Recurarization after sugammadex reversal in an obese patient

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.

Comparison of Different Weight Scalars to Dose Sugammadex for the Reversal of Neuromuscular Blockade in Morbidly Obese Patients: A Systematic Review

This systematic review was conducted to evaluate the optimal weight scalar to dose sugammadex in a morbidly obese (MO) patient population (BMI≥40 kg/m2). The primary outcome was recovery time from moderate neuromuscular blockade (NMB) or deep NMB. Secondary outcomes included time to extubation and incidence of postoperative residual curarization (PORC). Eight randomized controlled trials (RCTs) involving 645 participants were included. The different dose scalars included were total body weight (TBW), ideal body weight (IBW), 20% corrected body weight (CBW) and 40% CBW). A dose of 2 mg/kg of sugammadex based on 40% CBW and a 4 mg/kg dose of sugammadex based on 40% CBW provide a reliable and timely reversal of moderate and deep NMB respectively in the MO patients.

Improved Reliability of Electromyography-Based Neuromuscular Monitoring During Laparoscopic Surgery Achieved by the Modified Attachment Method for Nihon-Kohden NM-345Y™ Stimulating Electrodes: A Case Report

Neuromuscular monitoring is crucial during the administration of neuromuscular blocking agents owing to individual variations in their effects. In electromyography (EMG)-based neuromuscular monitoring using the EMG electrodes (NM-345Y™, Nihon-Kohden Corporation, Tokyo, Japan) following the manufacturer-recommended attachment method, the accuracy of neuromuscular monitoring may be reduced when forearm limb position is changed. We previously devised a novel attachment method for NM-345Y™ stimulating electrodes in adult volunteers to maintain stable monitoring accuracy despite changes in forearm position. Its effectiveness in clinical practice was evaluated by conducting a descriptive study on a 52-year-old woman undergoing laparoscopic uterine surgery. NM-345Y™ electrodes were attached to each forearm following the manufacturer's recommendations (Pattern N) and our novel method (Pattern C). In Pattern C, NM-345Y™ was attached without ultrasound guidance so that the ulnar nerve crossed the line connecting the centers of the anode and cathode of the stimulating electrode. Pattern C exhibited consistent EMG-based monitoring accuracy even with changes in forearm position despite a smaller stimulus current value at calibration. Additionally, Pattern C displayed reliable recovery of the train-of-four (TOF) response after sugammadex administration in the original forearm position, with no observed adverse events. In contrast, Pattern N showed unstable monitoring accuracy after forearm position changes, highlighting the danger of imprecise EMG-based neuromuscular monitoring during the administration of neuromuscular blocking agents. The study's strength lies in identifying Pattern C, where the ulnar nerve crosses the line connecting the anode and cathode, significantly enhancing monitoring accuracy. This novel attachment method holds promise to improve EMG-based neuromuscular monitoring precision in surgery involving forearm limb position changes, although further research is required to assess its utility comprehensively.

Cardiac Arrest in the Post-anesthesia Care Unit (PACU): Postoperative Recurrence of Neuromuscular Block After Sugammadex Reversal

Sugammadex has transformed clinical practice by enabling the rapid reversal of rocuronium-induced neuromuscular block (NMB) at any depth. We present a case of cardiac arrest following postoperative recurarization despite the sugammadex-induced transient reversal of NMB. Despite its proven clinical reliability, this case highlights the often overlooked aspects that must be considered when using this drug. An 84-year-old male patient was scheduled for a laparoscopic partial gastrectomy for gastric cancer. At the end of the procedure, reversal of NMB was evidenced by an acceleromyographic train-of-four (TOF) ratio of ≥0.9 following sugammadex administration. In the post-anesthesia care unit (PACU), pulseless electrical activity was perceived, with a regression of TOF count to 1. After providing successful advanced cardiac life support, additional sugammadex administration led to uneventful extubation. When the concentration of free rocuronium decreases in the central compartment following sugammadex administration, redistribution of rocuronium from the peripheral to the central and effect-site compartments may cause recurarization. Special care is required in cases involving obese and elderly patients as well as those with renal impairment or hypothermia. To provide effective and predictable reversal of NMB, proper use of sugammadex should be pursued, including adequate dosing and monitoring.

Analysis of the factors contributing to residual weakness after sugammadex administration in pediatric patients under 2 years of age

BACKGROUND

Sugammadex reverses the neuromuscular blockade induced by rocuronium and vecuronium and is approved by the U.S. Food and Drug Administration for use in patients aged over 2 years. There is, however, a paucity of data regarding its dosing profile in infants and children younger than 2 years.

AIMS

The aim of this study was to assess the risk of recurarization, or re-paralysis, in children under 2 years of age to increase awareness on the importance of appropriate neuromuscular blocked monitoring and reversal.

METHODS

All patients aged ≤24 months who underwent an operative procedure at a tertiary medical center between January 1, 2018, and December 31, 2021, and received both rocuronium for neuromuscular blockade and sugammadex for neuromuscular blockade reversal, were identified in the electronic medical record. Patients were excluded from analysis if they (1) received vecuronium, cisatracurium, atracurium, or succinylcholine for neuromuscular blockade, (2) received neostigmine for reversal, or (3) underwent more than one operation within 24 h. We performed a survival analysis of sugammadex redose using a Cox proportional hazards model.

