BIDIRECTIONAL VALVED CATHETER

摘要

A valved catheter (10) having an elongated, flexible tubular element (18) defining a lumen (20) extending along an axis substantially parallel to the central axis (A) of said tubular element, and a bidirectional check valve assembly (12) near its distal end (16) which controls fluid flow in the tubular element. The valve assembly includes an aspiration valve (24) offset from the tip of the distal end of the tubular element and an infusion valve (26) formed at the tip of the distal end of the element. The aspiration valve is generally defined by one or more ports (24', 24") in the tubular element and a sleeve (30) within the tubular element underlying the ports, where the sleeve normally closes the ports. The aspiration valve (24) permits fluid flow from the patient's bloodstream into the tubular element (18) when the static fluid pressure inside the tubular element distal end (16) is lower than the static fluid pressure outside the aspiration valve by an amount sufficient to displace the sleeve (30) to allow fluid flow through the ports. The infusion valve (26) includes a throat (42) formed in the tubular element distal end (16) which tapers down to a mouth (44) formed by jaws (or "lips") (48, 48') at the tip of the tubular element. The mouth (44) is essentially closed to fluid inflow from the patient into the tubular element and normally closed to fluid outflow from the tubular element into the patient. The infusion valve (26) permits fluid infusion into the patient's bloodstream when the static fluid pressure inside of the tubular element distal end (16) is higher than the static fluid pressure outside of the infusion valve (26) by an amount sufficient to force the mouth (44) open. A bidirectionally valved mutiple lumen catheter (10') is also disclosed.