atropine in combination with neostigmine on cardiovascular system for reversal of residual neuromuscular blockade in the elderly: a randomized controlled trial

BACKGROUND

Glycopyrrolate-neostigmine (G/N) for reversing neuromuscular blockade (NMB) causes fewer changes in heart rate (HR) than atropine-neostigmine (A/N). This advantage may be especially beneficial for elderly patients. Therefore, this study aimed to compare the cardiovascular effects of G/N and A/N for the reversal of NMB in elderly patients.

METHODS

Elderly patients aged 65-80 years who were scheduled for elective non-cardiac surgery under general anesthesia were randomly assigned to the glycopyrrolate group (group G) or the atropine group (group A). Following the last administration of muscle relaxants for more than 30 min, group G received 4 ug/kg glycopyrrolate and 20 ug/kg neostigmine, while group A received 10 ug/kg atropine and 20 ug/kg neostigmine. HR, mean arterial pressure (MAP), and ST segment in lead II (ST-II) were measured 1 min before administration and 1-15 min after administration.

RESULTS

HR was significantly lower in group G compared to group A at 2-8 min after administration (P < 0.05). MAP was significantly lower in group G compared to group A at 1-4 min after administration (P < 0.05). ST-II was significantly depressed in group A compared to group G at 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 14, and 15 min after administration (P < 0.05).

CONCLUSIONS

In comparison to A/N, G/N for reversing residual NMB in the elderly has a more stable HR, MAP, and ST-II within 15 min after administration.

A prospective cohort study

BACKGROUND

Data concerning the depth of neuromuscular blockade (NMB) required for effective relaxation of the respiratory muscles in ARDS are scarce. We hypothesised that complete versus partial NMB can modify respiratory mechanics.

METHOD

Prospective study to compare the respiratory mechanics of ARDS patients according to the NMB depth. Each patient was analysed at two times: deep NMB (facial train of four count (TOFC) = 0) and intermediate NMB (TOFC >0). The primary endpoint was the comparison of chest wall elastance (ELCW) according to the NMB level.

RESULTS

33 ARDS patients were analysed. There was no statistical difference between the ELCW at TOFC = 0 compared to TOFC >0: 7 cmH2O/l [5.7-9.5] versus 7 cmH2O/l [5.3-10.8] (p = 0.36). The depth of NMB did not modify the expiratory nor inspiratory oesophageal pressure (Pesexp = 8 cmH2O [5-9.5] at TOFC = 0 versus 7 cmH2O [5-10] at TOFC >0; (p = 0.16) and Pesinsp = 10 cmH2O [8.2-13] at TOFC = 0 versus 10 cmH2O [8-13] at TOFC >0; (p = 0.12)).

CONCLUSION

In ARDS, the relaxation of the respiratory muscles seems to be independent of the NMB level.

Ethnic Disparities in Deep Sedation of Patients with Acute Respiratory Distress Syndrome in the United States: Secondary Analysis of a Multicenter Randomized Trial

Rationale: Patients identified as Hispanic, the largest minority group in the United States, are more likely to die from acute respiratory distress syndrome (ARDS) than non-Hispanic patients. Mechanisms to explain this disparity remain unidentified. However, Hispanic patients may be at risk of overexposure to deep sedation because of language differences between patients and clinicians, and deep sedation is associated with higher ARDS mortality.Objective: We examined associations between Hispanic ethnicity and exposure to deep sedation among patients with ARDS.Methods: A secondary analysis was conducted of patients enrolled in the control arm of a randomized trial of neuromuscular blockade for ARDS across 48 U.S. hospitals. Exposure to deep sedation was measured over the first 5 days that a patient was alive and received mechanical ventilation. Multilevel mixed-effects models were used to evaluate associations between Hispanic ethnicity and exposure to deep sedation, controlling for patient characteristics.Results: Patients identified as Hispanic had approximately five times the odds of deep sedation (odds ratio, 4.98; 95% confidence interval, 2.02-12.28; P < 0.0001) on a given day, compared with non-Hispanic White patients. Hospitals with at least one enrolled Hispanic patient kept all enrolled patients deeply sedated longer than hospitals without any enrolled Hispanic patients (85.8% of ventilator-days vs. 65.5%; P < 0.001).Conclusions: Hispanic patients are at higher risk of exposure to deep sedation than non-Hispanic White patients. There is an urgent need to understand and address disparities in sedation delivery.

Effect of deep neuromuscular block on the quality of early recovery after sleeve gastrectomy in obese patients: a randomized controlled trial

BACKGROUND

Deep neuromuscular block (NMB) has been shown to improve surgical conditions and alleviate post-operative pain in bariatric surgery compared with moderate NMB. We hypothesized that deep NMB could also improve the quality of early recovery after laparoscopic sleeve gastrectomy (LSG).

METHODS

Eighty patients were randomized to receive either deep (post-tetanic count 1-3) or moderate (train-of-four count 1-3) NMB. The QoR-15 questionnaire was used to evaluate the quality of early recovery at 1 day before surgery (T0), 24 and 48 h after surgery (T2, T3). Additionally, we recorded diaphragm excursion (DE), postoperative pain, surgical condition, cumulative dose of analgesics, time of first flatus and ambulation, post-operative nausea and vomiting, time of tracheal tube removal and hospitalization time.

