Tourniquet and tranexamic acid use in total knee arthroplasty

BACKGROUND: There is no consensus on how tourniquet and tranexamic acid (TXA) use in total knee arthroplasty (TKA) affect blood transfusion rates and total blood loss. We compared outcome measures and transfusion rates after TKA, with and without the use of tourniquet and TXA. METHODS: A retrospective study of 477 consecutive patients undergoing primary TKA between 2008 and 2013 was performed. There were 243 in the tourniquet-assisted (TA) and 234 in the tourniquet-unassisted (TU) group. Operative times, hemoglobin levels, blood transfusion rates, complications, and length of stay were assessed. Subanalysis was performed on those patients receiving and not receiving TXA within the TU group. RESULTS: Mean operative duration was 66.4 minutes in the TA group and 87.5 minutes in the TU group (P < .0001). Mean postoperative drop in hemoglobin was greater in TU group (3.1 g/dL vs 2.8 g/dL, P = .002). The transfusion rate was 9.5% in TA compared with 11.5% in TU patients (P = .46) with comparable mean units transfused (2.6 vs 2.2, P = .30). There was no difference in wound infection (P = .82) and total complication rates (P = .27) between groups. Those patients given TXA had a lower hemoglobin drop (2.6 g/dL vs 3.3 g/dL, P = .04) with similar transfusion (13.3% vs 11%, P = .61) and complication (P = .95) rates. CONCLUSIONS: TU TKA had a greater operative duration and postoperative drop in hemoglobin than TA TKA. However, transfusion rates were similar between groups. TXA use reduced the operative decrease in hemoglobin with no effect on complication or transfusion rates. LEVEL OF EVIDENCE: Level III, retrospective cohort study.