RESULTS

We reviewed 2923 records. Sugammadex was redosed in 123 (4.2%) cases. The median [IQR] time to redose was 7 [4-17] min, and the median [IQR] amount of redose administered was 2.74 [1.96-3.99] mg/kg. Increasing patient age (p < .01) and weight (p < .01) were associated with reduced hazard rate of sugammadex redose. For a patient of median weight, increasing age from 3 to 13 months was associated with a 53% risk reduction (HR: 0.47; 95% CI: 0.24-0.91). For a patient of median age, increasing weight from 4.7 to 9.2 kg was associated with 41% risk reduction (HR: 0.59; 95% CI: 0.32-1.07). We failed to detect any other associations.

CONCLUSIONS

In this single-center, retrospective cohort study of pediatric surgery patients, there was an association between the hazard of sugammadex redose with both increased age and weight.

Effects of the attachment method of the stimulating electrodes Nihon-Kohden NM-345Y™ and changes in forearm position on stimulus current values during calibration in electromyography-based neuromuscular monitoring: a single-center experimental study

PURPOSE

The traditionally recommended method for attaching electromyography (EMG) electrodes (NM-345Y™) during EMG-based neuromuscular monitoring developed by Nihon-Kohden may decrease the monitoring accuracy when forearm limb position changes. This study investigated methods for attaching stimulating electrodes that maintained stable EMG-based neuromuscular monitoring accuracy, regardless of forearm limb position changes.

METHODS

This single-center experimental study recruited 28 healthy adults from October 2022 to December 2022. The NM-345Y™ was attached to the forearm using three patterns: Pattern N, electrodes attached according to the attachment pattern recommended by Nihon-Kohden; Pattern U, electrodes attached along the ulnar nerve identified using an ultrasound device; Pattern C, electrodes attached where the ulnar nerve crosses the line connecting the centers of the anode and cathode of the stimulating electrodes. The stimulus current values during calibration were measured at three forearm positions for each attachment pattern: supination 90 degrees; pronation 0 degrees; pronation 90 degrees. The differences in stimulus current values caused by forearm position changes were calculated as the difference between values at supination 90 degrees and pronation 0 degrees and between values at supination 90 degrees and pronation 90 degrees.

RESULTS

Pattern C showed significantly smaller differences than Pattern N between the stimulus current values at supination 90 degrees and pronation 0 degrees (p = 0.018) and between the stimulus current values at supination 90 degrees and pronation 90 degrees (p = 0.008).

CONCLUSION

Crossing the ulnar nerve with the line connecting the anode and cathode of the stimulating electrodes may stabilize EMG-based neuromuscular monitoring accuracy.

Postoperative recurarization after sugammadex administration in two patients who received neoadjuvant chemotherapy: case reports and literature review

BACKGROUND

Preoperative neoadjuvant chemotherapy plays a critical role in multidisciplinary therapy for a variety of malignant tumours. Although oncologists consider myocardial injury to be the most concerning side effect of chemotherapy, unique chemotherapy-mediated skeletal muscular damage has received attention recently.

CLINICAL FEATURES

We report two unusual cases of postoperative delayed respiratory failure following administration of the recommended sugammadex dosage for patients undergoing lengthy operations with deep neuromuscular blockade (NMB) after neoadjuvant chemotherapy. Based on clinical outcomes, especially the comparison of muscle imaging results in patients at different treatment time points, we concluded that NMB recurrence had a possible correlation with neoadjuvant chemotherapy-induced muscular damage.

CONCLUSION

The early identification of neoadjuvant chemotherapeutic side effects on NMB could be instrumental for clinical safety, especially in cases of major surgery requiring deep NMB. Thus, the timing of NMB antagonism and the recommended dosage of sugammadex warrant special consideration in these patients. In addition to neuromuscular monitoring during the operation, a more extended and closer observation period in the postanesthesia care unit is warranted.

Sugammadex Reduced the Incidence of Postoperative Pulmonary Complications in Susceptible Patients Identified by ARISCAT Risk Index: Systematic Review and Meta-analysis

INTRODUCTION

The efficacy of sugammadex on postoperative pulmonary complications (PPCs) in susceptible patients, compared with neostigmine, remains indeterminate. The Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) Group Investigators proposed a risk index for the early identification of susceptible patients, with excellent externally validated discrimination ability. Meta-analytical techniques were applied to evaluate the efficacy of sugammadex on PPCs in patients with ARISCAT-defined risk factors.

METHODS

The study is registered on PROSPERO, number CRD42021261156. We searched PubMed, Scopus, Embase, Cochrane library, GreyNet, and OpenGrey for eligible randomized controlled trials (RCTs) without restricting the language or year of publication.

