Predictors of transfusion in adults undergoing elective posterior thoracolumbar spinal fusion: a retrospective case series

Abstract

Background: Posterior thoracolumbar spinal fusion surgery can be associated with significant blood loss. The purpose of this study was to investigate suspected risk factors of blood transfusion in posterior thoracolumbar fusion patients and determine if blood transfusion had a negative impact on the outcomes for those patients after surgery. Methods: All adults undergoing posterior thoracolumbar spine fusion in our institution from May 2015 to May 2018 were included. Data collected included demographic data as well as body mass index (BMI), preoperative hemoglobin, American Society of Anesthesiologists (ASA) classification, change in hemoglobin, estimated blood loss, incidence of blood transfusion, number of units transfused, number of levels fused, length of stay, and readmission within 30 days. The data were analyzed to correlate these variables with the frequency of blood transfusion and to assess the association of adverse outcomes after blood transfusion. Results: This study included 125 patients. Six patients (4.8%) required readmission within the first 30 days after discharge. Length of stay averaged 8.4 days (range 3 to 74). Eighteen patients (14.4%) required blood transfusion perioperatively. When multiple variables were analyzed for any correlations, the number of levels fused, age, and BMI had statistically significant correlations with the need for blood transfusion (P<0.005). None of the other factors showed any statistically significant correlation. Patients who required blood transfusion were more likely to stay in the hospital more than 7 days (P<0.005). Conclusions: Patients undergoing posterior thoracolumbar fusion are more likely to require blood transfusion if they are older, have a higher BMI, or have a multilevel fusion. Receiving a blood transfusion is associated with increased complication rates. Level of Evidence: Level IV.