Several studies have shown that using carbon dioxide (CO2) rather than room air to distend the colon during endoscopy can reduce patient pain and discomfort, yet most colonoscopies performed worldwide still use room air insufflation. The authors of an article published in Annals of Internal Medicine discuss the potential reasons why physicians have been slow to adopt the technology.

Millions of patients undergo colonoscopy every year. During the procedure, air is pumped into the patient's bowel through the endoscope so that the physician can get a clear view of the gastrointestinal tract. Room air is poorly absorbed from the colon, so endoscopists suction air during instrument withdrawal. Still, substantial amounts of air remain in the colon. Natural release takes hours to days with patients frequently experiencing symptoms such as pain, discomfort, and anal leakage.

CO2 is absorbed from the colon 160 times faster than nitrogen and 12 times faster than oxygen. When CO2 is used instead of room air, patients experience reduced pain, less anal leakage, faster recovery, and significantly reduced need for nurse attention post-procedure. So why aren't physicians adopting this technology? For one, standard endoscopy equipment comes with air insufflation pumps and insufflation of CO2 would require an add-on purchase of a small box for the endoscopy rack called a CO2 insufflator. While the device is simple to use and very inexpensive, it does not generate much revenue. In addition, CO2 insufflation is not mentioned in guidelines and does not generate the excitement or interest associated with new "high-tech" endoscopic technology. And finally, since patient pain and discomfort is considered a minor problem associated with colonoscopy, there is little interest in changing the procedure. The authors hope that the current era of patient engagement and shared decision making will motivate change in endoscopy.

Article DOI: 10.7326/M16-0209, Annals of Internal Medicine. Published online Monday 9 May 2016. Note: Full reference information not provided to MNT pre-embargo.