RESULTS

Twelve RCTs consisting of 1182 patients susceptible to PPCs were included. A robust reduction was observed on the incidence of PPCs in susceptible patients who received sugammadex [RR 0.66; 95% CI (0.54, 0.80), p < 0.01], with a low level of between-study heterogeneity (I2 = 45.98%; H2 = 1.85). Similar protective effects were also proved in avoiding residual neuromuscular block (NMB) [RR 0.25; 95% CI (0.11, 0.56); p < 0.01], atelectasis [RR 0.74; 95% CI (0.59, 0.95); p = 0.02], pneumonia [RR 0.49; 95% CI (0.28, 0.88); p = 0.02], and respiratory failure [RR 0.61; 95% CI (0.39, 0.96); p = 0.03]. No difference was observed regarding adverse events [RR 0.85; 95% CI (0.72, 1.01); p = 0.06].

CONCLUSION

Low to moderate quality of evidence demonstrated the edge of sugammadex over neostigmine for NMB reversal in reducing the likelihood of PPCs and residual NMB in patients with ARISCAT-defined risk factors. Clinicians may reassess the type of reversal agent when treating patients susceptible to PPCs.

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

In this Pro-Con article, we debate the merits of using quantitative neuromuscular blockade monitoring. Consensus guidelines recommend their use to guide the administration of nondepolarizing neuromuscular blockade and reversal agents. A major impediment to this guideline is that until recently, reliable quantitative neuromuscular blockade monitors have not been widely available. Without them, anesthesia providers have been trained with and are adept at using a variety of qualitative neuromuscular blockade monitors otherwise known as peripheral nerve stimulators. Although perhaps less accurate, anesthesia providers find them reliable and easy to use. They have a long track record of using them with the perception that their use leads to effective neuromuscular blockade reversal and minimizes clinically significant adverse events from residual neuromuscular blockade. In the recent past, 2 disruptive developments have called upon anesthesia care providers to reconsider their practice in neuromuscular blockade administration, reversal, and monitoring. These include: (1) commercialization of more reliable quantitative neuromuscular monitors and (2) widespread use of sugammadex, a versatile reversal agent of neuromuscular blockade. Sugammadex appears to be so effective at rapidly and effectively reversing even the deepest of neuromuscular blockades, and it has left anesthesia providers wondering whether quantitative monitoring is indeed necessary or whether conventional, familiar, and less expensive qualitative monitoring will suffice? This Pro-Con debate will contrast anesthesia provider perceptions with evidence surrounding the use of quantitative neuromuscular blockade monitors to explore whether quantitative neuromuscular monitoring (NMM) is just another technology solution looking for a problem or a significant advance in NMM that will improve patient safety and outcomes.

Residual paralysis caused by 50 mg rocuronium after reversal with 4 mg/kg sugammadex: a case report

Background

Rocuronium-induced neuromuscular blockade can be quickly and completely reversed by administration of an optimal dose of sugammadex. Sugammadex antagonizes rocuronium-induced neuromuscular blockade by encapsulating rocuronium. Herein, we report a case of residual neuromuscular paralysis in which the recommended dose of sugammadex (4 mg·kg^− 1) failed to antagonize a rocuronium-induced blockade.

Case presentation

A 71-year-old man (body mass index: 26.7 kg·m^− 2) underwent endoscopic submucosal dissection of early-stage gastric cancer. He had no known factors that may have affected the effects of rocuronium and sugammadex. He received rocuronium (50 mg; 0.7 mg·kg^− 1) for anesthesia induction. No additional rocuronium was administered during the 71-min procedure. Ninety-four minutes after rocuronium administration, neuromuscular monitoring showed 20 twitches in response to post-tetanic count stimulation. The train-of-four (TOF) ratio was not measurable despite sugammadex (280 mg; 4 mg/kg) administration, although four weak twitches in response to TOF stimulation appeared in 3 min. The TOF ratio became detectable following administration of an additional dose of sugammadex (120 mg; 1.7 mg·kg^− 1), and it recovered to 107% 8 min after the second dose. The patient opened his eyes; moved his neck, arms, and limbs; and regained consciousness. The trachea was extubated and the patient was transferred to the ward.

Conclusions

Neuromuscular monitoring should be used if a neuromuscular blockage agent is administered, even if the recommended dose of sugammadex is administered.

What is the Role of Sugammadex in the Emergency Department?

BACKGROUND

Sugammadex is a medication newly available to many emergency physicians. It effectively, and within minutes, reverses neuromuscular blockade in patients who have received rocuronium or vecuronium. The role of sugammadex for the reversal of neuromuscular blockade after rapid sequence intubation in the emergency department (ED) is evolving, and limited emergency medicine-specific literature exists.

OBJECTIVE

This narrative review evaluates the role of sugammadex for the reversal of neuromuscular blockade in the ED.

DISCUSSION

The basic pharmacology, duration of action, adverse effects, and important medication and disease interactions specific to sugammadex are well described. Case reports suggest sugammadex can reverse neuromuscular blockade to facilitate an urgent, neurologic examination by an emergency physician or consultant. Multiple case reports of failure to improve airway patency with the use of sugammadex, even when neuromuscular blockade is completely reversed, and concern for added difficulty of definitive airway management in a patient with spontaneous movement suggest that sugammadex should largely be omitted from failed or difficult airway management strategies. Instead, it is important to focus on the ability to oxygenate and ventilate, including progression to surgical airway or jet ventilation if needed.

CONCLUSION

Sugammadex is an effective, rapid reversal agent for rocuronium and has the potential use to facilitate an urgent neurologic examination shortly after administration of rocuronium. Its routine inclusion in a failed or difficult emergency airway is not supported by available literature.

