Comparison of the TOFscan and the TOF-Watch SX during pediatric neuromuscular function recovery: a prospective observational study

BACKGROUND: TOFscan is a three-dimensional acceleromyography neuromuscular monitoring device that does not require initial calibration before muscle relaxant injection. This study aimed to compare TOFscan with TOF-Watch SX, the currently widely accepted uni-dimensional acceleromyography, for use among the pediatric population. We aimed to assess the agreement between TOFscan with TOF-Watch SX in the pediatric population’s neuromuscular recovery. METHODS: A total of 35 children aged 6–12 years were enrolled. Prior to any muscle relaxant injection, TOFscan and TOF-Watch SX were applied at each opposite arm and monitoring began concurrently throughout neuromuscular recovery. Calibration was performed for TOF-Watch SX, and train-of-four values were recorded every 15 s. Agreement between the two devices was evaluated with Modified Bland-Altman analysis. RESULTS: The bias between TOF-Watch SX and TOFscan were all within the 95% limits of agreement. The bias and standard deviation were smaller and the limit of agreement was narrower in the normalized group than in the non-normalized group [normalized bias −0.002 (95% CI, −0.013 to 0.010), standard deviation (SD) 0.111 vs non-normalized bias 0.010 (95% CI, −0.003 to 0.0236), SD 0.127]. CONCLUSIONS: TOFscan reliably demonstrated lack of bias and good concordance with TOF-Watch SX throughout the neuromuscular recovery, especially when normalized. Despite technical limitations, the two devices were unbiased along the path of spontaneous and pharmacological reversal in pediatric patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT03775603. Registered on 13 March 2018 SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13741-021-00215-2.