The incidence and mechanisms of pharyngeal and upper esophageal dysfunction in partially paralyzed humans: pharyngeal videoradiography and simultaneous manometry after atracurium

The feasibility of the posterior tibial nerve-flexor hallucis brevis pathway applied in neuromuscular monitoring: a multicentric, controlled, and prospective clinical trial

This study aimed to investigate the clinical viability of utilizing the flexor hallucis brevis as an alternative site for neuromuscular monitoring compared to the conventional adductor pollicis. Patients were recruited from three medical centers. Cis-atracurium was administered, and two monitors were employed independently to assess neuromuscular blockade of the adductor pollicis and the ipsilateral flexor hallucis brevis, following a train of four (TOF) pattern until TOF ratios exceeded 0.9 or until the conclusion of surgery. Statistical analysis revealed significant differences in onset time, duration of no-twitch response, spontaneous recovery time, and total monitoring time between the two sites, with mean differences of -53.54 s, -2.49, 3.22, and 5.89 min, respectively (P < 0.001).The posterior tibial nerve-flexor hallucis brevis pathway presents a promising alternative for neuromuscular monitoring during anesthesia maintenance. Further investigation is warranted to explore its utility in anesthesia induction and recovery. Trial registration: The trial was registered at www.chictr.org.cn (20/11/2018, ChiCTR1800019651).

Under-dosing and over-dosing of neuromuscular blocking drugs and reversal agents: beware of the risks

The phenomena of residual curarisation and recurarisation after the use of long-acting non-depolarising neuromuscular blocking drugs such as tubocurarine and pancuronium were well recognised 60 years ago. But the incidence seemed to decline with the introduction of atracurium and vecuronium. However, recently there have been an increasing number of reports of residual and recurrent neuromuscular block. Some of these reports are a result of inappropriate doses of rocuronium, sugammadex or both, together with inadequate neuromuscular monitoring. We urge clinicians to review their practice to ensure the highest standards of clinical care when using neuromuscular blocking drugs and reversal agents. This includes the use of quantitative neuromuscular monitoring whenever neuromuscular blocking drugs are administered.

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.

Residual Neuromuscular Block Remains a Safety Concern for Perioperative Healthcare Professionals: A Comprehensive Review

Residual neuromuscular block (RNMB) remains a significant safety concern for patients throughout the perioperative period and is still widely under-recognized by perioperative healthcare professionals. Current literature suggests an association between RNMB and an increased risk of postoperative pulmonary complications, a prolonged length of stay in the post anesthesia care unit (PACU), and decreased patient satisfaction. The 2023 American Society of Anesthesiologists Practice Guidelines for Monitoring and Antagonism of Neuromuscular Blockade provide guidance for the use of quantitative neuromuscular monitoring coupled with neuromuscular reversal to recognize and reduce the incidence of RNMB. Using sugammadex for the reversal of neuromuscular block as well as quantitative neuromuscular monitoring to quantify the degree of neuromuscular block may significantly reduce the risk of RNMB among patients undergoing general anesthesia. Studies are forthcoming to investigate how using neuromuscular blocking agent reversal with quantitative monitoring of the neuromuscular block may further improve perioperative patient safety.

The effect of sugammadex on patient morbidity and quality of recovery after general anaesthesia: a systematic review and meta-analysis

BACKGROUND

Residual neuromuscular block is associated with increased patient morbidity. Therefore prevention of residual neuromuscular block is an important component of general anaesthesia where neuromuscular blocking agents are used. Whereas sugammadex improves reversal based on neuromuscular twitch monitoring parameters, there have been no prospective, adequately powered definitive studies demonstrating that sugammadex is also associated with less patient morbidity.

METHODS

We performed a systematic review of randomised trials comparing sugammadex with anticholinesterase-based reversal or placebo reversal that reported important patient outcomes beyond the postanaesthesia care unit.

RESULTS

We identified 43 articles, including 5839 trial participants. Only one trial reported days alive and out of hospital to 30 days (DAOH-30), which showed that the number of DAOH-30 was similar in those allocated to sugammadex compared with neostigmine-based reversal (25 days [19-27] vs 24 days [21-27], median difference 0.00 [-2.15 to 2.15]). Pooled analyses of data from 16 trials showed an estimated odds ratio (OR) for postoperative pulmonary complications of 0.67 (95% confidence interval 0.47-0.95) with sugammadex use. Pooled analysis showed that pneumonia (eight trials OR 0.51 [0.24-1.01] with sugammadex use), hospital length of stay (23 trials, mean difference -0.31 [-0.84 to 0.22] with sugammadex use), and patient-reported quality of recovery (11 trials, varied depending on metric used) are similar in those allocated to sugammadex vs control. The difference seen in mortality (11 trials, OR 0.39 [0.15-1.01] with sugammadex use) would be considered to be clinically significant and warrants further investigation, however, the rarity of these events precludes drawing definitive conclusions.

CONCLUSION

Although few trials reported on DAOH-30 or important patient outcomes, sugammadex is associated with a reduction in postoperative pulmonary complications, however, this might not translate to a difference in hospital length of stay, patient-reported quality of recovery, or mortality.

CLINICAL TRIAL REGISTRATION

PROSPERO database (CRD42022325858).

Efficacy and safety of adamgammadex for reversing rocuronium-induced deep neuromuscular blockade: A multicenter, randomized, phase IIb study

The rapid reversal of deep neuromuscular blockade (NMB) is important but remains challenging. This study aimed to evaluate the efficacy and safety of adamgammadex versus sugammadex in reversing deep rocuronium-induced NMB. This multicenter, randomized, phase IIb study included 80 patients aged 18-64 years, American Society of Anesthesiologists (ASA) grade 1-2, undergoing elective surgery under general anesthesia with rocuronium. Patients were randomized to the adamgammadex 7, 8, and 9 mg/kg group or the sugammadex 4 mg/kg group. The primary efficacy variable was the time to recovery of train-of-four ratio (TOFr) to 0.9. The secondary efficacy variables were the time to recovery of TOFr to 0.7, antagonistic success rate of the recovery of TOFr to 0.9 within 5 min, and incidence rate of recurarization within 30 min after drug administration. The explorative efficacy variable was the time to recovery of the corrected TOFr to 0.9 (actual/baseline TOF ratio). Adamgammadex 7, 8, and 9 mg/kg and sugammadex 4 mg/kg groups did not significantly differ in all efficacy variables. Importantly, adamgammadex 9 mg/kg permitted reversal within a geometric mean of 2.9 min. According to the safety profile, adamgammadex achieved good tolerance and low incidence of drug-related adverse events compared with the 4 mg/kg sugammadex. Adamgammadex 7, 8, and 9 mg/kg facilitated rapid reversal of deep rocuronium-induced NMB and had good tolerance and low incidence of drug-related adverse events. Therefore, adamgammadex is a potential and promising alternative to sugammadex.

