A comparison of three single layer anastomotic techniques in the colon of the rat.

Introduction: Although intestinal anastomoses are mainly made by staplers, manual anastomoses are still in use worldwide. In previous studies, single layer anastomosis has shown better results compared to double layer techniques.

Purpose: To test experimentally some aspects of three different single layer anastomotic techniques in order to identify advantages and disadvantages of each.

Material And Methods: The study was done on Sprague Dawley rats. Animals were randomly divided into four groups. Three experimental groups consisted of 21 animals each, and the fourth sham group contained 10 animals. By 7 animals of each group were sacrificed on the 4th and the rest of 14 animals on the 7th postoperative day. In all groups the resected distal part of the colon was anastomosed using Halsted, Gambee and Gambee-Halsted technique. To evaluate each specific technique the following were used: postoperative complication frequency, biomechanical measurements, adhesion density, condition of intestinal lumen and histological parameters of the healing process.

Results: The complication frequency was not significantly different between the tested techniques. The average bursting pressure and tensile strength were higher on both the 4th and 7th postoperative days with the Gambee technique. In the colon segments removed on the 4th postoperative day 97% of pressure induced ruptures occurred in the anastomotic line, whereas on the 7th postoperative day 76% of ruptures occurred about 1cm distal to the anastomotic line.

Conclusion: The Gambee technique had significantly better biomechanical and histological results compare to the other two anastomotic techniques. Adhesion density was significantly lower in the control group (p<0.001).