| 摘要 |
<p>A double lumen cannula for applications such as hemodialysis comprises concentric elongated tubular members (12 and 14) for semi-permanent insertion into the subclavian vein of a patient, leaving semi-permanent access thereto for repeated treatments. The outer member (12) has a smooth exterior surface and comprises an elongated main portion (24), a convergent portion (26) and a narrower distal end portion (28). The inner member (14) has a diameter substantially the same as that of the distal end portion and is sealingly engageable with the convergent portion (26), so as to form a continuous inner lumen with the distal end portion (28) of the outer member (12), and is removable therefrom for removal of clot or replacement purposes. Both members are preferably sufficiently flexible to permit curving thereof on a 12 cm radius without reduction in internal cross-section thereof, i.e. without substantial kinking or buckling, so as to avoid constriction of fluid flows.</p> |
