Objective: Our objective was to evaluate the safety of lower endoscopy after colonic surgery, which has been unstudied and unknown. Endoscopy could promote suture breakdown at sites of colonic anastomoses, ostia, or repair by colonic abrasion or stretch from endoscopic intubation, torque, and insufflation.
Methods: Risks versus benefits of lower endoscopy performed within 3 wk of colonic surgery were retrospectively analyzed at five medical centers in 36 patients undergoing sigmoidoscopy and 72 age-and-sex-matched controls, and in 16 patients undergoing colonoscopy and 32 age-and-sex-matched controls.
Results: Sigmoidoscopy indications included rectal bleeding in 14, distal colonic obstruction in 12, and other in 10. Sigmoidoscopy provided the diagnosis in 18 (54%) of 33 cases (excluding three therapeutic sigmoidoscopies, control rate = 30%, p < 0.01, X2, including colon cancer in six and benign stricture in five. Sigmoidoscopy led to colonic surgery in nine and medical therapy changes in four. Colonoscopy indications included colonic bleeding in seven, colonic obstruction in five, and other in four. Colonoscopy provided the diagnosis in nine (56%, control rate = 56%, NS, X2). Colonoscopy led to colonic surgery in three and chemotherapy in one. Two endoscopic complications, unrelated to suture breakdown, occurred: An acutely ill patient developed hypotension during sigmoidoscopy which resolved with intravenous fluid resuscitation. A contained sigmoid diverticular perforation became a free perforation (requiring laparotomy) after colonoscopy. Both control groups had no endoscopic complications (NS, Fisher's exact test).
Conclusion: In this study, the benefits outweighed the risks of postoperative sigmoidoscopy and colonoscopy. Clinicians should use discretion and perform colonoscopy or sigmoidoscopy after colonic surgery, particularly bowel anastomosis, only for clinically important indications. Endoscopy is contraindicated when colonic wound dehiscence or bowel perforation is suspected.