Blood transfusion after Primary Total Knee Arthroplasty in Hong Kong: retrospective review of 11,914 patients

Abstract

Introduction: The reported rate of allogeneic blood transfusions (ABT) after primary total knee arthroplasty (TKA) was around 10% in centres with blood-conservative policy. This study aimed to review the ABT rate after primary TKA in public hospitals in Hong Kong. Methods: Data on the number of primary TKA performed, the number of patients who had ABT, and the numbers of unit given after TKA in the period between 2004 to 2012 were retrospectively retrieved from an electronic database in the Hospital Authority and were analysed. Results: Among 11,914 patients in the 15 hospitals, the mean (± standard deviation) rate of ABT after primary TKA and the mean number of units given per transfusion episode were 34.6 ± 0.02% (range, 31.7-37.5%) and 2.0 ± 0.1 units, respectively. The mean rate of ABT ranged from 9.6 to 54.2% (± 0.12%) in the hospitals studied. From the regression analysis, there was a statistically significant linear relationship between the number of primary TKA performed and total unit of ABT given annually (R2 = 0.96, y = 0.67 + 35.71). Discussion and Conclusion: Our study showed the ABT rate after TKA remained static around 35%, which was higher than that in hospitals with blood conservative policies. The old belief, transfusing 2 units of blood if transfusion necessary, is still held in our practice. Our study also identified wide-ranging rates of ABT across the hospitals, suggesting that there is room for improvement in our current perioperative blood management policy in TKA.