History of the development of antagonists for neuromuscular blocking agents

Muscle relaxation induced by neuromuscular blocking agents (NMBAs) is necessary for tracheal intubation and immobilization during surgery. Although acetylcholinesterase inhibitors have been successfully used as antagonists for NMBAs, they have their limitations; their effects are transient and ineffective against profound neuromuscular blockade. In the past, alternative antagonists were developed, such as germine and 4-aminopyridine, which are effective for the treatment of diseases causing muscle weakness and could potentially be used as antagonists for NMBAs. Unfortunately, these drugs did not come into practical use due to unwanted side-effects. Sugammadex is an almost ideal antagonist because it rapidly forms a rigid complex with rocuronium and produces less adverse effects. The development of novel NMBAs and antagonists, especially sugammadex, has revolutionized anesthesia practice. Recently, novel short-acting NMBAs, such as gantacurium and CW002 have been developed. Their effects can be reversed by the amino-acid L-cysteine. More recently, calabadions have been developed, which can form complexes with both steroidal and bisbenzyl-isoquinolinium NMBAs, in a similar fashion as sugammadex. Understanding the history of the NMBA antagonist's development is interesting and useful for modern anesthesiologists since it enhances their knowledge about the mechanisms involved in neuromuscular transmission and might lead to the development of ideal NMBA antagonists.

Residual Weakness and Recurarization After Sugammadex Administration in Pediatric Patients: A Case Series

While shown to be safe for administration in pediatric patients, sugammadex has recently been associated with residual weakness or recurarization. We describe 4 additional cases of pediatric patients with residual or recurrent weakness following rocuronium reversal with sugammadex. Two infant patients developed postoperative ventilatory distress, which was possibly related to recurarization after sugammadex reversal. A third patient received sugammadex with apparent waning of clinical effect and subsequently required neostigmine reversal. A fourth patient was observed to have residual weakness, which led to prolonged intubation despite appropriate train-of-four results after reversal with sugammadex.

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.

Sugammadex: Applications in Pediatric Critical Care

Sugammadex is a novel pharmacologic agent, which reverses neuromuscular blockade with a mechanism that differs from acetylcholinesterase inhibitors such as neostigmine. There is a growing body of literature demonstrating its efficacy in pediatric patients of all ages. Prospective trials have demonstrated a more rapid and more complete reversal of rocuronium-induced neuromuscular blockade than the acetylcholinesterase inhibitor, neostigmine. Unlike the acetylcholinesterase inhibitors, sugammadex effectively reverses intense or complete neuromuscular blockade. It may also be effective in situations where reversal of neuromuscular blockade is problematic including patients with neuromyopathic conditions or when acetylcholinesterase inhibitors are contraindicated. This article reviews the physiology of neuromuscular transmission as well as the published literature, regarding the use of sugammadex in pediatric population including the pediatric intensive care unit population. Clinical applications are reviewed, adverse effects are discussed, and dosing algorithms are presented.

Safety of sugammadex for reversal of neuromuscular block

Introduction: Sugammadex is a modified cyclodextrin that is able to reverse neuromuscular block induced by aminosteroidal neuromuscular blocking drugs. Compared to reversal with neostigmine, it reverses neuromuscular block quicker and more predictable and without cholinergic side effects. However, there have been concerns about sugammadex ability to bind other drugs and its effects on QT interval and clotting times. In addition, sugammadex might induce hypersensitivity reactions more frequently than initially anticipated. This review summarizes current evidence with regard to these and other safety aspects of sugammadex. Areas covered: This review provides an overview of the efficacy of sugammadex in various patient populations, evaluates potential interactions with other drugs and discusses adverse effects and reactions that have been reported in the literature. Expert opinion: Sugammadex quickly reverses aminosteroid neuromuscular block with less side effects compared to neostigmine. As such, it has the potential to significantly reduce the incidence of residual neuromuscular block and to improve postoperative pulmonary outcome. Current safety concerns mainly focus on hypersensitivity reactions and cardiac arrhythmias. Although the absolute risk for these events is low, ongoing vigilance and research in this area are needed.

Differences of Recovery from Rocuronium-induced Deep Paralysis in Response to Small Doses of Sugammadex between Elderly and Nonelderly Patients

Editor’s Perspective

What We Already Know about This Topic

What This Article Tells Us That Is New

Background

Complete recovery from rocuronium-induced muscle paralysis with sugammadex is reported to be delayed in elderly patients. The authors tested a hypothesis that recovery from deep neuromuscular block with low-dose sugammadex is slower (primary hypothesis) and incidence of recurarization is higher (secondary hypothesis) in elderly patients than in nonelderly patients.

Methods

In anesthetized elderly (n = 20; 76.9 ± 5.0 yr of age) and nonelderly patients (n = 20; 53.7 ± 12.8 yr of age) under deep paralysis with rocuronium, change of train-of-four ratio per minute (primary outcome variable) was measured with an acceleromyograph neuromuscular monitor during spontaneous recovery from rocuronium-induced muscle paralysis (0.6 mg/kg) and after infusion of low-dose sugammadex (50 µg · kg-1 · min-1). Recurarization was defined as the negative change of train-of-four ratio.