MAIN RESULTS

The quality of recovery was significantly better 24 h after surgery in patients who received a deep versus moderate block (114.4 ± 12.9 versus 102.1 ± 18.1). Diaphragm excursion was significantly greater in the deep NMB group when patients performed maximal inspiration at T2 and T3 (P < 0.05). Patients who underwent deep NMB reported lower visceral pain scores 40 min after surgery; additionally, these patients experienced lower pain during movement at T3 (P < 0.05). Optimal surgical conditions were rated in 87.5% and 64.6% of all measurements during deep and moderate NMB respectively (P < 0.001). The time to tracheal tube removal was significantly longer in the deep NMB group (P = 0.001). There were no differences in other outcomes.

CONCLUSION

In obese patients receiving deep NMB during LSG, we observed improved QoR-15 scores, greater diaphragmatic excursions, improved surgical conditions, and visceral pain scores were lower. More evidence is needed to determine the effects of deep NMB on these outcomes.

TRIAL REGISTRATION

ChiCTR2200065919. Date of retrospectively registered: 18/11/2022.

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.

A compressomyograph train of four monitoring device

The monitoring of the neuromuscular blockade is critical for patient's safety during and after surgery. The monitoring of neuromuscular blockade often requires the use of Train of Four (TOF) technique. During a TOF test two electrodes are attached to the ulnar nerve, and a series of four electric pulses are applied. The electrical stimulation causes the thumb to twitch, and the amount of twitch varies depending on the amount of neuromuscular blockade in patient's system. Current medical devices used to assist anesthesiologists to perform TOF monitoring often require free hand movement and do not provide accurate or reliable results. The goal of this work is to design, prototype and test a new medical device that provides reliable TOF results when thumb movement is restricted. A medical device that uses a pressurized catheter balloon to detect the response thumb twitch of the TOF test is created. An analytical model, numerical study, and mechanical finger testing were employed to create an optimum design. The design is tested through a pilot human subjects study. No significant correlation is reported with subjects' properties, including hand size.

Macrocycles and Acyclic Cucurbit[n]urils as Pseudo[2]catenane Partners for Long-Acting Neuromuscular Blocks and Rapid Reversal In Vivo

Long-acting neuromuscular blocks followed by rapid reversal may provide prolonged surgeries with improved conditions by omitting repetitive or continuous administration of the neuromuscular blocking agent (NMBA), eliminating residual neuromuscular block and minimizing postoperative recovery, which, however, is not clinically available. Here, we demonstrate that imidazolium-based macrocycles (IMCs) and acyclic cucurbit[n]urils (ACBs) can form such partners by functioning as long-acting NMBAs and rapid reversal agents through a pseudo[2]catenation mechanism based on stable complexation with Ka values of over 109 M-1. In vivo experiments with rats reveal that, at the dose of 2- and 3-fold ED90, one IMC attains a duration of action corresponding to 158 or 442 min for human adults, covering most of prolonged surgeries. The block can be reversed by one ACB with recovery time significantly shorter than that achieved by sugammadex for reversing the block of rocuronium, the clinically most widely used intermediate-acting NMBA.

Updated review on the use of neuromuscular blockade during intraoperative motor-evoked potential monitoring in the modern anesthesia era

Transcranial electrical stimulation motor-evoked potentials (Tc-MEP) monitoring is a common practice in neurosurgery to prevent postoperative neurological damage. However, the use of neuromuscular blocking agents (NMBAs) during Tc-MEP monitoring is a subject of controversy. In addition, the effectiveness of sugammadex, a selective reversal agent, in the context of Tc-MEP monitoring requires further investigation. This review aimed to clarify the considerations involved in achieving optimal Tc-MEP monitoring while ensuring patient safety. Preoperative patient selection, comorbidity assessment, motor power evaluation, and the nature of the planned surgery are critical factors. Accurate paralysis assessment, continuous NMBA infusion, and post-tetanic stimulation techniques are essential for achieving optimal partial NMB. The decision to administer an NMB during Tc-MEP monitoring necessitates a careful evaluation of the balance between accuracy and potential complications. This review emphasizes the challenges associated with NMB administration during Tc-MEP monitoring and highlights the need for personalized patient assessment.

Neuromuscular blockade and oxygenation changes during prone positioning in COVID-19

PURPOSE

Neuromuscular blockers (NMBs) are often used during prone positioning to facilitate mechanical ventilation in COVID-19 related ARDS. However, their impact on oxygenation is uncertain.

METHODS

Multi-centre observational study of invasively ventilated COVID-19 ARDS adults treated with prone positioning. We collected data on baseline characteristics, prone positioning, NMB use and patient outcome. We assessed arterial blood gas data during supine and prone positioning and after return to the supine position.

RESULTS

We studied 548 prone episodes in 220 patients (mean age 54 years, 61% male) of whom 164 (75%) received NMBs. Mean PaO2:FiO2 (P/F ratio) during the first prone episode with NMBs reached 208 ± 63 mmHg compared with 161 ± 66 mmHg without NMBs (Δmean = 47 ± 5 mmHg) for an absolute increase from baseline of 76 ± 56 mmHg versus 55 ± 56 mmHg (padj < 0.001). The mean P/F ratio on return to the supine position was 190 ± 63 mmHg in the NMB group versus 141 ± 64 mmHg in the non-NMB group for an absolute increase from baseline of 59 ± 58 mmHg versus 34 ± 56 mmHg (padj < 0.001).

