Surgical stapling device for performing circular anastomoses

摘要

This application is directed to a surgical stapling device for performing circular anastomoses. The surgical stapling device includes a handle portion, an elongated body portion and a head portion including an anvil assembly and a shell assembly. The handle portion includes a rotatable approximation knob for approximating the anvil and shell assemblies and a firing trigger for actuating a firing mechanism for ejecting staples positioned within the shell assembly. The firing trigger forms one link of a two bar linkage provided to actuate the firing mechanism. The anvil assembly includes a tiltable anvil which will tilt automatically after firing of the device and unapproximating the anvil and shell assemblies. The head portion also includes a retractable trocar assembly which is slidably positioned within an anvil retainer and is automatically advanced and retracted upon attachment and detachment of the anvil assembly onto the anvil retainer. A lockout tube is provided and is positioned about an anvil retainer for releasably engaging an anvil assembly. The lockout tube prevents inadvertent detachment of the anvil assembly from the anvil retainer. The surgical stapling device also includes a firing lockout assembly which prevents actuation of the firing trigger until an anvil has been attached to the device and the anvil has been approximated. In one preferred embodiment, the firing lockout assembly includes a trigger lock and a safety bracket which prevents movement of the trigger lock from a locked to an unlocked position until an anvil has been attached to the device and approximated and returns the trigger lock to a locked position after the device has been fired. A tactile indication mechanism is also provided for notifying a surgeon that the device has been fired and for notifying a surgeon that the anvil head has been unapproximated a distance sufficient to permit the anvil head to tilt.