Reduction of blood transfusion rates in unilateral total knee arthroplasty by the introduction of a simple blood transfusion protocol.

We prospectively studied blood transfusion practices within a single institution before and after the introduction of a blood transfusion protocol in consecutive patients undergoing unilateral total knee arthroplasty. Data were collected on 393 patients (group I) prior to and 295 patients (group II) after the introduction of the protocol. Following the introduction of the protocol, patients with preoperative haemoglobin of less than 11 g/dl were cross-matched prior to surgery. The criterion for postoperative transfusion was postoperative haemoglobin of less than 8.5 g/dl or a symptomatic patient with haemoglobin of greater than 8.5 g/dl. This change in practice reduced the transfusion rates from 31% in group I to 11.9% in group II. It reduced the non-utilisation of blood from 64 to 1%. There were no adverse outcomes related to the introduction of the protocol.