Evaluation of the biofragmentable anastomotic ring following preoperative irradiation to the rectosigmoid in dogs

An animal study was done to evaluate the safety of a sutureless colorectal anastomosis in irradiated bowel. Forty mongrel dogs received preoperative radiation with 5000 rads and then underwent a low anterior resection and anastomosis using either the EEA-31TM stapling device, a two-layer handsewn technique, or the biofragmentable anastomotic ring (BAR) 31-1.5 mm and BAR 31-2.0 mm devices. The anastomoses were then evaluated for early and late anastomotic healing and leaks. The results show four radiographic (three clinical) leaks (P less than .05) in the BAR 31-1.5 mm group and one radiographic leak in the handsewn group. No leaks were detected in the EEA or BAR 31-2.0 mm groups. Results indicate that all three techniques can be done safely with this dose of radiation, and gap size (1.5 mm vs. 2.0 mm) is of critical importance when performing a BAR anastomosis in irradiated bowel.

Biofragmentable bowel anastomosis ring: comparative efficacy studies in dogs

Three studies were conducted in a total of 178 dogs to determine the efficacy of a biofragmentable bowel anastomosis ring (BAR) composed of polyglycolic acid and 12.5% barium sulfate. Wound strength and healing of BAR, suture, and staple colonic anastomoses were compared for intervals of up to 1 year. The effect of systemic steroid treatment and BAR size on anastomotic wound strength and healing was also studied. The BARs fragmented at a mean time of 15.06 days postoperatively and were passed in the feces without injury. Wound strength was determined by measurements of the pressure required to burst the anastomosed colonic segment and measurements of the tension required to break 10 mm wide longitudinal strips of the anastomosed segment. The studies demonstrated that wound strength had progressed to a point where continued mechanical support (with sutures or staples) was no longer required by 14 days in both nontreated and steroid-treated dogs. Gross healing evaluations at 21 days and beyond showed no differences due to anastomotic method. Microscopic evaluations suggested that residual granulation tissue was less at the sites of BAR asastomoses than at sites of suture or staple anastomoses at the 1-year interval, suggesting that healing may be better with BAR than with standard methods of colon anastomosis.

Initial clinical experience with a biofragmentable ring for sutureless bowel anastomosis

Twenty-seven patients have had bowel anastomoses with a biofragmentable ring for sutureless bowel anastomosis. There were no complications associated with the anastomotic technique. One patient developed an ischemic stricture on the proximal side of the anastomosis due to compromised circulation. There was no leakage. Technical factors regarding the BAR anastomosis are described. A properly placed purse-string suture is of primary importance. Advantages appear to be a more rapid and easy anastomosis with better healing.

A biofragmentable ring for sutureless bowel anastomosis. An experimental study

A biofragmentable bowel anastomosis ring (BAR) for sutureless intestinal anastomosis is described with the laboratory results comparing the BAR to sutured and stapled anastomoses. There was equivalent healing with all three methods of anastomosis. However, "burst" pressure was highest at day zero and overall necrosis was least with the BAR. By virtue of these findings and being sutureless, it is hoped that the limits of safe bowel anastomosis can be extended.