A comparison of intravenous sugammadex and neostigmine + atropine reversal on time to consciousness during wake-up tests in spinal surgery.

Objective: The effect of sugammadex on consciousness is not yet fully understood. This prospective, randomized, double-blind, multicenter study was performed to compare the effects of intravenous (IV) sugammadex and neostigmine + atropine reversals on time-to-consciousness during intraoperative wake-up tests in patients undergoing spinal surgery.

Subjects And Methods: A total of 66 American Society of Anesthesiologists I-II patients aged 10-25 years undergoing spinal surgery were recruited. In all patients, bispectral index (BIS), motor-evoked potential (MEP), somatosensory-evoked potentials (SSEP), and train-of-four (TOF) scores were monitored. Patients received the same total IV anesthesia protocol with a propofol-remifentanil mixture. Patients were randomly allocated into two groups. During wake-up test, when the TOF count reached 2 (T), either sugammadex 2 mg.kg in group S or neostigmine 0.04 mg.kg + atropine 0.01 mg.kg in group N were administered. BIS, SSEP, MEP was recorded when TOF ratio reached 90, whereas time-to-consciousness (Time) was recorded when the patient responded to verbal commands.

Results: BIS (77.4 ± 4.7, 74.8 ± 3.7), SSEP(36 ± 9.9, 29.7 ± 8.5), and MEP (465.3 ± 34.8, 431.3 ± 28.2) values were significantly greater in group S than in group N (P < 0.05 for each variables). Time was significantly shorter with sugammadex than with the neostigmine + atropine combination (P < 0.05).

Conclusion: Using IV sugammadex 2 mg.kg reversal provides faster responses to verbal commands than neostigmine-atropine combination during the intraoperative wake-up test in patients undergoing spinal surgery because the time to consciousness was significantly shorter. This difference was thought to be related with faster return of neuromuscular transmission because the TOF ratio was >0.9 well before return of consciousness in both groups.