Preoperative predictors for allogenic blood transfusion in hip and knee arthroplasty for rheumatoid arthritis.

INTRODUCTION: To identify the preoperative predictors of requirement for postoperative allogenic blood transfusion following hip and knee joint arthroplasty.
MATERIALS AND METHODS: We analysed the retrospective data on patients with rheumatoid arthritis who had undergone either total hip or knee arthroplasty at a single university teaching hospital. Factors of age, sex, procedure type, preoperative haemoglobin, blood transfusion data, comorbidities and body mass index were investigated for association with postoperative allogenic blood after hip or knee arthroplasty.
RESULTS: Three hundred and forty nine cases of patients with rheumatoid arthritis were reviewed. 21 % (n = 72) required allogenic blood transfusion. The only significant predictive preoperative factors associated with postoperative blood transfusion were a low preoperative haemoglobin (Hb) level (p < 0.001), procedure of total hip arthroplasty (p = 0.008), a previous history of myocardial infarction (p = 0.038) and previous allogenic blood transfusion (p = 0.03). A preoperative haemoglobin <120 g/l was associated with a tenfold increase in transfusion requirement. All patients with a preoperative Hb level <90 g/l were transfused.
CONCLUSIONS: The ability to identify those within this high-risk group who are likely to receive blood transfusion allows for an informed, appropriate and cost effective approach to blood management strategies.