A survey of the management of neuromuscular blockade monitoring in Australia and New Zealand

Machine learning based analysis and detection of trend outliers for electromyographic neuromuscular monitoring

PURPOSE

Neuromuscular monitoring is frequently plagued by artefacts, which along with the frequent unawareness of the principles of this subtype of monitoring by many clinicians, tends to lead to a cynical attitute by clinicians towards these monitors. As such, the present study aims to derive a feature set and evaluate its discriminative performance for the purpose of Train-of-Four Ratio (TOF-R) outlier analysis during continuous intraoperative EMG-based neuromuscular monitoring.

METHODS

Patient data was sourced from two devices: (1) Datex-Ohmeda Electromyography (EMG) E-NMT: a dataset derived from a prospective observational trial including 136 patients (21,891 TOF-R observations), further subdivided in two based on the type of features included; and (2) TetraGraph: a clinical case repository dataset of 388 patients (97,838 TOF-R observations). The two datasets were combined to create a synthetic set, which included shared features across the two. This process led to the training of four distinct models.

RESULTS

The models showed an adequate bias/variance balance, suggesting no overfitting or underfitting. Models 1 and 2 consistently outperformed the others, with the former achieving an F1 score of 0.41 (0.31, 0.50) and an average precision score (95% CI) of 0.48 (0.35, 0.60). A random forest model analysis indicated that engineered TOF-R features were proportionally more influential in model performance than basic features.

CONCLUSIONS

Engineered TOF-R trend features and the resulting Cost-Sensitive Logistic Regression (CSLR) models provide useful insights and serve as a potential first step towards the automated removal of outliers for neuromuscular monitoring devices.

TRIAL REGISTRATION

NCT04518761 (clinicaltrials.gov), registered on 19 August 2020.

Practice Guidelines for Monitoring Neuromuscular Blockade-Elements to Change to Increase the Quality of Anesthesiological Procedures and How to Improve the Acceleromyographic Method

Neuromuscular blocking agents are a crucial pharmacological element of general anesthesia. Decades of observations and scientific studies have resulted in the identification of many risks associated with the uncontrolled use of neuromuscular blocking agents during general anesthesia or an incomplete reversal of neuromuscular blockade in the postoperative period. Residual relaxation and acute postoperative respiratory depression are the most serious consequences. Cyclic recommendations have been developed by anesthesiology societies from many European countries as well as from the United States and New Zealand. The newest recommendations from the American Society of Anesthesiologists and the European Society of Anesthesiology were published in 2023. These publications contain very detailed recommendations for monitoring the dosage of skeletal muscle relaxants in the different stages of anesthesia-induction, maintenance and recovery, and the postoperative period. Additionally, there are recommendations for various special situations (for example, rapid sequence induction) and patient populations (for example, those with organ failure, obesity, etc.). The guidelines also refer to pharmacological drugs for reversing the neuromuscular transmission blockade. Despite the development of several editions of recommendations for monitoring neuromuscular blockade, observational and survey data indicate that their practical implementation is very limited. The aim of this review was to present the professional, technical, and technological factors that limit the implementation of these recommendations in order to improve the implementation of the guidelines and increase the quality of anesthesiological procedures and perioperative safety.

An educational intervention to reduce the incidence of postoperative residual curarisation: a cluster randomised crossover trial in patients undergoing general anaesthesia

BACKGROUND

The incidence of postoperative residual curarisation remains unacceptably high. We assessed whether an educational intervention on perioperative neuromuscular block management can reduce it.

METHODS

In this multicentre, cluster randomised crossover trial, centres were allocated to receive an educational intervention either in a first or a second period. The educational intervention consisted of a lecture about neuromuscular management key points, including quantitative neuromuscular monitoring and use of reversal agents. The lecture was streamed to allow repetition. Additionally, memory cards were distributed in each operating theatre. The primary outcome was postoperative residual curarisation in the PACU. Secondary outcomes were frequency of quantitative neuromuscular monitoring, use of reversal agents, and incidence of postoperative pulmonary complications during hospital stay. Measurements were performed before randomisation and after the first and the second period. The effect of the educational intervention was estimated using multivariable mixed effects logistic regression models.

RESULTS

We included 2314 subjects in 34 Spanish centres. Postoperative residual curarisation incidence was not affected by the educational intervention (odds ratio [OR] 0.90 [95% confidence interval {CI}: 0.51-1.58]; P=0.717 and 1.30 [0.73-2.30]; P=0.371] for first and second time-period interaction). The educational intervention increased the quantitative neuromuscular monitor usage (OR 2.04 [95% CI: 1.31-3.19]; P=0.002), the use of reversal agents was unchanged (OR 0.79 [95% CI: 0.50-1.26]; P=0.322), and the incidence of postoperative pulmonary complications decreased (OR 0.19 [95% CI: 0.10-0.35]; P<0.001).

CONCLUSIONS

An educational intervention on perioperative neuromuscular block management did not reduce the incidence of postoperative residual curarisation nor increase reversal, despite increased quantitative neuromuscular monitoring. Sugammadex reversal was associated with reduced postoperative residual curarisation. The educational intervention was associated with a decrease in postoperative pulmonary complications.

CLINICAL TRIAL REGISTRATION

NCT03128151.

Evaluation of a Protocol for the Management of Maintenance and Reversal of Rocuronium Block Using Neostigmine or Sugammadex

BACKGROUND

Postoperative residual neuromuscular blockade (PRNB) is defined as an adductor pollicis train-of-four ratio (TOFR) <0.9. It is a common postoperative complication when nondepolarizing muscle relaxants are either not reversed or reversed with neostigmine. PRNB has been reported in 25% to 58% of patients who receive intermediate-acting nondepolarizing muscle relaxants, and it is associated with increased morbidity and decreased patient satisfaction. We conducted a prospective descriptive cohort study during the implementation of a practice guideline that included the selective use of sugammadex or neostigmine. The primary study aim of this pragmatic study was to estimate the incidence of PRNB at arrival to the postanesthesia care unit (PACU) when the practice guideline is followed.

METHODS

We enrolled patients undergoing orthopedic or abdominal surgery requiring neuromuscular blockade. Rocuronium administration was guided by surgical requirements and based on ideal body weight, with dose reductions for women and/or age >55 years. Only qualitative monitoring was available to the anesthesia providers, and selection of sugammadex or neostigmine was guided by tactile assessments of the response to train-of-four (TOF) stimulation by a peripheral nerve stimulator. Neostigmine was administered if no fade was detected in the TOF response at the thumb. Deeper blocks were reversed with sugammadex. The prespecified primary and secondary end points were the incidence of PRNB at arrival to the PACU, defined as a normalized TOFR (nTOFR) < 0.9, and severe PRNB, defined as nTOFR <0.7 on arrival to the PACU. Anesthesia providers were blinded to all quantitative measurements made by research staff.

RESULTS

Analysis included 163 patients, and 145 underwent orthopedic and 18 abdominal surgeries. Of the 163 patients, 92 (56%) were reversed with neostigmine and 71 (44%) with sugammadex. The overall incidence of PRNB at PACU arrival was 5 of 163 or 3% (95% confidence interval [CI], 1-7). The incidence of severe PRNB in PACU was 1% (95% CI, 0-4). Three of the 5 subjects with PRNB had TOFR <0.4 at time of reversal but were given neostigmine since anesthesia providers detected no fade by qualitative assessment.

CONCLUSIONS

The use of a protocol that specifies rocuronium dosing and selective use of sugammadex versus neostigmine based on qualitative assessment of TOF count and fade allowed us to achieve an incidence of PRNB of 3% (95% CI, 1-7) at PACU arrival. Quantitative monitoring may be needed to further reduce this incidence.

