Orthopedic Surgery Transfusion Hemoglobin European Overview (OSTHEO) study: blood management in elective knee and hip arthroplasty in Europe*

Abstract
The purpose of this study was to assess current practices in blood management in elective orthopedic surgery in Europe. For this 225-center prospective survey, data were collected on 3996 patients. Actual perioperative blood loss was compared to preoperative estimates. Differences in Hb levels and other outcome variables for patients receiving allogeneic versus autologous transfusions were evaluated. The probability of allogeneic transfusion based on selected predictor variables was estimated. A total of 2640 (67%) hip and 1305 (33%) knee arthroplasty patients were evaluated. Estimated blood loss (median, 750 mL) was significantly lower than computed blood loss (median, 1944 mL). A total of 2762 (69%) patients received transfusions, including 1393 (35%) autologous-only and 1024 (25%) allogeneic-only. The probability of allogeneic transfusion decreased with increasing baseline Hb, but differentially so for men and women. Transfusion triggers were Hb levels of 8.93 +/- 1.83 g per dL for allogeneic transfusions, and 21 percent of these occurred when the Hb level was greater than 10 g per dL. Autologous blood transfusion was associated with a significantly lower rate (1%) of wound infections than allogeneic blood transfusion (4.2%). Accurate assessment of preoperative Hb levels, better estimation of perioperative blood loss, efficient use of autologous blood, adherence to transfusion guidelines, and pharmacologic alternatives contribute to effective and comprehensive blood and anemia management.