157. RESULTS OF A GLOBAL BLOOD-SPARING STRATEGY FOR TOTAL KNEE ARTHROPLASTY

Abstract

Purpose of the study: The risk of homologous blood transfusion for primary total knee arthroplasty (TKA) varies between centres from 4 to 72%. Measurement of mean blood loss for patients undergoing primary total hip or knee arthroplasty led us to adopt a global blood-sparing protocol.

Material and methods: This was a prospective observational study involving 90 TKA (TC-SB) implanted by one surgeon in 56 women and 33 men, mean age 74 years, ASA 3 for 29%, mean BMI=31. Programmed autologous transfusion and blood recovery were not applied. Alpha epoeitine (EPO was administered in the preoperative period in accordance with the predicted serum haemoglobin at discharge. Tranexamic acid (TA) was injected intravenously during the operation.

Results: The mean operative time was 63 minutes, mean tourniquet time 51 minutes. During the perioperatively period, the mean 7-day blood loss was 566±254 ml red cells and 1560±643 total blood. Mean serum haemoglobin at discharge was 1.0 g/dl. Fourteen percent of patients had a postoperative serum haemoglobin less than 10 g/dl (lowest level 8.4 g/dl). One patient had a transfusion; this was a man in his nineties who was operated on without a tourniquet and without TA because of a poor arterial system. Nearly 86% of patients received TA with a significant (p< 0.05) decrease in bleeding compared with those who did not receive TA (365 ml total blood). EPO was delivered for 22% of patients (2.8 injections on average) to reached 14.2 g/dl the day before the operation.

Discussion: This overall strategy for blood sparing enabled us to reduce the risk of transfusion and limit costs. In this series, the prescription of EPO was not targeted to reach a set level preoperatively but was based on the predicted serum haemoglobin level at discharge. Thus seven patients with a preoperative haematocrit below 39 did not receive EPO. None of these patients were transfused. Their discharge haemoglobin was between 10.7 and 12.4g/dl. Use of TA should be included in the calculation of the predicted discharge haemoglobin level in order to better determine candidates for EPO injections.