Emergency use of sugammadex after failure of standard reversal drugs and postoperative pulmonary complications: A retrospective cohort study

Background and Aims

The use of sugammadex instead of neostigmine for the reversal of neuromuscular blockade may decrease postoperative pulmonary complications. It is unclear if this finding is applicable to situations where sugammadex is administered after the administration of neostigmine. The objective of this study was to compare the incidence of a composite outcome measure of major postoperative pulmonary complications in patients who received sugammadex as a rescue agent after neostigmine versus those who received sugammadex alone for reversal of neuromuscular blockade.

Material and Methods

This retrospective cohort study analyzed the medical records of adult patients who underwent elective inpatient noncardiac surgery under general anesthesia and received sugammadex for reversal of neuromuscular blockade, at a tertiary care academic hospital between August 2016 and November 2018.

Results

A total of 1,672 patients were included, of whom 1,452 underwent reversal with sugammadex alone and 220 received sugammadex following reversal with neostigmine/glycopyrrolate. The composite primary outcome was diagnosed in 60 (3.6%) patients. Comparing these two groups, and after adjusting for confounding factors, patients who received sugammadex after reversal with neostigmine had more postoperative pulmonary complications than those reversed with sugammadex alone (6.8% vs. 3.1%, odds ratio, 2.29; 95% confidence interval [CI], 1.25 to 4.18; P = 0.006).

Conclusion

The use of sugammadex following reversal with neostigmine was associated with a higher incidence of postoperative pulmonary complications as compared to the use of sugammadex alone. The implications of using sugammadex after the failure of standard reversal drugs should be investigated in prospective studies.

Routine administration of neostigmine after recovery of spontaneous breathing versus neuromuscular monitor-guided administration of neostigmine in pediatric patients: a parallel, randomized, controlled study

BACKGROUND

Neostigmine used to reverse the muscle relaxants should be guided by neuromuscular monitoring, as the degree of spontaneous pre-reversal recovery is the key to success to reverse the neuromuscular block. But neuromuscular monitoring is not always available for some patients during anesthesia and, in consequence, we need to use other clinical judgment to guide the use of neostigmine to reverse the neuromuscular block. In this trial, we aimed to evaluate the incidence of residual neuromuscular blockade (rNMB) in pediatric patients with routine use of neostigmine after recovery of spontaneous breathing compared with the patients with the use of neostigmine guided by neuromuscular monitoring.

METHODS

A parallel, randomized, controlled noninferiority study was conducted. We enrolled aged 3 months to 12 years old patients who underwent inguinal hernia repair under general anesthesia. The enrolled patients were randomly divided into experimental and control groups. After surgery, children in the experimental group were given 0.02 mg/kg neostigmine after recovery of spontaneous breathing. Children in the control group were given 0.02 mg/kg neostigmine when the train-of-four (TOF) ratio was between 0.4 and 0.9. However, no neostigmine was administered if the TOF ratio was higher than 0.9. The primary outcome was the incidence of rNMB after extubation (TOF ratio < 0.9). Secondary outcomes included the incidence of neostigmine-induced muscle paralysis, end of surgery - extubation interval, end of surgery - exit OR interval, the length of stay in the PACU, the incidence of hypoxia in the PACU, the number of children who required assisted ventilation during the PACU stay, and neostigmine-related adverse events.

RESULTS

A total of 120 children were included in this study, with 60 in the experimental group and 60 in the control group. There was no significant difference in the incidence of rNMB after extubation between the groups (45/60 vs 44/60, RR 1.02 [95% CI, 0.83 to 1.26], p = 0.84). There was no neostigmine-induced muscle paralysis in either group. Adverse events were similar occurred in both groups. However, time from end of the surgery to leaving the operating room was earlier in the experimental group than in the control group (13.6 ± 5.2 vs 15.7 ± 5.6 min, MD -2.10 min [95% CI, -3.70 to -0.50], p = 0.04). The risk ratio of the incidence of TOF ratio < 0.3 for the experimental group was 31.12 (95%CI, 1.89 to 512.61) compared with the control group (12/60 vs 0/60, p = 0.00) in exploratory analysis.

CONCLUSIONS

Recovery of spontaneous breathing could be used as a substitute of neuromuscular monitoring to guide neostigmine use in pediatric patients following minor surgeries. However, care should be taken for the residual neuromuscular block.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR-IOR-17012890. Registered on 5 October 2017.

Comparison of the effects of neostigmine and sugammadex on postoperative residual curarization and postoperative pulmonary complications by means of diaphragm and lung ultrasonography: a study protocol for prospective double-blind randomized controlled trial

Background

Postoperative residual curarization (PORC) may be a potential risk factor of postoperative pulmonary complications (PPCs), and both of them will lead to adverse consequences on surgical patient recovery. The train-of-four ratio (TOFr) which is detected by acceleromyography of the adductor pollicis is thought as the gold standard for the measurement of PORC. However, diaphragm function recovery may differ from that of the peripheral muscles. Recent studies suggested that diaphragm ultrasonography may be useful to reveal the diaphragm function recovery, and similarly, lung ultrasound was reported for the assessment of PPCs in recent years as well. Sugammadex reversal of neuromuscular blockade is rapid and complete, and there appear to be fewer postoperative complications than with neostigmine. This study aims to compare the effects of neostigmine and sugammadex, on PORC and PPCs employing diaphragm and lung ultrasonography, respectively.

Methods/design

In this prospective, double-blind, randomized controlled trial, patients of the American Society of Anesthesiologists Physical Status I–III, aged over 60, will be enrolled. They will be scheduled to undergo arthroplasty under general anesthesia. All patients will be allocated randomly into two groups, group NEO (neostigmine) and group SUG (sugammadex), using these two drugs for reversing rocuronium. The primary outcome of the study is the incidence of PPCs in the NEO and SUG groups. The secondary outcomes are the evaluation of diaphragm ultrasonography and lung ultrasound, performed by an independent sonographer before anesthesia, and at 10 min and 30 min after extubation in the post-anesthesia care unit, respectively.

Discussion

Elimination of PORC is a priority at the emergence of anesthesia, and it may be associated with reducing postoperative complications like PPCs. Sugammadex was reported to be superior to reverse neuromuscular blockade than neostigmine. Theoretically, complete recovery of neuromuscular function should be indicated by TOFr > 0.9. However, the diaphragm function recovery may not be the same matter, which probably harms pulmonary function. The hypothesis will be proposed that sugammadex is more beneficial than neostigmine to reduce the incidence of PPCs and strongly favorable for the recovery of diaphragm function in our study setting.

Trial registration

ClinicalTrials.gov NCT05040490. Registered on 3 September 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06328-3.

Unanticipated Profound Paralysis and Sugammadex Dosing Implications After Videoscopic Thoracic Surgery

A bedridden patient with empyema presented for thoracoscopic decortication. During the procedure, despite a post-tetanic count (PTC) of 0 via calibrated quantitative neuromuscular monitoring, persistent diaphragmatic movement impaired operating conditions, so rocuronium was re-dosed. After surgery, the patient had 0 PTC. Sugammadex was titrated to achieve baseline neuromuscular strength, monitoring the effect of each 200-mg dose. Ultimately, 1200 mg was required to achieve baseline strength. We describe monitor troubleshooting, considerations with unexpectedly deep neuromuscular blockade, the importance of routine quantitative neuromuscular monitoring, and one strategy for sugammadex reversal in patients with profound paralysis outside of the standard dosing guidelines.

Quantitative Neuromuscular Monitoring and Postoperative Outcomes: A Narrative Review

Over the past five decades, quantitative neuromuscular monitoring devices have been used to examine the incidence of postoperative residual neuromuscular block in international clinical practices, and to determine their role in reducing the risk of residual neuromuscular block and associated adverse clinical outcomes. Several clinical trials and a recent meta-analysis have documented that the intraoperative application of quantitative monitoring significantly reduces the risk of residual neuromuscular blockade in the operating room and postanesthesia care unit. In addition, emerging data show that quantitative monitoring minimizes the risk of adverse clinical events, such as unplanned postoperative reintubations, hypoxemia, and postoperative episodes of airway obstruction associated with incomplete neuromuscular recovery, and may improve postoperative respiratory outcomes. Several international anesthesia societies have recommended that quantitative monitoring be performed whenever a neuromuscular blocking agent is administered. Therefore, a comprehensive review of the literature was performed to determine the potential benefits of quantitative monitoring in the perioperative setting.

