Unexpected Hospitalizations and Emergency Room Visits within 30 Days of a Colorectal Cancer Screening-related Colonoscopy Performed at a Canadian Non-hospital Endoscopy Unit

Abstract

Purpose: To determine the rate of and reasons for unexpected emergency room (ER) and inpatient (IP) stays within 30 days of a colorectal cancer (CRC) screening-related colonoscopy in asymptomatic, generally healthy individuals. Methods: All 24,145 colonoscopy appointments from 2008-2010 at the Forzani and MacPhail Colon Cancer Screening Centre, a publicly-funded non-hospital endoscopy unit, were identified from the endoscopy reporting system Endopro, whether or not the colonoscopy was performed. Patients were ASA I/II, free of significant comorbidities. Colonoscopies were performed by one of 51 gastroenterologists or colorectal surgeons. Patients were linked by their personal health number to provincial administrative databases by Alberta Health Services, the government body responsible for providing all emergency and inpatient care in the province of Alberta. All ER and IP visits (events) from two days prior to 30 days after the scheduled date were identified, and research assistants completed reviews of the hospital chart. Severity of the event was classified using a modification of the NHS Bowel Cancer Screening Programme criteria. Causal relationship to the colonoscopy appointment was established by consensus of three of the authors. Results: A total of 22,253 patients (47% men; mean age 56 years; range 17-75) had at least one appointment. Indications for colonoscopy were screening (89%), CRC/adenoma surveillance (5%) and positive FOBT (5%). Overall, 498 events were identified (2.1% of appointments), of which 337 (67%) were not related, 138 (28%) were definitely related and 23 (5%) were possibly related to the appointment; 84% of related events occurred within seven days of the colonoscopy. Thirty events occurred prior to the appointment date, of which six (21%) were definitely or possibly related to the bowel preparation. 21,518 patients underwent 22,054 colonoscopies. Events definitely or possibly related to the colonoscopy occurred in 146 (0.7%), of which 88 (60%) were ER visits with no associated IP stay. There were seven (0.3/1,000) perforations and four (0.2/1,000) post-polypectomy syndromes. There were no colonoscopy-related deaths. Event severity was mild in 107 (72%), intermediate in 33 (22%), and major in nine (6%). The most common colonoscopyrelated events were bleeding (n=63; rate 2.9/1,000) and gastrointestinal symptoms (45; 2.0/1,000). Conclusion: Approximately 2.1% of patients had an ER visit or unexpected IP admission immediately prior to or within 30 days of a scheduled colonoscopy, but most are unrelated to the colonoscopy. Events resulting from a colonoscopy occurred in 0.7%, with bleeding and GI symptoms as the most common causes. The majority of colonoscopy-related events occurred within seven days of the test.