Self contained needle and shield

摘要

A surgical needle is disclosed which is made up of two concentric tubes. The inner tube has a sharp tip like a conventional hypodermic or intravenous needle. The inner tube can be retracted into the outer tube after use. In one embodiment, the needle forms part of a catheter assembly. A catheter is mounted coaxially around the both tubes. The inner tube has a latching member attached to the end without the sharp tip. The latching member engages detents on a housing to hold the sharp tip in an extended position or a retracted position. The latching member is provided with a porous plug to assist in venting gases during catheter introduction.