Ease of Application of Various Neuromuscular Devices for Routine Monitoring

Subjective evaluations to confirm recovery from neuromuscular blockade with a peripheral nerve stimulator (PNS) is inadequate. Quantitative monitors are the only reliable method to confirm adequate recovery of neuromuscular function. Unfortunately, many clinicians are unfamiliar with such devices and there is concern that the introduction of objective monitoring would be exceedingly laborious and could cause workflow delays. This study investigates how long it takes experienced nurse anesthetists to apply various neuromuscular devices as well as their perception regarding the ease of application.

Twenty nurse anesthetists were consented and participated in an educational session that familiarized them with 3 devices: SunStim Plus PNS (SunMed, Grand Rapids, MI), the acceleromyography-based IntelliVue NMT device (Philips, Amsterdam, the Netherlands), and electromyography-based TetraGraph device (Senzime B.V., Uppsala, Sweden). Participants were timed while placing each monitor on patients in a real-world setting. For the quantitative devices (IntelliVue NMT and TetraGraph), participants were also timed when obtaining calibrated baseline train-of-four (TOF) ratios. Friedman test and pairwise Wilcoxon signed-rank tests were used to evaluate the difference in time to connect different devices. Participants were surveyed about how easy they found it to utilize these devices.

After adjusting for multiple comparison, time to connect was significantly less for PNS (median, 29; range, 16-58 seconds) compared to either the TetraGraph device (median, 62.8; range, 32-101 seconds; P < .001) or the IntelliVue NMT device (median, 46; range: 28-90 seconds; P < .001). The difference in time to connect between the TetraGraph device and the IntelliVue NMT device was not statistically significant (P = .053), but it took significantly less time to calibrate the TetraGraph device than the IntelliVue NMT device (median difference, -16; range, -88 to 49 seconds; P = .002). The participants found applying either the IntelliVue NMT device (P = .042) or the TetraGraph device (P = .048) more difficult than applying a PNS while finding it easier to calibrate the TetraGraph device versus the IntelliVue NMT device (P < .001).

It takes 19 seconds longer to apply a quantitative neuromuscular monitor (the IntelliVue NMT device) than a PNS. While this difference reached significance, this relatively minimal additional time represents an inappropriate barrier to the application of quantitative monitors. Regardless of which quantitative monitor was utilized, these nurse anesthetists found the application and utilization of such devices relatively straightforward.