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Author Spotlight: Translational Applications of Stimulated SFEMG in Rodent Models
Published on: March 8, 2024
Comparison of two electromyography-based neuromuscular monitors, AF-201P and TetraGraph, in rocuronium-induced
Hanae Sato1, Hajime Iwasaki1, Akira Doshu-Kajiura1
1Department of Anesthesiology, Nihon University School of Medicine, 30-1 Oyaguchi, Kamicho, Itabashi-Ku, Tokyo 173-8610, Japan.
Background:
The study aimed to compare the responses obtained simultaneously from the newly developed electromyography (EMG)-based neuromuscular monitors, AF-201P and TetraGraph™, during rocuronium-induced neuromuscular block.
Methods:
Twenty patients were enrolled in this study. During total intravenous general anesthesia, train-of-four (TOF) responses following 0.9-mg/kg-rocuronium administration were monitored at the abductor digiti minimi muscle with AF-201P and TetraGraph on the contralateral arms. Sugammadex 2 mg/kg was administered when both devices showed TOF counts (TOFC) = 2. The primary outcome was time from rocuronium administration to the first appearance of the post-tetanic count (PTC) response (first PTC). The secondary outcomes were supramaximal current, baseline compound muscle action potential, onset time, time to TOFC = 1, time to TOFC = 2, and time from sugammadex administration to TOF ratio ≥ 0.9. We used the paired t-test and Wilcoxon signed-rank test to analyze parametric and non-parametric data, respectively. P < 0.05 defined statistical significance.
Results:
A total of 19 patients were analyzed. The supramaximal current was significantly lower with AF-201P than TetraGraph (31.7 ± 13.2 vs. 43.2 ± 8.2, p = .002). The time to first PTC (24.9 ± 9.4 vs. 27.3 ± 8.9 min, p = .026), time to TOFC = 1 (42.3 ± 9.0 vs. 45.1 ± 10.4 min, p = .03), and time to TOFC = 2 (52.0 ± 10.5 vs. 54.6 ± 11.7 min, p = .014) were significantly faster with AF-201P than with TetraGraph. There were no significant differences in the other outcomes between the devices.
Conclusions:
AF-201P showed faster recovery of rocuronium-induced neuromuscular block compared with TetraGraph.
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