Good clinical research practice (GCRP) in pharmacodynamic studies of neuromuscular blocking agents III: The 2023 Geneva revision

The set of guidelines for good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents was developed following an international consensus conference in Copenhagen in 1996 (Viby-Mogensen et al., Acta Anaesthesiol Scand 1996, 40, 59-74); the guidelines were later revised and updated following the second consensus conference in Stockholm in 2005 (Fuchs-Buder et al., Acta Anaesthesiol Scand 2007, 51, 789-808). In view of new devices and further development of monitoring technologies that emerged since then, (e.g., electromyography, three-dimensional acceleromyography, kinemyography) as well as novel compounds (e.g., sugammadex) a review and update of these recommendations became necessary. The intent of these revised guidelines is to continue to help clinical researchers to conduct high-quality work and advance the field by enhancing the standards, consistency, and comparability of clinical studies. There is growing awareness of the importance of consensus-based reporting standards in clinical trials and observational studies. Such global initiatives are necessary in order to minimize heterogeneous and inadequate data reporting and to improve clarity and comparability between different studies and study cohorts. Variations in definitions of endpoints or outcome variables can introduce confusion and difficulties in interpretation of data, but more importantly, it may preclude building of an adequate body of evidence to achieve reliable conclusions and recommendations. Clinical research in neuromuscular pharmacology and physiology is no exception.

Educating anaesthetists on neuromuscular monitoring: the challenges continue

The need to introduce guidelines on neuromuscular monitoring emphasising the use of quantitative techniques that record the train-of-four ratio is now recognised by an increasing number of national anaesthetic societies in the Western world. But the challenge of convincing individual anaesthetists to adopt and use this practice routinely remains. For >10 yr, it has been recognised that all staff in anaesthetic departments need to have regular training in modern neuromuscular monitoring techniques. We discuss a publication in this journal that describes the challenges of setting up multicentre training in Spain to expand the use of quantitative neuromuscular monitoring and their short-term results.

Optimal dose of neostigmine antagonizing cisatracurium-induced shallow neuromuscular block in elderly patients: a randomized control study

BACKGROUND

Residual neuromuscular block after using neuromuscular blocking agents is a common and potentially harmful complication of general anesthesia. Neostigmine is a widely used antagonist, but its optimal dose for elderly patients is unclear.

OBJECTIVES

To compare the optimal dosage and safety of neostigmine for reversing shallow residual block in elderly patients after cisatracurium-induced neuromuscular block.

METHODS

A randomized controlled trial was conducted in 196 elderly patients undergoing non-cardiac surgery under general anesthesia with cisatracurium. Patients were assigned to receive either no neostigmine (control group) or neostigmine at 20 µg/kg, 40 µg/kg or 50 µg/kg when train-of-four (TOF) ratio reached 0.2 at the end of surgery. The primary outcome was the time to reach TOF ratio of 0.9 after administration. Secondary outcomes included TOF ratio at 10 min after administration, postoperative nausea and vomiting, postoperative cognitive impairment and post-anesthesia care unit (PACU) stay time.

RESULTS

The time to reach TOF ratio of 0.9 in the 20 µg/kg, 40 µg/kg and 50 µg/kg groups was significantly shorter than the control group (H = 104.257, P < 0.01), and the time of 40 µg/kg group and 50 µg/kg group was significantly shorter than the 20 µg/kg group (P < 0.001). There was no significant difference between 40 µg/kg and 50 µg/kg groups (P = 0.249). The TOF ratio at 10 min after administration showed similar results. There were no significant differences among groups in postoperative nausea and vomiting, postoperative cognitive impairment or post-operation hospital stay.

CONCLUSIONS

Timely use of neostigmine after general anesthesia in elderly patients can significantly shorten time of TOF value reaching 0.9, among which 40 µg/kg dosage may be a more optimized choice.

TRIAL REGISTRATION

this study was registered on chictr.org.cn (ChiCTR2100054685, 24/12/2021).

Postoperative pulmonary complications after sugammadex reversal of neuromuscular blockade: a systematic review and meta-analysis with trial sequential analysis

BACKGROUND

Sugammadex has been reported to lower the incidence of postoperative residual neuromuscular blockade. Despite the advantages, until recently the effects of sugammadex on postoperative pulmonary complications (PPCs) were controversial. We conducted a systematic review and meta-analysis to determine whether reversal with sugammadex was associated with a lower risk of PPCs compared with neostigmine.

METHODS

PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched from inception to May 2022. Randomized controlled trials (RCTs) and observational studies comparing PPCs in patients receiving sugammadex or neostigmine as reversal agent at the end of surgery were included. The primary outcomes focused on PPCs including desaturation, pneumonia, atelectasis, noninvasive ventilation (NIV) and reintubation. Trial sequential analysis was performed on the primary outcomes to confirm whether firm evidence was reached.

RESULTS

Meta-analysis of included studies showed that the rate of desaturation (43.2% vs 45.0%, RR = 0.82; 95% CI 0.63 to 1.05; p = 0.11) were comparable between the two groups. When looking at other primary outcomes, significantly lower risk of pneumonia (1.37% vs 2.45%, RR = 0.65; 95% CI 0.49 to 0.85; p = 0.002), atelectasis (24.6% vs 30.4%, RR = 0.64; 95% CI 0.42 to 0.98; p = 0.04), NIV (1.37% vs 2.33%, RR = 0.65; 95% CI 0.43 to 0.98; p = 0.04) and reintubation (0.99% vs 1.65%, RR = 0.62; 95% CI 0.43 to 0.91; p = 0.01) in the sugammadex group were detected compared with the neostigmine group.

CONCLUSIONS

We concluded that sugammadex is more effective at reducing the incidence of PPCs including pneumonia, atelectasis, NIV and reintubation compared with neostigmine. Further evidence, preferably from RCTs, is required to confirm these findings.

Predictors of extubation failure in neurocritical patients: A systematic review

OBJECTIVE

The objective of this study was to identify predictors of extubation failure in neurocritical patients.

METHODS

This was systematic review performed through a bibliographic search of the databases PubMed/Medline, Lilacs, SciELO, and Web of Science, from February 2020 to October 2021. Cohort studies that investigated the predictors of extubation failure were included, defined as the need for reintubation within 48 h after extubation, in adult neurocritical patients. The risk-of-bias assessment was performed using the Newcastle-Ottawa Scale, for cohort studies.

RESULTS

Eight studies, totaling 18 487 participants, were included. A total of 15 predictors for extubation failure in neurocritical patients have been identified. Of these, four were the most frequent: low score on the Glasgow Coma Scale (motor score ≤5, 8T-10T), female gender, time on mechanical ventilation (≥7 days, ≥ 10 days), and moderate or large secretion volume.