CONCLUSION

During prone positioning, NMB is associated with increased oxygenation compared to non-NMB therapy, with a sustained effect on return to the supine position. These findings may help guide the use of NMB during prone positioning in COVID-19 ARDS.

Quantitative evaluation of the biomechanical and viscoelastic properties of the dog patellar tendon in response to neuromuscular blockade at different stifle angles

The patellar tendon (PT) is crucial for maintaining stability and facilitating movement in the stifle joint. Elastography has been recognized as a prominent method for evaluating PT properties in humans and dogs. The utilization of oscillation methods in canine studies remains limited despite their extensive documentation in human studies. Our study represents the first effort to quantitatively assess and compare the effects of muscle relaxant on the biomechanical and viscoelastic characteristics of the PT at varying stifle angles in living dogs. Five healthy female beagles were used in this study. Biomechanical (tone, stiffness, and decrement) and viscoelastic (relaxation time and creep) properties of the PT were measured using MyotonPRO (Myoton Ltd, Estonia) prior to and following administration of rocuronium (0.5 mg/kg/body weight) at normal, extended, and flexed positions. Rocuronium was selected for its safety, controllability, and widespread clinical use in veterinary anesthesia. Two-way analysis of variance showed that tone, stiffness, and decrement were significantly higher (P < 0.001) in the control group than in the muscle relaxation group. At the same time, relaxation time and creep were significantly lower (P < 0.001) in the control group than in the muscle relaxation group. The findings indicate that stifle angle position and muscle rexalant administration fundamentally alter the biomechanical loading conditions of the PT, leading to changes in its viscoelastic properties. Therefore, this novel quantitative data could benefit clinical settings that necessitate accurate and objective methods for risk identification and monitoring PT biomechanics in dogs.

Is adamgammadex the brother of sugammadex or the next generation of reversal agent?

Sugammadex is now in widespread use to reverse the neuromuscular blocking effects of rocuronium. Adverse effects from sugammadex are rare, but anaphylactic and cardiovascular reactions to the drug have been reported. In an attempt to reduce such side-effects, a modified gamma-cyclodextrin, adamgammadex, has been developed. Phase 3 clinical trials suggest that it is slightly less potent than sugammadex and has a non-inferior speed of onset. In a multicentre trial of 310 patients, there was a suggestion of a lower incidence of allergic responses and recurarisation after adamgammadex compared with sugammadex. The clinical implications of this study are discussed in this editorial.

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).

Neuromuscular end-point predictive capability of published rocuronium pharmacokinetic/pharmacodynamic models: An observational trial

BACKGROUND

Objective neuromuscular monitoring remains the single most reliable method to ensure optimal perioperative neuromuscular management. Nevertheless, the prediction of clinical neuromuscular endpoints by means of Pharmacokinetic (PK) and Pharmacodynamic (PD) modelling has the potential to complement monitoring and improve perioperative neuromuscular management.s STUDY OBJECTIVE: The present study aims to assess the performance of published Rocuronium PK/PD models in predicting intraoperative Train-of-four (TOF) ratios when benchmarked against electromyographic TOF measurements.

DESIGN

Observational trial.

SETTING

Tertiary Belgian hospital, from August 2020 up to September 2021.

PATIENTS AND INTERVENTIONS

Seventy-four patients undergoing general anaesthesia for elective surgery requiring the administration of rocuronium and subject to continuous EMG neuromuscular monitoring were included. PK/PD-simulated TOF ratios were plotted and synchronised with their measured electromyographic counterparts and their differences analysed by means of Predictive Error derivatives (Varvel criteria).

MAIN RESULTS

Published rocuronium PK/PD models overestimated clinically registered TOF ratios. The models of Wierda, Szenohradszky, Cooper, Alvarez-Gomez and McCoy showed significant predictive consistency between themselves, displaying Median Absolute Performance Errors between 38% and 41%, and intra-individual differences (Wobble) between 14 and 15%. The Kleijn model outperformed the former with a lower Median Absolute Performance Error (16%, 95%CI [0.01; 57]) and Wobble (11%, 95%CI [0.01; 34]). All models displayed considerably wide 95% confidence intervals for all performance metrics, suggesting a significantly variable performance.

CONCLUSIONS

Simulated TOF ratios based on published PK/PD models do not accurately predict real intraoperative TOF ratio dynamics.

TRIAL REGISTRATION

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

Response of the GE Entropy™ monitor to neuromuscular block in awake volunteers

BACKGROUND

The GE Entropy™ monitor analyses the frontal electroencephalogram (EEG) and generates two indices intended to represent the degree of anaesthetic drug effect on the brain. It is frequently used in the context of neuromuscular block. We have shown that a similar device, the Bispectral Index monitor (BIS), does not generate correct values in awake volunteers when neuromuscular blocking drugs are administered.