A survey of current management of neuromuscular block and reversal in Australia and New Zealand

In recent years there has been a significant investment in education on the management of neuromuscular blockade and increased availability of sugammadex in anaesthetic practice. This survey aimed to examine contemporary practice of Australian and New Zealand anaesthetists in managing neuromuscular blockade and its reversal. A web-based, voluntary survey was distributed to a cohort of 1000 Fellows of the Australian and New Zealand College of Anaesthetists. We received 229 completed responses (survey response rate of 23%). Seventy-one percent (95% confidence interval (CI) 64% to 76%) of the survey respondents thought that 5% or fewer of the patients in their hospital display clinically significant postoperative paralysis. Only 35% (95% CI 18% to 29%) thought that quantitative neuromuscular twitch monitors should be used to monitor neuromuscular block, and the dose and time given for reversal agents was often inconsistent with published recommendations. Sugammadex was the preferred reversal agent for 78% (95% CI 72% to 83%) of survey respondents, but they indicated that cost remains a significant barrier to its widespread uptake. Despite the low response rate, this survey identified that some reported practices in Australia and New Zealand deviate from guidelines and current recommendations in the management of neuromuscular blockade. If the respondents are representative of the broader anaesthetic community, there appears be a greater preference for sugammadex over neostigmine for reversal of neuromuscular blockade.

Ipsilateral and Simultaneous Comparison of Responses from Acceleromyography- and Electromyography-based Neuromuscular Monitors

BACKGROUND

The paucity of easy-to-use, reliable objective neuromuscular monitors is an obstacle to universal adoption of routine neuromuscular monitoring. Electromyography (EMG) has been proposed as the optimal neuromuscular monitoring technology since it addresses several acceleromyography limitations. This clinical study compared simultaneous neuromuscular responses recorded from induction of neuromuscular block until recovery using the acceleromyography-based TOF-Watch SX and EMG-based TetraGraph.

METHODS

Fifty consenting patients participated. The acceleromyography and EMG devices analyzed simultaneous contractions (acceleromyography) and muscle action potentials (EMG) from the adductor pollicis muscle by synchronization via fiber optic cable link. Bland-Altman analysis described the agreement between devices during distinct phases of neuromuscular block. The primary endpoint was agreement of acceleromyography- and EMG-derived normalized train-of-four ratios greater than or equal to 80%. Secondary endpoints were agreement in the recovery train-of-four ratio range less than 80% and agreement of baseline train-of-four ratios between the devices.

RESULTS

Acceleromyography showed normalized train-of-four ratio greater than or equal to 80% earlier than EMG. When acceleromyography showed train-of-four ratio greater than or equal to 80% (n = 2,929), the bias was 1.3 toward acceleromyography (limits of agreement, -14.0 to 16.6). When EMG showed train-of-four ratio greater than or equal to 80% (n = 2,284), the bias was -0.5 toward EMG (-14.7 to 13.6). In the acceleromyography range train-of-four ratio less than 80% (n = 2,802), the bias was 2.1 (-16.1 to 20.2), and in the EMG range train-of-four ratio less than 80% (n = 3,447), it was 2.6 (-14.4 to 19.6). Baseline train-of-four ratios were higher and more variable with acceleromyography than with EMG.

CONCLUSIONS

Bias was lower than in previous studies. Limits of agreement were wider than expected because acceleromyography readings varied more than EMG both at baseline and during recovery. The EMG-based monitor had higher precision and greater repeatability than acceleromyography. This difference between monitors was even greater when EMG data were compared to raw (nonnormalized) acceleromyography measurements. The EMG monitor is a better indicator of adequate recovery from neuromuscular block and readiness for safe tracheal extubation than the acceleromyography monitor.

EDITOR’S PERSPECTIVE

Postoperative residual neuromuscular blockade after reversal based on a qualitative peripheral nerve stimulator response: A randomised controlled trial

BACKGROUND

Incomplete recovery of neuromuscular blockade is a common postoperative adverse event in the postanaesthesia care unit.

OBJECTIVE

We examined and compared the incidence of residual neuromuscular blockade when the recommended dose of neostigmine or sugammadex was administered according to a qualitative nerve stimulator response.

DESIGN

A randomised controlled trial.

SETTING

A tertiary care hospital in South Korea from September 2017 to November 2017.

PATIENTS

Eighty patients aged between 18 and 69 years were included in this study. All were patients scheduled to undergo elective laparoscopic cholecystectomy and who had an American Society of Anaesthesiologists physical status of one or two were eligible.

INTERVENTIONS

Patients were allocated randomly to receive neostigmine or sugammadex at the end of surgery. The doses of the reversal agents were based on the response to peripheral nerve stimulation, which was discontinued after administration of the reversal agent.

MAIN OUTCOME MEASURES

The primary outcome was the incidence of postoperative residual neuromuscular blockade. The secondary outcomes were the incidences of symptoms or signs of residual neuromuscular blockade such as hypoxaemia, inability to maintain head-lift for 5 s and diplopia.

RESULTS

The incidence of residual neuromuscular blockade on arrival in the recovery room was 44.4% in the neostigmine group and 0% in the sugammadex group (P < 0.0001, relative risk = 1.80, 95% confidence interval 1.36 to 2.41). The incidences of adverse events in the recovery room were low and comparable between the groups.

CONCLUSION

The incidence of residual neuromuscular blockade on arrival in the recovery room was significantly higher in the neostigmine group than that in the sugammadex group. However, the incidence of adverse events was similar in the neostigmine and sugammadex groups.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03292965.

REsidual Neuromuscular Block Prediction Score Versus Train-of-Four Ratio and Respiratory Outcomes: A Retrospective Cohort Study

BACKGROUND

Residual neuromuscular blockade is associated with an increased incidence of postoperative respiratory complications. The REsidual neuromuscular block Prediction Score (REPS) identifies patients at high risk for residual neuromuscular blockade after surgery.

METHODS

A total of 101,510 adults undergoing noncardiac surgery under general anesthesia from October 2005 to December 2018 at a tertiary care center in Massachusetts were analyzed for the primary outcome of postoperative respiratory complications (invasive mechanical ventilation requirement within 7 postoperative days or immediate postextubation desaturation [oxygen saturation {Spo2} <90%] within 10 minutes). The primary objective was to assess the association between the REPS and respiratory complications. The secondary objective was to compare REPS and train-of-four (TOF) ratio <0.90 on the strength of their association with respiratory complications.

RESULTS

A high REPS (≥4) was associated with an increase in odds of respiratory complications (adjusted odds ratio [OR], 1.13 [95% confidence interval {CI}, 1.06-1.21]; P < .001). In 6224 cases with available TOF ratio measurements, a low TOF ratio (<0.9) was associated with respiratory complications (adjusted OR, 1.43 [95% CI, 1.11-1.85]; P = .006), whereas a high REPS was not (adjusted OR, 0.96 [95% CI, 0.74-1.23]; P = .73) (P = .018 for comparison between ORs).

CONCLUSIONS

The REPS may be implemented as a screening tool to encourage clinicians to use quantitative neuromuscular monitoring in patients at risk of residual neuromuscular blockade. A positive REPS should be followed by a quantitative assessment of the TOF ratio.

Utilization Patterns of Perioperative Neuromuscular Blockade Reversal in the United States: A Retrospective Observational Study From the Multicenter Perioperative Outcomes Group

BACKGROUND

Following the introduction of sugammadex to the US clinical practice, scarce data are available to understand its utilization patterns. This study aimed to characterize patient, procedure, and provider factors associated with sugammadex administration in US patients.

