Risk factors for allogeneic red blood cell transfusion in adult spinal deformity surgery

Study Design: Retrospective study. Purpose: To investigate the risk factors for allogeneic red blood cell (RBC) transfusion in adult spinal deformity (ASD) surgery. Overview of Literature: Studies have not thoroughly explored the roles of intraoperative hypothermia, autologous blood donation, hemostatic agent administration, which would provide a better understanding of the risk for perioperative RBC transfusion in ASD gery. Methods: The medical records of 151 patients with ASD who underwent correction surgery between 2012 and 2021 were retrospectively reviewed. Estimated blood loss and perioperative allogeneic transfusion were examined. Patients were categorized into two groups based on whether they received perioperative allogeneic blood transfusion. Logistic regression analysis was employed to investigate effect of age, sex, blood type, body mass index, American Society of Anesthesiologists' physical status, preoperative hemoglobin autologous blood donation, global spine alignment parameters, preoperative use of anticoagulants or antiplatelet medicine and nonsteroidal anti-inflammatory drugs, number of instrumented fusion levels, total operative duration, three-column osteotomy, lateral interbody fusion, pelvic fixation, intraoperative hypothermia, use of gelatin-thrombin based hemostatic agents, and intraoperative tranexamic (TXA) with simultaneous exposure by two attending surgeons. Results: The estimated blood loss was 994.2 +/- 754.5 mL, and 71 patients (47.0%) received allogeneic blood transfusion. In the logistic regression analysis, the absence of intraoperative TXA use and simultaneous exposure (odds ratio [OR], 26.3; 95% confidence interval 7.6-90.9; p <0.001), lack of autologous blood donation (OR, 21.2; 95% CI, 4.4-100.0; p <0.001), and prolonged operative duration (OR, 95% CI, 1.3-1.9; p <0.001) were significant independent factors for perioperative allogeneic blood transfusion in ASD surgery. Conclusions: Autologous blood storage, intraoperative TXA administration, and simultaneous exposure should be considered to mize perioperative allogeneic blood transfusion in ASD surgery, particularly in patients with anticipated lengthy surgeries.