An interventional study of Sugammadex 1 mg/kg Group and Sugammadex 2 mg/kg Group in Neuromuscular Blockade Reversal Agent, Perioperative Complications and Anesthesia, General, sponsored by Wonkwang University Hospital. Recruiting at 1 site in South Korea. Open to participants aged 19 Years to 70 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-07.
Sponsored by Wonkwang University Hospital · Not applicable, Interventional, and Prevention
Study Objective:
This study aims to evaluate the incidence, severity, and risk factors of sugammadex-induced mouth clenching during neuromuscular blockade (NMB) reversal in adult surgical patients.
Study Design:
This prospective, randomized, double-blind, controlled clinical trial enrolls adult patients (ASA physical status I-II, aged 19-70 years) undergoing elective surgery under general anesthesia with rocuronium. Patients will be randomized into four groups to receive either sugammadex at doses of 1 mg/kg, 2 mg/kg, or 4 mg/kg, or a combination of pyridostigmine and glycopyrrolate.
Primary Outcome:
The primary outcome is the incidence of clenching within 10 minutes after NMB reversal, assessed by clinical observation, masseter EMG, and airway pressure changes, using a novel five-grade severity scale.
Secondary Outcomes:
Secondary outcomes include the severity of clenching, time to TOF ratio ≥0.9, BIS values at clenching onset, complications, and identification of risk factors such as dose, sex, BIS, age, BMI, and rocuronium dose.
Significance:
This study seeks to improve perioperative safety by identifying modifiable risk factors and informing dose adjustments or alternative reversal strategies to prevent sugammadex-induced clenching, particularly in high-risk populations.
This prospective, randomized, double-blind clinical trial aims to investigate the incidence, risk factors, and clinical implications of sugammadex-induced clenching during neuromuscular blockade reversal under general anesthesia. Sugammadex, a selective relaxant binding agent, is widely used for the rapid reversal of rocuronium-induced neuromuscular blockade. However, reports of jaw clenching and masseter muscle contraction following sugammadex administration have raised safety concerns, particularly regarding airway management and patient discomfort during emergence from anesthesia.
A total of 240 adult patients (ASA physical status I-II, aged 19 to 70 years) scheduled for elective surgery under general anesthesia with rocuronium will be enrolled. Participants will be randomly assigned to one of four groups in a 1:1:1:1 ratio: sugammadex 1 mg/kg (S1), 2 mg/kg (S2), 4 mg/kg (S4), or pyridostigmine 0.2 mg/kg with glycopyrrolate 0.01 mg/kg (PG) as the control. Clenching events will be assessed within 10 minutes of drug administration using three criteria: visible jaw clenching, increased masseter electromyographic (EMG) activity (>50 μV for ≥2 seconds), and a rise in airway pressure (>5 cm H₂O). Severity will be graded using a novel five-level classification system.
Secondary outcomes include the severity and timing of clenching, time to train-of-four (TOF) ratio ≥0.9, bispectral index (BIS) value at the time of clenching onset, airway-related complications, and risk factor analysis based on dose, sex, BIS, age, BMI, and total rocuronium dose.
This study hypothesizes a dose-dependent increase in clenching with higher doses of sugammadex, potentially with a higher incidence in female patients and those with higher BIS values at reversal."
Exclusion Criteria:
Participants receive 1 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Drug: Sugammadex 1 mg/kg Group
Participants receive 2 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Drug: Sugammadex 2 mg/kg Group
Participants receive 4 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Drug: Sugammadex 4 mg/kg Group
Participants receive pyridostigmine 0.2 mg/kg and glycopyrrolate 0.01 mg/kg intravenously for reversal of rocuronium-induced neuromuscular blockade.
Drug: Pyridostigmine/Glycopyrrolate Group
Participants receive 1 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Also known as: S1
Participants receive 2 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Also known as: S2
Participants receive 4 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Also known as: S4
Participants receive pyridostigmine 0.2 mg/kg and glycopyrrolate 0.01 mg/kg intravenously for reversal of rocuronium-induced neuromuscular blockade.
Also known as: PG
Incidence of Mouth Clenching After Neuromuscular Blockade Reversal
Clenching is defined as any of the following occurring within 10 minutes after administration of neuromuscular blockade reversal agents: (1) visible jaw clenching observed by the anesthesiologist, (2) masseter muscle electromyography (EMG) activity greater than 50 μV sustained for ≥2 seconds, or (3) airway pressure increase \>5 cm H₂O.
Time frame: Within 10 minutes after administration of neuromuscular blockade reversal agent
Severity of Mouth Clenching
Graded using a novel five-grade severity scale based on degree of jaw closure, EMG intensity, airway pressure, and need for intervention.
Time frame: Within 10 minutes after reversal agent administration
Time to Recovery of Train-of-Four (TOF) Ratio ≥0.9
Measured using peripheral nerve stimulator; defined as time from reversal agent injection to TOF ratio ≥0.9.
Time frame: Up to 10 minutes after administration
Bispectral Index (BIS) at Clenching Onset
BIS value recorded at the time clenching is first detected.
Time frame: At time of clenching event, within 10 minutes post-reversal
Peak Airway Pressure
Maximum airway pressure measured within 10 minutes after administration of reversal agent.
Time frame: Within 10 minutes post-reversal
Incidence of Clenching-Related Complications
Incidents such as bite injury, airway obstruction, or need for additional airway intervention during or after reversal.
Time frame: Within 10 minutes post-reversal
Plan to share: Yes — Individual participant data (IPD) that underlie the results reported in this article will be shared, including study protocol, statistical analysis plan, and analytic code.
Supporting information: Study protocol, Sap, Icf, Csr, Analytic code
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Wonkwang University Hospital