Results

Spontaneous train-of-four ratio recovery rate was significantly slower in the elderly group (median [25th percentile, 75th percentile]: 1.89 [1.22, 2.90] %/min) than in the nonelderly group (3.45 [1.96, 4.25] %/min, P = 0.024). Train-of-four ratio change rate in response to low-dose sugammadex was significantly slower in elderly (0.55 [–0.29, 1.54] %/min) than in the nonelderly group (1.68 [0.73, 3.13] %/min, P = 0.024). Incidence of recurarization was significantly higher in the elderly group than in the nonelderly group (35% vs. 5%, P = 0.044). Multiple linear regression analyses indicate that slower spontaneous train-of-four ratio recovery rate and impaired renal function are two major contributing factors that decrease train-of-four ratio change rate in response to low-dose sugammadex.

Conclusions

Elderly patients are at greater risk for recurarization and residual muscle paralysis when low-dose sugammadex is administered.

Preparing for the unexpected: special considerations and complications after sugammadex administration

Sugammadex, a modified gamma-cyclodextrin, has changed clinical practice of neuromuscular reversal dramatically. With the introduction of this selective relaxant binding agent, rapid and reliable neuromuscular reversal from any depth of block became possible. Sugammadex can reverse neuromuscular blockade without the muscarinic side effects typically associated with the administration of acetylcholinesterase inhibitors. However, what remained unchanged is the incidence of residual neuromuscular blockade. It is known that sugammadex cannot always prevent its occurrence, if appropriate dosing is not chosen based on the level of neuromuscular paralysis prior to administration determined by objective neuromuscular monitoring. Alternatively, excessive doses of sugammadex administered in an attempt to ensure full and sustained reversal may affect the effectiveness of rocuronium in case of immediate reoperation or reintubation. In such emergent scenarios that require onset of rapid and reliable neuromuscular blockade, the summary of product characteristics (package insert) recommends using benzylisoquinolinium neuromuscular blocking agents or a depolarizing agent. However, if rapid intubation is required, succinylcholine has a significant number of side effects, and benzylisoquinolinium agents may not have the rapid onset required. Therefore, prior administration of sugammadex introduces a new set of potential problems that require new solutions. This novel reversal agent thus presents new challenges and anesthesiologists must familiarize themselves with specific issues with its use (e.g., bleeding risk, hypermagnesemia, hypothermia). This review will address sugammadex administration in such special clinical situations.

Development of an algorithm using clinical tests to avoid post-operative residual neuromuscular block

BACKGROUND

Quantitative neuromuscular monitoring is the gold standard to detect postoperative residual curarization (PORC). Many anesthesiologists, however, use insensitive, qualitative neuromuscular monitoring or unreliable, clinical tests. Goal of this multicentre, prospective, double-blinded, assessor controlled study was to develop an algorithm of muscle function tests to identify PORC.

METHODS

After extubation a blinded anesthetist performed eight clinical tests in 165 patients. Test results were correlated to calibrated electromyography train-of-four (TOF) ratio and to a postoperatively applied uncalibrated acceleromyography. A classification and regression tree (CART) was calculated developing the algorithm to identify PORC. This was validated against uncalibrated acceleromyography and tactile judgement of TOF fading in separate 100 patients.

RESULTS

After eliminating three tests with poor correlation, a model with four tests (r = 0.844) and uncalibrated acceleromyography (r = 0.873) were correlated to electromyographical TOF-values without losing quality of prediction. CART analysis showed that three consecutively performed tests (arm lift, head lift and swallowing or eye opening) can predict electromyographical TOF. Prediction coefficients reveal an advantage of the uncalibrated acceleromyography in terms of specificity to identify the EMG measured train-of-four ratio < 0.7 (100% vs. 42.9%) and <0.9 (89.7% vs. 34.5%) compared to the algorithm. However, due to the high sensitivity of the algorithm (100% vs. 94.4%), the risk to overlook an awake patient with a train-of-four ratio < 0.7 was minimal. Tactile judgement of TOF fading showed poorest sensitivity and specifity at train of four ratio < 0.9 (33.7%, 0%) and <0.7 (18.8%, 16.7%).

CONCLUSIONS

Residual neuromuscular blockade can be detected by uncalibrated acceleromyography and if not available by a pathway of four clinical muscle function tests in awake patients. The algorithm has a discriminative power comparable to uncalibrated AMG within TOF-values >0.7 and <0.3.

TRIAL REGISTRATION

Clinical Trials.gov (principal investigator's name: CU, and identifier: NCT03219138) on July 8, 2017.

Half dose sugammadex combined with neostigmine is non-inferior to full dose sugammadex for reversal of rocuronium-induced deep neuromuscular blockade: a cost-saving strategy

BACKGROUND

Sugammadex reverses the effect of rocuronium more rapidly and effectively than neostigmine, at all levels of neuromuscular blockade (NMB). However, its cost is prohibitive. The combination of half dose sugammadex with neostigmine would be non-inferior to full dose sugammadex for the reversal of deep NMB. This approach would reduce the cost of sugammadex while preserving its efficacy.

