Endoluminal Negative-Pressure Therapy for Preventing Rectal Anastomotic Leaks: A Pilot Study in a Pig Model

Background: Anastomotic leak after rectal resection carries substantial morbidity and mortality. A diverting ileostomy is beneficial for high-risk anastomoses, but its creation and reversal carry a surgical risk in addition to that of resection itself. We sought an alternative method for managing complications of rectal anastomosis. Methods: We developed an endoluminal negative-pressure technology with a diverting proximal sump, and hypothesized that it would close anastomotic disruptions in pigs. We performed rectal resections on pigs, with primary anastomoses and the creation of an anastomotic defect. In animals in the treatment group we inserted an endoluminal negative-pressure device and kept it at a low level of continuous suction for 5 d. No device was inserted in a control group of animals. After the 5-d period of treatment we evaluated the anastomoses in both the treatment and control groups of animals for leakage, using contrast enemas. Specimens of anastomosed rectum were evaluated histologically for mucosal integrity and for the location and density of inflammatory responses. Results: Fourteen pigs were assigned to either the treatment (n = 10) or control (n = 4) group. Of the pigs in the treatment group, 90% had complete closure of their rectal defect, as compared with 25% of the animals in the control group (chi(2) test, p = 0.04). The animals in the treatment group had only minimal mucosal and serosal inflammation, whereas those in the control group had extensive mucosal damage with associated serositis. Conclusions: Endoluminal negative-pressure therapy was well-tolerated and led to successful closure of 90% of the anastomic rectal defects in the treatment group of animals in the present study. Additional evaluation of this therapy is warranted.