The Compression Anastomotic Ring-Locking Procedure: A Novel Technique for Creating a Sutureless Colonic Anastomosis

Background/Aim: Compression anastomoses might represent an improvement over traditional hand-sewn or stapled techniques. Herein, we describe a novel concept of sutureless colonic anastomosis named compression anastomotic ring-locking procedure (CARP). Materials and Methods: The surgical device consists of two anastomotic rings and their associated helping tools, facilitating the placement of the rings into the intestinal ends. Furthermore, four catheters are connected to the surgical device, allowing the evaluation of the anastomosis during and after surgery. A total of 31 pigs underwent a low colocolic anastomosis using the anastomotic rings. The compression pressure was measured perioperatively and up to 96 h after surgery. Anastomotic integrity and morphology were analyzed by use of radiology and histology, respectively. A long-term follow-up was conducted in a subgroup of pigs up to 108 days after surgery when the bursting pressure and stricture formation were examined. Results: All animals recovered uneventfully, and macroscopic examination revealed intact anastomoses without signs of pathological inflammation or adhesions. The perioperative compression pressure was inversely proportional to the gap size between the anastomotic rings. For example, an anastomotic gap of 1.5 mm created a colonic anastomosis with a perioperative compression pressure of 91 mbar, which remained constant for up to 48 h and resulted in a markedly increased compression pressure. Contrast infusion via the catheters effectively visualized the anastomoses, and no leakage was detected within the study. The surgical device was spontaneously evacuated from the intestines within 6 days after surgery. Histology showed collagen bridging of the anastomoses already 72 h after surgery. Long-term follow-up (54-108 days) revealed no stricture formation in the anastomoses, and the bursting pressure ranged from 120 to 235 mbar. The majority of bursts (10/12) occurred distant from the anastomoses. Conclusion: We conclude that the surgical device associated to CARP is safe and efficient for creating colonic anastomoses. Further studies in patients undergoing colorectal surgery are warranted.