METHODS

We replayed the EEGs recorded during awake paralysis from the original study to an Entropy monitor via a calibrated electronic playback system. Each EEG was replayed 30 times to evaluate the consistency of the Entropy output.

RESULTS

Both State Entropy and Response Entropy decreased during periods of neuromuscular block to values consistent with anaesthesia, despite there being no change in conscious state (State Entropy <60 in eight of nine rocuronium trials and nine of 10 suxamethonium trials). Entropy values did not return to pre-test levels until after the return of movement. Entropy did not generate exactly the same results when the same EEG was replayed multiple times, which is primarily because of a cyclical state within the Entropy system itself.

CONCLUSIONS

The GE Entropy™ monitor requires muscle activity to generate correct values in an awake subject. It could therefore be unreliable at detecting awareness in patients who have been given neuromuscular blocking drugs. In addition, Entropy does not generate the same result each time it is presented with the same EEG.

Effect of Sevoflurane on the Deep Neuromuscular Blockade in Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy: A Single Center Prospective Randomized Controlled Study

Objective

Our study aimed to demonstrate that the combination of sevoflurane inhalation with continuous intravenous anesthesia can effectively reduce the dosage of muscle relaxants, shorten extubation time under anesthesia while meeting the requirements of laparoscopic deep neuromuscular block (dNMB) in obese patients. Additionally, we sought to assess the potential reduction in postoperative residual muscle relaxants.

Methods

Fifty-nine patients were randomly assigned. Anesthesia-related variables, such as anesthetics dosages, muscle relaxant effective time, clinical muscle relaxant time, muscle relaxant in vivo action time, muscle relaxant recovery time, body movement times, and extubation duration were recorded. Surgery-related variables (the Leiden-Surgical Rating Scale (L-SRS), duration of the procedure) were recorded. Pain was measured using the visual analog scale (VAS) score before leaving the PACU. The duration of the PACU stay and patients' satisfaction levels in the PACU were also recorded.

Results

Patients who inhaled sevoflurane during the operation required a lower dosage of muscle relaxant to achieve the same deep neuromuscular block (dNMB) effect. The time from stopping the rocuronium pump to T1 recovery of 90% was shorter, and the time for T1 to recover from 25% to 75% was faster among patients who inhaled sevoflurane during the operation. Furthermore, the sevoflurane combined with continuous intravenous anesthesia group exhibited a shorter extubation time for obese patients undergoing laparoscopic bariatric surgery, along with a reduced risk of experiencing hypoxemia and a shorter observation time in the PACU.

Conclusion

Inhaling sevoflurane combined with continuous intravenous anesthesia during the operation effectively reduces the dosage of muscle relaxant required to achieve the same deep neuromuscular block (dNMB) effect. Additionally, this approach significantly shortens the extubation time for obese patients undergoing laparoscopic bariatric surgery and reduces the risk of experiencing hypoxemia, along with reducing the observation time in the PACU.

Precipitation of sugammadex with nicardipine and labetalol: A laboratory research

There is a paucity of clinical data about whether sugammadex forms precipitates with other medications. This laboratory experimental study was performed to determine the drugs that produce precipitates with sugammadex. Samples of 1 ml of sugammadex were prepared in transparent cylinders, to which 1 ml of test drugs (rocuronium, neostigmine, glycopyrrolate, atropine, nitroglycerin, dobutamine, dopamine, epinephrine, vasopressin, norepinephrine, phenylephrine, ephedrine, esmolol, nicardipine, and labetalol) was added. The precipitation reaction was observed visually and via light microscope. The pH of each drugs before and after mixing with sugammadex was measured. White crystals were formed when sugammadex was mixed with nicardipine or labetalol. Sugammadex formed precipitate when mixed with nicardipine or labetalol. Sufficient fluid flushing is required between injections of each drug to prevent these reactions.

Spinal Muscular Atrophy Type III Recognized After Delayed Recovery From Neuromuscular Blockade After an Orthognathic Surgery

Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disease characterized by the degeneration of alpha motor neurons in the spinal cord, resulting in progressive proximal muscle weakness and paralysis. SMA is classified into types I-IV based on the age at symptom onset or maximum motor function achieved, and its clinical manifestations vary. SMA affects maxillofacial growth because of muscle dysfunction and results in abnormal maxillofacial morphology. In addition, definitive diagnosis is not often made because of the older onset age and symptoms are rarely severe. Therefore, the possibility of undiagnosed SMA in craniofacial surgeries must be considered. This report described a case of an SMA type III recognized after delayed recovery from the neuromuscular blockade in an orthognathic surgery under general anesthesia.

Effect of sugammadex on processed EEG parameters in patients undergoing robot-assisted radical prostatectomy

BACKGROUND

Sugammadex has been associated with increases in the bispectral index (BIS). We evaluated the effects of sugammadex administration on quantitative electroencephalographic (EEG) and electromyographic (EMG) measures.

METHODS

We performed a prospective observational study of adult male patients undergoing robot-assisted radical prostatectomy. All patients received a sevoflurane-based general anaesthetic and a continuous infusion of rocuronium, which was reversed with 2 mg kg-1 of sugammadex i.v. BIS, EEG, and EMG measures were captured with the BIS Vista™ monitor.

