Pro-Con Debate: Do We Need Quantitative Neuromuscular Monitoring in the Era of Sugammadex?

Pediatric Intraoperative Electromyographic Responses at the Adductor Pollicis and Flexor Hallucis Brevis Muscles: A Prospective, Comparative Analysis

BACKGROUND

Peripheral nerve stimulation with a train-of-four (TOF) pattern can be used intraoperatively to evaluate the depth of neuromuscular block and confirm recovery from neuromuscular blocking agents (NMBAs). Quantitative monitoring can be challenging in infants and children due to patient size, equipment technology, and limited access to monitoring sites. Although the adductor pollicis muscle is the preferred site of monitoring, the foot is an alternative when the hands are unavailable. However, there is little information on comparative evoked neuromuscular responses at those 2 sites.

METHODS

Pediatric patients undergoing inpatient surgery requiring NMBA administration were studied after informed consent. Electromyographic (EMG) monitoring was performed simultaneously in each participant at the hand (ulnar nerve, adductor pollicis muscle) and the foot (posterior tibial nerve, flexor hallucis brevis muscle).

RESULTS

Fifty patients with a mean age of 3.0 ± standard deviation (SD) 2.9 years were studied. The baseline first twitch amplitude (T1) of TOF at the foot (12.46 mV) was 4.47 mV higher than at the hand (P <.0001). The baseline TOF ratio (TOFR) before NMBA administration and the maximum TOFR after antagonism with sugammadex were not different at the 2 sites. The onset time until the T1 decreased to 10% or 5% of the baseline value (T1) was delayed by approximately 90 seconds (both P =.014) at the foot compared with the hand. The TOFR at the foot recovered (TOFR ≥0.9) 191 seconds later than when this threshold was achieved at the hand (P =.017). After antagonism, T1 did not return to its baseline value, a typical finding with EMG monitoring, but the fractional recovery (maximum T1 at recovery divided by the baseline T1) at the hand and foot was not different, 0.81 and 0.77, respectively (P =.68). The final TOFR achieved at recovery was approximately 100% and was not different between the 2 sites.

CONCLUSIONS

Although this study in young children demonstrated the feasibility of TOF monitoring, interpretation of the depth of neuromuscular block needs to consider the delayed onset and the delayed recovery of TOFR at the foot compared to the hand. The delay in achieving these end points when monitoring the foot may impact the timing of tracheal intubation and assessment of adequate recovery of neuromuscular block to allow tracheal extubation (ie, TOFR ≥0.9).

Improving Neuromuscular Monitoring Through Education-Based Interventions and Studying Its Association With Adverse Postoperative Outcomes: A Retrospective Observational Study

BACKGROUND

We assessed the association between education-based interventions, the frequency of train-of-four (TOF) monitoring, and postoperative outcomes.

METHODS

We studied adults undergoing noncardiac surgery from February 1, 2020 through October 31, 2021. Our education-based interventions consisted of 3 phases. An interrupted time-series analysis, adjusting for patient- and procedure-related characteristics and secular trends over time, was used to assess the associations between education-based interventions and the frequency of TOF monitoring, postoperative pulmonary complications (PPCs), 90-day mortality, and sugammadex dosage. For each outcome and intervention phase, we tested whether the intervention at that phase was associated with an immediate change in the outcome or its trend (weekly rate of change) over time. In a sensitivity analysis, the association between education-based interventions and postoperative outcomes was adjusted for TOF monitoring.

RESULTS

Of 19,422 cases, 11,636 (59.9%) had documented TOF monitoring. Monitoring frequency increased from 44.2% in the first week of preintervention stage to 83.4% in the final week of the postintervention phase. During the preintervention phase, the odds of TOF monitoring trended upward by 0.5% per week (odds ratio [OR], 1.005; 95% confidence interval [CI], 1.002-1.007). Phase 1 saw an immediate 54% increase (OR, 1.54; 95% CI, 1.33-1.79) in the odds, and the trend OR increased by 3% (OR, 1.03; 95% CI, 1.01-1.05) to 1.035, or 3.5% per week (joint Wald test, P < .001). Phase 2 was associated with a further immediate 29% increase (OR, 1.29; 95% CI, 1.02-1.64) but no significant association with trend (OR, 0.96; 95% CI, 0.93-1.01) of TOF monitoring (joint test, P = .04). Phase 3 and postintervention phase were not significantly associated with the frequency of TOF monitoring (joint test, P = .16 and P = .61). The study phases were not significantly associated with PPCs or sugammadex administration. The trend OR for 90-day mortality was larger by 24% (OR, 1.24; 95% CI, 1.06-1.45; joint test, P = .03) in phase 2 versus phase 1, from a weekly decrease of 8% to a weekly increase of 14%. However, this trend reversed again at the transition from phase 3 to the postintervention phase (OR, 0.82; 95% CI, 0.68-0.99; joint test, P = .05), from a 14% weekly increase to a 6.2% weekly decrease in the odds of 90-day mortality. In sensitivity analyses, adjusting for TOF monitoring, we found similar associations between study initiatives and postoperative outcomes. TOF monitoring was associated with lower odds of PPCs (OR, 0.69; 95% CI, 0.55-0.86) and 90-day mortality (OR, 0.79; 95% CI, 0.63-0.98), but not sugammadex dosing (mean difference, -0.02; 95% CI, -0.04 to 0.01).

CONCLUSIONS

Our education-based interventions were associated with both TOF utilization and 90-day mortality but were not associated with either the odds of PPCs or sugammadex dosing. TOF monitoring was associated with reduced odds of PPCs and 90-day mortality.

