a resin material having flexibility, the thickness is set to 18 Fr (French) or more and 21 Fr or less, and the length of the insertion part 10 a inserted into the body is set to 450 mm or more and 550 mm or less. Has been. If the thickness of the tube part 10 is made thinner than 18 Fr, a sufficient blood flow rate will not be secured, and if it is made thicker than 24 Fr, the insertion procedure into the vein becomes difficult, so the blood flow rate and the ease of the insertion procedure are taken into consideration. The above range is set.

  The above numerical values are those used for extracorporeal circulation in adults. For example, when used for children, the numerical values may be smaller and shorter than the above, and are limited to the above numerical values. is not.

  A connector 10b is provided on the proximal end side of the insertion portion 10a of the tube portion 10. As shown in FIG. 2, a tube 100a extending from the oxygenator 100 is connected to the connector 10b.

  As shown in FIG. 1, the tube portion 10 includes four SVC blood removal holes (first blood removal holes) 10c, 10c,... For blood removal from the ascending vena cava SVC, and the descending vena cava. There are eight IVC blood removal holes (second blood removal holes) 10b, 10b,... For blood removal from the IVC. The SVC blood removal holes 10c, 10c,... And the IVC blood removal holes 10b, 10b,... Are separated in the longitudinal direction of the tube portion 10 corresponding to the separation distance between the ascending vena cava SVC and the descending vena cava IVC. Yes. Specifically, the SVC blood removal holes 10c, 10c,... Are separated from each other in the longitudinal direction of the tube portion 10 and in the circumferential direction. It is about 20 mm away from the distal end of the portion 10 to the proximal end side. Similarly, the IVC blood removal holes 10d, 10d,... Are separated from each other in the longitudinal direction of the tube portion 10 and in the circumferential direction, and the IVC blood removal hole 10d located at the most distal end is the distal end of the tube portion 10. From about 300 mm to 400 mm.

  The numbers and positions of the SVC blood removal holes 10c and the IVC blood removal holes 10d are not limited to the above, and can be freely set.

  As shown in FIG. 4, the SVC blocking portion 11 is a balloon-like member composed of an inflating member that inflates when air is supplied, and is made of a known flexible resin material. The SVC blocking portion 11 is positioned on the proximal side of the SVC blood removal hole 10 c of the tube portion 10 and is continuous over the entire circumference of the tube portion 10. When air is extracted from the SVC blocking portion 11, as shown in FIG. 1, the tube portion 10 contracts until there is almost no step. On the other hand, if air is supplied, it will expand | swell so that it may protrude to radial direction from the outer peripheral surface of the pipe part 10 over the perimeter as shown in FIG. The outer diameter at the time of expansion of the SVC blocking portion 11 can be arbitrarily adjusted by the supply amount of air, and expands to such an extent that it is in close contact with the inner wall of the ascending vena cava SVC over the entire circumference.

  The IVC occlusion portion 12 is similarly configured with the same member as the SVC occlusion portion 11 and is close to the IVC blood removal hole 10d between the SVC occlusion portion 11 of the tube portion 10 and the IVC blood removal hole 10d. It is located in the part of. Note that the shapes of the SVC blocking portion 11 and the IVC blocking portion 12 may be different.

  The first air pump 13 is configured to discharge air when operated by an operator, and is provided with a check valve (not shown) that prevents air from flowing on the opposite side to the discharge direction. Of the structure. By operating the check valve, the air in the SVC closing part 11 can be discharged.

  One end of the first connection pipe 15 is connected to the discharge port of the first air pump 13, and the other end communicates with the inside of the SVC blocking part 11. The first air pump 13 side of the first connection pipe 15 extends toward the connector 10b side outside the insertion portion 10a. Therefore, the 1st air pump 13 comes to be located in the connector 10b vicinity. Further, the SVC closing portion 11 side of the first connecting pipe 15 is introduced into the insertion portion 10a from between the connector 10b and the insertion portion 10a to a portion corresponding to the SVC closing portion 11 toward the distal end side. It extends (see FIG. 5).

  The second air pump 14 is the same as the first air pump 13. One end of the second connecting pipe 16 is connected to the discharge port of the second air pump 14, and the other end is connected to the IVC blocking portion 12. The first connection pipe 15 and the second connection pipe 16 are separated from each other in the circumferential direction of the pipe portion 10.

  The first air pump 13 and the second air pump 14 are marked to prevent confusion. In addition, confusion can also be prevented by changing the color of the 1st air pump 13 and the 2nd air pump 14, or changing a shape.

  Next, a case where extracorporeal lung assistance is performed using the blood removal cannula 1 configured as described above will be described.

  First, the connector 10b of the blood removal cannula 1 is connected to the end portion of the tube 100a extending from the oxygenator 100, and it is confirmed whether air is extracted from the SVC occlusion portion 11 and the IVC occlusion portion 12.

  Next, as shown in FIG. 2 and FIG. 3, the blood sending cannula 101 is inserted from the right internal jugular vein into the ascending vena cava SVC to reach the right atrium RA.

  Thereafter, the blood removal cannula 1 is inserted from the right femoral vein into the descending vena cava IVC and the ascending vena cava SVC, and the insertion is stopped when the IVC occlusion portion 12 reaches the right atrium RA. At this time, since the SVC blocking portion 11 and the IVC blocking portion 12 are contracted, they are not disturbed and can be easily inserted.

