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

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 2.5 mg kg^-1 for group P or midazolam 0.5 mg kg^-1 for group M with remifentanil 0.5 µg kg^-1 and cisatracurium 0.15 mg kg^-1 for both groups. At the maintenance of anesthesia O₂/air and infusions of remifentanil and cisatracurium were used. In group P, propofol 6-10 mg kg^-1 h^-1 and in group M, midazolam 0.5 mg mg kg^-1 were preferred. Approximately 15 min 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 30 s 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 ± 2.15 min in group P and 7 ± 3.15 min in group M. Motor movement time was 12 ± 2.55 min in group P and 21.25 ± 3.93 min in group M.

CONCLUSION:

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

Wake-up test; Propofol; Midazolam; BIS; Spine surgery