Assessing blood volume returned with use of intraoperative cell salvage in adult spinal deformity correction.

Purpose: While multiple studies have evaluated the role of intraoperative red blood cell salvage (IOCS) in instrumented posterior spinal fusion as a method to reduce allogenic blood transfusion and its associated risks and cost, few studies have quantified the blood available for return to the patient when using IOCS. Given this paucity of data, the purpose of this study was to evaluate the relationship between estimated blood loss and cell saver volume returned.

Methods: Patients aged 18 years or older who underwent elective spinal fusion for correction of deformity requiring six or more levels of fusion were included. Demographic data, surgical details, EBL as measured by cell saver, and cell saver blood volume returned were recorded.

Results: 138 consecutive patients were included in the study. Average EBL as measured by cell saver across 138 cases was 734 cc. Based on patients' height, weight, and sex, the average percentage of estimated circulating blood volume lost during surgery was 15.9%. Average EBL per level was 84.2 cc.; mean percentage of total blood volume lost per level was 1.8%. Average blood volume returned was 256 cc., resulting in an average 34.9% of blood loss returned to the patient via IOCS.

Conclusions: On average, 34.9% of blood lost was subsequently transfused. While literature on this topic is very limited, this finding was similar to smaller cohorts that have examined IOCS autologous transfusion volumes. A better understanding of the available fraction of blood for return may allow providers to predict the need for allogenic blood transfusion or more clearly evaluate cost effectiveness of IOCS.