Predictors of blood transfusions in spinal instrumentation and fusion surgery

Study Design. A retrospective review of 244 adult spine instrumentation and fusion surgery cases (1994-1995) from one institution. Objectives. To ascertain the predictors of blood transfusions for adult patients undergoing different types of multilevel spine surgery. Summary of Background Data. Blood loss and transfusion requirements during and after multilevel spine surgeries have always been perceived as great. Identifying the predictors of blood transfusion with this type of surgery may aid in reducing the amount of blood loss and the transfusion requirements. Methods. The charts of 244 adult patients who underwent multilevel spine surgery from January 1994 to July 1995 were retrospectively reviewed. Results. A Targe percentage of patients required blood transfusion. The significant determinants for increased amounts of allogeneic red blood cell units transfused on the day of surgery using linear multiple regression modeling were low preoperative hemoglobin concentration, tumor surgery, increased number of posterior levels surgically fused, history of pulmonary disease, decreased amount of autologous blood available, and no use of the Jackson table (R-2 = 0.63). The significant determinants for an increased amount of autologous red blood cell units transfused on the day of surgery using linear multiple regression modeling were increased autologous red blood cells available, low preoperative hemoglobin concentration, and increased number of posterior levels surgically fused (R-2 = 0.60). Conclusion. The need for transfusion is associated with multiple factors, suggesting that a multifaceted, integrated approach may be necessary to reduce this risk.