The aim of this study is to compare the use of a low dose sugammadex and neostigmine combined to glycopyrrolate to reverse a rocuronium induced moderate neuromuscular blockade.

Neuromuscular blocking agents (NMBAs) are administered by anesthesiologists for general anesthesia to facilitate endotracheal intubation and/or surgical conditions. Unfortunately, postoperative residual neuromuscular blockade (rNMB), is an adverse event usually observed after extubation in the postanesthesia care unit (PACU) after surgery. rNMB is associated with upper airway obstruction, reduced pharyngeal muscle coordination, decreased functional residual capacity, and impaired hypoxic ventilatory response and may lead to critical cardiopulmonary complications.To prevent those complications, monitoring NMBAs activity as well as appropriate reversal are crucial.

In the light of the strong evidence proving the superiority of sugammadex for the reversal of NMB, the investigators chose to examine whether a quarter dose (0.5 mg.kg-1) of sugammadex would be superior to neostigmine for the reversal of moderate NMB (TOF 1 to 3). The investigators believe that this strategy will encourage the routine use of sugammadex because of a drastically reduced cost per patient with an increased safety and less adverse events compared to neostigmine reversal.

This study will be conducted in a single center, double blinded, randomized controlled study.

Type of surgery: any surgery under general anesthesia in ASA 1-3 patients, fully consented.

In the OR, the investigators will place a standardized monitoring: ECG, non-invasive blood pressure and SpO2. The investigators will monitor the depth of anesthesia using the BIS index (Medtronic, Canada) and the intraoperative nociception balance using the NOL index (Medasense Ltd., Ramat Gan, Israel). Finally, the investigators will monitor neuromuscular blockade using TOF-scan® (Draeger, Mississauga, Canada). The stimulation electrodes will be placed on the forearm of the patient to monitor the response to ulnar stimulation of the adductor pollicis muscle.

The investigators will use adjusted body weight for the administration of the drugs used in our anesthesia protocol except for rocuronium, sugammadex and neostigmine that will be given based on the real actual body weight.

The primary objective of the study:

To compare the mean time for recovery of the TOF ratio to 0.9 (90%) at the end of the surgery for rocuronium induced moderate neuromuscular blockade (TOF 1 to 3 at the end of the surgery) in two groups: Group "N" for neostigmine and group "S" for sugammadex. Group N will receive the standard reversal (neostigmine 50 µg.kg-1 and glycopyrrolate 7 µg.kg-1) and group S will receive sugammadex 0.5 mg.kg-1.

Secondary objectives are listed below.

Based on a 2-sided alpha < 0.05 and 80% power, the investigators calculated that 64 patients per group was required to detect a clinically relevant effect size of 0.5 favouring S group. The sample size will be inflated to 144 (72 per group) to account for 10% withdrawals and loss of follow-up.

Study Duration: 12 months.

Study Center: Maisonneuve-Rosemont Hospital, CIUSSS de l'Est de l'Ile de Montreal (CEMTL), University of Montreal, Montreal, Quebec, Canada.

Adverse Events: None expected.

Inclusion Criteria:

• ASA 1-3 patients,
• Undergoing general anesthesia with rocuronium induced NMB,
• TOF 1-3 at the end of surgery,
• BMI < 36 kg.m-2,
• Age > 18 years old

Exclusion Criteria:

• History of coronary artery disease and unstable before surgery
• History of serious cardiac arrhythmia (including atrial fibrillation)
• Renal or hepatic dysfunction
• Obstructive sleep apnea requiring continuous positive airway pressure (CPAP) machine
• Neuromuscular disease
• Allergy to any drug used in the study protocol

Two groups of patients randomized into Group "N" for neostigmine and group "S" for sugammadex. Group N will receive the standard reversal (neostigmine 50 µg.kg-1 and glycopyrrolate 7 µg.kg-1) and group S will receive sugammadex 0.5 mg.kg-1. Randomization will be done prior to the entrance in the OR, the day of the surgery.