Predictors of utilization of early colonoscopy vs. radiography for severe lower intestinal bleeding

The management of acute lower intestinal bleeding is not standardized. This study assessed factors associated with early (within 24 hours of presentation) colonoscopy vs. radiographic evaluation of patients with severe acute lower intestinal bleeding in routine practice.

A cohort of 252 patients admitted with acute lower intestinal bleeding to a teaching hospital (August 1996 to June 1999) was studied retrospectively. Severe bleeding was defined as transfusion of two units of packed red blood cells and/or a greater than 20% decrease in hematocrit within 24 hours of presentation. If both colonoscopy and radiography were performed, the initial procedure was analyzed. Multivariable regression was used to identify independent factors related to each of the two initial interventions.

A total of 118 patients met criteria for severe bleeding; 33 (28%) underwent an initial, early colonoscopy and 20 (17%) underwent an initial, early radiographic procedure (17 radionuclide scintigraphy, 3 angiography). Independent factors related to early colonoscopy were post-polypectomy bleeding (OR 6.3: 95% CI[1.4, 28.0]), admission on a weekday (OR 3.0: 95% CI[1.0, 8.6]), and admission late in the day (OR 2.7: 95% CI[1.0, 7.0]). Independent factors related to early radiography were tachycardia (OR 5.1: 95% CI[1.7, 14.9]), syncope (OR 3.8: 95% CI[1.1, 13.2]) and bleeding during the first 4 hours after admission (OR 3.1: 95% CI[1.0, 9.0]). Colonoscopy was associated with shorter hospital stay (p=0.025), increased diagnostic yield (p=0.005), and fewer red blood cell transfusions (p=0.024). Rates of therapeutic intervention, surgery, and death did not differ significantly between the two strategies.

Logistical factors and the likelihood of a localized source of bleeding influence the performance of early colonoscopy for the evaluation of acute lower intestinal bleeding, whereas patients with clinical indicators of severe bleeding often undergo radiographic procedures. Because early colonoscopy may improve outcomes, further studies are needed to compare available strategies and to standardize the management of acute lower intestinal bleeding.