CONCLUSIONS

In addition to the conventional parameters of weaning and extubation, other factors, such as a low score on the Glasgow Coma Scale, female gender, mechanical ventilation time, and moderate or large secretion volume, must be taken into account to prevent extubation failure in neurocritical patients in clinical practice.

Administration of enteral nutrition and gastrointestinal complications in Covid-19 critical patients in prone position

Background

The prone position (PP) used in the treatment of critically ill patients infected with SARS-CoV-2, may be a barrier to enteral nutrition (EN). This study aimed to analyze the effectiveness and complications of EN in the PP, as well as clinical outcomes.

Methods

Prospective cohort study with patients in EN and coronavirus disease 2019 (COVID-19), on mechanical ventilation (MV), which whom needed or not PP. Gastrointestinal intolerances (GII) related to PP were evaluated, and correlated with possible confounding factors. EN, days on MV, Intensive Care Unit (ICU) length of stay, hospital length of stay, ventilator-associated pneumonia (VAP) and mortality were analyzed. The data were evaluated daily and compared prone group (PG=57) and supine group (SG=69).

Results

The PP was associated with GII (P=0.000) and presented in 32 patients (26,44%) with no difference among groups. Association between epinephrine (P=0.003), vasopressin (P=0.018), and GII was observed. There was no difference between the total volume of enteral nutrition (TVEN) infused in the groups. However, the mean EN infused for the days when the patient was on PP was (70.0% ± 31.5) and for the days in supine position was (74.8% ± 27.3), P= 0.006. The PG had a longer time on MV (P=0.005) and ICU (P=0.003) and PP was associated with VAP (P=<0.001). The infused TVEN showed no association with VAP (P=0.09).

Conclusion

PP was a determining factor in GII and proved to be a risk factor for VAP, but the EN protocol seems to have ensured an adequate EN supply in PP and be a safe alternative.

Optimizing Reversal of Neuromuscular Block in Older Adults: Sugammadex or Neostigmine

Residual neuromuscular paralysis, the presence of clinically significant weakness after administration of pharmacologic neuromuscular blockade reversal, is associated with postoperative pulmonary complications and is more common in older patients. In contemporary anesthesia practice, reversal of neuromuscular blockade is accomplished with neostigmine or sugammadex. Neostigmine, an acetylcholinesterase inhibitor, increases the concentration of acetylcholine at the neuromuscular junction, providing competitive antagonism of neuromuscular blocking drug and facilitating muscle contraction. Sugammadex, a modified gamma-cyclodextrin, antagonizes neuromuscular blockade by encapsulating rocuronium and vecuronium in a one-to-one ratio for renal clearance, a pharmacokinetic property that led to the recommendation that sugammadex not be administered to those with end-stage renal disease. While data are limited, reports suggest sugammadex is efficacious and well tolerated in individuals with reduced renal function. Sugammadex provides a more rapid and complete reversal of neuromuscular blockade than neostigmine. There is also accumulating evidence that sugammadex may provide a protective effect against the development of postoperative pulmonary complications, nausea, and vomiting, and that it may have beneficial effects on the rate of bowel and bladder recovery after surgery. Accordingly, sugammadex administration is beneficial for most older patients undergoing surgery.

Efficacy and Safety of Sugammadex versus Neostigmine in Reversing Neuromuscular Blockade in Morbidly Obese Adult Patients: A Systematic Review and Meta-Analysis

Context:

Sugammadex is known to reverse neuromuscular blockade (NMB) more rapidly and reliably than neostigmine. However, data remain limited in bariatric patients. In this review, we systematically evaluated the efficacy and safety of sugammadex versus neostigmine in reversing NMB in morbidly obese (MO) patients undergoing bariatric surgery.

Aims:

Our primary objective was to determine the recovery time from drug administration to a train-of-four (TOF) ratio >0.9 from a moderate or deep NMB.

Settings and Design:

This systematic review and meta-analysis (SR and MA) was conducted in accordance with the Preferred Items for SRs and MAs guidelines.

Subjects and Methods:

A systematic search was conducted within multiple databases for studies that compared sugammadex and neostigmine in MO patients.

Statistical Analysis Used:

We reported data as mean difference (MD) or odds ratios (OR) and corresponding 95% confidence interval (CI) using random-effects models. A two-sided P < 0.05 was considered statistically significant.

Results:

Seven studies with 386 participants met the inclusion criteria. Sugammadex significantly reduced the time of reversal of moderate NMB-to-TOF ratio >0.9 compared to neostigmine, with a mean time of 2.5 min (standard deviation [SD] 1.25) versus 18.2 min (SD 17.6), respectively (MD: −14.52; 95% CI: −20.08, −8.96; P < 0.00001; I² = 96%). The number of patients who had composite adverse events was significantly lower with sugammadex (21.2% of patients) compared to neostigmine (52.5% of patients) (OR: 0.15; 95% CI: 0.07–0.32; P < 0.00001; I² = 0%).

Conclusions:

Sugammadex reverses NMB more rapidly with fewer adverse events than neostigmine in MO patients undergoing bariatric surgery.

Efficiency and Safety of the Selective Relaxant Binding Agent Adamgammadex Sodium for Reversing Rocuronium-Induced Deep Neuromuscular Block: A Single-Center, Open-Label, Dose-Finding, and Phase IIa Study

Background: Rapid reversal of neuromuscular block after surgery and anesthesia is often necessary. Here, we reported the primary efficacy and safety data from a phase IIa study on adamgammadex sodium, a newly developed modified γ-cyclodextrin derivative.

Methods: This was a phase IIa, single-center, randomized, open-label, and dose-finding study that enrolled 35 patients under general anesthesia who received the neuromuscular blocking agent rocuronium for induction and maintenance of neuromuscular blockade. The subjects were randomized to one of the five adamgammadex dose groups (2, 4, 6, 8, and 10 mg kg⁻¹) and to the 4 mg kg⁻¹ sugammadex group. Pharmacological efficacy was the recovery time from the start of adamgammadex or sugammadex administration to train-of-four (TOF) ratio ≥0.9, 0.8, and 0.7 among the different dose groups. Adverse events were recorded throughout the study.

Results: The efficacy in reversing deep neuromuscular block was the same between 4 mg kg⁻¹ sugammadex and adamgammadex. However, in the lowest dose groups of 2 and 4 mg kg⁻¹ adamgammadex, adequate reversal could not be achieved in all subjects. The recovery time of TOF ratio to 0.9, 0.8, and 0.7 was shorter in the adamgammadex 10 mg kg⁻¹ group than in the sugammadex 4 mg kg⁻¹ group. The average values of the TOF ratio after 3 min of administration of adamgammadex 8 and 10 mg kg⁻¹ and sugammadex 4 mg kg⁻¹ were >90%. There were no serious adverse events after the use of adamgammadex, and no subjects had to be withdrawn from the trial.

