Optimal release timing of temporary drain clamping after total knee arthroplasty

Background Bleeding control is critical after total knee arthroplasty (TKA). The purpose of this study was to evaluate the optimal time to release the clamped drain after TKA. Methods We performed unilateral TKA in 120 patients using three methods of drainage. Group A (N = 40) had a 3-hour clamp applied, and group B (N = 40) had a 4-hour clamp applied. Group C (N = 40) underwent conventional negative drainage. We evaluated the drainage volume, as well as the hemodynamic markers, transfusion volume, visual analog scale (VAS) scores, and range of motion (ROM). Results The drained blood volume in groups A and B was significantly less than that in group C. No significant difference was found between groups A and B. The level of hemoglobin in group A was significantly higher than that in group C at 2 days after surgery. The ROM of groups A and C was larger than that of group B at 5 days after surgery. Furthermore, the VAS scores of groups A and C were significantly lower than those of group B at both 2 and 5 days after surgery. Conclusions The temporary drain clamping method after TKA significantly reduced the volume of bleeding and blood transfusion. The 3-h clamping method reduced the drained volume as effectively as the 4-hour clamping method and resulted in less acute phase pain and more rapid recovery of ROM than the 4-hour clamping method. In conclusion, we recommend 3-h clamping after TKA as the optimal release time to reduce blood loss and acute phase pain.