METHODS

Patients were randomly allocated to receive sugammadex 4 mg/kg (Group S) or sugammadex 2 mg/kg with neostigmine 50 μg/kg and glycopyrrolate 10 μg/kg (Group NS) for reversal of rocuronium deep NMB. The primary outcome was the percentage of patients who recovered to 90% Train of Four (TOF) ratio within 5 min. The non-inferiority margin was set at 10%.

RESULTS

Twenty eight patients were enrolled in each group. The number of patients who reached 90% TOF ratio within 5 min was 27 out of 28 (96%) in group S versus 25 out of 28 (89%) in group NS by intention-to-treat (difference: 7%, 95% CI of the difference: -9% to 24%). The number of patients who reached 90% TOF ratio within 5 min was 26 out of 26 (100%) in group S versus 23 out of 25 (92%) in group NS by per-protocol (difference: 8%, 95% CI of the difference: -6% to 25%).

CONCLUSIONS

Sugammadex 2 mg/kg with neostigmine 50 μg/kg was at worst 9% and 6% less effective than sugammadex 4 mg/kg by intention-to-treat and by per-protocol analysis respectively. Hence, the combination is non-inferior to the recommended dose of sugammadex.

TRIAL REGISTRATION

Clinicaltrials.gov NCT 02375217 , registered on February 11, 2015.

A comparison of sugammadex and neostigmine for reversal of rocuronium-induced neuromuscular blockade in children

BACKGROUND

Sugammadex is designed to be a reversal agent for steroidal muscle relaxants. The current trial was aimed to compare between sugammadex and neostigmine concerning the recovery time from neuromuscular blockade. We hypothesised that sugammadex might have shorter recovery time than neostigmine.

METHODS

Sixty paediatric patients aged 2-10 years scheduled for lower abdominal surgeries were randomly assigned into two equal groups to receive 4 mg/kg sugammadex (Group S) or 0.35 mg/kg neostigmine and 0.02 mg/kg atropine (Group N) as a reversal agent for rocuronium at the end of surgery. Primary outcome was the recovery time [time from starting of sugammadex or neostigmine till reaching train of four (TOF) ratio> 0.9] whereas secondary outcomes included number of patients who needed another dose of sugammadex or neostigmine to reach TOF ratio> 0.9, extubation time (time from stoppage of anaesthetic inhalation until the patient fulfilled criteria for safe extubation, post-anaesthesia care unit (PACU) discharge time and post-operative adverse effects.

RESULTS

The mean recovery and extubation times were significantly shorter (P = 0.002 and 0.005) in Group S compared with Group N (2.5 and 2.0 min vs. 12.6 min and 4.3 min respectively). In the Group N, eight patients needed another reversal dose compared with one patient in Group S (P = 0.035). PACU discharge time showed no significant difference between both groups. Incidence of nausea, vomiting, tachycardia, and dry mouth were significantly higher in Group N.

CONCLUSION

Sugammadex administration in children resulted in faster recovery and extubation times and lower incidence of adverse events compared with neostigmine.

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.

Observational study on patterns of neuromuscular blockade reversal

BACKGROUND

Using electronic health record data, we hypothesized that larger reversal doses are used for patients with deeper levels of neuromuscular blockade (NMB) as evidenced by the last recorded TOF measurement. We also examined if dosing regimens reflect current practice guidelines of using ideal body weight (IBW) for NMB agents and total body weight (TBW) for neostigmine.

METHODS

This is a retrospective observational study of adult, ASA 1-4 patients who underwent general anaesthesia and received non-depolarizing NMB agents between 01/01/2004 and 12/31/2013. For the primary outcome, percentages of cases receiving neostigmine and median doses administered for each subjective train-of-four (TOF) category were calculated. Secondary analyses evaluated associations between NMB dosing and neostigmine administration based on Body Mass Index (BMI) categories.

RESULTS

A total of 135,633 cases met inclusion criteria for the study. There was no clinically significant difference in median neostigmine dosing based on last TOF count prior to reversal administration: 37.5 mcg/kg for TOF of 4/4 vs. 37.9 mcg/kg for TOF of 0/4 for the total neostigmine dose. Significantly higher number of patients with lower TOF counts received additional neostigmine administration: 5.7 % for 0/4 vs. 1.5 % for 4/4 TOF counts. The median times to extubation following neostigmine administration were clinically similar across TOF count categories. The median doses for neostigmine based on TBW decreased with higher BMI categories and were significantly different between the lowest and highest categories: 42.8 mcg/kg vs 30.8 mcg/kg for total doses (p < .0001) respectively. The percentages of cases requiring reversal in addition to the initial dose increased with increasing BMI categories and were 2.1 % for BMI < 18 vs. 3.3 % for BMI ≥ 40. The total median dose of NMB agents in ED95 equivalents per IBW increased from 2.9 in the Underweight category to 4.2 in the Class III Obese category. The majority of patients in the pancuronium subgroup received very low ED95 equivalent dose of 0.1 and did not require reversal. Patients receiving cisatracurium were given significantly higher median ED95 equivalent dose of 5.6 vs 2.8-3.9 compared to other intermediate acting NMB agents, while receiving clinically similar doses of neostigmine.