Conclusions: Adamgammadex enabled quick, predictable, and tolerable reversion of rocuronium-induced deep neuromuscular block in a dose-dependent manner. Adamgammadex doses of 6–10 mg kg⁻¹ might be the recommended dose range for further exploration of efficacy. Clinical Trial Registration: This study was registered at chictr.org.cn, identifier: ChiCTR2000038391.

Recovery of lower oesophageal barrier function: a pilot study comparing a mixture of atropine and neostigmine and sugammadex: A randomised controlled pilot study

BACKGROUND

The lower oesophageal sphincter (LOS) barrier serves to prevent regurgitation of gastric contents. Although general anaesthesia depresses its function, its recovery process during emergence from anaesthesia has not been systematically examined.

OBJECTIVE

To explore whether recovery of lower oesophageal barrier function differed between patients receiving a mixture of 1 mg atropine and 2 mg neostigmine and those receiving 2 mg kg-1 sugammadex during emergence from anaesthesia.

DESIGN

An unblinded randomised controlled pilot study.

SETTING

A single university hospital from January 2016 to December 2018.

PATIENTS

A total of 20 non-obese adult females undergoing minor surgery.

INTERVENTION

The patients were randomly assigned to a group either receiving atropine and neostigmine or sugammadex for reversal of rocuronium.

MAIN OUTCOME MEASURES

Through use of the high-resolution manometry technique, the lower oesophageal barrier pressure (PBAR: primary variable) defined as a pressure difference between pressures at the LOS and the stomach was measured at five distinguishable time points during emergence from total intravenous anaesthesia. A mixed effects model for repeated measures was used to test the hypothesis.

RESULTS

In all patients baseline PBAR values were positive even under muscle paralysis and general anaesthesia before administration of reversal agents, and did not differ between the groups (P = 0.299). During recovery from muscle paralysis and general anaesthesia, PBAR (mean ± SD) significantly increased (P = 0.004) from 17.0 ± 2.9 to 21.0 ± 5.0 mmHg in the atropine and neostigmine group (n = 8) and from 19.1 ± 9.0 to 24.5 ± 12.7 mmHg in the sugammadex group (n = 11). PBAR significantly increased immediately after return of consciousness in both groups, whereas return of muscle tone, lightening of anaesthesia and tracheal extubation did not change it.

CONCLUSION

Recovery of the lower oesophageal barrier function does not differ between patients receiving either atropine and neostigmine or sugammadex and is completed after recovery of consciousness from general anaesthesia.

TRIAL REGISTRATION

UMIN Clinical Trials Registry: UMIN000020500: https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=brows&action=brows&recptno=R000023594&type=summary&language=E.

Postoperative Pulmonary Complications' Association with Sugammadex versus Neostigmine: A Retrospective Registry Analysis

BACKGROUND

Postoperative residual neuromuscular blockade related to nondepolarizing neuromuscular blocking agents may be associated with pulmonary complications. In this study, the authors sought to determine whether sugammadex was associated with a lower risk of postoperative pulmonary complications in comparison with neostigmine.

METHODS

Adult patients from the Vanderbilt University Medical Center National Surgical Quality Improvement Program database who underwent general anesthesia procedures between January 2010 and July 2019 were included in an observational cohort study. In early 2017, a wholesale switch from neostigmine to sugammadex occurred at Vanderbilt University Medical Center. The authors therefore identified all patients receiving nondepolarizing neuromuscular blockades and reversal with neostigmine or sugammadex. An inverse probability of treatment weighting propensity score analysis approach was applied to control for measured confounding. The primary outcome was postoperative pulmonary complications, determined by retrospective chart review and defined as the composite of the three postoperative respiratory occurrences: pneumonia, prolonged mechanical ventilation, and unplanned intubation.

RESULTS

Of 10,491 eligible cases, 7,800 patients received neostigmine, and 2,691 received sugammadex. A total of 575 (5.5%) patients experienced postoperative pulmonary complications (5.9% neostigmine vs. 4.2% sugammadex). Specifically, 306 (2.9%) patients had pneumonia (3.2% vs. 2.1%), 113 (1.1%) prolonged mechanical ventilation (1.1% vs. 1.1%), and 156 (1.5%) unplanned intubation (1.6% vs. 1.0%). After propensity score adjustment, the authors found a lower absolute incidence rate of postoperative pulmonary complications over time (adjusted odds ratio, 0.91 [per year]; 95% CI, 0.87 to 0.96; P < .001). No difference was observed on the odds of postoperative pulmonary complications in patients receiving sugammadex in comparison with neostigmine (adjusted odds ratio, 0.89; 95% CI, 0.65 to 1.22; P = 0.468).

CONCLUSIONS

Among 10,491 patients at a single academic tertiary care center, the authors found that switching neuromuscular blockade reversal agents was not associated with the occurrence of postoperative pulmonary complications.

EDITOR’S PERSPECTIVE

Vigilance: the behavioral impact of quantitative monitoring on administration and antagonism of neuromuscular blocking agents

PURPOSE

The aim of this study was to determine whether use of acceleromyography (1) changes dosing of neuromuscular blocking agents (NMBAs), and (2) increases the time between neostigmine administration and extubation, when compared with subjective assessment of neuromuscular blockade.

METHODS

For this retrospective study, data were collected from patient electronic medical records. Patients were included if they had received an NMBA as part of a general anesthetic in 2013 and 2014. Data were analyzed by category of monitoring device: quantitative monitor (acceleromyograph [AMG]) or subjective device (peripheral nerve stimulator [PNS]). Outcomes measured were the total dose of NMBA administered and, the timing of the last dose of NMBA and anticholinesterase relative to tracheal extubation.

RESULTS

Results from multivariate models showed that use of acceleromyography was not associated with a change in the total dose of NMBA administered. In contrast, the number of times any monitor was used, as determined by the frequency with which the train-of-four count (TOFC) was recorded, correlated with the administration of greater amounts of rocuronium (P < 0.01) and vecuronium (P < 0.01). The use of acceleromyography did not prolong the time interval between neostigmine administration and tracheal extubation. The number of times any monitor was used during an anesthetic was associated with a decrease in this time interval. The interval decreased an average of 2.7 min each successive time the TOFC was recorded (P < 0.01).

CONCLUSIONS

The data presented provides insight about the behavioral engineering inherent to the practice of anesthesiology. Introduction of neuromuscular blockade assessment appeared to increase provider vigilance in dosing of NMBAs-regardless of assessment method. The frequency of intraoperative monitoring (quantitative or subjective) was associated with an increased total dose of NMBA administered and decreased time interval between the last dose of neostigmine and extubation.

