Comparison of novel and manufacturer-recommended electrode placements for electromyography-based neuromuscular monitoring: a randomized, within-participant study

We compared a novel electrode placement (“Pattern Cross”) with the original (Pattern O–N) and revised (Pattern N–N) manufacturer-recommended placements for electromyography-based neuromuscular monitoring using Nihon-Kohden NM-345Y™ electrodes. In this single-center, randomized, blinded, within-participant study, 44 patients undergoing laparoscopic surgery were assigned to the Pattern O–N versus Pattern Cross (n = 25) or Pattern N–N versus Pattern Cross (n = 19); Cross was applied to one forearm and the comparator to the contralateral forearm. Monitoring was calibrated at 90° supination before forearm repositioning to 0° pronation.

The primary endpoint was time from initial rocuronium administration to first post-tetanic count (PTC) appearance. After outlier exclusion, mean time to first PTC appearance did not differ between Pattern O–N and Cross (mean difference, 5 min; 95% confidence interval [CI], −3 to 12) or between Pattern N–N and Cross (−1 min; 95% CI, −7 to 4). Secondary endpoints were generally similar between Pattern N–N and Cross.

Within-participant difference analysis showed marked delays or absent PTC detection with Pattern O–N or Pattern N–N in selected participants. Pattern Cross did not demonstrate superiority for the primary endpoint, but may help maintain stable recovery-signal detection during forearm pronation. Trial registration: UMIN-CTR, UMIN000053918, registered 20/03/2024.

We thank Editage (www.editage.jp) for its English language editing services. We also express our sincere gratitude to the Nihon-Kohden Corporation and the Department of Anesthesia at Sasebo City General Hospital for their support in handling equipment. Department of Anesthesiology and Intensive Care Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan Madoka Makino, Shohei Kaneko, Akira Iwamizu, Hanako Ishikawa, Kaho Matsuzaki, Shohei Tobinaga, Shogo Hirano, Kana Miyagawa, Taiga Ichinomiya, Hiroaki Murata, Osamu Yoshitomi, Keiko Ogami-Takamura & Tetsuya Hara Department of Macroscopic Anatomy, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan Clinical Research Center, Nagasaki University Hospital, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan The authors declare no competing interests.

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Nagasaki University Hospital Ethics Committee (Approval number: 24031802) on 26 March 2024. Informed consent was obtained from all individual participants included in the study.

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Below is the link to the electronic supplementary material. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material.