A pneumatic motorized surgical stapler (10), comprising: a frame (12)； an elongated member (30) fixed to the frame； a set of tools (100) that can be attached to the distal end of the elongate member, said set of tools including an anvil assembly and a cartridge assembly, each having a coupling surface of the opposite tissue, said cartridge including a plurality of surgical staples； a drive assembly (520) that can be selectively activated, which includes a drive shaft (521), said drive shaft being mechanically coupled with a drive spindle (555), such that with the selective activation of said drive assembly, said drive shaft rotates said feed spindle to advance a trigger shaft and drive said set of tools to initially muzzle the tissue between opposite tissue coupling surfaces of said set of tools, and to subsequently force a firing piston (578) in said set of tools to deform the surgical clips and fix the tissue, characterized by a pressure sensitive trigger (580), which regulates the speed of the drive assembly which, in turn regulates the speed at which said surgical clips are deformed.Una grapadora quirúrgica (10) motorizada neumáticamente, que comprende: un armazón (12)； un miembro alargado (30) fijado al armazón； un conjunto de herramientas (100) que se puede fijar al extremo distal del miembro alargado, incluyendo dicho conjunto de herramientas un conjunto de yunque y un conjunto de cartucho, teniendo cada uno una superficie de acople del tejido opuesta, incluyendo dicho cartucho una pluralidad de grapas quirúrgicas； un conjunto motriz (520) que se puede activar selectivamente, que incluye un eje (521) de accionamiento, estando dicho eje de accionamiento acoplado mecánicamente con un husillo de avance (555), tal que con la activación selectiva de dicho conjunto motriz, dicho eje de accionamiento gira dicho husillo de avance para hacer avanzar un eje de disparo y accionar dicho conjunto de herramientas para amordazar inicialmente el tejido entre las superficies