Exploratory Outlier Detection for Acceleromyographic Neuromuscular Monitoring: Machine Learning Approach

Background

Perioperative quantitative monitoring of neuromuscular function in patients receiving neuromuscular blockers has become internationally recognized as an absolute and core necessity in modern anesthesia care. Because of their kinetic nature, artifactual recordings of acceleromyography-based neuromuscular monitoring devices are not unusual. These generate a great deal of cynicism among anesthesiologists, constituting an obstacle toward their widespread adoption. Through outlier analysis techniques, monitoring devices can learn to detect and flag signal abnormalities. Outlier analysis (or anomaly detection) refers to the problem of finding patterns in data that do not conform to expected behavior.

Objective

This study was motivated by the development of a smartphone app intended for neuromuscular monitoring based on combined accelerometric and angular hand movement data. During the paired comparison stage of this app against existing acceleromyography monitoring devices, it was noted that the results from both devices did not always concur. This study aims to engineer a set of features that enable the detection of outliers in the form of erroneous train-of-four (TOF) measurements from an acceleromyographic-based device. These features are tested for their potential in the detection of erroneous TOF measurements by developing an outlier detection algorithm.

Methods

A data set encompassing 533 high-sensitivity TOF measurements from 35 patients was created based on a multicentric open label trial of a purpose-built accelero- and gyroscopic-based neuromuscular monitoring app. A basic set of features was extracted based on raw data while a second set of features was purpose engineered based on TOF pattern characteristics. Two cost-sensitive logistic regression (CSLR) models were deployed to evaluate the performance of these features. The final output of the developed models was a binary classification, indicating if a TOF measurement was an outlier or not.

Results

A total of 7 basic features were extracted based on raw data, while another 8 features were engineered based on TOF pattern characteristics. The model training and testing were based on separate data sets: one with 319 measurements (18 outliers) and a second with 214 measurements (12 outliers). The F1 score (95% CI) was 0.86 (0.48-0.97) for the CSLR model with engineered features, significantly larger than the CSLR model with the basic features (0.29 [0.17-0.53]; P<.001).

Conclusions

The set of engineered features and their corresponding incorporation in an outlier detection algorithm have the potential to increase overall neuromuscular monitoring data consistency. Integrating outlier flagging algorithms within neuromuscular monitors could potentially reduce overall acceleromyography-based reliability issues.

Trial Registration

ClinicalTrials.gov NCT03605225; https://clinicaltrials.gov/ct2/show/NCT03605225

Ease of Application of Various Neuromuscular Devices for Routine Monitoring

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Actual versus ideal body weight dosing of sugammadex in morbidly obese patients offers faster reversal of rocuronium- or vecuronium-induced deep or moderate neuromuscular block: a randomized clinical trial

Background

This randomized, double-blind trial evaluated sugammadex-mediated recovery time from rocuronium- or vecuronium-induced moderate (M-) or deep (D-) neuromuscular block in morbidly obese adults dosed by actual (ABW) or ideal body weight (IBW).

Methods

Adults with BMI ≥40 kg/m² were randomized to 1 of 5 groups: M-neuromuscular block, sugammadex 2 mg/kg ABW; M-neuromuscular block, sugammadex 2 mg/kg IBW; M-neuromuscular block, neostigmine 5 mg, and glycopyrrolate 1 mg; D-neuromuscular block, sugammadex 4 mg/kg ABW; or D-neuromuscular block, sugammadex 4 mg/kg IBW. Supramaximal train of four (TOF) stimulation of the ulnar nerve (TOF-watch SX®) monitored recovery. Primary endpoint was time to TOF ratio ≥ 0.9 for ABW and IBW groups pooled across neuromuscular blocking agent (NMBA)/blocking depth, analyzed by log-rank test stratified for agent and depth. Prespecified safety outcomes included treatment-emergent bradycardia, tachycardia, and other arrhythmias, and adjudicated hypersensitivity and anaphylaxis.

Results

Of 207 patients randomized, 188 received treatment (28% male, BMI 47 ± 5.1 kg/m², age 48 ± 13 years). Recovery was 1.5 min faster with ABW vs IBW dosing. The sugammadex 2 mg/kg groups recovered 9-fold faster [time 0.11-fold, 95% CI 0.08 to 0.14] than the neostigmine group. ABW (5.3%) and IBW (2.7%) groups had similar incidences of recovery time > 10 min (95% CI of difference: − 4.8 to 11.0%); 84% for neostigmine group. Re-curarization occurred in one patient each in the 2 mg/kg IBW and neostigmine groups. Prespecified safety outcomes occurred with similar incidences.

Conclusions

ABW-based sugammadex dosing yields faster reversal without re-curarization, supporting ABW-based sugammadex dosing in the morbidly obese, irrespective of the depth of neuromuscular block or NMBA used.

Trial registration

Registered on November 17, 2017, at ClinicalTrials.gov under number NCT03346070.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01278-w.

Economic impact of improving patient safety using Sugammadex for routine reversal of neuromuscular blockade in Spain

Background

Neuromuscular blocking (NMB) agents are often administered to facilitate tracheal intubation and prevent patient movement during surgical procedures requiring the use of general anesthetics. Incomplete reversal of NMB, can lead to residual NMB, which can increase the risk of post-operative pulmonary complications. Sugammadex is indicated to reverse neuromuscular blockade induced by rocuronium or vecuronium in adults. The aim of this study is to estimate the clinical and economic impact of introducing sugammadex to routine reversal of neuromuscular blockade (NMB) with rocuronium in Spain.

Methods

A decision analytic model was constructed reflecting a set of procedures using rocuronium that resulted in moderate or deep NMB at the end of the procedure. Two scenarios were considered for 537,931 procedures using NMB agents in Spain in 2015: a scenario without sugammadex versus a scenario with sugammadex. Comparators included neostigmine (plus glycopyrrolate) and no reversal agent. The total costs for the healthcare system were estimated from the net of costs of reversal agents and overall cost offsets via reduction in postoperative pneumonias and atelectasis for which incidence rates were based on a Spanish real-world evidence (RWE) study. The model time horizon was assumed to be one year. Costs were expressed in 2019 euros (€) and estimated from the perspective of a healthcare system. One-way sensitivity analysis was carried out by varying each parameter included in the model within a range of +/− 50%.

Results

The estimated budget impact of the introduction of sugammadex to the routine reversal of neuromuscular blockade in Spanish hospitals was a net saving of €57.1 million annually. An increase in drug acquisition costs was offset by savings in post-operative pulmonary events, including 4806 post-operative pneumonias and 13,996 cases of atelectasis. The total cost of complications avoided was €70.4 million. All parameters included in the model were tested in sensitivity analysis and were favorable to the scenario with sugammadex.

Conclusions

This economic analysis shows that sugammadex can potentially lead to cost savings for the reversal of rocuronium-induced moderate or profound NMB compared to no reversal and reversal with neostigmine in the Spanish health care setting. The economic model was based on data obtained from Spain and from assumptions from clinical practice and may not be valid for other countries.