METHODS

This retrospective observational study was conducted across 24 Multicenter Perioperative Outcomes Group institutions in the United States with sugammadex on formulary at the time of the study. All American Society of Anesthesiologists (ASA) physical status I-IV adults undergoing noncardiac surgery from 2014 to 2018 receiving neuromuscular blockade (NMB) were eligible. The study established 3 periods based on the date of first documented sugammadex use at each institution: the presugammadex period, 0- to 6-month transitional period, and 6+ months postsugammadex period. The primary outcome was reversal using sugammadex during the postsugammadex period-defined as 6 months after sugammadex was first utilized at each institution. A multivariable mixed-effects logistic regression model controlling for institution was developed to assess patient, procedure, and provider factors associated with sugammadex administration.

RESULTS

A total of 934,798 cases met inclusion criteria. Following the 6-month transitional period, sugammadex was used on average in 40.0% (95% confidence interval [CI], 39.8-40.2) of cases receiving NMB. Multivariable analysis demonstrated sugammadex use to be associated with train-of-four count of 0-1 (adjusted odds ratio = 4.06; 95% CI, 33.83-4.31) or 2 (2.45; 2.29-2.62) vs 3-4 twitches before reversal; the amount of NMB administered (3.01; 2.88-3.16) for the highest effective dose 95 quartile compared to the lowest quartile; advanced age (1.83; 1.71-1.95) compared to age <41; male sex (1.36; 1.32-1.39) compared to female sex; major thoracic surgery (1.26; 1.13-1.39); congestive heart failure (1.17, 1.07-1.28); and ASA III or IV (1.13; 1.10-1.16) versus ASA I or II.

CONCLUSIONS

Our data demonstrate broad early clinical adoption of sugammadex following Food and Drug Administration approval. Sugammadex is used preferentially in cases with higher degrees of NMB before reversal and in patients with greater burden of comorbidities and known risk factors for residual blockade or pulmonary complications.

Non-linear regression analysis for estimating the intraoperative motor evoked potential recovery time after bolus neuromuscular blockade

The recovery time of the motor evoked potential (MEP) amplitude following a neuromuscular blockade (NMB) during surgery is useful for interpreting low-amplitude waveforms or selecting the baseline waveform. In this study, the MEP data of 195 orthopedic cases who received a bolus dose of rocuronium at the beginning of surgery, between June 2009 and January 2016 were used. A non-linear regression analysis was applied to MEP amplitude data of multiple patients. The time taken for 90% of the maximum-amplitude recovery was estimated from the identified time series model. The 90% amplitude recovery time was 88.6 min in the pharmacological model and 89.4 min in the logistic model. These results were included in the 95% confidence interval of the previous studies. Although MEP amplitude is relatively unstable because of anesthesia, the averaged time series model of MEP amplitude can be estimated by using a large number of data.

Barriers and aids to routine neuromuscular monitoring and consistent reversal practice-A qualitative study

Background

Neuromuscular monitoring is recommended whenever a neuromuscular blocking agent is administered, but surveys have demonstrated inconsistent monitoring practices. Using qualitative methods, we aimed to explore barriers and aids to routine neuromuscular monitoring and consistent reversal practice.

Methods

Focus group interviews were conducted to obtain insights into the thoughts and attitudes of individual anaesthetists, as well as the influence of colleagues and department culture. Interviews were conducted at five Danish and one US hospital. Data were analysed using template analysis.

Results

Danish anaesthetists used objective neuromuscular monitoring when administering a non‐depolarizing relaxant, but had challenges with calibrating the monitor and sometimes interpreting measurements. Residents from the US institution used subjective neuromuscular monitoring, objective neuromuscular monitoring was generally not available and most had not used it. Danish anaesthetists used neuromuscular monitoring to assess readiness for extubation, whereas US residents used subjective neuromuscular monitoring, clinical tests like 5‐second head lift and ventilatory parameters. The residents described a lack of consensus between senior anaesthesiologists in reversal practice and monitoring use. Barriers to consistent and correct neuromuscular monitoring identified included unreliable equipment, time pressure, need for training, misconceptions about pharmacokinetics of neuromuscular blocking agents and residual block, lack of standards and guidelines and departmental culture.

Conclusion

Using qualitative methods, we found that though Danish anaesthetists generally apply objective neuromuscular monitoring routinely and residents at the US institution often apply subjective neuromuscular monitoring, barriers to consistent and correct use still exist.

Quality and Impact of Survey Research Among Anesthesiologists: A Systematic Review

New technology has facilitated survey research of anesthesia professional society members. We evaluated prevailing metrics of quality and impact of published research studies based on surveys of anesthesiologists. We hypothesized that adherence to recommended practices (such as use of reminders) would be associated with increased survey response rates, and that higher response rates would be associated with higher article impact. Using the MEDLINE database, we identified 45 English-language research articles published in 2010-2017 reporting original data from surveys of anesthesiologists. The median response rate was 37% (IQR: 25-46%). Recommended survey practices, including the use of reminders (p = 0.861) and validated questionnaires (p = 0.719), were not correlated with response rates. In turn, survey response rates were not associated with measures of article impact (p = 0.528). The impact of published research based on surveys of anesthesiologists, as measured by citation scores (p = 0.493) and Altmetrics (p = 0.826), may be driven primarily by the novel data or questions raised using survey methodology, but does not appear to be associated with response rates. Improving reporting of survey methodology and understanding possible sources of non-response bias are important for future studies in this area.

Application of Neuromuscular Monitoring in Pediatric Anesthesia: A Survey in China

PURPOSE

To determine the popularity of neuromuscular monitoring in pediatric anesthesia.

DESIGN

Self-filled electronic questionnaire survey.

METHODS

Anesthesiologists were notified through a professional network platform of anesthesiology by mobile phone. The survey deadline was December 23, 2019.

FINDINGS

A total of 883 valid questionnaires were collected. A total of 738 (83%) anesthesiologists stated that they had never used neuromuscular monitoring in pediatric anesthesia, and 638 (72%) anesthesiologists stated that they were not equipped with neuromuscular monitors. A total of 869 (98.75%) anesthesiologists had used neostigmine, but only 291 (33%) anesthesiologists reported routine postoperative administration for the reversal of neuromuscular block.

CONCLUSIONS

Neuromuscular monitoring in pediatric anesthesia needs to be further popularized. However, how to effectively and safely use neuromuscular antagonists are also important issues that require attention from anesthesiologists.

Assessment of the effects of sugammadex on coagulation profiles using thromboelastographic parameters

This study evaluated the effects of sugammadex at conventional doses of 2 and 4 mg/kg on the coagulation profile by analyzing thromboelastographic parameters and performing a traditional laboratory coagulation analysis. A total of 100 patients undergoing arthroscopic shoulder surgery were enrolled. The patients were randomly divided into the 2 mg and 4 mg groups. The laboratory coagulation test and thromboelastographic analysis were performed before and 15 min after administering sugammadex. Prothrombin time (PT) was significantly prolonged after sugammadex administration than before it in intragroup comparisons of the 2 mg group (12.8 ± 0.6 s vs. 13.6 ± 0.7 s, p < 0.001) and the 4 mg group (13.0 ± 0.5 s vs. 13.7 ± 0.5 s, p < 0.001). R time, derived from thromboelastography, was also significantly prolonged after sugammadex administration (4.7 ± 1.8 min vs. 5.8 ± 2.1 min, p = 0.005). In conclusion, the conventional doses of 2 or 4 mg/kg sugammadex prolonged PT. Sugammadex 4 mg/kg also prolonged R time, although the value was within the normal range. Therefore, physicians should be cautious with the higher sugammadex dose, particularly in patients with a high risk of bleeding because the higher dose was associated with less coagulation.

