Clips have been devised for clamping or strangulating various organs, vessels, and other tissue. Clips have been developed for use specifically in strangulating blood vessels in the human body. Such clips are known as hemostatic or ligating clips. The clips may be fabricated from absorbable or nonabsorbable polymeric materials as well as from metal.
A ligating clip is typically C-shaped, U-shaped, or V-shaped with two spaced-apart or diverging legs connected together at one end in a manner that permits the clip to be squeezed together so that the legs of the clip may be clamped around the tissue or blood vessel so as to tightly constrict the tissue or blood vessel. This prevents a substantial amount of fluid from passing through the tissue or blood vessel from one side of the closed clip to the other side of the closed clip.
Typically, the clip is made of a material and/or has a configuration that enables the clip, once it has been forced closed, to remain set or latched and maintain the closed orientation without outside intervention. For example, if the clip is made from a metal material, the clip can be deformed to the closed position. If the clip is made from a thermoplastic material, the legs may be connected by a resilient hinge portion and the distal ends of the legs may be provided with latch means for holding the legs together in a closed position when the legs of the clip are squeezed together around the tissue or blood vessel.
A variety of instruments for applying such surgical clips have been developed or proposed in the past. A number of such instruments are discussed and disclosed in the copending patent application Ser. No. 208,368, filed on Nov. 19, 1980. Such instruments typically include a magazine or cartridge which may or may not be disposable and which holds a plurality of clips. The clips are supplied from the cartridge to jaws of the instrument one at a time for application to the tissue or blood vessel.
U.S. Pat. No. 3,006,344 discloses an instrument for applying a ligating clip to a blood vessel. The clip is formed of flat metal or like stock and has a pair of legs extending outwardly in a generally V-shape. The clips are arranged in two parallel grooves in a magazine. A slide is positioned in each groove and is urged by a suitable conventional spring to advance the clips along the magazine toward the jaws. The clips are arranged in each row with one end of one clip abutting the connecting rear portion of the next adjacent front clip. The clips are not nestably arranged with the connecting portion of each clip received between the open legs of the next adjacent clip. Rather, the distal end of one of the legs of one clip abuts the rear connecting portion of the next adjacent clip.
U.S. Pat. No. 3,753,438 discloses an applicator for applying clips to suturing thread during the suturing of skin wounds. The clips are carried in a cartridge in the instrument. A clip is forced forwardly from the cartridge to a position between the instrument jaws by a slide which is operated by a handle. After the clip is positioned within the jaws, the handles of the instrument are squeezed together to squeeze the clip legs together.
It would be desirable to provide an improved instrument for accommodating a plurality of clips and for automatically feeding the clips seriatim into jaws where the clips may be compressed about tissue, such as blood vessels and the like. It would be beneficial if the clips were contained within a magazine or cartridge and it would be advantageous if the magazine could be easily inserted into, and removed from, the instrument. It would also be beneficial if the instrument could accommodate a magazine of relatively simple design having relatively low material costs and low fabrication costs so that the magazine may be disposable.
It would also be desirable to provide an instrument for applying clips wherein the clips could be arranged in a relatively compact orientation in order to provide an efficient and economical magazine structure. It would be beneficial if the instrument could be provided with means for biasing the clips forwardly from the magazine to the jaws but in a manner that would prevent the clip from being urged or biased against the tissue. This would avoid imposition of an undesired force on the tissue during application of the clip. Further, elimination of a feeding force on the clip during application of the clip would reduce the possibility that the clip might twist or turn during the application of the clip to the tissue. Further, it would also be desirable to eliminate the feeding force on all of the clips in the magazine during the application of the front end clip in the jaws so as to insure that the clips within the magazine are not forced outwardly against the front end clip. This would reduce the possibility that one or more clips might twist or turn at the end of the magazine in the jaw region.
In addition, after a clip has been applied without the undesirable feeding force, it would be beneficial to permit the feeding force to then be re-established on the clips in the magazine. Further, it would be beneficial if the re-establishment of the feeding force could be done in a manner that avoids the imposition of a rapidly applied force or shock loading to the row of clips in the magazine. This would reduce the possibility of the clips being unduly compressed or of the clips twisting in the magazine.
It would also be desirable to provide an instrument for applying ligating clips in which the instrument could be actuated by means of scissors-type handles in the same manner as a number of other widely used surgical instruments and in the manner to which surgeons have become accustomed over the years.