Paired assessment of two electromyographic neuromuscular monitors: stimpod NMX450X versus Datex-Ohmeda E-NMT.

Quantitative neuromuscular monitoring (NMM) is widely recommended, yet its clinical adoption remains limited, partly due to usability issues. This study aimed to compare the clinical performance of two electromyography (EMG)-based NMM devices—the Datex-Ohmeda E-NMT module and the Stimpod NMS450X—under real-world operating room conditions. Twenty-four adult patients undergoing elective non-cardiac surgery were monitored simultaneously with both devices, applied contralaterally. Train-of-four (TOF) counts and TOF ratios were recorded at one-minute intervals. Agreement between devices was assessed using Bland–Altman analysis, repeatability coefficients, and the concordance correlation coefficient (CCC). The Datex-Ohmeda recorded an average of 121 TOF-count and 71 TOF-ratio values per patient, compared with 56 and 39, respectively, for the Stimpod. Inter-device correspondence was low, with numerous missing or physiologically implausible values on the Stimpod stream. The repeatability coefficient was 0.81 (95% CI: 0.80–0.83), indicating poor precision. The CCC was 0.662, consistent with weak agreement. In routine clinical use, the Stimpod NMS450X and Datex-Ohmeda E-NMT demonstrated poor concordance and high variability, likelyinfluenced by device-specific artifacts, connectivity limitations and electrode sensitivity.These findings highlight the need for device-specific validation of EMG NMM, both for clinical practice and for research purposes.