Trial registration: KCT0002133 (https://cris.nih.go.kr).

A retrospective observational study of neuromuscular monitoring practice in 30,430 cases from six Danish hospitals

Timely application of objective neuromuscular monitoring can avoid residual neuromuscular blockade. We assessed the frequency of objective neuromuscular monitoring with acceleromyography and the last recorded train‐of‐four ratio in a cohort of Danish patients. We extracted data from all patients receiving general anaesthesia from November 2014 to November 2016 at six hospitals in the Zealand Region of Denmark. Acceleromyography was available in all operating rooms and data were recorded automatically. The primary outcome measure was acceleromyography use in patients receiving neuromuscular blocking agents, divided into non‐depolarising agents and succinylcholine only. The dataset included 76,743 cases, of which 30,430 received a neuromuscular blocking drug. Non‐depolarising drugs were used in 16,525 (54%) and succinylcholine as the sole drug in 13,905 (46%) cases. Acceleromyography was used in 14,463 (88%) patients who received a non‐depolarising neuromuscular blocking drug and in 4224 (30%) receiving succinylcholine alone. Acceleromyography use varied between the departments from 58% to 99% for non‐depolarising drugs and from 3% to 79% for succinylcholine alone. The median (IQR [range]) of the last recorded train‐of‐four ratio before tracheal extubation was 0.97 (0.90–1.06 [0.01–2.20]) when non‐depolarising drugs were used, and was less than 0.9 in 22% of cases. The OR for oxygen desaturation was higher with the use of succinylcholine [2.51 (95%CI 2.33–2.70) p < 0.001] and non‐depolarising drugs [2.57 (95%CI 2.32–2.84) p < 0.001] as compared with cases where no neuromuscular blockade drug was used. In conclusion, acceleromyography was almost always used in cases where non‐depolarising neuromuscular blocking drugs were used, but a train‐of‐four ratio of 0.9 was not always achieved. Monitoring was used in less than 30% of cases where succinylcholine was the sole drug used.

Awake Volunteer Pain Scores During Neuromuscular Monitoring

BACKGROUND

There is a need for easy to use, reliable neuromuscular monitors (NMMs). This multicenter, prospective, unblinded study compared the discomfort associated with neurostimulation in unmedicated healthy volunteers when using the new electromyography (EMG)-based TetraGraph and acceleromyography (AMG)-based TOF-Watch NMMs. The secondary aim was to compare the repeatability of the train-of-four (TOF) ratios (TOFRs) obtained with the 2 devices.

METHODS

The TOF measurements of 135 volunteers from 3 university hospitals were analyzed (age: 38.3 ± 12 years [mean ± standard deviation [SD]]; male/female ratio = 63:72). The left or right ulnar nerve was stimulated at the wrist in TOF mode with 20, 30, 40, and 50 mA stimulating current intensities with both devices in random order. The TOF-Watch used standard electrocardiography (ECG) electrodes (Red Dot; 3M Health Care) for nerve stimulation. The stimulating surface area of 1 ECG electrode is 113 mm. The piezoelectric probe was attached to the thumb, and a hand adapter was used to ensure consistency of AMG measurements. The TetraGraph uses proprietary surface strip electrodes for nerve stimulation and muscle action potential recording, whose stimulating surface area is roughly twice as big as that of standard ECG electrodes (228.5 mm). The volunteers were asked to rate the discomfort associated with neurostimulation on a 0-10 verbal numerical rating scale (VNRS) score anchored with 0 (no pain) and 10 (worst pain ever experienced). A linear mixed-effects model was used to evaluate the difference in VNRS scores between devices. P <.05 was accepted as the level of significance.

RESULTS

In the linear mixed-effects model, there were no differences in VNRS scores between devices at any of the stimulating current intensities, P = .38. The median (range) VNRS scores obtained with TOF-Watch and TetraGraph devices were 2 (0-7) vs 2 (0-8) at 20 mA, 3 (1-9) vs 3 (1-9) at 30 mA, 5 (1-10) vs 5 (1-10) at 40 mA, and 5 (1-10) vs 6 (1-10) at 50 mA stimulating current intensities. The mean of the 1469 TOFRs obtained with TetraGraph was 100.43% ± 7.74% (standard error = 0.2%). Due to technical difficulties, the repeatability of the TOFRs could not be determined.

CONCLUSIONS

Despite the different size and design of the stimulating electrodes, the 2 NMMs caused the same level of discomfort in unmedicated healthy volunteers.

Clinical Practice Guideline for the Management of Neuromuscular Blockade: What Are the Recommendations in the USA and Other Countries?

Purpose of Review

This review addresses various societal guidelines, standards, and consensus statements regarding optimal neuromuscular blockade management. We discuss the historical evolution of neuromuscular management as a means of identifying possible future trends.

Recent Findings

While a recent international panel of experts has called for abandoning clinical assessment and subjective evaluation using a peripheral nerve stimulator in favor of adopting quantitative monitoring, few anesthesia societies mandate similar practices at the moment.

Summary

The current status of neuromuscular monitoring in the world is still variable and unsatisfactory. Nevertheless, a positive trend can be observed in the anesthesia community to adopt and learn this neglected technique. The development of user-friendly monitoring devices should also help this process, but anesthesia national societies still need to do a lot to replace outdated and substandard practices.

Association of neuromuscular reversal by sugammadex and neostigmine with 90-day mortality after non-cardiac surgery

Background

Reversing a neuromuscular blockade agent with sugammadex is known to lessen postoperative complications by reducing postoperative residual curarization. However, its effects on 90-day mortality are unknown. Therefore, this study aimed to compare the effects of sugammadex and neostigmine in terms of 90-day mortality after non-cardiac surgery.

Methods

This retrospective cohort study analyzed the medical records of adult patients aged 18 years or older who underwent non-cardiac surgery at a single tertiary care hospital between 2011 and 2016. Propensity score matching and Cox regression analysis were used to investigate the effectiveness of sugammadex and neostigmine in lowering 90-day mortality after non-cardiac surgery.

Results

A total of 65,702 patients were included in the analysis (mean age: 52.3 years, standard deviation: 15.7), and 23,532 of these patients (35.8%) received general surgery. After propensity score matching, 14,179 patients (3906 patients from the sugammadex group and 10,273 patients from the neostigmine group) were included in the final analysis. Cox regression analysis in the propensity score-matched cohort showed that the risk of 90-day mortality was 40% lower in the sugammadex group than in the neostigmine group (hazard ratio: 0.60, 95% confidence interval: 0.37, 0.98; P = 0.042). These results were similar in the multivariable Cox regression analysis of the entire cohort (hazard ratio: 0.62, 95% confidence interval: 0.39, 0.96; P = 0.036).

Conclusions

This retrospective cohort study suggested that reversing rocuronium with sugammadex might be associated with lower 90-day mortality after non-cardiac surgery compared to neostigmine. However, since this study did not evaluate quantitative neuromuscular function in the postoperative period due to its retrospective design, the results should be interpreted carefully. Future prospective studies with quantitative neuromuscular monitoring in the postoperative period should be performed to confirm these results.

Effects of high neuromuscular blocking agent dose on post-operative respiratory complications in infants and children

BACKGROUND

This study evaluated the association between neuromuscular blocking agent dose and post-operative respiratory complications in infants and children.

METHODS

Data from 6507 general anaesthetics provided to children aged 0-10 years undergoing surgery were analysed to examine the effects of neuromuscular blocking agent dose on post-operative respiratory complications (primary endpoint) and secondary endpoints. Confounder-adjusted analyses addressed age, surgical duration, and comorbidity burden.