  Then, as shown in FIG. 6, the second air pump 14 is operated to supply air to the IVC closing portion 12, and the IVC closing portion 12 is expanded. When the outer diameter of the IVC occlusion portion 12 is larger than the inner diameter of the central end of the descending vena cava IVC, the supply of air is stopped. The air supply stop timing can be easily set by grasping the relationship between the air supply amount and the outer diameter of the IVC blocking portion 12 before insertion.

  After the IVC occlusion portion 12 is expanded in the right atrium RA, the blood removal cannula 1 is pulled in the pulling direction. Then, as shown in FIG. 7, the IVC occlusion portion 12 is fitted to the central end of the descending vena cava IVC, and thereby the descending vena cava IVC is occluded from the right atrial RA side. As described above, since the IVC occlusion portion 12 is expanded in the right atrium RA, it is difficult for the IVC occlusion portion 12 to enter deeper toward the distal side of the descending vena cava IVC. Thereby, it is possible to prevent the opening of the hepatic vein A extending from the distal side from the central end of the descending vena cava IVC from being blocked by the IVC blocking portion 12.

  Thereafter, as shown in FIG. 8, the second air pump 14 is operated to inflate the SVC occlusion portion 11 in the same manner as the IVC occlusion portion 12, thereby bringing the SVC occlusion portion 11 into close contact with the inner wall of the ascending vena cava SVC. . As a result, the ascending vena cava SVC is blocked from the right atrial RA side. Thus, since the SVC occlusion part 11 and the IVC occlusion part 12 can be separately inflated, the SVC occlusion part 11 and the IVC occlusion part 12 can be securely connected to the ascending vena cava SVC and the descending vena cava IVC. It can be inflated until it can be closed.

  As described above, the right atrium RA is partitioned from the ascending vena cava SVC and the descending vena cava IVC. Accordingly, blood in the ascending vena cava SVC is inhaled from the SVC blood removal hole 10c, blood in the descending vena cava IVC is inhaled from the IVC blood removal hole 10d, and blood in the right atrium RA is removed from the SVC. Since it becomes difficult to be inhaled from the blood hole 10c and the IVC blood removal hole 10d, the blood returned from the blood cannula 101 to the right atrium RA is not removed.

  As described above, by using the blood removal cannula 1 according to this embodiment, blood in the right atrium RA returned from the blood supply cannula 101 is sucked into the blood removal holes 10c and 10d. Since the blood in the ascending vena cava SVC and the descending vena cava IVC can be surely removed while suppressing the above, the efficiency of extracorporeal circulation can be increased.

  In addition, since the SVC occlusion portion 11 and the IVC occlusion portion 12 are formed of an inflating member, it is possible to reliably occlude both the vena cava SVC and IVC while facilitating insertion into the ascending vena cava SVC and the descending vena cava IVC. it can.

  In addition, since the SVC occlusion part 11 and the IVC occlusion part 12 are separately inflated, the timing for occluding the ascending vena cava SVC and the descending vena cava IVC is changed according to the patient's condition and procedure. It is possible to close at a proper timing.

  In the above embodiment, the first and second air pumps 13 and 14 are used to manually inflate the SVC closing portion 11 and the IVC closing portion 12. It is also possible to automatically expand and contract using an air pump or the like.

  In addition to air, for example, physiological saline may be supplied to the SVC block 11 and the IVC block 12.

  The blood removal cannula 1 may be inserted from the ascending vena cava SVC toward the descending vena cava IVC.

  The blood removal cannula 1 can be used by being connected to a heart-lung machine.

  As described above, the blood removal cannula according to the present invention can be used, for example, when performing extracorporeal lung assistance.

DESCRIPTION OF SYMBOLS 1 Blood removal cannula 10 Tube part 10c SVC blood removal hole (1st blood removal hole)
10d IVC blood removal hole (second blood removal hole)
11 SVC blocking part (first blocking part)
12 IVC blockage (second blockage)
13 First air pump (fluid supply)
14 Second air pump (fluid supply)
15 First connection tube 16 Second connection tube 100 Artificial lung device 101 Blood cannula RA Right atrium SVC Ascending vena cava IVC Ascending vena cava

Claims (3)

A blood removal cannula for blood removal from the ascending and descending vena cava during extracorporeal circulation of blood,
A tube having first and second blood removal holes inserted from one side of the ascending vena cava and the descending vena cava to the other side and opening into the ascending vena cava and the descending vena cava, respectively;
A first occlusion portion provided in a portion closer to the second blood removal hole than the first blood removal hole of the tube portion, for closing the right atrium side of the ascending vena cava;
A blood removal device comprising: a second occlusion portion provided between the second blood removal hole and the first occlusion portion of the tube portion, for occlusion of the right atrium side of the descending vena cava Cannula. The blood removal cannula of claim 1,
The first and second blocking portions are configured by an expansion member that expands by supplying a fluid,
A blood removal cannula, wherein a fluid supplier is connected to the expansion member. The blood removal cannula according to claim 2,
A first connecting pipe connecting the first closing part and the fluid supply;
A second connecting pipe for connecting the second blocking portion and the fluid supply unit;
A blood removal cannula, wherein fluid is separately supplied to the first and second connection pipes.

Images