Impact of liberal intraoperative allogeneic blood transfusion on postoperative morbidity and mortality in major thoracic and lumbar posterior spine instrumentation surgeries.

Purpose: To investigate the impact of intraoperative blood transfusion on outcomes in patients who had major thoracic and lumber posterior spine instrumentation surgery.

Methods: Retrospective study included patients who underwent major spine surgery between 2013 and 2017. Patients' demographics, surgical charts, anesthesia charts, discharge charts and follow-up outpatient charts were reviewed. Data collection included: age, gender, BMI, Charlson Co-morbidity Index (CCI) scores, American Society of Anesthesiologists (ASA) scores, amount of estimated blood loss [% estimated blood volume (%EBV)], amount of blood transfused during surgery and post-surgery before discharge, number of fusion levels, pre- and postoperative hemoglobin (Hb) levels, and length of hospital stay. Also collected in-hospital postoperative complications (cardiovascular, pulmonary, infections and deaths). Patients' postoperative intubation status data documented. Reviewed follow-up charts to document any complications.

Results: Sample size = 289; No transfusion = 92; transfusion = 197. Transfused patients were significantly older, p < 0.001, higher average BMIs (p < 0.001); ASA scores (p < 0.001); CCI scores (p < 0.001), mean postoperative Hb level (p = 0.004), average intraoperative %EBV loss (p < 0.001), longer hospital stays (p = 0.003). Non-transfusion cohort had significantly higher proportion of patients (p < 0.001) extubated immediately after surgery. Seventeen patients had at least one in-hospital complication, p = 0.05. Complications were not significant among groups.

Conclusion: Intraoperative blood transfusions and high volume intraoperative allogeneic blood transfusions did not increase risk for in-hospital complications or surgical site infections. Delayed extubations noticed in patients who received higher volumes of intraoperative allogeneic blood transfusions. High-volume intraoperative blood transfusions increased length of hospital stays. High post-hospital surgical infections associated with high volume intraoperative blood transfusions. Results should be interpreted cautiously due to small sample size.