RESULTS

In confounder-adjusted analyses, high doses of neuromuscular blocking agents were associated with higher risk of post-operative respiratory complications (OR 2.27; 95% CI 1.12-4.59; P = .022). The effect was modified by age (P-for-interaction = .016) towards a more substantial risk in infants ≤1 year (OR 3.84; 95% CI 1.35-10.94; P = .012), by duration of surgery (P-for-interaction = .006) towards a higher difference in odds for surgeries <90 minutes (OR 4.25; 95% CI 1.19-15.18; P = .026), and by ASA physical status (P-for-interaction = .015) with a greater effect among patients with higher operative risk (ASA >1: OR 3.17; 95% CI 1.43-7.04; P = .005). Neostigmine reversal did not modify the association between neuromuscular blocking agents and post-operative respiratory complications (P-for-interaction = .38). Instrumental variable analysis confirmed that high doses of neuromuscular blocking agents were associated with post-operative respiratory complications (probit coefficient 0.25; 95% CI 0.04-0.46; P = .022), demonstrating robust results regarding concerns of unobserved confounding.

CONCLUSIONS

High dose of neuromuscular blocking agents is associated with post-operative respiratory complications. We have identified subcohorts of paediatric patients who are particularly vulnerable to the respiratory side-effects of neuromuscular blocking agents: infants, paediatric patients undergoing surgeries of short duration, and those with a high ASA risk score.

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.

A multicenter survey on the use of neuromuscular blockade in Greece. Does the real-world clinical practice indicate the necessity of guidelines?

Background and Aims

The aim of this study was to investigate the current status of clinical practice regarding neuromuscular blocking drugs and their antagonists in Greece.

Material and Methods

This is a multicenter survey, including a questionnaire based on previous studies, which was translated and modified by a Task Force of the Hellenic Society of Anaesthesiology. It was completed on a web-based database after invitation via e-mail and was left online for a period of 2 months.

Results

A total of 1,100 questionnaires were sent, with a response rate of 7.9%. 13.7% stated that they do not use neuromuscular monitoring. Rocuronium was most commonly used for intubation ["often" stated by 19 (21.8%) and "very often" by 62 (71.2%)], followed by cis-atracurium, atracurium, and succinylcholine. Neostigmine and sugammadex were both used, with reversal not always administered by 23 (26.4%). Both agents were mostly used at fixed doses and not calculated based on TOF monitoring or body weight. Sugammadex was preferred in special patient groups and in operations of short duration. Reversal was most often administered based on clinical signs of neuromuscular recovery rather than objective monitoring. A significant percentage of respondents used an inadequate TOF ratio for extubation [37 (43.2%) used a TOF ratio <90%]. The reported incidence of observed residual neuromuscular blockade (RNMB) was 44.8%.

Conclusion

Great variability was observed in Greek clinical practice regarding the use of neuromuscular blockade, which indicates serious issues that must be addressed. The needs for educating anesthesia providers and developing official guidelines are obvious in order to improve patient outcomes.

The effect of preload on electromyographic train-of-four ratio at the first dorsal interosseous muscle during spontaneous recovery from neuromuscular blockade

Accurate and reliable quantitative neuromuscular function monitoring is desirable for the optimal management of neuromuscular blockade, selection of the most appropriate reversal agent and dosage, and assessing the completeness of reversal to exclude residual neuromuscular blockade. Applying preload to the thumb may affect the precision of electromyography. This study compared the precision and agreement of electromyography with and without preload during recovery from non-depolarising neuromuscular blockade. After induction of anaesthesia and before neuromuscular blockade, the supramaximal current required at the first dorsal interosseous muscle with and without preload was determined. During recovery, train-of-four ratios were recorded using electromyography every 20 seconds. Alternating pairs of measurements (with and without preload) were obtained until spontaneous recovery was achieved. The preload device applied a resting tension of 75-150 g to the thumb. Bland-Altman analysis for repeated measurements was used to assess precision and agreement of electromyography responses with and without muscle preload. Two hundred and seventy-five sets of repeated measurements were collected from 35 participants. The repeatability coefficient for train-of-four ratios recorded by electromyography with a preload was 0.030 (95% confidence intervals, CI, 0.028 to 0.031) versus 0.068 (95% CI 0.064 to 0.072) without. Train-of-four ratios with preload demonstrated a bias of +0.038 (95% CI 0.037 to 0.042) compared to electromyography without, with 95% limits of agreement of 0.035-0.111. Preload significantly improved the precision of electromyographic train-of-four ratios, with 95% of consecutive measurements differing by less than 3%. Furthermore, electromyography with preload demonstrated a positive bias of 0.04 compared with electromyography alone, the clinical significance of which requires further research.

Comparison of the TOFscan and the TOF-Watch SX during Recovery of Neuromuscular Function

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

Quantitative neuromuscular monitoring is required to ensure neuromuscular function has recovered completely at the time of tracheal extubation. The TOFscan (Drager Technologies, Canada) is a new three-dimensional acceleromyography device that measures movement of the thumb in multiple planes. The aim of this observational investigation was to assess the agreement between nonnormalized and normalized train-of-four values obtained with the TOF-Watch SX (Organon, Ireland) and those obtained with the TOFscan during recovery from neuromuscular blockade.

Methods

Twenty-five patients were administered rocuronium, and spontaneous recovery of neuromuscular blockade was allowed to occur. The TOFscan and TOF-Watch SX devices were applied to opposite arms. A preload was applied to the TOF-Watch SX, and calibration was performed before rocuronium administration. Both devices were activated, and train-of-four values were obtained every 15 s. Modified Bland–Altman analyses were conducted to compare train-of-four ratios measured with the TOFscan to those measured with the TOF-Watch SX (when train-of-four thresholds of 0.2 to 1.0 were achieved).

Results

Bias and 95% limits of agreement between the TOF-Watch SX and the TOFscan at nonnormalized train-of-four ratios between 0.2 and 1.0 were 0.021 and −0.100 to 0.141, respectively. When train-of-four measures with the TOF-Watch SX were normalized, bias and 95% limits of agreement between the TOF-Watch SX and the TOFscan at ratios between 0.2 and 1.0 were 0.015 and −0.097 to 0.126, respectively.

Conclusions

Good agreement between the TOF-Watch SX with calibration and preload application and the uncalibrated TOFscan was observed throughout all stages of neuromuscular recovery.

Residual Neuromuscular Blockade in the Critical Care Setting

Residual neuromuscular blockade is a widespread challenge for providers in the acute care setting that, if left unrecognized or untreated, places patients at higher risk for morbidity and mortality. The condition is estimated to occur in 26% to 88% of patients undergoing general anesthesia. The role of the advanced practice nurse in the acute care setting is to facilitate a safe recovery process by identifying early signs of deterioration and supporting the patient until full muscular strength has returned. This article discusses the prevalence of residual neuromuscular blockade and associated complications and patient risk factors. A review is included of the current uses for neuromuscular blockade, pathophysiology of the neuromuscular junction, pharmacologic characteristics of neuromuscular blocking agents (including drug-drug interactions), monitoring modalities, and effectiveness of reversal agents. Treatment recommendations pertinent to residual neuromuscular blockade are outlined.

Neuromuscular monitoring: an update

This review makes an advocacy for neuromuscular blockade monitoring during anaesthesia care, by: (i) describing the fundamental principles of the methods currently available, at the same time emphasizing quantitative recording measurements; (ii) describing the different ways in which muscles respond to the effect of neuromuscular blockade and their use in clinical practice; (iii) presenting results of different studies on timing and agents of neuromuscular block reversal, including a recommendation for sugammadex use and experimental results with calabadion and (iv) in the end emphasizing the need for implementing neuromuscular monitoring as a practice that should be used every time a neuromuscular block is required.