Cholinergic Chemotransmission and Anesthetic Drug Effects at the Carotid Bodies

General anesthesia is obtained by administration of potent hypnotics, analgesics and muscle relaxants. Apart from their intended effects (loss of consciousness, pain relief and muscle relaxation), these agents profoundly affect the control of breathing, in part by an effect within the peripheral chemoreflex loop that originates at the carotid bodies. This review assesses the role of cholinergic chemotransmission in the peripheral chemoreflex loop and the mechanisms through which muscle relaxants and hypnotics interfere with peripheral chemosensitivity. Additionally, consequences for clinical practice are discussed.

Economic analysis of sugammadex versus neostigmine for reversal of neuromuscular blockade for laparoscopic surgery in China

BACKGROUND

Neuromuscular blockade and pneumoperitoneum (PP) are important factors to ensure successful laparoscopic surgery. However, residual neuromuscular blockade (rNMB) and PP are associated with many unfavorable complications. The aim of this study is to compare the cost-effectiveness of using sugammadex versus neostigmine in laparoscopic surgery in China.

METHODS

A decision tree model was developed with a time horizon based on laparoscopic surgery related hospitalization duration. 2000 patients using sugammadex or neostigmine were simulated within the model. The model outcomes included incidence of rNMB and PP related complications and their treatment costs. Data on clinical efficacy, safety and cost were collected from published literature and interviews of physicians.

RESULTS

The model projected that treatment with sugammadex instead of neostigmine would lead to 673 fewer total complications, including rNMB/PP related complications, hospitalization, and other AEs (621 events versus 1294 events, respectively). Use of sugammadex was associated with an incremental medication cost of ¥1,360,410. However, 93.6% of the increased medication cost can be off-set by the reduced costs attributable to treatment of rNMB related complications, PP related complications, hospitalization and other adverse events in sugammadex group. In aggregate, the sugammadex group incurred an incremental cost of ¥86,610 to prevent 673 complications, (¥128.56 per one rNMB/PP related complications prevention). One-way sensitivity analysis confirmed the robustness of the model.

CONCLUSIONS

Use of sugammadex in replacement of neostigmine would result in significantly lower rNMB/PP related complications but at a substantially higher medication cost. Upon accounting for the costs associated with treatment of rNMB/PP related complications, 93.6% of medication cost is projected to be offset. In balance, sugammadex appears to offer good value for reversal of neuromuscular blockade for laparoscopic surgery in China.

Electroacupuncture Involved in Motor Cortex and Hypoglossal Neural Control to Improve Voluntary Swallowing of Poststroke Dysphagia Mice

The descending motor nerve conduction of voluntary swallowing is mainly launched by primary motor cortex (M1). M1 can activate and regulate peripheral nerves (hypoglossal) to control the swallowing. Acupuncture at “Lianquan” acupoint (CV23) has a positive effect against poststroke dysphagia (PSD). In previous work, we have demonstrated that electroacupuncture (EA) could regulate swallowing-related motor neurons and promote swallowing activity in the essential part of central pattern generator (CPG), containing nucleus ambiguus (NA), nucleus of the solitary tract (NTS), and ventrolateral medulla (VLM) under the physiological condition. In the present work, we have investigated the effects of EA on the PSD mice in vivo and sought evidence for PSD improvement by electrophysiology recording and laser speckle contrast imaging (LSCI). Four main conclusions can be drawn from our study: (i) EA may enhance the local field potential in noninfarction area of M1, activate the swallowing-related neurons (pyramidal cells), and increase the motor conduction of noninfarction area in voluntary swallowing; (ii) EA may improve the blood flow in both M1 on the healthy side and deglutition muscles and relieve PSD symptoms; (iii) EA could increase the motor conduction velocity (MCV) in hypoglossal nerve, enhance the EMG of mylohyoid muscle, alleviate the paralysis of swallowing muscles, release the substance P, and restore the ability to drink water; and (iv) EA can boost the functional compensation of M1 in the noninfarction side, strengthen the excitatory of hypoglossal nerve, and be involved in the voluntary swallowing neural control to improve PSD. This research provides a timely and necessary experimental evidence of the motor neural regulation in dysphagia after stroke by acupuncture in clinic.

Efficacy and Safety of Neuromuscular Blockade in Overweight Patients Undergoing Nasopharyngeal Surgery

BACKGROUND Adequate muscle relaxation and rapid recovery of neuromuscular function are essential in the perioperative period. We therefore compared various anesthetic regimens of neuromuscular blockers and antagonists administered to overweight patients undergoing nasopharyngeal surgery. MATERIAL AND METHODS This prospective, randomized, double-blind study was conducted in overweight patients undergoing nasopharyngeal surgery. We randomly assigned 102 patients into 3 groups (each n=34) treated with various muscle relaxant agents and antagonists: rocuronium and sugammadex (Group RS), rocuronium and neostigmine (Group RN), and cisatracurium and neostigmine (Group CN). Then, we compared the efficacy and safety indexes of the 3 groups. RESULTS Onset times of muscular relaxation in Group RS and Group RN (110 s and 120 s) were shorter than in Group CN (183 s). Time from administration of antagonist to recovery of the TOF ratio to 0.9 was shorter in Group RS (3.3 min) than in other groups (20.7 min and 19.1 min, respectively). The incidence of postoperative residual curarization (PORC) was significantly lower in Group RS (5.9%) than in the other 2 groups (both 41.2%). The hemodynamic parameter changes before extubation were significantly higher in Group RN and Group CN than in Group RS. The postoperative pain scores were lowest in Group RS. CONCLUSIONS For overweight patients undergoing nasopharyngeal surgery, the use of rocuronium with sugammadex had the shortest onset time of neuromuscular relaxation, accelerated the reversion of neuromuscular blockade, effectively reduced the occurrence of PORC, relieved postoperative pain, and maintained hemodynamic stability before extubation. The combination of rocuronium and sugammadex may be the best anesthetic regimen for overweight patients undergoing nasopharyngeal surgery.

Residual Neuromuscular Blockade and Postoperative Pulmonary Complications: What Does the Recent Evidence Demonstrate?

Purpose of Review

The purpose of this review is to assess how residual neuromuscular block impacts postoperative pulmonary complications and whether we can modify the risk by improving certain aspects in daily clinical care.

Recent findings

Postoperative respiratory impairment may be due to various causes, such as age, surgery type, comorbidity, smoking, preoperative anemia, and general anesthesia. However, increasing evidence suggests that residual neuromuscular block is an important risk factor for postoperative pulmonary complications and may affect the outcome. Conflicting data from some recent reports show that the use of quantitative neuromuscular monitoring alone does not preclude residual neuromuscular block and that improvements in the interpretation of neuromuscular monitoring may be required. Pulmonary complications seem to be reduced for train-of-four ratios > 0.95 before tracheal extubation compared with > 0.9.

Summary

This review stresses the need for appropriate management of neuromuscular block in the prevention of postoperative pulmonary complications but acknowledges that the causes are multifactorial.

