Improvement of colonic healing by preoperative oral partially hydrolyzed guar gum (Benefiber) in rats which underwent preoperative radiotherapy

Background: Neoadjuvant radiotherapy in rectal cancer could interfere with anastomotic healing. We investigated the effects of preoperative oral administration of Benefiber on the healing irradiated colonic anastomosis. Methods: Forty male Wistar rats were divided into four groups. Group I (control group), Group II (Benefiber (R) pretreatment group), Group III (preoperative radiotherapy group) and Group IV (preoperative radiotherapy and Benefiber (R) pretreatment group). All animals underwent 1 cm left colon resection and primary anastomosis. On the 3rd and 7th postoperative days, all the rats were anesthetized to assess the anastomotic healing clinically, mechanically, histologically and biochemically. Results: The mean bursting pressure was significantly lower in-group III and significantly higher in-group II on day 7. The histologic parameters of anastomotic healing, such as epithelial regeneration and formation of granulation tissue, were significantly improved by use of preoperative Benefiber (R) on day 7. The amount of acid-soluble collagen concentrations significantly increased in-group IV compared to group III on day 3. The amount of salt-soluble collagen concentrations significantly increased in group II compared to group III on day 3. Conclusions: Colonic anastomotic healing can be adversely affected by preoperative radiotherapy, but orogastric feeding with Benefiber may improve the healing process.