Recovery of muscle function after deep neuromuscular block by means of diaphragm ultrasonography and adductor of pollicis acceleromyography with comparison of neostigmine vs. sugammadex as reversal drugs: study protocol for a randomized controlled trial

Background

The extensive use of neuromuscular blocking agents (NMBAs) during surgical procedures still leads to potential residual paralyzing effects in the postoperative period. Indeed, neuromuscular monitoring in an intra-operative setting is strongly advocated. Acetylcholinesterase inhibitors can reverse muscle block, but their short half-life may lead to residual curarization in the ward, especially when intermediate or long-acting NMBAs have been administered. Sugammadex is the first selective reversal drug for steroidal NMBAs; it has been shown to give full and rapid recovery of muscle strength, thus minimizing the occurrence of residual curarization. Acceleromyography of the adductor pollicis is the gold standard for detecting residual curarization, but it cannot be carried out on conscious patients. Ultrasonography of diaphragm thickness may reveal residual effects of NMBAs in conscious patients.

Methods/design

This prospective, double-blind, single-center randomized controlled study will enroll patients (of American Society of Anesthesiologists physical status I–II, aged 18–80 years) who will be scheduled to undergo deep neuromuscular block with rocuronium for ear, nose, or throat surgery. The study’s primary objective will be to compare the effects of neostigmine and sugammadex on postoperative residual curarization using two different tools: diaphragm ultrasonography and acceleromyography of the adductor pollicis. Patients will be extubated when the train-of-four ratio is > 0.9. Diaphragm ultrasonography will be used to evaluate the thickening fraction, which is the difference between the end expiratory thickness and the end inspiratory thickness, normalized to the end expiratory thickness. Ultrasonography will be performed before the initiation of general anesthesia, before extubation, and 10 and 30 min after discharging patients from the operating room. The secondary objective will be to compare the incidence of postoperative complications due to residual neuromuscular block between patients who receive neostigmine and those who receive sugammadex.

Discussion

Postoperative residual curarization is a topic of paramount importance, because its occurrence can cause complications and increase the length of stay in hospital and the related costs. Diaphragm ultrasound assessment may become a bedside integrative tool in the neuromuscular monitoring field to detect concealed residual curarization in surgical patients who have received paralyzing agents.

Trial registration

EudraCT, 2013-004787-62. Registered on 18 June 2014, as “Evaluation of muscle function recovery after deep neuromuscular blockade by acceleromyography of the adductor pollicis or diaphragmatic echography: comparison between sugammadex and neostigmine.”

ClinicalTrials.gov,NCT02698969. Registered on 15 February 2016, as “Recovery of Muscle Function After Deep Neuromuscular Block by Means of Diaphragm Ultrasonography and Adductor Pollicis Acceleromyography: Comparison of Neostigmine vs. Sugammadex as Reversal Drugs.”

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2525-7) contains supplementary material, which is available to authorized users.

Objective neuromuscular monitoring of neuromuscular blockade in Denmark: an online-based survey of current practice

BACKGROUND

Neuromuscular blocking agents are commonly used during general anaesthesia but can lead to postoperative residual neuromuscular blockade and associated morbidity. With appropriate objective neuromuscular monitoring (objNMM) residual blockade can be avoided. In this survey, we investigated the use of objNMM in Denmark.

METHODS

We conducted an anonymous Internet-based survey distributed through e-mails to Danish public anaesthesia departments. The survey consisted of 15-17 short questions regarding the use of objNMM.

RESULTS

A total of 653 (27%) anaesthetists from 90% of the hospitals answered the questionnaire. ObjNMM was always used by 58% of the anaesthetists and 86% used objNMM at least 75% of the times. Despite the frequent use, 75% of the anaesthetists experienced difficulties with objNMM in at least 25% of the cases. The likelihood of using objNMM was higher among nurse anaesthetists vs. anaesthesiologists (odds ratio (OR) 2.24 [95% confidence interval (CI): 1.62-3.08]), if the department had an employee with special interest in objNMM (OR 1.66 [95% CI: 1.12-2.47]), if the anaesthetist had < 5 years of experience (OR 1.88 [95% CI: 1.29-2.73]), or if experiencing difficulties with objNMM < 25% of the cases (OR 1.60 [95% CI: 1.00-2.57]).

CONCLUSION

In this survey, Danish anaesthetists frequently, in an international perspective, use objNMM, but the use is often associated with technical difficulties.

Current Status of Neuromuscular Reversal and Monitoring

Postoperative residual neuromuscular block has been recognized as a potential problem for decades, and it remains so today. Traditional pharmacologic antagonists (anticholinesterases) are ineffective in reversing profound and deep levels of neuromuscular block; at the opposite end of the recovery curve close to full recovery, anticholinesterases may induce paradoxical muscle weakness. The new selective relaxant-binding agent sugammadex can reverse any depth of block from aminosteroid (but not benzylisoquinolinium) relaxants; however, the effective dose to be administered should be chosen based on objective monitoring of the depth of neuromuscular block.

To guide appropriate perioperative management, neuromuscular function assessment with a peripheral nerve stimulator is mandatory. Although in many settings, subjective (visual and tactile) evaluation of muscle responses is used, such evaluation has had limited success in preventing the occurrence of residual paralysis. Clinical evaluations of return of muscle strength (head lift and grip strength) or respiratory parameters (tidal volume and vital capacity) are equally insensitive at detecting neuromuscular weakness. Objective measurement (a train-of-four ratio greater than 0.90) is the only method to determine appropriate timing of tracheal extubation and ensure normal muscle function and patient safety.

A discrete event simulation model of clinical and operating room efficiency outcomes of sugammadex versus neostigmine for neuromuscular block reversal in Canada

Background

The objective of this analysis is to explore potential impact on operating room (OR) efficiency and incidence of residual neuromuscular blockade (RNMB) with use of sugammadex (Bridion™, Merck & Co., Inc., Kenilworth, NJ USA) versus neostigmine for neuromuscular block reversal in Canada.

Methods

A discrete event simulation (DES) model was developed to compare ORs using either neostigmine or sugammadex for NMB reversal over one month. Selected inputs included OR procedure and turnover times, hospital policies for paid staff overtime and procedural cancellations due to OR time over-run, and reductions in RNMB and associated complications with sugammadex use. Trials show sugammadex’s impact on OR time and RNMB varies by whether full neuromuscular recovery (train-of-four ratio ≥0.9) is verified prior to extubation in the OR. Scenarios were therefore evaluated reflecting varied assumptions for neuromuscular reversal practices.

Results

With use of moderate neuromuscular block, when full neuromuscular recovery is verified prior to extubation (93 procedures performed with sugammadex, 91 with neostigmine), use of sugammadex versus neostigmine avoided 2.4 procedural cancellations due to OR time over-run and 33.5 h of paid staff overtime, while saving an average of 62 min per OR day. No difference was observed between comparators for these endpoints in the scenario when full neuromuscular recovery was not verified prior to extubation, however, per procedure risk of RNMB at extubation was reduced from 60% to 4% (reflecting 51 cases prevented), with associated reductions in risks of hypoxemia (12 cases avoided) and upper airway obstruction (23 cases avoided).

Sugammadex impact in reversing deep neuromuscular block was evaluated in an exploratory analysis. When it was hypothetically assumed that 30 min of OR time were saved per procedure, the number of paid hours of staff over-time dropped from 84.1 to 32.0, with a 93% reduction in the per patient risk of residual blockade.

Conclusions

In clinical practice within Canada, for the majority of patients currently managed with moderate neuromuscular block, the principal impact of substituting sugammadex for neostigmine is likely to be a reduction in the risk of residual blockade and associated complications. For patients maintained at a deep level of block to the end of the procedure, sugammadex is likely to both enhance OR efficiency and reduce residual block complications.

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-016-0281-3) contains supplementary material, which is available to authorized users.

