Apparatus and method for regulating tissue welder jaws

Abstract

A surgical apparatus and methods for severing and welding tissue, in particular blood vessels. The apparatus includes an elongated shaft having a pair of relatively movable jaws at a distal end thereof. A first heating element on one of the jaws is adapted to heat up to a first temperature and form a welded region within the tissue, while a second heating element on one of the jaws is adapted to heat up to a second temperature and sever the tissue within the welded region. The first and second heating elements may be provided on the same or opposite jaws. A control handle provided on the proximal end of the elongated shaft includes controls for opening and closing the jaws, and may include an actuator for sending current through the first and second heating elements. The first and second heating elements may be electrically connected in series, and the first heating element may be bifurcated such that it conducts about one half of the current as the second heating element. A force-limiting mechanism provided either within the control handle, in the elongated shaft, or at the jaws limits the pressure applied to the tissue by the jaws to ensure that the tissue is severed and the ends effectively welded within a short amount of time.

1 . A surgical apparatus for welding and severing tissue, comprising:
 first and second relatively movable elongated jaws having facing surfaces;   an elongated shaft having the first and second relatively movable jaws attached to a distal end thereof;   at least one heating element provided on the facing surface of one of the first or second jaws;   a control handle connected to the elongated shaft; a control actuator for alternately separating and bringing together the facing surfaces of the elongated jaws; and   a force-limiting mechanism interposed between the control actuator and the jaws adapted to regulate the magnitude of closing force of the jaws to between about 1-3 lbs (0.45-1.36 kg) to ensure the heating element effectively welds and severs tissue held within the facing surfaces of the closed elongated jaws.   
     
     
         2 - 28 . (canceled)