Analysis of transfusion predictors in shoulder arthroplasty

Background: We are not aware of any previous study that has examined predictive factors for blood transfusion after shoulder arthroplasty. We analyzed the association between clinical factors and the need for postoperative blood transfusion and documented the use and waste of predonated blood in a group of patients managed with shoulder arthroplasty. Methods: A retrospective study of 119 patients who underwent 124 shoulder arthroplasties (including eighty-seven primary uncomplicated total shoulder arthroplasties, twenty-seven revision or complicated primary total shoulder arthroplasties, and ten hemiarthroplasties) from 2001 to 2004 was performed. Logistic regression analysis was conducted to determine which clinical variables were predictive of transfusion. Results: A postoperative transfusion was received after thirty-one arthroplasties (25%). The strongest predictor of blood transfusion after shoulder arthroplasty was the preoperative hemoglobin level (likelihood ratio test = 37.8, p < 0.0001). Patients with a preoperative hemoglobin level of between 110 and 130 g/L had a five times greater estimated risk of transfusion than those with a level of > 130 g/L (p < 0.001). Gender, body mass index, preoperative diagnosis, comorbid conditions, use of anticoagulants or aspirin, autologous predonation status, type of anesthesia, operative time, and decrease in hemoglobin or hematocrit were not predictors of blood transfusion. One hundred and two (78%) of the 131 predonated autologous units were discarded. Patients with a preoperative hemoglobin level of > 130 g/L had the highest percentage of wasted units (90%; fifty-five of sixty-one). Preoperative autologous blood donation did not eliminate the risk of allogeneic blood transfusion in autologous donors. Conclusions: The preoperative hemoglobin level is the strongest predictor of blood transfusion after shoulder surgery, and individuals with a preoperative hemoglobin level of < 110 g/L have the highest risk of transfusion. On the basis of these findings, we do not recommend autologous predonation for individuals with a preoperative hemoglobin level of > 130 g/L, to avoid unnecessary expense and waste.