Retrospective analysis of large bowel obstruction or perforation caused by oral preparation for colonoscopy

Abstract

Background and study aims: Patients undergoing bowel preparation for colonoscopy are at risk of potentially severe adverse events such as large-bowel obstruction (LBO) and perforation. These patients usually need emergency surgery and the consequences may be fatal. Little is known about the risk factors for LBO and perforation in these circumstances. We sought to establish the natural history of LBO and perforation caused by oral preparation for colonoscopy.

Patients and methods: We retrospectively analyzed data from 20 patients with LBO or perforation associated with oral preparation for colonoscopy. All patients were treated at the Showa University Northern Yokohama Hospital (SUNYH) between April 2001 and December 2015. Drugs used for bowel preparation, age, sex, indication for colonoscopy, pathogenesis and treatment were recorded.

Results: Eighteen of the patients had LBO and 2 had perforation. Fourteen events occurred at SUNYH, which accounted for 0.016 % of patients who underwent bowel preparation during this period. Seventeen patients were symptomatic when the decision to undertake colonoscopy was made (including 7 who complained of constipation and 4 who complained of abdominal pain; 3e were asymptomatic). Nineteen patients ultimately required surgery, 13 within 3 days of presentation. Eleven patients ultimately required colostomy. There was no perioperative mortality in our cases.

Conclusion: Large bowel obstruction and perforation are rare events associated with oral preparation for colonoscopy, but frequently require surgery. Exacerbation of constipation might be a risk factor for LBO or perforation. Potentially catastrophic situations can be avoided by early detection and treatment.

Fig. 1

A representative case of a patient with large bowel perforation. The reported symptom at the first hospital visit was narrowing of the stool. There had been defecation on the day of examination. The patient drank 2800 mL polyethylene glycol and defecated 7 times, and subsequently reported sudden-onset abdominal pain and cold sweats. We performed computed tomography and confirmed the presence of free air, ascites and rectal cancer. Emergency surgery was undertaken and at laparotomy, a large amount of intraperitoneal stool was present.

Fig. 2

Strategy for colonoscopy preparation at the Showa University Northern Yokohama Hospital for preventing bowel obstruction and perforation. Caution case means Conservative management and observation. PEG, polyethylene glycol; CT, computed tomography; GE, glycerin enema; LIT, long intestinal tube; SEMS, self-expandable metallic stent.