Agreement of Train-of-Four Count by Thai Peripheral Nerve Stimulator Compare with TOF-Watchâ SX

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Thewarug Werawatganon
Tayard Desudchit
Korranis Pirompanich
Kasidet Tailanan
Phakwalan Hamta-nont


Background: The incidence of residual neuromuscular blockade after general anesthesia is high. There are recommendations to monitor neuromuscular function during anesthesia with muscle relaxants, but clinical implementation is still low. One of the reasons is the availability of the low-cost equipment. The objective of this study aims to evaluate the train-of-four (TOF) count by the Royal College of Anesthesiologists of Thailand (RCAT) peripheral nerve stimulator side by side with the TOF-Watch® SX. Methods: We studied patients undergoing general anesthesia with non-depolarizing neuromuscular blocking agents. Every patient was given train-of-four stimulation with both peripheral nerve stimulators 15 seconds apart. Videos were recorded and randomly interpreted later to evaluate the agreement of the train-of-four count. Results: We obtained 269 pairs of data from 53 patients. Most of TOF count from TOF-Watch®SX and RCAT peripheral nerve stimulators in each pair was nearly the same with a weighted kappa coefficient of 0.9076 (95% confidence interval 0.8753-0.9399, P<0.001). Conclusion: This study shows TOF count from TOF-Watch® SX and RCAT peripheral nerve stimulator has high agreement. RCAT peripheral nerve stimulator is simple and cost-saving, which can promote its use for neuromuscular blockade moni-toring during anesthesia. Further improvements to add quantitative measurement will be beneficial.

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