SUGAMMADEX versus neostigmine after ROCURONIUM continuous infusion in patients undergoing liver transplantation

BACKGROUND

Rapid neuromuscular block reversal at the end of major abdominal surgery is recommended to avoid any postoperative residual block. To date, no study has evaluated sugammadex performance after rocuronium administration in patients undergoing liver transplantation. This is a randomized controlled trial with the primary objective of assessing the neuromuscular transmission recovery time obtained with sugammadex versus neostigmine after rocuronium induced neuromuscular blockade in patients undergoing orthotopic liver transplantation.

METHODS

The TOF-Watch SX®, calibrated and linked to a portable computer equipped with TOF-Watch SX Monitor Software®, was used to monitor and record intraoperative neuromuscular block maintained with a continuous infusion of rocuronium. Anaesthetic management was standardized as per our institution's internal protocol. At the end of surgery, neuromuscular moderate block reversal was obtained by administration of 2 mg/kg of sugammadex or 50 mcg/kg of neostigmine (plus 10 mcg/kg of atropine).

RESULTS

Data from 41 patients undergoing liver transplantation were analysed. In this population, recovery from neuromuscular block was faster following sugammadex administration than neostigmine administration, with mean times±SD of 9.4 ± 4.6 min and 34.6 ± 24.9 min, respectively (p < 0.0001).

CONCLUSION

Sugammadex is able to reverse neuromuscular block maintained by rocuronium continuous infusion in patients undergoing liver transplantation. The mean reversal time obtained with sugammadex was significantly faster than that for neostigmine. It is important to note that the sugammadex recovery time in this population was found to be considerably longer than in other surgical settings, and should be considered in clinical practice.

TRIAL REGISTRATION

ClinicalTrials.govNCT02697929 (registered 3rd March 2016).

Comparison of sugammadex and pyridostigmine bromide for reversal of rocuronium-induced neuromuscular blockade in short-term pediatric surgery: A prospective randomized study

BACKGROUND

Sugammadex reverses rocuronium-induced neuromuscular blockade quickly and effectively. This study compared efficacy of sugammadex and pyridostigmine for reversal of rocuronium-induced light block or minimal block in children scheduled for elective entropion surgery.

METHODS

A prospective randomized study was conducted on 60 pediatric patients aged 1 to 11 years and scheduled for entropion surgery under sevoflurane anesthesia. Neuromuscular blockade was achieved by administration of 0.6 mg/kg rocuronium and assessed using train-of-four (TOF) ulnar nerve stimulation. Patients were randomly assigned to 2 groups receiving sugammadex 2 mg/kg or pyridostigmine 0.2 mg/kg plus glycopyrrolate 0.01 mg/kg. Primary outcomes were time from reversal agents administration to TOF ratio 0.9 and time from reversal agent administration to TOF ratio 1.0. Time from TOF ratio 0.9 to extubation, time from TOF ratio 1.0 to extubation, and postoperative adverse events were also recorded.

RESULTS

There were no substantial differences in demographic variables. Time from reversal agents administration to TOF ratio 0.9 and time from reversal agents to TOF ratio 1.0 were significantly faster in sugammadex group: 1.30 ± 0.84 versus 3.53 ± 2.73 minutes (P < .001) and 2.75 ± 1.00 versus 5.73 ± 2.83 minutes (P < .001). Extubation time was shorter in sugammadex group. Incidence of skin rash, nausea, vomiting, and postoperative residual neuromuscular blockade (airway obstruction) was not statistically different between groups. Incidence of patients agitation in recovery room was lower in sugammadex group.

CONCLUSION

Sugammadex provided more rapid reversal of rocuronium-induced neuromuscular blockade in pediatric patients undergoing surgery lasting 30 to 60 minutes than did pyridostigmine plus glycopyrrolate, with no differences in incidence of adverse events between groups.

Audit of peripheral neuromuscular stimulators at the hospitals staffed by the Department of Anaesthesia and Perioperative Medicine at the University of Cape Town

Background: Inadequate monitoring of neuromuscular blockade (NMB) may result in worse patient outcomes, including airway compromise and postoperative pulmonary complications. Therefore, NMB monitor availability is a minimum requirement for perioperative care according to the South African Society of Anaesthesiologists’ (SASA) 2018 guidelines. The authors performed an audit of peripheral nerve stimulators (PNS) functionality and availability at their institution. Methods: The PNSs were attached to an electrical circuit with a skin equivalent resistance. The resultant current impulses generated using Train-of-Four (TOF) mode and Double Burst Stimulation (DBS) mode were recorded with a voltage scope meter. PNS availability was assessed in theatre and recovery areas. Results: Of the 65 PNS units assessed, 39 units were dysfunctional and 26 units fully functional. The most frequent fault found (30 units) related to faulty or absent PNS electrode cables. Eight functional PNS units with TOF ratio display capability were found. The working PNSs showed good inter-device peak voltage measurement correlation. Of the 59 areas identified where PNSs should be easily available, only 37 areas met the PNS availability criteria suggested in the SASA guidelines. Conclusion: This audit highlighted the need for more new generation PNSs with TOF-ratio-display-ability to align the institution with recommendations from SASA standards and the anaesthetic literature. It also highlighted the accuracy and consistency of delivered current bursts by the working PNS devices.

Survey of neuromuscular monitoring and assessment of postoperative residual neuromuscular block in a postoperative anaesthetic care unit

INTRODUCTION

The use of neuromuscular blocking agents (NMBAs) is common during general anaesthesia. Neuromuscular monitoring with a peripheral nerve stimulator (PNS) is essential to prevent postoperative residual neuromuscular block (PRNB), defined as a train-of-four (TOF) ratio < 0.9. PRNB remains a common complication and may contribute to morbidity in the postoperative anaesthetic care unit (PACU).

METHODS

An online survey was sent to anaesthesiologists in our department to assess their knowledge and clinical practices related to neuromuscular blockade. Next, a study was conducted on adult patients scheduled for elective surgery under general anaesthesia requiring NMBAs. Upon admission to the PACU, TOF monitoring was performed.

RESULTS

A large proportion of anaesthesiologists showed a lack of knowledge of neuromuscular blockade or non-adherence to the best clinical practices associated with it. The majority (98.7%) stated that they did not routinely use PNS monitoring. In the clinical study, TOF monitoring was only used in 17.9% of the 335 patients who were assessed. The prevalence of PRNB was 33.4% and was associated with the elderly (age ≥ 65 years), a higher dose of NMBA used, a shorter duration of surgery, and a shorter duration between the last dose of NMBA and measurement of PRNB in the PACU. The incidence of adverse symptoms in the PACU was observed to be higher in patients with PRNB.

CONCLUSION

PRNB remains a clinically significant problem, but routine PNS monitoring is rare in our institution. This is compounded by inadequate knowledge and poor adherence to best clinical guidelines related to neuromuscular blockade.

