Neostigmine Versus Sugammadex for Reversal of Neuromuscular Blockade in Elderly Patients: A Blinded Randomised Study

Reversal of rocuronium-induced neuromuscular blockade (NMB) is possible with either neostigmine or sugammadex to prevent residual NMB. In adults, sugammadex provides faster reversal and has fewer side effects compared to neostigmine, even when combined with glycopyrrolate. In elderly patients, rocuronium has a longer onset time and duration of action; however, little is known about the reversal of rocuronium-induced NMB with either sugammadex or neostigmine and the recovery of muscle function postoperatively. The aim of this study was to determine the time to full recovery of neuromuscular function, defined as Train of Four ratio (TOF) ≥ 0.9 after reversal with either neostigmine 50 μg kg^-1 or sugammadex 2 mg kg^-1 in elderly patients aged 75 years or above undergoing total intravenous anaesthesia with rocuronium-induced moderate NMB. We hypothesised that sugammadex 2 mg kg^-1 provides a shorter time to TOF ≥ 0.9 compared to neostigmine 50 μg kg^-1.

We included 41 patients aged ≥ 75 years with American Society of Anesthesiologists (ASA) physical health classes I-IV scheduled for robotic-assisted laparoscopic surgery under total intravenous anaesthesia with rocuronium. Patients were randomised to reversal with neostigmine/glycopyrrolate 50/10 μg kg^-1 or sugammadex 2 mg kg^-1 if the depth of NMB was within the range from TOF count of 2 to a TOF ratio < 0.60. The primary outcome was time to TOF ≥ 0.9, measured from the start of administration of the reversal agent. Secondary outcomes were signs of residual NMB within 90 min after administration of the reversal agent.

A total of 40 patients were evaluated for the primary outcome. A total of 17 patients received neostigmine/glycopyrrolate and 23 patients received sugammadex. Time to TOF ≥ 0.9 was significantly shorter with sugammadex: 147 s (SD 100) vs. 573 s (SD 501) with a difference of 427 s (95% CI: 205 to 648). No difference was found in the occurrence of clinical signs of residual NMB.

Time to TOF ≥ 0.9 was shorter after reversal with sugammadex 2 mg kg^-1 compared to neostigmine/glycopyrrolate 50/10 μg kg^-1 in elderly patients administered rocuronium during total intravenous anaesthesia. For neostigmine a large variation in time to recovery was detected. No significant difference in clinical signs of residual NMB was found.

This trial in an elderly surgical cohort assessed reversal times for rocuronium comparing sugammadex and neostigmine. Sugammadex demonstrated faster and more predictable reversal effects in this cohort.

ClinicalTrials.gov identifier: NCT06228092.