Cannula

• US 5,314,418 A
• Filed: 09/09/1993
• Issued: 05/24/1994
• Est. Priority Date: 09/21/1990
• Status: Expired due to Fees

• Current Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Original Assignee: Toyoda Gosei Company Limited (Toyota Motor Corporation)
• Inventors: Kimura, Takashi, Kashiwabara, Susumu, Sasaki, Eisaku, Takano, Hisateru, Nakatani, Takeshi, Taenaka, Yoshiyuki
• Primary Examiner(s): Yasko, John D.
• Assistant Examiner(s): MENDEZ, MANUEL A
• Application Number:
  US08/118,281
• Time in Patent Office: 257 Days
• Field of Search: 604/280-282, 604/164, 604/264, 604/170, 604/95, 128/656-658, 128/772
• US Class Current: 604/540
• CPC Class Codes: A61M 1/3659 Cannulae pertaining to extracorporeal circulation
• CPC Class Codes: A61M 25/0052 Localized reinforcement, e.g. where only a specific part of the catheter is reinforced, for rapid exchange guidewire port
• CPC Class Codes: A61M 25/0054 with regions for increasing flexibility
• CPC Class Codes: A61M 60/113 in other functional devices, e.g. dialysers or heart-lung machines
• CPC Class Codes: A61M 60/232 Centrifugal pumps
• CPC Class Codes: A61M 60/279 Peristaltic pumps, e.g. roller pumps
• CPC Class Codes: A61M 60/38 Blood oxygenation

Abstract

There is disclosed a draining cannula to be connected with the left atrium which comprises a tip portion (A), a curvature portion (B) connected with said tip portion and a body tubular portion (C) connected with said curvature portion. The length and the outer diameter of said cannula is sufficient for inserting the cannula into the femoral vein and for reaching the tip portion the left atrium passing through the cava, the right atrium and the interatrial septum. The portion (B) is made of a material which is more flexible than that of said portion (C). A resilient spiral thin wire is provided within the thickenss of the wall part defining the lumen of the curvature portion (B). The cannula is used for draining from the left atrium by inserting it into the femoral vein and passing the tip portion (A) of said cannula through the cava, the right atrium and the interatrial septum to reach the left atrium, without thoracotomy.

Claims

1. A cannula which comprises a tip portion (A), a curvature portion (B) connected with said tip portion and a body tubular portion (C) connected with said curvature portion, said cannula having a lumen longitudinally extending through the tip portion, the curvature portion and the body tubular portion;

the length and the outer diameter of said cannula being, at least, 300 mm and, at most, 12 mm, respectively;

the length of said tip portion (A) and said curvature portion (B) being 10 to 50 mm and 20 to 100 mm, respectively;

said curvature portion (B) being made of a material which is more flexible than that of said body tubular portion (C);

a resilient spiral thin wire provided within the thickness of the wall part defining the lumen of said curvature portion (B) and extending over, at least, 20 mm in length of said curvature portion (B);

wherein said cannula is adapted to be inserted into the femoral vein with the tip portion (A) passing through the cava, the right atrium and the interatrial septum to reach the left atrium, for draining from the left atrium without thoracotomy; and

wherein the material of the curvature portion (B) has a Shore hardness of 45A to 65D and the body tubular portion (C) has a Shore hardness of 90A to 75D.

2. A cannula according to claim 1, wherein the length of the cannula is 400 to 700 mm and the outer diameter of the cannula is 5 to 10 mm.

3. A method for assisting blood circulation which comprises draining a blood from the left atrium by a cannula a cannula having a tip portion (A), a curvature portion (B) connected with said tip curvature portion, said cannula having a lumen longitudinally extending through the tip portion, the curvature portion and the body tubular portion;

the length and the outer diameter of said cannula being, at least, 300 mm and, at most, 12 mm, respectively;

the length of said tip portion (A) and said curvature portion (B) being 10 to 50 mm and 20 to 100 mm, respectively;

said curvature portion (B) being made of a material which is more flexible than that of said body tubular portion (C);

a resilient spiral thin wire provided within the thickness of the wall part defining the lumen of said curvature portion (B) and extending over, at least, 20 mm in length of said curvature portion (B);

inserting said cannula into the femoral vein with the tip portion (A) of said cannula passing through the cava, the right atrium and the interatrial septum to reach the left atrium for draining there from, without thoracotomy; and

draining blood being perfused to the femoral artery by a femoral arterial cannula.

4. A method for draining from the left atrium which comprises inserting a cannula having a tip portion (A), a curvature portion (B) connected with said tip portion and a body tubular portion (C) connected with said curvature portion into the femoral vein, and passing the tip portion (A) of said cannula through the cava, the right atrium and the interatrial septum to reach the left atrium, without thoracotomy, said cannula having a lumen longitudinally extending through the tip portion, the curvature portion and the body tubular portion;

the length and the outer diameter of said cannula being, at least, 300 mm and, at most, 12 mm, respectively;

the length of said tip portion (A) and said curvature portion (B) being 10 to 50 mm and 20 to 1090 mm, respectively;

said curvature portion (B) being made of a material which is more flexible than that of said body tubular portion (C); and

a resilient spiral thin wire provided within the thickness of the wall part defining the lumen of said curvature portion (B) and extending over, at least, 20 mm in length of said curvature portion (B).