Energy Consumption and Substrate Utilization During Spinal Surgery

This study aims to measure surgeon physiologic stress and energy expenditure during adult spine surgery. Energy expenditures were assessed based on patient BMI, lead use, instrumentation/intraoperative navigation, primary/revision surgeries, tranexamic acid (TXA) use, and anatomic region involved. The senior author wore a heart rate (HR) monitor and triaxial accelerometer during spinal surgeries, providing assessments of mean HR, maximum HR, calories consumed/minute, and calories as measured by a Polar device (P calories) and Fitbit device (F calories). One hundred sixty-two surgeries were included. Median patient age was 62 years. Median BMI was 29.02. Significant differences existed for BMI and estimated blood loss (P < 0.05). TXA use had a significant effect on case time, estimated blood loss, P calories, F calories, and Kcal/min (P < 0.05). Instrumentation use was significant for all variables (P < 0.05), except for mean HR and Kcal/min (P > 0.05). Lead use did not have a significant effect on max HR, P calories, F calories, and Kcal/min (P > 0.05). Navigation use was associated with significant differences for every variable tested (P ≤ 0.05). Differences were observed between primary and revision surgeries for case time, estimated blood loss, and F calories (P < 0.05). In spinal surgery, the use of navigation, instrumentation use, TXA use, and performing revision surgeries were associated with increased energy expenditure and can potentially increase surgeon fatigue.