More on Withdrawal Time in Colonoscopy
Douglas K. Rex, MD, MASGE, reviewing Desai M, et al. Gastrointest Endosc 2022 Oct 10.
Current recommendations are that minimum withdrawal times in screening colonoscopy that are negative should average at least 6 minutes.
In an analysis of a previously published prospective randomized trial in 3 centers in the U.S., investigators measured the effect of withdrawal time on adenoma detection rate (ADR). Rather than simple withdrawal time, the study evaluated inspection time, which is the withdrawal time minus any time for washing and cleaning or removal of polyps.
Among 1142 patients, 46% underwent screening and 54% underwent surveillance colonoscopy. The median withdrawal time was 9.0 minutes in the screening group and 9.3 minutes in the surveillance group, and ADRs were 49.6% and 63.9%, respectively.
When investigators segregated withdrawal time into 1-minute increments, ADR increased as withdrawal time increased from 6 to 13 minutes, with a ceiling effect at 13 minutes and a 6% increase per minute in the likelihood of detecting an additional patient with at least 1 adenoma (P=.004). The serrated detection rate leveled off at 10 minutes.
Although the incremental effect at 1-minute intervals leveled off at 13 minutes, there was still some positive impact on ADR for withdrawal times of 13 minutes or longer versus less than 13 minutes.
![d-rex](/wp-content/uploads/d-rex.jpg)
COMMENTWe’ve now seen multiple studies showing that withdrawal times longer than 6 minutes are beneficial even though most evidence has suggested that improvements in detection of adenomas and serrated lesions, as well as cancer prevention, level off at 8 to 9 minutes. It seems likely that future recommendations on the technical performance quality of colonoscopy will recommend a longer mean withdrawal time.
Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.
CITATION(S)
Desai M, Rex DK, Bohm ME, et al. Impact of withdrawal time on adenoma detection rate: results from a prospective, multi-center trial. Gastrointest Endosc 2022 Oct 10. (Epub ahead of print) (https://doi.org/10.1016/j.gie.2022.09.031)