| 摘要 |
An especially designed double lumen catheter (10) for use in a device for in-vivo purification of blood, by means of which blood pumped out of a vein is subjected to intensive ultrafiltration and the retentate, together with a quantity of a substitute fluid roughly coresponding, volumetrically, to the filtrate, is returned to the vein. The double lumen catheter (10) with a coaxial arrangement of the two catheter tubes (13,14) is so designed that the outer tube (14) is shorter than the inner tube (13) which latter forms the open catheter tip (12). The inner tube (13) is 4-6 cm longer than the outer tube (14) and, beginning from the tip (12), it has 4 pairs of lateral openings (11) at mutual spacings of between 8 and 12 mm. The outer tube (14) at its end has, over a length of 3.5-6 cm, 4 pairs of lateral openings (11) at a spacing of 8-12 mm each and at the smooth transition from the outer tube (14) to the inner tube (13) there is provided a contrast ring (15), of a material which under X-ray radiation is detectable through contrast formation. At the other end of the catheter (10) the inner tube (13) is made longer than the outer tube (14), for the connection of a two-way connecting member. |
