Self contained gas powered surgical apparatus

A surgical apparatus for driving surgical fasteners comprising:

• a) a frame portion defining an elongated barrel section and a stationary hand grip section which depends angularly from said barrel section;
• b) an elongated body portion extending distally from said barrel section of said frame portion and defining a first longitudinal axis;
• c) a fastener applying assembly associated with a distal end portion of said body portion, said fastener applying assembly including:
• i) a cartridge assembly having a tissue engaging surface thereon and having a plurality of surgical fasteners contained therein;
• and
• ii) an anvil member mounted adjacent said cartridge assembly and having a fastener forming surface thereon, said anvil member and said cartridge assembly being relatively movable between an open position wherein said fastener forming surface is spaced from said tissue engaging surface and a closed position wherein said fastener forming surface is in close cooperative alignment with said tissue engaging surface;
• d) approximation means operatively associated with said fastener applying assembly and actuable from said frame portion for effecting relative movement of said anvil member and said cartridge assembly between said open and closed positions;
• e) fastener ejection means movable through said cartridge assembly and actuable from said frame portion for sequentially ejecting said plurality of surgical fasteners from said cartridge assembly;
• f) a pneumatic actuation system disposed within said frame portion and operatively associated with said means for sequentially ejecting surgical fasteners from said cartridge assembly;
• and
• g) a counter mechanism for indicating the number of times the pneumatic actuation system may be operated, including a ratchet assembly having a linearly translating rack member and a reciprocating ratchet shaft.