RESULTS

Twenty-five patients were included in this study. Compared with baseline, BIS increased at 4-6 min (β coefficient: 3.63; 95% confidence interval [CI]: 2.22-5.04; P<0.001), spectral edge frequency 95 (SEF95) increased at 2-4 min (β coefficient: 0.29; 95% CI: 0.05-0.52; P=0.016) and 4-6 min (β coefficient: 0.71; 95% CI: 0.47-0.94; P<0.001), and EMG increased at 4-6 min (β coefficient: 1.91; 95% CI: 1.00-2.81; P<0.001) after sugammadex administration. Compared with baseline, increased beta power was observed at 2-4 min (β coefficient: 93; 95% CI: 1-185; P=0.046) and 4-6 min (β coefficient: 208; 95% CI: 116-300; P<0.001), and decreased delta power was observed at 4-6 min (β coefficient: -526.72; 95% CI: -778 to -276; P<0.001) after sugammadex administration. Neither SEF95 nor frequency band data analysis adjusted for EMG showed substantial differences. None of the patients showed clinical signs of awakening.

CONCLUSIONS

After neuromuscular block reversal with 2 mg kg-1 sugammadex, BIS, SEF95, EMG, and beta power showed small but statistically significant increases over time, while delta power decreased.

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.

Pain Assessment and Management for a Chemically Paralyzed Child Receiving Mechanical Ventilation

BACKGROUND

Pain assessment in the pediatric intensive care unit (PICU) is complex, specifically for children receiving mechanical ventilation who require neuromuscular blockade (NMB). No valid pain assessment method exists for this population. Guidelines are limited to using physiologic variables; it remains unknown how nurses are assessing and managing pain for this population in practice.

OBJECTIVES

To describe how PICU nurses are assessing and managing pain for children who require NMB.

METHODS

A cross-sectional quantitative design was used with an electronic survey. Nurses were asked to respond to 4 written vignettes depicting a child who required NMB and had a painful procedure, physiologic cues, both, or neither.

RESULTS

A total of 107 PICU nurses answered the survey. Nurses primarily used behavioral assessment scales (61.0%) to assess the child's pain. All nurses reported that physiologic variables are either moderately or extremely important, and 27.3% of nurses used the phrase "assume pain present" formally at their organization. When physiologic cues were present, the odds of a nurse intervening with a pain intervention were 23.3 times (95% CI, 11.39-53.92; P < .001) higher than when such cues were absent.

CONCLUSIONS

These results demonstrate variation in how nurses assess pain for a child who requires NMB. The focus remains on behavioral assessment scales, which are not valid for this population. When intervening with a pain intervention, nurses relied on physiologic variables. Decision support tools to aid nurses in conducting an effective pain assessment and subsequent management need to be created.

Deep versus moderate neuromuscular blockade during total hip arthroplasty to improve postoperative quality of recovery and immune function: protocol for a randomised controlled study

INTRODUCTION

There is accumulating evidence that deep neuromuscular blockade (NMB) improves intraoperative surgical conditions during laparoscopic surgery. Studies investigating the effects of deep NMB in open surgery are scarce. In theory, by limiting surgical damage through deeper muscle relaxation, postoperative inflammation and concomitant immune suppression can be reduced. Therefore, this study will investigate the effects of deep NMB during total hip arthroplasty, which demands a relatively large exposure of the hip joint through and in between muscles.

METHODS AND ANALYSIS

This study is a monocentre blinded randomised controlled trial in 100 patients undergoing total hip arthroplasty under general anaesthesia. Patients will be randomised in a 1:1 fashion to an intervention group of intraoperative deep NMB (a post-tetanic count of 1-2) or a control group receiving moderate NMB (a train-of-four count of 1-2). NMB will be achieved by continuous or bolus administration of rocuronium, respectively. The primary endpoint is the quality of recovery at postoperative day 1 measured by the Quality of Recovery-40 Questionnaire, analysed by Analysis of Variance. The secondary endpoint is postoperative innate immune function, measured by ex vivo production capacity of tumour necrosis factor and interleukin-1β on endotoxin stimulation of whole blood.

ETHICS AND DISSEMINATION

Ethical approval for this study was granted by the Medical Ethics Committee 'METC Oost-Nederland' (reference number 2022-15754). Informed consent will be obtained prior to study participation. Study results will be published in an international peer-reviewed journal.

TRIAL REGISTRATION NUMBERS

ClinicalTrials.gov Registry (NCT05562999) and EudraCT Registry (2022-002451-19).

Reversal of neuromuscular block: what are the costs?

Patients requiring neuromuscular block for anaesthesia have a higher risk of adverse postoperative outcomes. The choice of reversal drug and its corresponding dose is critical for improving clinical outcomes. Although drug costs are higher for sugammadex relative to neostigmine, additional factors need to be considered when choosing one drug over the other. New data from a recent study in the British Journal of Anaesthesia indicate cost advantages for sugammadex in low-risk and ambulatory patients, but for neostigmine in high-risk patients. These findings highlight the need to take local and temporal factors into consideration in addition to clinical effectiveness when performing cost analyses for administrative decision-making.

