Temporary drainage clamping after total knee arthroplasty: a meta-analysis of randomized controlled trials

Drainage-clamping methods are thought to be effective in reducing blood loss after total knee arthroplasty (TKA). We conducted a systematic review to examine if these methods were effective without increasing the risk of complications. After a comprehensive search, 6 randomized controlled trials involving 603 knees and comparing clamping drainage and the immediate release of the drain after elective TKA were included in this analysis. The results demonstrated that drainage clamping could decrease the volume of drainage, but only clamping for no less than 4 hours could reduce the true blood loss. There was no significant difference between the 2 groups regarding blood transfusion, postoperative range of motion, incidence of thromboembolic events, and wound complications. The current evidence cannot confirm the advantage of clamping drainage after TKA.