The Incidence of Residual Neuromuscular Block in Pediatrics: A Prospective, Pragmatic, Multi-institutional Cohort Study

Introduction Residual neuromuscular block, defined as a quantitatively measured train-of-four ratio (TOFr) <0.9, is common postoperatively. Using a pragmatic trial design, we hypothesized that qualitative and/or clinical assessment of neuromuscular block would inadequately detect residual block following antagonism with neostigmine or sugammadex. Method After IRB approval and written informed consent, 74 children (aged 2-17 years), undergoing elective surgery and receiving rocuronium, were prospectively enrolled in the study at Children's Hospital Colorado and Children's Healthcare of Atlanta. Routine clinical practice at both institutions consisted of clinical signs and/or qualitative assessment with peripheral nerve stimulators. Children at the Colorado hospital routinely received sugammadex antagonism; whereas children at the Atlanta hospital received neostigmine. Residual neuromuscular block was assessed postoperatively using quantitative electromyography. If TOFr was <0.9, patients received sugammadex until TOFr ≥0.9. Result Qualitative and clinical assessment failed to detect residual block in 29.7% of patients in the neostigmine reversal cohort (adjusted odds ratio (aOR) 29.8, 95% confidence interval (CI): 2.7 to 5,559.5, p-value = 0.002). No residual block was detected in the sugammadex reversal cohort. A correlation between increasing patient weight and incidence of postoperative residual block was observed in the neostigmine cohort (aOR 1.05, 95% CI: 1.02 to 1.10, p-value = 0.002). Conclusion Qualitative and/or clinical assessment of neuromuscular block inadequately detects residual block following neostigmine antagonism.

Perioperative management of obstructive sleep apnea in lower extremity orthopedic procedures: A review of evidence to inform the development of a clinical pathway

Obstructive sleep apnea (OSA) is unrecognized in as high as 80% of patients before surgery. When untreated, OSA increases a surgical patient's propensity for airway collapse and sleep deprivation lending to a higher risk for emergent re-intubation, prolonged recovery time, escalation of care, hospital readmission, and longer length of stay. We have reviewed the evidence regarding diagnostic performance of OSA screening methods and the impact of perioperative management strategies on postoperative complications among patients with diagnosed or suspected OSA who are undergoing orthopedic surgery. We then integrated the data and recommendations from professional society guidelines to develop an evidence-based clinical care pathway to optimize the perioperative management of this surgical population. Successful management of patients with diagnosed or suspected OSA encompass five facets of care: screening, education, airway management, medications, and monitoring. This narrative review revealed two gaps in the evidence to inform management of patients undergoing orthopedic surgery 1) during the perioperative setting to include evidence-based interventions that reduce postoperative complications and 2) after discharge to an unmonitored environment. The clinical care pathway as well as perspectives for future research are discussed.

How robust are the STRONGER and STIL-STRONGER studies?

In 2020, the Sugammadex vs Neostigmine for Reversal of Neuromuscular Blockade and Postoperative Pulmonary Complications (STRONGER) study provided evidence for the first time that use of sugammadex is associated with fewer postoperative pulmonary complications than use of neostigmine. In a recent publication in the British Journal of Anaesthesia, a secondary analysis of the same data, the Association Between Neuromuscular Blockade Reversal Agent Choice and Postoperative Pulmonary Complications (STIL-STRONGER) study, has produced similar evidence of the advantages of sugammadex over neostigmine in high-risk and older patients undergoing prolonged, elective surgery. Here we consider the implications of the detailed statistical analysis used in these two studies and how its limitations could possibly have enhanced the statistical differences between the two drugs with respect to postoperative pulmonary complications.

A survey on the availability, usage and perception of neuromuscular monitors in Europe

PURPOSE

Neuromuscular blocking agents (NMBAs) are routinely administered to patients in a multiplicity of anesthetic settings. Absence of postoperative residual neuromuscular block is widely considered an anesthetic patient safety mandate. Despite the increasing availability of a wider range of commercial quantitative neuromuscular monitors, the availability and use of neuromuscular monitoring devices is deemed to be suboptimal even in countries with above-average health system ratings. The present study aims to more precisely characterize the perceived availability, cost sensitivity and usability of neuromuscular monitoring devices within European anesthesia departments.

METHODS

A pre-registered internet-based survey assessing the availability, cost sensitivity and usability of neuromuscular monitoring devices was distributed as e-mail newsletter by the European Society of Anaesthesiology and Intensive Care (ESAIC) to all of its active full members. The survey was available online for a total of 120 days.

RESULTS

Having targeted a total of 7472 ESAIC members, the survey was completed by a total of 692 anesthesiologists (9.3%) distributed across 37 different European countries. Quantitative monitors were reported to be proportionally more available than qualitative ones (87.6% vs. 62.6%, respectively), as well as in greater monitor-per-operating room ratios. Most anesthesiologists (60.5%) expressed moderate confidence in quantitative monitors, with artifactual recordings and inaccurate measurements being the most frequently encountered issues (25.9%). The commercial pricing of quantitative devices was considered more representative of a device's true value, when compared to qualitative instruments (average cost of €4.500 and €1.000 per device, respectively).

CONCLUSION

The availability of quantitative NMM in European operating theaters has increased in comparison with that reported in previous decades, potentially indicating increasing monitoring rates. European anesthesiologists express moderate confidence in quantitative neuromuscular monitors, along with a sentiment of adequate pricing when compared to their qualitative counterparts. Trust in quantitative monitors is marked by caution and awareness for artifactual recordings, with a consequent expectation that developments focusing on accuracy, reliability and ergonomics of neuromuscular monitors be prioritized.