Comparison of onset of neuromuscular blockade with electromyographic and acceleromyographic monitoring: a prospective clinical trial

BACKGROUND

Reliable devices that quantitatively monitor the level of neuromuscular blockade after neuromuscular blocking agents' administration are crucial. Electromyography and acceleromyography are two monitoring modalities commonly used in clinical practice. The primary outcome of this study is to compare the onset of neuromuscular blockade, defined as a Train-Of-Four Count (TOFC) equal to 0, as measured by an electromyography-based device (TetraGraph) and an acceleromyography-based device (TOFscan). The secondary outcome was to compare intubating conditions when one of these two devices reached a TOFC equal to 0.

METHODS

One hundred adult patients scheduled for elective surgery requiring neuromuscular blockade were enrolled. Prior to induction of anesthesia, TetraGraph electrodes were placed over the forearm of patients' dominant/non-dominant hand based on randomization and TOFscan electrodes placed on the contralateral forearm. Intraoperative neuromuscular blocking agent dose was standardized to 0.5 mg.kg-1 of rocuronium. After baseline values were obtained, objective measurements were recorded every 20 seconds and intubation was performed using video laryngoscopy once either device displayed a TOFC = 0. The anesthesia provider was then surveyed about intubating conditions.

RESULTS

Baseline TetraGraph train-of-four ratios were higher than those obtained with TOFscan (Median: 1.02 [0.88, 1.20] vs. 1.00 [0.64, 1.01], respectively, p < 0.001). The time to reach a TOFC = 0 was significantly longer when measured with TetraGraph compared to TOFscan (Median: 160 [40, 900] vs. 120 [60, 300] seconds, respectively, p < 0.001). There was no significant difference in intubating conditions when either device was used to determine the timing of endotracheal intubation.

CONCLUSIONS

The onset of neuromuscular blockade was longer when measured with TetraGraph than TOFscan, and a train-of-four count of zero in either device was a useful indicator for adequate intubating conditions.

CLINICAL TRIAL NUMBER AND REGISTRY

URL NCT05120999, https://clinicaltrials.gov/ct2/show/NCT05120999.

Short-Acting Neuromuscular Blockade Improves Inter-rater Reliability of Median Somatosensory Evoked Potentials in Post-cardiac arrest Prognostication

BACKGROUND

Although median nerve somatosensory evoked potentials are routinely used for prognostication in comatose cardiac arrest survivors, myogenic artifact can reduce inter-rater reliability, leading to unreliable or inaccurate results. To minimize this risk, we determined the benefit of neuromuscular blockade agents in improving the inter-rater reliability and signal-to-noise ratio of SSEPs in the context of prognostication.

METHODS

Thirty comatose survivors of cardiac arrest were enrolled in the study, following the request from an intensivist to complete an SSEP for prognostication. Right and left median nerve SSEPs were obtained from each patient, before and after administration of an NMB agent. Clinical histories and outcomes were retrospectively reviewed. The SSEP recordings before and after NMB were randomized and reviewed by five blinded raters, who assessed the latency and amplitude of cortical and noncortical potentials (vs. absence of response) as well as the diagnostic quality of cortical recordings. The inter-rater reliability of SSEP interpretation before and after NMB was compared via Fleiss' κ score.

RESULTS

Following NMB administration, Fleiss' κ score for cortical SSEP interpretation significantly improved from 0.37 to 0.60, corresponding to greater agreement among raters. The raters were also less likely to report the cortical recordings as nondiagnostic following NMB (40.7% nondiagnostic SSEPs pre-NMB; 17% post-NMB). The SNR significantly improved following NMB, especially when the pre-NMB SNR was low (< 10 dB). Across the raters, there were three patients whose SSEP interpretation changed from bilaterally absent to bilaterally present after NMB was administered (potential false positives without NMB).

CONCLUSIONS

NMB significantly improves the inter-rater reliability and SNR of median SSEPs for prognostication among comatose cardiac arrest survivors. To ensure the most reliable prognostic information in comatose post-cardiac arrest survivors, pharmacologic paralysis should be consistently used before recording SSEPs.

The effect of rocuronium priming dose based on actual versus corrected body weight in modified rapid sequence intubation

Background

Rapid sequence intubation (RSI) is a technique that allows patients to be quickly intubated and have the airway secured.

Aims

The purpose of this study was to investigate the effect of rocuronium priming and intubation dose calculated according to actual body weight (ABW) or corrected body weight (CBW) on the neuromuscular block and intubation quality in rapid sequence induction and intubation (RSII).

Patients and Methods

This prospective randomized, double-blind study was conducted on a total of 60 patients randomized into two groups using the closed-envelope method between January 2021 and December 2021, with 30 individuals in each group. In group 1, CBW was used with the formula to calculate the neuromuscular blocking drug (NMBD) dose. The ABW of patients was used to calculate the NMBD dose in group 2.

Results

The data of 50 female patients who underwent group 1 (CBW, n = 25) and group 2 (ABW, n = 25) were analyzed. Age, weight, height, body mass index (BMI), quality of laryngoscopy, post-priming side effects, mean arterial pressure (MAP), and heart rate (HR) values did not differ across the groups. When train-of-four (TOF) values, priming and intubation dose, and laryngoscopy time were compared, a statistically significant difference was found between the two groups of TOF count (TOF C) 1 (the duration of action).

