Abstract: We included six trials randomising 359 participants, 178 to T-tube drainage and 181 to primary closure. All trials were at high risk of bias. There was no significant difference in mortality between the two groups (4/178 (weighted percentage 1.2%) in the T-tube group versus 1/181 (0.6%) in the primary closure group; RR 2.25; 95% CI 0.55 to 9.25; six trials). There was no significant difference in the serious morbidity rate between the two groups (24/136 (weighted serious morbidity rate, 145 events per 1000 patients) in the T-tube group versus 9/136 (weighted serious morbidity rate, 66 events per 1000 patients) in the primary closure group; RaR 2.19; 95% CI 0.98 to 4.91; four trials). Quality of life and return to work were not reported in any of the trials. The operating time was significantly longer in the T-tube drainage group compared with the primary closure group (MD 28.90 minutes; 95% CI 17.18 to 40.62 minutes; one trial). The hospital stay was significantly longer in the T-tube drainage group compared with the primary closure group (MD 4.72 days; 95% CI 0.83 days to 8.60 days; five trials). T-tube drainage appeared to result in significantly longer operating time and hospital stay compared with primary closure without any apparent evidence of benefit on clinically important outcomes after open common bile duct exploration. Based on the currently available evidence, there is no justification for the routine use of T-tube drainage after open common bile duct exploration in patients with common bile duct stones. T-tube drainage should not be used outside well designed randomised clinical trials. More randomised trials comparing the effects of T-tube drainage versus primary closure after open common bile duct exploration may be needed. Such trials should be conducted with low risk of bias and assessing the long-term beneficial and harmful effects of T-tube drainage, including long-term complications such as bile stricture and recurrence of common bile duct stones.

Plain-language summary: We identified a total of six trials including 359 participants of whom 178 had primary closure and 181 patients had T-tube drainage after open exploration of the common bile duct. All six trials were at high risk of bias (risk of overestimating the benefits and underestimating the harms of the intervention or the control). There was no significant difference in mortality (12 deaths per 1000 participants in the T-tube drainage group versus 6 deaths per 1000 participants in the primary closure group) or in the serious complication rate after surgery between the two groups (approximately 145 complications per 1000 participants in the T-tube drainage group versus 66 complications per 1000 participants in the primary closure group). Although the number of deaths and complication rates in the primary closure group appeared to be less than half those in the T-tube group, there is a possibility that this was not a true observation but rather a difference that occurred by chance (similar to there being one chance in eight of flipping a coin and having it come up heads or tails three times in a row). For this reason we cannot be sufficiently confident that a true effect exists, and we term such a difference as not being statistically significant. None of the trials reported quality of life or the time taken for patients to return to work. The average operating time was significantly longer in the T-tube drainage group than in the primary closure group (by about 30 minutes). The average hospital stay was significantly longer in the T-tube group than in the primary closure group (by about five days). Use of a T-tube appears to increase the cost without providing any benefit to the patients. Further randomised trials with low risk of bias (low chance of arriving at the wrong conclusions because of prejudice by healthcare providers, researchers, or patients) and low risk of random errors (arriving at wrong conclusions because of chance) are necessary to confirm whether the use of T-tubes is justified anymore. Until the results from such trials are available, we discourage the routine use of T-tube after open common bile duct exploration.