August 20, 2015
2 min read

Colonoscopy polyp detection rate increases in right side of colon when patient position changed during withdrawal

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A randomized controlled trial demonstrated that during colonoscope withdrawal, examining patients in the left lateral position increased polyp detection in the right side of the colon compared with examining patients in the supine position.

Because previous data on the benefits of position change during colonoscope withdrawal are conflicting, researchers performed a randomized, two-way crossover study of 130 patients aged 40 to 80 years who underwent diagnostic colonoscopy at the Northern General Hospital, Sheffield, UK, from March 2012 to February 2014.

Each colon segment was examined twice during colonoscope withdrawal, and the primary outcome measure was polyp detection rate for each segment. Patients were randomly assigned to undergo colonoscope withdrawal starting in the supine position followed by a position change (left lateral position for the right side of the colon; right lateral position for the left side) or vice versa, and the transverse colon was examined twice in the supine position.

The investigators observed that when the right side of the colon was examined in the left lateral rather than the supine position, the proportion of patients with at least one polyp detected increased from 17.7% to 26.2% (P = .009), the proportion of patients with at least one adenoma detected increased from 16.2% vs. 23.1% (P = .025), and the mean number of polyps and adenomas detected per patient increased from 0.24 ± 0.6 to 0.32 ± 0.6 (P = .008) and from 0.22 ± 0.6 to 0.29 ± 0.6 (P = .02), respectively. Conversely, polyp detection did not change significantly with position in the left side of the colon, nor did it change during the first and second withdrawal through the transverse colon.

Adequate luminal distension also increased with position change in the right (46% vs. 76%; P < .0001) and left sides of the colon (58% vs. 92%; P < .0001), though there was no significant correlation with polyp detection. Using the position change strategy would have changed surveillance interval recommendation in ten patients.

“In summary, we have shown that examining the right side of the colon with the patient in the left lateral position during colonoscope withdrawal is associated with increased luminal distension and greater polyp and adenoma detection,” the researchers concluded. “This is complementary to previous studies that report that the optimal position to examine the transverse colon is the supine position. Position change appears to be less important in the left side of the colon, but we advocate its use when views are suboptimal. Position change during colonoscope withdrawal should be recommended as routine in endoscopic practice.” – by Adam Leitenberger

Disclosure: The researchers report no relevant financial disclosures.