Current Trends in Neuromuscular Blockade, Management, and Monitoring amongst Singaporean Anaesthetists

Introduction. This survey aimed to investigate the attitudes/practice pertaining the use, management, and monitoring of neuromuscular blockade amongst Singaporean anaesthetists. Methods. All specialist accredited anaesthetists registered with the Singapore Medical Council were invited to complete an anonymous online survey. Results. The response rate was 39.5%. Neuromuscular monitoring (NM) was used routinely by only 13.1% despite the widespread availability of monitors. 82% stated residual NMB (RNMB) was a significant risk factor for patient outcome, but only 24% believed NMB monitoring should be compulsory in all paralyzed patients. 63.6% of anaesthetists estimated the risk of RNMB in their own institutions to be <5%. 63.1% always gave reversal. Neostigmine was predominantly used (85.1%), with 28.2% using sugammadex at least sometimes, citing unavailability and high costs. However, 83.8% believed in sugammadex's benefits for patients' safety and >50% said such benefits may be able to offset the associated costs. Conclusions. There is a significant need for reeducation about RNMB, studies on local RNMB incidences, and strengthening of current monitoring practices and guidelines. Strategies are discussed. As NM monitors appear widely available and reversal of NMB standard practice, it is hopeful that Singaporean anaesthetists will change and strive for evidence-based best clinical practice to enhance patient safety.

Sugammadex facilitates early recovery after surgery even in the absence of neuromuscular monitoring in patients undergoing laryngeal microsurgery: a single-center retrospective study

Background

In many countries, routine clinical anaesthesia does not always involve neuromuscular monitoring. In these clinical settings, the efficacy and safety of sugammadex use has not yet been confirmed. We investigated the efficacy and safety of sugammadex in the absence of neuromuscular monitoring.

Methods

One hundred and forty patients who underwent laryngeal microsurgery with the use of rocuronium as a neuromuscular blocking agent, without the use of a neuromuscular monitoring device, were retrospectively investigated. The patients were randomly chosen among all the patients who met the inclusion criteria at a tertiary university hospital between July 2013 and February 2015 and were allocated to group S (sugammadex group) or group P (pyridostigmine group) according to the neuromuscular reversal agent administered. Five patients were excluded from analysis and 135 patients completed the study. Primary outcome was extubation time. Secondary outcomes were anaesthesia time, the correlation between anaesthesia time and extubation time, the total amount of rocuronium, and postoperative adverse events in the post-anaesthesia care unit (PACU).

Results

Extubation time was significantly shorter in group S (6.3 ± 3.9 min) than in group P (9.0 ± 5.4 min). Anaesthesia time was also significantly shorter in group S (30.7 ± 10.3 min) than in group P (35.8 ± 12.6 min). In the patients with an anaesthesia time of 30 min or less, there was a positive correlation between anaesthesia time and extubation time in group P (r = 0.453), but there was no significant relationship in group S. The total amount of rocuronium used was higher in group S (0.62 ± 0.11 mg kg⁻¹) than in group P (0.38 ± 0.14 mg kg⁻¹). Postoperative adverse events in the PACU were comparable between the groups, except for tachycardia events: the incidence of tachycardia was significantly lower in group S (8.0 %) than in group P (17.3 %).

Conclusions

Sugammadex could shorten anaesthesia and extubation times as well as recovery time in the PACU and reduce postoperative hemodynamic complications in a clinical setting in the absence of neuromuscular monitoring. This may enhance the patients’ recovery in the operating room and PACU while improving the postoperative condition of patients.

Trial registration

The trial was registered in the UMIN clinical trials registry (www.umin.ac.jp/ctr/index/htm; unique trial number: UMIN000016602; registration number: R000019266; principal investigator’s name: Byung Gun Lim; date of registration: February 22, 2015).

Electronic supplementary material

The online version of this article (doi:10.1186/s12871-016-0221-2) contains supplementary material, which is available to authorized users.

Use of neuromuscular blockers in Brazil

The objective of this study was to evaluate how Brazilian anesthesiologists are using neuromuscular blockers, focusing on how they establish the diagnosis of postoperative residual curarization and the incidence of complications associated with the use of neuromuscular blockers. A questionnaire was sent to anesthesiologists inviting them to participate in the study. The online data collection remained open from March 2012 to June 2013. During the study period, 1296 responses were collected. Rocuronium, atracurium, and cisatracurium were the main neuromuscular blockers used in cases of elective surgery. Succinylcholine and rocuronium were the main neuromuscular blockers used in cases of emergency surgery. Less than 15% of anesthesiologists reported the frequent use of neuromuscular function monitors. Only 18% of those involved in the study reported that all workplaces have such a monitor. Most respondents reported using only the clinical criteria to assess whether the patient is recovered from the muscle relaxant. Most respondents also reported always using some form of neuromuscular blockade reversal. The major complications attributed to neuromuscular blockers were residual curarization and prolonged blockade. Eighteen anesthesiologists reported death attributed to neuromuscular blockers. Residual or prolonged blockade is possibly recorded as a result of the high rate of using clinical criteria to diagnose whether the patient has recovered or not from motor block and, as a corollary, the poor use of neuromuscular transmission monitors in daily practice.

Current recommendations for monitoring depth of neuromuscular blockade

PURPOSE OF REVIEW

Residual neuromuscular block is a relatively frequent occurrence and is associated with postoperative pulmonary complications, including aspiration, pneumonia and hypoxia, impaired hypoxic ventilatory drive and decreased patient satisfaction. Although adequate recovery of neuromuscular function has been defined as a train-of-four ratio of at least 0.9, monitoring with a qualitative peripheral nerve stimulator makes it impossible to determine the actual train-of-four ratio.

RECENT FINDINGS

Peripheral nerve stimulators are not routinely used in clinical practice. Without their use, dosing of neuromuscular blocking agents and anticholinesterases is often inappropriate and adequacy of recovery of neuromuscular function upon tracheal extubation cannot be guaranteed.

SUMMARY

Use of peripheral nerve stimulators allows clinicians to administer neuromuscular blocking and reversal agents in a rational manner. Routine use of quantitative monitors of depth of neuromuscular blockade is the best guarantee of the adequacy of recovery of postoperative muscle strength.

Dose-dependent Association between Intermediate-acting Neuromuscular-blocking Agents and Postoperative Respiratory Complications

Background:

Duration of action increases with repeated administration of neuromuscular-blocking agents, and intraoperative use of high doses of neuromuscular-blocking agent may affect respiratory safety.

Methods:

In a hospital-based registry study on 48,499 patients who received intermediate-acting neuromuscular-blocking agents, the authors tested the primary hypothesis that neuromuscular-blocking agents are dose dependently associated with the risk of postoperative respiratory complications. In the secondary analysis, the authors evaluated the association between neostigmine dose given for reversal of neuromuscular-blocking agents and respiratory complications. Post hoc, the authors evaluated the effects of appropriate neostigmine reversal (neostigmine ≤60 μg/kg after recovery of train-of-four count of 2) on respiratory complications. The authors controlled for patient-, anesthesia-, and surgical complexity–related risk factors.

Results:

High doses of neuromuscular-blocking agents were associated with an increased risk of postoperative respiratory complications (n = 644) compared with low doses (n = 205) (odds ratio [OR], 1.28; 95% CI, 1.04 to 1.57). Neostigmine was associated with a dose-dependent increase in the risk of postoperative respiratory complications (OR, 1.51; 95% CI, 1.25 to 1.83). Post hoc analysis revealed that appropriate neostigmine reversal eliminated the dose-dependent association between neuromuscular-blocking agents and respiratory complications (for neuromuscular-blocking agent effects with appropriate reversal: OR, 0.98; 95% CI, 0.63 to 1.52).

Conclusions:

The use of neuromuscular-blocking agents was dose dependently associated with increased risk of postoperative respiratory complications. Neostigmine reversal was also associated with a dose-dependent increase in the risk of respiratory complications. However, the exploratory data analysis suggests that the proper use of neostigmine guided by neuromuscular transmission monitoring results can help eliminate postoperative respiratory complications associated with the use of neuromuscular-blocking agents.