Prone positioning of obese patients for colonoscopy results in shortened cecal intubation times: a randomized trial

Obesity is a risk factor for colorectal cancer, and colonoscopy can be technically challenging in obese patients. It has been proposed (with little supporting data) that prone positioning of obese patients might facilitate a difficult colonoscopy.

The aim of this study was to determine if starting colonoscopy in the prone position for obese patients decreases cecal intubation times.

This was a prospective, randomized study conducted at the North Texas VA Medical Center. Patients with a body mass index of ≥30 kg/m(2) undergoing elective colonoscopy were randomized 1:1 to either initial prone positioning or standard, left-lateral positioning. The outcome measurements were cecal intubation time, frequency of repositioning, sedative medications used, reports of pain, complications, and procedure tolerability.

Fifty patients were randomized to have colonoscopy starting in the standard, left-lateral decubitus position, and 51 to the prone position. The average cecal intubation time for the standard group was 550 vs. 424 s in the prone group (p = 0.03). Patient repositioning was used in 28 % of patients in the standard group versus 8 % in the prone group (p = 0.009). There was no difference in subjective reports of pain between groups (p = 0.95) or in average pain scores (p = 0.79). Follow-up interviews were conducted in 93 % of patients, all of whom said that they would be willing to have repeat colonoscopy in the same position.

Performance of colonoscopy in the prone position for obese patients results in significantly shorter cecal intubation times and decreased need for patient repositioning. Prone positioning is well accepted and does not significantly increase procedure-related discomfort.