CONCLUSIONS

Neither neostigmine dosing nor times to extubation were affected by the depth of the neuromuscular blockade prior to reversal. The need for additional reversal, or rescue, correlated strongly with the depth of NMB. There was significant variability in neostigmine dosing across the BMI categories. Underweight patients received relatively lower NMB doses while simultaneously receiving relatively higher reversal doses, and the opposite was true for patients with BMI >40.

Postoperative Respiratory Failure in a Patient with Undiagnosed Myastenia Gravis

Myasthenia gravis (MG) is an autoimmune disease caused by the development of antibodies against the nicotinic acetylcholine receptor. There is hypersensitivity against non-depolarizing muscle relaxants in these patients. Sugammadex eliminates the effects of steroid non-depolarizing muscle relaxants, such as rocuronium and vecuronium, by selectively encapsulating their molecules. In this case report, we present a case of recurarization and respiratory failure after the use of sugammadex and rocuronium in a patient with preoperatively undiagnosed myasthenia gravis.

Reversing neuromuscular blockade: inhibitors of the acetylcholinesterase versus the encapsulating agents sugammadex and calabadion

INTRODUCTION

Acetylcholinesterase inhibitors (neostigmine, edrophonium) and encapsulating agents (sugammadex and calabadion) can be used to reverse residual neuromuscular blockade (NMB).

AREAS COVERED

This review provides information about efficacy, effectiveness, and side effects of drugs (acetylcholinesterase inhibitors and encapsulating agents) used to reverse neuromuscular blocking agents (NMBAs).

EXPERT OPINION

The therapeutic range of acetylcholinesterase-inhibitors is narrow and effectiveness studies demonstrate clinicians don't use these unspecific reversal agents effectively to increase postoperative respiratory safety. The encapsulating drugs sugammadex and calabadion reverse all levels of NMB, and complete recovery of muscle strength can be achieved almost immediately after administration. For this reason encapsulating agents can be used as a solution for "cannot intubate cannot ventilate"- situations. Poor binding selectivity of encapsulating agents carries the risk of displacement of the NMBA by a competitively binding drug, which may lead to recurarization. In order to avoid side-effects, related to unspecific binding of endogenous proteins and drugs administered perioperatively it is prudent to titrate the dose of reversal agents to the minimal effective dose, depending on the depth of neuromuscular transmission block identified by neuromuscular transmission monitoring. Calabadions provide a diversified (increased binding selectivity) and expanded (reversal of benzylisoquinolines) spectrum of possible indications.

Reversal agents in anaesthesia and critical care

Despite the advent of short and ultra-short acting drugs, an in-depth knowledge of the reversal agents used is a necessity for any anaesthesiologist. Reversal agents are defined as any drug used to reverse the effects of anaesthetics, narcotics or potentially toxic agents. The controversy on the routine reversal of neuromuscular blockade still exists. The advent of newer reversal agents like sugammadex have made the use of steroidal neuromuscular blockers like rocuronium feasible in rapid sequence induction situations. We made a review of the older reversal agents and those still under investigation for drugs that are regularly used in our anaesthesia practice.

Reversal of neuromuscular blockade by sugammadex in laparoscopic bariatric surgery: In support of dose reduction

INTRODUCTION

Sugammadex is the first molecule able to antagonize steroidal muscle relaxants with few adverse effects. Doses are adjusted to body weight and the level of neuromuscular blockade. Sleeve gastrectomy is becoming a very popular form of bariatric surgery. It requires deep muscle relaxation followed by complete and rapid reversal to decrease postoperative and especially post-anaesthetic morbidity. Sugammadex is therefore particularly indicated in this setting. The objective of this study was to evaluate the deep neuromuscular blockade reversal time after administration of various doses of sugammadex (based on real weight or at lower doses). Secondary endpoints were the interval between the sugammadex injection and extubation and transfer from the operating room to the recovery room. We then investigated any complications observed in the recovery room.

MATERIALS AND METHODS

This pilot, prospective, observational, clinical practice evaluation study was conducted in the Amiens University Hospital. Neuromuscular blockade was induced by rocuronium. At the end of the operation, deep neuromuscular blockade was reversed by sugammadex at the dose of 4mg/kg.

RESULTS

Sixty-four patients were included: 31 patients received sugammadex at a dosage based on their real weight (RW) and 33 patients received a lower dose (based on ideal weight [IW]). For identical rocuronium doses calculated based on IBW, sugammadex doses were significantly lower in the IW group: 349 (± 65) mg versus 508 (± 75) mg (P<0.0001). Despite this dose reduction, neuromuscular blockade reversal took 115 (± 69) s in the IW group versus 87 (± 40) s in the RW group, but with no significant difference between the two groups (P=0.08). The intervals between injection of sugammadex and extubation (P=0.07) and transfer from the operating room to the recovery room (P=0.68) were also non-significantly longer in the IW group. The mean dose of sugammadex used by anaesthetists in the IW group was 4mg/kg of ideal weight increased by 35% to 50% (n=20; 351±34mg). No sugammadex adverse effects and no residual neuromuscular blockades were observed. Postoperative nausea and vomiting (PONV) was observed in 19.4% of patients in the real weight group versus 27.3% in the ideal weight group (P=NS).

