Catheter needle assembly with enclosable needle

Abstract

Methods and devices to facilitate positioning of a catheter into a vessel. Devices include axially concentric assemblies of a piercing cannula, a shield and tubing such as a catheter where the shield can be passively or actively locked into position over the cannula tip to prevent inadvertent needle sticks.

1 . (canceled) 
     
     
         2 . A medical assembly comprising:
 a cannula extending from a cannula hub to a cannula distal end;   a shield member extending from a shield hub to a shield distal end, the shield member positioned over the cannula and comprising a seat and a locking arm, the seat configured to receive a tubing hub, and the locking arm comprising a fixed portion and a free portion, where the free portion is biased away from the shield hub;   a tubing extending from the tubing hub to a tubing distal end, the tubing positioned over the shield member; and   wherein in a first configuration the free portion engages a surface feature of the tubing hub causing the shield hub to be releasably locked to the tubing hub.   
     
     
         3 . The medical assembly of  claim 2 , wherein opposite relative movement between the cannula hub and the shield hub positions the cannula distal end within the shield member to produce a protected position. 
     
     
         4 . The medical assembly of  claim 2 , wherein separation of the shield hub and the tubing hub causes the locking arm to engage the cannula hub causing locking together of the cannula hub and the shield hub. 
     
     
         5 . The medical assembly of  claim 2 , wherein the locking arm further comprises one or more locking surfaces. 
     
     
         6 . The medical assembly of  claim 2 , wherein the locking arm further comprises one or more guide surfaces. 
     
     
         7 . The medical assembly of  claim 2 , wherein the locking arm further comprises an opening configured to allow movement of the shield member within the cannula hub. 
     
     
         8 . The medical assembly of  claim 2 , wherein the locking arm further comprises a living hinge. 
     
     
         9 . The medical assembly of  claim 2 , wherein the locking arm further comprises a joining surface configured to provide support for the locking arm. 
     
     
         10 . The medical assembly of  claim 2 , wherein the shield distal end further comprises a tapered distal portion. 
     
     
         11 . A medical assembly, comprising:
 a cannula extending from a cannula hub to a cannula distal end;   a shield member extending from a shield hub to a shield distal end, the shield member positioned over the cannula and comprising a locking arm, the locking arm comprising a fixed portion and a free portion, where the free portion is biased away from the shield hub;   a tubing extending from a tubing hub to a tubing distal end, the tubing positioned over the shield member; and   a valve in fluid communication with the tubing hub, the valve comprising a barrier layer at a distal end of the valve, the barrier layer comprising one or more slits and a wall portion extending proximally from the barrier layer defining a valve cavity.   
     
     
         12 . The medical assembly of  claim 11 , wherein the valve further comprises a flange portion formed around the wall portion, wherein the flange portion comprises a diameter greater than that of the wall portion. 
     
     
         13 . The medical assembly of  claim 11 , wherein the barrier layer further comprises a plurality of leaflet structures. 
     
     
         14 . The medical assembly of  claim 11 , wherein the valve is affixed to the catheter hub at the wall portion. 
     
     
         15 . The medical assembly of  claim 12 , wherein the valve is affixed to the catheter hub at the flange portion. 
     
     
         16 . The medical assembly of  claim 12 , wherein the flange portion encircles the valve. 
     
     
         17 . The medical assembly of  claim 12 , wherein the flange portion further comprises openings such that the flange portion is not circumferentially continuous about the wall.