Conclusion

This study suggests that the application of rocuronium priming and intubation dose according to CBW in RSII, especially during the pandemic, provided similar intubation conditions as the application according to ABW, while its shorter duration of action shows that it can be preferred, especially in short-term surgical cases.

Comparison of visual and electromyographic assessments with train-of-four stimulation of the ulnar nerve: a prospective cohort study

PURPOSE

The use of a peripheral nerve stimulator to assess the level of neuromuscular blockade tasks the anesthesia clinician with subjectively assessing the response to neurostimulation. In contrast, objective neuromuscular monitors provide quantitative information. The purpose of this study was to compare subjective evaluations from a peripheral nerve stimulator with objective measurements of neurostimulation responses from a quantitative monitor.

METHODS

Patients were enrolled preoperatively, and intraoperative neuromuscular blockade management was at the discretion of the anesthesiologist. Electromyography electrodes were placed over the dominant or nondominant arm in a randomized fashion. Following onset of nondepolarizing neuromuscular blockade, the ulnar nerve was stimulated, the response was measured with electromyography, and anesthesia clinicians, who were blinded to the objective measurements, subjectively (visually) evaluated the response to neurostimulation.

RESULTS

Fifty patients were enrolled and 666 neurostimulations were performed at 333 different time points. Anesthesia clinicians subjectively overestimated the response of the adductor pollicis muscle following neurostimulation of the ulnar nerve 155/333 (47%) of the time when compared with objective electromyographic measurements. When subjective evaluations and objective measurements differed to any degree, subjective evaluations were higher than objective measurements 155/166 (92%) of the time (95% CI, 87 to 95; P < 0.001), representing significant evidence that subjective evaluation overestimates the response to train-of-four stimulation.

CONCLUSIONS

Subjective observations of a "twitch" do not consistently correspond to objective measurements of neuromuscular blockade with electromyography. Subjective evaluation overestimates the response to neurostimulation and may be unreliable for determining the depth of block or confirming adequate recovery.

Reliability of submaximal stimulation for the train-of-four test using acceleromyography and electromyography with individualized stimulation currents

PURPOSE

The supramaximal stimulation (SMS) of the TOF test causes uncomfortable sensations in patients. We aimed to determine whether the submaximal stimulation would be reliable in TOF tests with reduced painful sensation.

METHODS

The accelomyography (AMG) and electromyography (EMG) monitor was applied at each arm and general anesthesia was induced and maintained by total intravenous anesthesia. At extubation, we conducted TOF test three times at each of four different currents: SMS, 70% SMS, 50% SMS, and 30% SMS. The same procedure was performed in the postanesthesia care unit (PACU) only with EMG, and the pain scores on the numerical rating scale (NRS) during the tests were recorded.

RESULTS

A total of 36 patients were enrolled. At extubation, TOF ratios with SMS in AMG and EMG were 112.0 ± 13.1% and 93.7 ± 8.9%, respectively. There were no significant differences in TOF ratios between the SMS and lower stimulation intensities. However, 30% and 50% SMS showed significantly higher rates of the unmeasurable results of tests in the PACU. In terms of the stimulation pain, NRS showed a downward pattern as the current decreased and was significantly lower at 50% and 30% SMS than the NRS at SMS.

CONCLUSION

The TOF test with submaximal stimulation is still reliable and can reduce stimulation pain. Considering the importance of the TOF results in determining extubation, the authors suggest the minimal current for the TOF test as 70% SMS.

Changes in bispectral index and patient state index during sugammadex reversal of neuromuscular blockade under steady-state sevoflurane anesthesia

Few studies have investigated the changes in patient state index (PSI) and bispectral index (BIS) in response to abrupt increase in electromyographic (EMG) activity. These were performed using intravenous anesthetics or reversal agents for neuromuscular blockade (NMB) other than sugammadex. We compared the changes in BIS and PSI values caused by the sugammadex reversal of NMB during steady-state sevoflurane anesthesia. We enrolled 50 patients with American Society of Anesthesiologists physical status 1 and 2. At the end of the surgery, we administered 2 mg kg-1 sugammadex while maintaining sevoflurane for a 10-min study period. The changes in BIS and PSI from baseline (T0) to train of four ratio of 90% were not significantly different (median difference 0; 95% CI - 3 to 2; P = 0.83), neither were the changes in BIS and PSI values from T0 to their maximum values (median difference 1; 95% CI - 1 to 4; P = 0.53). Maximum BIS and PSI were significantly higher than their baseline values (median difference 6; 95% CI 4-9; P < 0.001 and median difference 5; 95% CI 3-6; P < 0.001, respectively). We found weak positive correlations between BIS and BIS-EMG (r = 0.12, P = 0.01), as well as PSI and PSI-EMG (r = 0.25, P < 0.001). Both PSI and BIS were affected to some extent by EMG artifacts after sugammadex administration.

Analgesia, Sedation, and Neuromuscular Blockade in Infants with Congenital Diaphragmatic Hernia

OBJECTIVE

The aim of this study was to describe the use, duration, and intercenter variation of analgesia and sedation in infants with congenital diaphragmatic hernia (CDH).

