1. Field of the Invention
This invention relates to an apparatus for applying a plurality of surgical fasteners to body tissue, and more particularly, to a surgical stapler including a staple cartridge assembly having a lockout mechanism for preventing refiring of the apparatus after the staples have been ejected from the cartridge.
2. Description of the Related Art
Surgical stapling apparatus for simultaneously applying a plurality of surgical fasteners to body tissue are well known in the art. Typically these apparatus include a fastener holder disposed on one side of the tissue to be fastened, an anvil assembly substantially parallel to the fastener holder on the other side of the tissue to be fastened, a mechanism for linearly translating the fastener holder and the anvil assembly toward one another so that the tissue is clamped therebetween, and a mechanism for driving the fasteners from the fastener holder so that the ends of the fasteners pass through the tissue and form finished fasteners as they make contact with the anvil assembly, thereby producing an array of finished fasteners in the tissue.
In common use are devices such as those disclosed in U.S. Pat. Nos. 4,354,628 and 4,665,916. More particularly, U.S. Pat. No. 4,354,628 discloses a surgical stapler apparatus for forming an array of surgical staples in body tissue including an anvil member against which the staplers are crimped, and a staple holder pivotally mounted adjacent one end of the anvil member.
U.S. Pat. No. 4,665,916 discloses a surgical stapling apparatus comprising an anvil assembly against which fasteners are formed and a fastener holder pivotally mounted adjacent one end of the anvil assembly, a spacer member at the other end so constructed to displace tissue that would otherwise obstruct the spacer member from properly positioning the fastener holder relative to the anvil assembly to insure proper fastener formation, and a knife assembly to cut the tissue between the rows of formed fasteners.
In use, a surgeon selects the body tissue to be fastened, positions the instrument so that the tissue is between the anvil assembly and the fastener holder (or cartridge), then actuates the stapler. In some surgical applications, it is necessary to perform several stapling tasks and thus it is not uncommon for a surgeon to replace the cartridge several times during such procedures. In the course of an operation, however, a surgeon or nurse may, inadvertently try to reuse the apparatus with a spent cartridge in the apparatus or select a spent cartridge for placement into the apparatus. In such an instance, operation of the apparatus would be ineffective and would result in a prolongation of the procedure.