[Comparison of propofol and midazolam on patients undergoing spinal surgery with intraoperative wake-up test: randomized clinical trial]

Abstract

Background and objectives: Instrumentation in correction operations for spinal deformities carries a 0.5-5% risk of injuring the spinal cord. The wake-up test is used for early detection of these injuries. In this study we compared the effects of propofol and midazolam during wake-up test in scoliosis surgery.

Methods: Thirty patients were randomly assigned as group P and group M. Anesthesia was induced with propofol 2.5mgkg(-1) for group P or midazolam 0.5mgkg(-1) for group M with remifentanil 0.5μgkg(-1) and cisatracurium 0.15mgkg(-1) for both groups. At the maintenance of anesthesia O2/air and infusions of remifentanil and cisatracurium were used. In group P, propofol 6-10mgkg(-1)h(-1) and in group M, midazolam 0.5mgmgkg(-1) were preferred. Approximately 15min before the wake-up test, all drugs were discontinued. At the wake-up test, anesthesiologist asked the patients to open their eyes and squeeze his/her hand at every 30s until the patients responded. Then patients were told to wiggle their toes. Hemodynamic parameters, time of eye-opening, appropriate movement upon verbal command were evaluated. BIS frequency throughout the operation was recorded.

Results: The eye opening time was 9±2.15min in group P and 7±3.15min in group M. Motor movement time was 12±2.55min in group P and 21.25±3.93min in group M.

Conclusion: Propofol provided better wake-up conditions and conducted a better neurologic assessment within the same BIS values than midazolam.

Keywords: BIS; Cirurgia de coluna; Midazolam; Propofol; Spine surgery; Teste de despertar; Wake‐up test.