Duodenoscope hang time does not correlate with risk of bacterial contamination

•Current guidelines recommend a maximum hang time for duodenoscopes of 5-14 days.•Among 465 cultures, 34 followed a hang time ≥7 days; 431 occurred within 7 days.•The maximum hang time was 40 days; 12 cultures revealed significant contamination.•Prolonged hang time was not associated with a higher likelihood of contamination.

BackgroundCurrent professional guidelines recommend a maximum hang time for reprocessed duodenoscopes of 5-14 days. We sought to study the association between hang time and risk of duodenoscope contamination.MethodsWe analyzed cultures of the elevator mechanism and working channel collected in a highly standardized fashion just before duodenoscope use. Hang time was calculated as the time from reprocessing to duodenoscope sampling. The relationship between hang time and duodenoscope contamination was estimated using a calculated correlation coefficient between hang time in days and degree of contamination on the elevator mechanism and working channel.ResultsThe 18 study duodenoscopes were cultured 531 times, including 465 (87.6%) in the analysis dataset. Hang time ranged from 0.07-39.93 days, including 34 (7.3%) with hang time ≥7.00 days. Twelve cultures (2.6%) demonstrated elevator mechanism and/or working channel contamination. The correlation coefficients for hang time and degree of duodenoscope contamination were very small and not statistically significant (−0.0090 [P = .85] for elevator mechanism and −0.0002 [P = 1.00] for working channel). Odds ratios for hang time (dichotomized at ≥7.00 days) and elevator mechanism and/or working channel contamination were not significant.ConclusionsWe did not find a significant association between hang time and risk of duodenoscope contamination. Future guidelines should consider a recommendation of no limit for hang time.