Use of the Surgical Blood Order Equation in Spinal Instrumentation and Fusion Surgery

Abstract
A retrospective review of 182 cases of adult spine instrumentation and fusion surgery (1994–1995) from one institution. To develop and retrospectively evaluate the use of the surgical blood ordering equation for patients undergoing spinal instrumentation and fusion surgery. The provision of effective and safe blood and blood products is the primary function of the hospital transfusion service. A quantification of blood bank efficiency is the crossmatch-to-transfusion ratio. The maximal surgical blood order schedule system has been used to improve the efficiency of surgical ordering practices. The current authors have developed a theoretically more efficient system, the surgical blood ordering equation, which incorporates patient factors for ordering red blood cell units for surgical patients. The charts of 63 patients with autologous red blood cells available and 119 adult patients with none available, who underwent multilevel spine surgery from January 1994 to July 1995, were reviewed. The surgical blood ordering equation was exactly correct in the ordering for 37 (20.3%) of 182 patients. The maximal surgical blood order schedule was exactly correct in ordering blood for 14 patients (7.6%). Use of the new surgical blood ordering equation to order red blood cells for surgery would result in a lower crossmatch-to-transfusion ratio than with the current system, the maximal surgical blood order schedule, for patients with autologous red blood cells available (1.0 vs. 1.3) and patients with none available (0.9 vs. 1.2). Incorporating patient factors resulted in increased efficiency of blood ordering practices.