Sicherheitstrokar

摘要

A safety trocar instrument, for piercing the wall of an anatomical cavity to provide communication with the inside of the cavity, includes a tubular cannula and an elongate trocar having a sharp piercing point. The 2trocar is mounted for axial reciprocal movement within the cannula. In a withdrawn rest position, the point is received within and shielded by the distal end of the cannula. A retraction spring biases the trocar to its withdrawn position.