Reversal of Partial Neuromuscular Block and the Ventilatory Response to Hypoxia

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

The ventilatory response to hypoxia is a life-saving chemoreflex originating at the carotid bodies that is impaired by nondepolarizing neuromuscular blocking agents. This study evaluated the effect of three strategies for reversal of a partial neuromuscular block on ventilatory control in 34 healthy male volunteers on the chemoreflex. The hypothesis was that the hypoxic ventilatory response is fully restored following the return to a train-of-four ratio of 1.

Methods

In this single-center, experimental, randomized, controlled trial, ventilatory responses to 5-min hypoxia (oxygen saturation, 80 ± 2%) and ventilation at hyperoxic isohypercapnia (end-tidal carbon dioxide concentration, 55 mmHg) were obtained at baseline, during rocuronium-induced partial neuromuscular block (train-of-four ratio of 0.7 measured at the adductor pollicis muscle by electromyography), and following reversal until the train-of-four ratio reached unity with placebo (n = 12), 1 mg neostigmine/0.5 mg atropine (n = 11), or 2 mg/kg sugammadex (n = 11).

Results

This study confirmed that low-dose rocuronium reduced the ventilatory response to hypoxia from 0.55 ± 0.22 (baseline) to 0.31 ± 0.21 l · min−1 · %−1 (train-of-four ratio, 0.7; P &lt; 0.001). Following full reversal as measured at the thumb, there was persistent residual blunting of the hypoxic ventilatory response (0.45 ± 0.16 l · min−1 · %−1; train-of-four ratio, 1.0; P &lt; 0.001). Treatment effect was not significant (analysis of covariance, P = 0.299) with chemoreflex impairment in 5 (45%) subjects following sugammadex reversal, in 7 subjects (64%) following neostigmine reversal, and in 10 subjects (83%) after spontaneous reversal to a train-of-four ratio of 1.

Conclusions

Despite full reversal of partial neuromuscular block at the thumb, impairment of the peripheral chemoreflex may persist at train-of-four ratios greater than 0.9 following reversal with neostigmine and sugammadex or spontaneous recovery of the neuromuscular block.

Consensus Statement on Perioperative Use of Neuromuscular Monitoring

A panel of clinician scientists with expertise in neuromuscular blockade (NMB) monitoring was convened with a charge to prepare a consensus statement on indications for and proper use of such monitors. The aims of this article are to: (a) provide the rationale and scientific basis for the use of quantitative NMB monitoring; (b) offer a set of recommendations for quantitative NMB monitoring standards; (c) specify educational goals; and (d) propose training recommendations to ensure proper neuromuscular monitoring and management. The panel believes that whenever a neuromuscular blocker is administered, neuromuscular function must be monitored by observing the evoked muscular response to peripheral nerve stimulation. Ideally, this should be done at the hand muscles (not the facial muscles) with a quantitative (objective) monitor. Objective monitoring (documentation of train-of-four ratio ≥0.90) is the only method of assuring that satisfactory recovery of neuromuscular function has taken place. The panel also recommends that subjective evaluation of the responses to train-of-four stimulation (when using a peripheral nerve stimulator) or clinical tests of recovery from NMB (such as the 5-second head lift) should be abandoned in favor of objective monitoring. During an interim period for establishing these recommendations, if only a peripheral nerve stimulator is available, its use should be mandatory in any patient receiving a neuromuscular blocking drug. The panel acknowledges that publishing this statement per se will not result in its spontaneous acceptance, adherence to its recommendations, or change in routine practice. Implementation of objective monitoring will likely require professional societies and anesthesia department leadership to champion its use to change anesthesia practitioner behavior.

Reversal of residual neuromuscular block: complications associated with perioperative management of muscle relaxation

The use of anticholinesterases to reverse residual neuromuscular block at the end of surgery became routine practice in the 1950s. These drugs could only be used when recovery from block was established [two twitches of the train-of-four (TOF) count detectable] and concern was expressed about their cholinergic side-effects. By the 1990s, it was recognized that failure to reverse residual block adequately to a TOF ratio (TOFR) >0.7 was associated with increased risk of postoperative pulmonary complications (POPCs) following the long-acting non-depolarizing neuromuscular blocking drug (NDNMBD) pancuronium. By 2003, and the introduction of acceleromyography, a TOFR ≥0.9 was considered necessary to protect the airway from aspiration before tracheal extubation. It was also considered that four, not two, twitches of the TOF should be detectable before neostigmine was given. Use of any NDNMBD was subsequently shown to be associated with increased risk of POPCs, but it was thought that neostigmine reduced that risk. Recently, there has been conflicting evidence that use of neostigmine might increase the incidence of POPCs. Although sugammadex has been shown to rapidly reverse profound neuromuscular block from aminosteroidal agents, there is currently no evidence that sugammadex is superior to neostigmine in its effect on POPCs. Other new antagonists, including cysteine to degrade CW002 and calabadion 1 and 2 to antagonize aminosteroidal and benzylisoquinolium NDNMBDs, are being studied in preclinical and clinical trials. Quantitative neuromuscular monitoring is essential whenever a NDNMBD is used to ensure full recovery from neuromuscular block.

Quantitative Relationships between Pulmonary Function and Residual Neuromuscular Blockade

Background

Neuromuscular blockade is a risk factor for postoperative respiratory weakness during the immediate postoperative period. The quantitative relationships between postoperative pulmonary-function impairment and residual neuromuscular blockade are unknown.

Methods

113 patients who underwent elective laparoscopic cholecystectomy were enrolled in this study. They all had a pulmonary-function test (PFT) during the preoperative evaluation. Predictive values based on demographic data were also recorded. The train-of-four ratio (TOFR) was recorded at the same time as the PFT and at every 5 minutes in the qualified 98 patients in the postanesthesia care unit (PACU). We analyzed the degree of PFT recovery when the TOFR had recovered to different degrees.

Results

There was a significant difference (P < 0.05) between the preoperative baseline value and the postoperative forced vital capacity at each TOFR point, except at a TOFR value of 1.1. There was also a significant difference (P < 0.05) between the preoperative baseline value and the postoperative peak expiratory flow at each TOFR point.

Conclusions

Postoperative residual neuromuscular blockade was common (75.51%) after tracheal extubation, and pulmonary function could not recover to an acceptable level (85% of baseline value), even if TOFR had recovered to 0.90.

Trial Registration

Chinese Clinical Trial Register is ChiCTR-OOC-15005838.

Neuromuscular blockers and reversal agents and their impact on anesthesia practice

Neuromuscular blockers have long been an intricate part of the anesthesia regimen. The scientific progress in pharmacology and physiology has strengthened their clinical relevance, has helped to delineate with precision their medical role, and has enhanced the safety and effectiveness of their use. New frontiers in research will define further the role of these agents in modern anesthesia practice and guide their expanding and discrete clinical applications.