Abstract: A percutaneous venous catheter includes a first fluid-pervious segment for implantation in the body and a second extravascular segment composed of a flexible tube surrounded by a vapor-barrier sheath. A cuff marks the boundary between the two segments and a connector fitting is mounted to the free end of the extravascular segment, there being a continuous fluid path between the fitting and the tip. The vapor barrier present in the extravascular segment of the catheter prevents fluid transpiration through the catheter wall that tends to draw fluid along the catheter causing an occluding thrombus formation at the catheter tip.

Abstract: A needle or cannula set especially adapted to access an implanted drug delivery portal includes a rigid base having a flat undersurface and a low profile. The base supports one end of a needle so that the needle projects from the base perpendicular to the base undersurface. One end of a flexible tube is secured to the base in fluid communication with the needle and the opposite end of the tube is terminated by a connector. A complaint pad is mounted to the base undersurface to assure proper seating of the base against the skin of the patient when the needle unit is inserted in the patient. The set also includes a handle which releasably connects to the base to facilitate inserting the needle unit into and withdrawing it from the patient and an adhesive dressing which is arranged to drape over the base with its edge margin extending all around the base for anchoring the needle unit to the patient and for providing an occlusive seal all around the puncture site.