Are staples or sutures the gold standard in gastrointestinal anastomosis? Is a new technique using a compression anastomosis clip addressing the disadvantages of staplers? Does the anastomosis with a compression ring avoid life threatening anastomotic leaks?
Gastrointestinal Anastomosis becomes necessary in procedures that require an excision of a segment of diseased colon or intestine in case of perforation, bleeding, inflammation, or tumor. The transected end portions of the colon require an anastomosis either by opening the peritoneal cavity or with laparoscopic access.
A major challenge is the integrity of the anastomosis in order to avoid the risk of the anastomosis rupturing or leaking into the peritoneal cavity with life threatening contamination and severe postoperative complications. Anastomosis techniques have improved considerably over the past years with the introduction of staplers for mechanical suturing. The advantage of having a reliable anastomosis and saving valuable operating room time compared with manual suturing, have been tainted by the higher cost for the single use stapling devices that need to be stocked in many variations and sizes.
In order to avoid metal staples that remain in place after healing of the anastomosis and to improve the elasticity of the junction, a start-up company has developed a compression ring for anastomosis in the gastrointestinal tract. The device consists of an anastomosis ring shaped in a memory alloy material, and a crimping support element. The memory alloy ring has a circular shape with a central opening and overlapping end portions, that allow for crimping tissue against the crimping support element in order to achieve anastomosis. The crimped bowel eventually becomes ischemic and, within five to fifteen days postoperatively the anastomosis heals. When the anastomosis is complete, both the anastomosis ring and crimping support element are passed through the bowel.
The anastomosis ring is made out of nitinol, a nickel-titanium shape memory alloy that allows a malleable state at lower temperature and an elastic state at higher temperature. When cooled the temperature-sensitive ring opens and after insertion through two small incisions the higher body temperature causes the memory shaped closed position, providing the compression force for the seal of the tissue. The anastomosis clip comes with a hand-held applicator that can be used in hand-assisted laparoscopic applications.
The applicator grips and positions the clip into the two colon segments and has a release mechanism, as well as a tissue cutting function that is associated with the gripping mechanism. The device features a blade and a counter element, which are positioned opposing each other, and designed to mate when closed, effectively perforating the tissue between them. The device cuts through the tissue walls in order to create the predetermined perforation.
Previous attempts of using compression devices for anastomosis had limited success and acceptance due to the technical and material challenges that limited their effectiveness.