Carbon dioxide insufflation compared with air insufflation in double-balloon enteroscopy: a prospective, randomized, double-blind trial

Background: Few studies have evaluated the degree of pain, the amount of retained gas, and the safety of carbon dioxide (CO(2)) insufflation in patients undergoing double-balloon enteroscopy (DBE). Objective: To clarify the usefulness and safety of CO(2) installation during DBE. Design: Single-center, prospective, randomized, double-blind, controlled trial. Setting: University hospital. Patients: Forty eligible patients with small-bowel disease for whom DBE was indicated were randomized to a CO(2) installation (CO(2)) group or an air installation (air) group by means of sealed envelopes. Intervention: DBE with insufflation of CO(2) or air. Main Outcome Measurements: Efficacy evaluation was based on the degree of pain as assessed by use of a visual analog scale (VAS) and the amount of residual gas retention within the small and large bowels on radiography. The safety of CO(2) installation was evaluated by arterial blood gas analysis. Results: Significantly fewer patients in the CO(2) group had severe pain of >= 50 mm on the VAS during DBE than in the air group (P = .02). Significantly less gas was retained in the small bowel just after and at 3 hours after DBE in the CO(2) group than in the air group (P = .003, P = .01, respectively). There was significantly less residual gas retention in the large bowel at 3 hours after DBE in the CO(2) group than in the air group (P = .02). There was no significant difference in pre-DBE and post-DBE partial pressure of oxygen in the blood (PaO(2)) and partial pressure of carbon dioxide in the blood (PaCO(2)) between groups. Limitations: Small sample size. Conclusion: CO(2) insufflation is a safe and useful procedure when performed during DBE. (Gastrointest Endosc 2011,73:743-9.)