Quantitative electromyographic train-of-four monitoring to determine rocuronium infusion requirements during major surgery in pediatric patients

ABSTRACT Background: Neuromuscular blocking agents (NMBAs) are commonly used during anesthetic care to facilitate endotracheal intubation, prevent intraoperative movement, and provide muscle relaxation during surgical procedures. Options for dosing include both intermittent bolus administration and continuous infusion. Methods: This prospective study investigated rocuronium infusion requirements during intraoperative care in a cohort of pediatric patients, using an electromyography (EMG)-based train-of-four monitor. Neuromuscular block (NMB) was provided by an initial intravenous bolus of rocuronium (0.5–0.6 mg/kg), followed by a continuous rocuronium infusion at 0.6 mg/kg/h, and titrated to maintain a train-of-four count (TOFC) of 1/4. Results: The final study cohort included 48 pediatric patients, ranging in age from 3 months to 18 years (median age 13 years) and in weight from 5.2 to 132 kg (median weight 55.9 kg). The total rocuronium infusion time across all patients was 11,735 min. The median initial bolus dose of rocuronium was 0.8 mg/kg (interquartile range [IQR]: 0.7, 1.1 mg/kg). The infusion dose ranged from 0.1 to 0.72 mg/kg/h (median dose 0.48 mg/kg/h). Twenty-six patients (54%) received at least one rescue bolus to maintain one twitch in the TOFC. Among these patients, the majority ( n = 15, 58%) received only one rescue bolus during the procedure. The median rescue bolus dose administered was 0.2 mg/kg (IQR: 0.2, 0.3). There were no cases of residual NMB, no need for additional rescue reversal after the initial dose of sugammadex, or other adverse effects related to anesthetic care. Conclusion: Rocuronium infusion requirements can be accurately titrated using an EMG-based TOF monitor during prolonged surgical procedures. This study accurately provides a dosing scheme for the intraoperative use of rocuronium infusions during these procedures, demonstrating that the median infusion requirement is 0.48 mg/kg/h.