Allogeneic transfusion requirements after autologous donations in posterior lumbar surgeries

Study Design. A retrospective study of blood transfusion practices after posterior lumbar spine surgery was performed. Objectives. To determine the overall use rate of autol- ogous blood donations for different spine surgeries, and to identify the risk of requiring additional allogeneic blood transfusions. Summary of Background Data. In an attempt to avoid allogeneic blood transfusions and its associated risks, patients frequently are asked to donate autologous blood before many elective spine surgeries. There is a lack of published data on the use rate for these autologous blood donations, and on their ability to prevent allogeneic blood exposure. Methods. A retrospective review of hospital charts and blood bank records was conducted on 191 consecutive patients who had undergone three categories of lumbar spine surgery: laminectomy alone, laminectomy with a noninstrumented posterolateral fusion, and laminectomy with an instrumented posterolateral fusion. Results. Nearly 80% of the autologous blood donated by patients who underwent simple laminectomies was wasted. However, the vast majority (70-90%) of patients who underwent fusion used their autologous blood. In the patients who underwent fusion, autologous blood donations decreased the risk of allogenic blood transfusions by 75% in noninstrumented fusions and 50% in instrumented fusions, as compared with the patients who elected not to donate blood before the fusion (P < 0.05). A substantial number of patients who underwent instrumented fusions (nearly 40%) required additional allogeneic blood transfusions despite predonation of blood. Conclusions. Autologous blood donations are indeed advantageous in decreasing allogeneic blood usage of patients undergoing fusion, but additional methods of blood conservation (intraoperative salvage and preoperative erythropoietin) seem necessary to diminish the allogeneic blood requirements further, especially in those patients undergoing instrumented lumbar fusion.