Randomized trial of standard versus magnetic endoscope imaging colonoscopes for unsedated colonoscopy

Background: Unsedated colonoscopy has potential benefits, including decreased costs and decreased risks.

Objective: To determine whether patient comfort during unsedated colonoscopy can be improved through the use of a magnetic endoscopic imaging (MEI) colonoscope compared with a standard colonoscope.

Design: Prospective, patient-blinded, randomized, controlled trial.

Setting: San Francisco Veterans Affairs Medical Center.

Patients: Veterans undergoing outpatient screening or surveillance colonoscopy.

Interventions: Use of a standard or MEI colonoscope during unsedated colonoscopy.

Main outcome measurement: The primary outcome variable was patient perception of pain using a 7-point scale. The secondary endpoint was patient willingness to undergo a future unsedated colonoscopy.

Results: Of the 160 patients enrolled, 140 completed an unsedated colonoscopy in the study protocol. In a per-protocol analysis, the mean and median pain score was 3.12 (standard deviation 1.22) and 4 (interquartile range 2-4) for the standard colonoscope group and 3.06 (standard deviation 1.13) and 3 (interquartile range 2-4) for the MEI group, where 3 was mild pain (P = not significant). Overall, 80% of subjects were willing to undergo a future unsedated colonoscopy for screening or surveillance. In an intention-to-treat analysis, 80% of subjects (64/80) in the standard colonoscope arm and 79% in the MEI arm (63/80) were willing to undergo a future unsedated colonoscopy (P = not significant).

Limitations: Single-center study of mostly male veterans.

Conclusions: This patient-blinded, randomized, controlled trial did not demonstrate any difference in patient perception of pain or willingness to undergo unsedated examinations when using the MEI versus the conventional colonoscope. Unsedated colonoscopy is generally feasible and well tolerated and is associated with high patient satisfaction rates.