STUDY DESIGN

This is a retrospective analysis of analgesia, sedation, and neuromuscular blockade use in neonates with CDH. Patient data from 2010 to 2016 were abstracted from the Children's Hospitals Neonatal Database and linked to the Pediatric Health Information System. Patients were excluded if they also had non-CDH conditions likely to affect the use of the study medications.

RESULTS

A total of 1,063 patients were identified, 81% survived, and 30% were treated with extracorporeal membrane oxygenation (ECMO). Opioid (99.8%), sedative (93.4%), and neuromuscular blockade (87.9%) use was common. Frequency of use was higher and duration was longer among CDH patients treated with ECMO. Unadjusted duration of use varied 5.6-fold for benzodiazepines (median: 14 days) and 7.4-fold for opioids (median: 16 days). Risk-adjusted duration of use varied among centers, and prolonged use of both opioids and benzodiazepines ≥5 days was associated with increased mortality (p < 0.001) and longer length of stay (p < 0.001). Use of sedation or neuromuscular blockade prior to or after surgery was each associated with increased mortality (p ≤ 0.01).

CONCLUSION

Opioids, sedatives, and neuromuscular blockade were used commonly in infants with CDH with variable duration across centers. Prolonged combined use ≥5 days is associated with mortality.

KEY POINTS

· Use of analgesia and sedation varies across children's hospital NICUs.. · Prolonged opioid and benzodiazepine use is associated with increased mortality.. · Postsurgery sedation and neuromuscular blockade are associated with mortality..

Recall of Awareness During Paralysis Among ED Patients Undergoing Tracheal Intubation

BACKGROUND

Critically ill patients sometimes remember periods of neuromuscular blockade.

RESEARCH QUESTION

What is the prevalence of recalled awareness during paralysis in patients who underwent emergency tracheal intubation and mechanical ventilation, and what clinical variables are associated with this outcome?

STUDY DESIGN AND METHODS

This study analyzed data from a prospectively collected continuous quality improvement database of emergency tracheal intubation in an urban, county hospital. Patients who received a neuromuscular blocking agent to facilitate emergency tracheal intubation in the ED were included. The database contained details of intubation management, including medications received and patient mental status prior to intubation. Patient recall of awareness of paralysis was assessed by trained staff during an in-person interview following extubation using a modified Brice questionnaire. For this analysis, three expert reviewers used these data to adjudicate whether patients may have had awareness of paralysis, the primary outcome. A logistic regression model was constructed to determine whether clinical variables were associated with the primary outcome.

RESULTS

A total of 886 patients were analyzed. There were 66 patients (7.4%; 95% CI, 5.8-9.4) determined to possibly (61 patients) or definitely (5 patients) have experienced and recalled awareness of paralysis. A logistic regression model revealed that a decreased level of consciousness prior to intubation was associated with lower odds of awareness (adjusted OR, 0.39; 95% CI, 0.22-0.69), whereas the class of neuromuscular blocking agent used, sedative used, preintubation shock index, and postintubation sedation were not significantly associated with recall of this outcome.

INTERPRETATION

Among patients intubated emergently using a neuromuscular blocking agent, 7.4% of patients recalled awareness without being able to move, which was more likely when patients had a normal level of consciousness prior to intubation.

An appraisal of neostigmine versus sugammadex for neuromuscular blockade reversal in patients with a prior heart transplant

INTRODUCTION

Heart transplant recipients present unique perioperative challenges for surgery. Specifically, autonomic system denervation has significant implications for commonly used perioperative drugs. This study investigates neuromuscular blocking antagonists in this population when undergoing subsequent non-cardiac surgery.

MATERIAL AND METHODS

A retrospective review was performed for the period 2015-2019 across our health care enterprise. Patients with previous orthotopic heart transplant and subsequent non-cardiac surgery were identified. A total of 185 patients were found, 67 receiving neostigmine (NEO) and 118 receiving sugammadex (SGX). Information of patient characteristics, prior heart transplant, and subsequent non-cardiac surgery was collected. Our primary outcome was the incidence of bradycardia (heart rate < 60 bpm) and/or hypotension (mean blood pressure (MAP) < 65 mmHg) following neuromuscular blockade reversal. Secondary outcomes included need of intra-operative inotropic agents, arrhythmia, cardiac arrest, hospital length of stay (hLOS), ICU admission, and death within 30 postoperative days.

RESULTS

In unadjusted analysis, no significant differences were found between the two groups in change in heart rate [0 (-26, 14) vs. 1 (-19, 10), P = 0.59], change in MAP [0 (-22, 28) vs. 0 (-40, 47), P = 0.96], hLOS [2 days (1, 72) vs. 2 (0, 161), P = 0.92], or intraoperative hypotension [4 (6.0%) vs. 5 (4.2%), OR = 0.70, P = 0.60] for NEO and SGX respectively. After multivariable analysis, the results were similar for change in heart rate ( P = 0.59) and MAP ( P = 0.90).

CONCLUSIONS

No significant differences in the incidence of bradycardia and hypotension were found in the NEO versus SGX groups. NEO and SGX may have similar safety profiles in patients with prior heart transplant undergoing non-cardiac surgery.