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."
107 studies on the registry are indexed under Trismus; 19 are open to participants now.
This study's planned enrollment of 240 is above the median of 52 across 99 interventional studies indexed under Trismus.
Browse Trismus studies →Wonkwang University Hospital is the lead sponsor of 26 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
ASA physical status
The anaesthetists’ scale of health before surgery: I is healthy, II has a mild illness that is under control, III a severe one, IV a severe illness that is a constant threat to life. V and VI are used for the critically ill and for organ donors.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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
Drug page: Sugammadex
Participants receive 1 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Also known as: S1
Drug page: Sugammadex
Participants receive 2 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Also known as: S2
Drug page: Sugammadex
Participants receive 4 mg/kg of sugammadex intravenously for reversal of rocuronium-induced neuromuscular blockade.
Also known as: S4
Drug pages: Pyridostigmine · Glycopyrrolate
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, Statistical analysis plan, Informed consent form, Clinical study report, Analytic code
Time frame: Beginning 6 months and ending 36 months following article publication.
Access criteria: Researchers who provide a methodologically sound proposal and agree to sign a data access agreement.
Started Jul 2025 (actual). Primary completion is estimated for Sep 2026, 14 months after the start.
Of 57 non-industry interventional studies with no phase under Trismus, half reached primary completion within 8 months of starting (the median), counting those still running; a quarter within 4 and three quarters within 21. This study's planned 14 months is above that.
Counting every sponsor, half of 58 studies reached it within 8 months; a quarter within 4 and three quarters within 21.
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Studies of the drug tested here: Sugammadex
Wonkwang University Hospital