CONCLUSION

Reversal of deep neuromuscular blockades by sugammadex in obese subjects can be performed at doses of 4mg/kg of ideal weight plus 35-50% with no clinical consequences and no accentuation of adverse effects.

Effects of sugammadex on incidence of postoperative residual neuromuscular blockade: a randomized, controlled study

BACKGROUND

This study aimed to investigate whether reversal of rocuronium-induced neuromuscular blockade with sugammadex reduced the incidence of residual blockade and facilitated operating room discharge readiness.

METHODS

Adult patients undergoing abdominal surgery received rocuronium, followed by randomized allocation to sugammadex (2 or 4 mg kg(-1)) or usual care (neostigmine/glycopyrrolate, dosing per usual care practice) for reversal of neuromuscular blockade. Timing of reversal agent administration was based on the providers' clinical judgement. Primary endpoint was the presence of residual neuromuscular blockade at PACU admission, defined as a train-of-four (TOF) ratio <0.9, using TOF-Watch® SX. Key secondary endpoint was time between reversal agent administration and operating room discharge-readiness; analysed with analysis of covariance.

RESULTS

Of 154 patients randomized, 150 had a TOF value measured at PACU entry. Zero out of 74 sugammadex patients and 33 out of 76 (43.4%) usual care patients had TOF-Watch SX-assessed residual neuromuscular blockade at PACU admission (odds ratio 0.0, 95% CI [0-0.06], P<0.0001). Of these 33 usual care patients, 2 also had clinical evidence of partial paralysis. Time between reversal agent administration and operating room discharge-readiness was shorter for sugammadex vs usual care (14.7 vs. 18.6 min respectively; P=0.02).

CONCLUSIONS

After abdominal surgery, sugammadex reversal eliminated residual neuromuscular blockade in the PACU, and shortened the time from start of study medication administration to the time the patient was ready for discharge from the operating room.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov:NCT01479764.

Postoperative respiratory outcomes in laparoscopic bariatric surgery: comparison of a prospective group of patients whose neuromuscular blockade was reverted with sugammadex and a historical one reverted with neostigmine

PURPOSE

Bariatric surgery patients are at high risk of perioperative respiratory adverse events. We hypothesized that the use of sugammadex to reverse neuromuscular blockade could improve postoperative respiratory outcomes.

METHODS

Prospective observational series of consecutive patients scheduled for laparoscopic bariatric surgery in whom neuromuscular blockade was reverted with sugammadex were compared with a historical matched cohort of patients reverted with neostigmines. The necessity of postoperative mechanical ventilation or pathological changes in postoperative chest X-ray were two of the comparisons done.

RESULTS

We enrolled 160 patients in each group (Sugammadex - SG and Historical - HG). Two patients (mean, CI 95%), (1.25, 0.34-4.4) in the SG and five patients in the HG (mean, CI 95%), (3.13, 1.34-7.11) required mechanical ventilation immediately after surgery (p=0.38, chi-square test). Significantly less chest X-ray postoperative changes were observed in the SG: 11 patients (6.9%) versus 26 patients (16.3%) in the HG (Odds ratio OR, CI 95%) (0.36, 0.18-0.8).

CONCLUSION

Requirement of mechanical ventilation is not associated to the reversal agent employed. Less pathological postoperative chest X-ray changes were found in the group of patients whose neuromuscular blockade was reverted with sugammadex.

Sugammadex as a reversal agent for neuromuscular block: an evidence-based review

Sugammadex is the first clinical representative of a new class of drugs called selective relaxant binding agents. It has revolutionized the way anesthesiologists think about drug reversal. Sugammadex selectively binds rocuronium or vecuronium, thereby reversing their neuromuscular blocking action. Due to its 1:1 binding of rocuronium or vecuronium, it is able to reverse any depth of neuromuscular block. So far, it has been approved for use in adult patients and for pediatric patients over 2 years. Since its approval in Europe, Japan, and Australia, further insight on its use in special patient populations and specific diseases have become available. Due to its pharmacodynamic profile, sugammadex, in combination with rocuronium, may have the potential to displace succinylcholine as the "gold standard" muscle relaxant for rapid sequence induction. The use of rocuronium or vecuronium, with the potential of reverse of their action with sugammadex, seems to be safe in patients with impaired neuromuscular transmission, ie, neuromuscular diseases, including myasthenia gravis. Data from long-term use of sugammadex is not yet available. Evidence suggesting an economic advantage of using sugammadex and justifying its relatively high cost for an anesthesia-related drug, is missing.

Anesthetic Pharmacology and the Morbidly Obese Patient

Anesthesiologists are increasingly being faced with treating obese patients. Physiologic and anthropometric associated with obesity-most notably increases in cardiac output, changes in tissue perfusion and increases in total body weight (TBW), lean body weight (LBW), and fat mass affect the pharmacokinetics (PK) of anesthetic agents. In addition, redundancy of airway tissue, obstructive and central sleep apnea and CO2 retention affect the pharmacodynamics (PD) of anesthetics and narrow the therapeutic window of numerous anesthetic drugs. Safe and effective pharmacologic management of the obese patient requires a thorough understanding of how obesity affects the PK and PD of anesthetics.