Changing the patient's position increases number of polyps detected in colonoscopy

In patients undergoing colonoscopy, examining the right side of the colon while the patient lies on the left side increased the detection of polyps and adenomas, compared with examining the patient in the supine position, according to a study published in the September issue of Gastrointestinal Endoscopy.

Polyp detection in the left side of the colon did not improve with patients on their right side, though.

Several recent studies have assessed the merits of positioning patients such that the colon segment being examined is uppermost in the abdomen. The idea is that this should improve luminal distention and increase polyp detection. But results from such investigations have yielded conflicting results.

In this study, researchers included 130 patients, ages 40 to 80, who presented for a diagnostic colonoscopy at Northern General Hospital, in Sheffield, U.K., between March 2012 and February 2014. After intubation, patients were randomized to undergo colonoscopic withdrawal in either the supine position followed by position change, or vice versa. The position change was left lateral position for examination of the right side of the colon and right lateral position for examination of the left side of the colon.

The researchers analyzed their data and determined that examining the right side of the colon with the patient lying on their left side significantly increased the proportion of patients found with one or more polyps (26.2%) and adenomas (17.7%) compared with examination in the supine position (patients found with one or more polyps: 23.1%, adenomas: 16.2%). The number of polyps and adenomas found on the right side of the colon also was greater during withdrawal in the left lateral position.

“Strategies to improve polyp detection in the right side of the colon may be of particular value, given that colonoscopy is reported to offer less protection against right-sided [colorectal cancer],” the authors wrote.

Examining the left side of the colon with the patient lying on their right side, compared with the supine position, did not significantly increase the proportion of patients found with polyps and adenomas.

The researchers also found no significant correlation between luminal distention and polyp detection. This comes as no surprise, they wrote, “because improved visualization does not guarantee identification of additional polyps, and many polyps are visible regardless of luminal distention.”

Most of the additional polyps and adenomas detected after the position change were small and therefore not of immediate clinical significance; however, the authors pointed out that finding more lesions can change the recommendation for how soon the patient should return for the next colonoscopy, which is more effective for ongoing surveillance and prevention.

“Position change during colonoscope withdrawal should be recommended as routine in endoscopic practice,” the researchers concluded.