Autologous re-transfusion drain compared with no drain in total knee arthroplasty:a randomised controlled trial

Background. Post-operative anaemia following total knee arthroplasty is reported to impede functional mobility in the early period following surgery, whereas allogeneic blood transfusions, used to correct low post-operative haemoglobin levels, have concomitant disadvantages. The use of a post-operative autologous blood re-transfusion drainage system as well as no drainage system following total knee arthroplasty have been shown to reduce pen-operative blood loss and allogeneic blood transfusions, compared to the regularly used closed-suction drains. No randomised studies have been performed, to the best of our knowledge, that indicate the superiority of either method.Materials and methods. An open, randomised controlled study was conducted in 115 patients undergoing total knee arthroplasty who were randomly allocated to an autotransfusion drain or no drainage system. The primary end-point was haemoglobin level on the first post-operative day.Results. In the autotransfusion group 515 mL (0-1,500 mL) of drained blood was re-transfused within the first 6 hours after surgery. Haemoglobin levels on the first (11.6 vs 11.0 g/dL), second (11.0 vs 10.3 g/dL) and third (10.5 vs 9.8 g/dL) days after surgery were significantly higher in the autotransfusion group. Total pen-operative net blood loss (1,576 mL vs 1,837 mL; P=0.03) and allogeneic transfusion rates (10.2% vs 19.6%; P=0.15) were lower in the autotransfusion group. There were no differences in pain scores, range of motion or adverse events during hospital stay and the first 3 months after surgery.Discussion. Compared with no drainage, the use of a post-operative autologous blood re-transfusion drainage system following total knee arthroplasty results in higher post-operative haemoglobin levels and less total blood loss.