Sugammadex rapidly reverses moderate rocuronium- or vecuronium-induced neuromuscular block during sevoflurane anaesthesia: a dose-response relationship

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.

Primary Lateral Sclerosis: Can Rocuronium Be an Option?

Primary lateral sclerosis (PLS) is a neurodegenerative motor neuron disorder that is characterized by corticospinal and corticobulbar dysfunction. In this disease, muscle relaxants in general anesthesia should be used with extreme caution. A 67-year-old woman with a history of PLS was scheduled for laparoscopic gastrostomy due to long-term dysphagia. In the preoperative assessment, she presented a tetrapyramidal syndrome with generalized muscle weakness. A priming dose of 5 mg of rocuronium was administered and the train-of-four (TOF) ratio (T4/T1) after 60 seconds was 70% so induction was followed with fentanyl, propofol, and additional 40 mg of rocuronium. After 90 seconds when T1 was lost, the patient was intubated. During surgery, the TOF ratio increased progressively until 65%, 22 minutes after a final bolus of 10 mg of rocuronium. Prior to emergence, 150 mg of sugammadex was given and neuromuscular block reversal was evidenced with a TOF ratio > 90%. As it was decided to perform the surgery laparoscopically, general anesthesia with a neuromuscular blockade was necessary. Since it is reported that patients with motor neuron diseases show an increased sensibility to non-depolarizing muscle relaxants (NDMR), these agents should be used cautiously. Adversely to what studies document, no augmented responsiveness was shown in TOF monitoring, so the standard dose of 0.6 mg/kg of rocuronium was safely given. A final bolus of NDMR was administered after 54 minutes, demonstrating a similar pharmacokinetics profile in terms of duration of action as reported in several studies (45-70 minutes). In addition, a full and rapid neuromuscular blockade recovery with 2 mg/kg of sugammadex was seen, as previously demonstrated in a case series.

2023 American Society of Anesthesiologists Practice Guidelines for Monitoring and Antagonism of Neuromuscular Blockade: A Report by the American Society of Anesthesiologists Task Force on Neuromuscular Blockade

These practice guidelines provide evidence-based recommendations on the management of neuromuscular monitoring and antagonism of neuromuscular blocking agents during and after general anesthesia. The guidance focuses primarily on the type and site of monitoring and the process of antagonizing neuromuscular blockade to reduce residual neuromuscular blockade.

Retrospective observational study of the effects of residual neuromuscular blockade and sugammadex on motor-evoked potential monitoring during spine surgery in Japan

Given neuromuscular blockade (NMB) can affect the amplitude and detection success rate of motor-evoked potentials (MEP), sugammadex may be administered intraoperatively. We evaluated the factors affecting the degree of residual NMB (i.e., the train-of-four [TOF] ratio) and the relationship between TOF ratio and MEP detection success rate in Japanese patients undergoing spine surgery. This single-center retrospective observational study included adults who underwent spine surgery under propofol/remifentanil anesthesia, received rocuronium for intubation, and underwent myogenic MEP monitoring after transcranial stimulation. TOF ratios were assessed using electromyography. Sugammadex was administered after finishing the MEP setting and the TOF ratio was ≤0.7. To identify factors affecting the TOF ratio, TOF ratio and MEP detection success rate were simultaneously measured after finishing the MEP setting; to compare the time from intubation to the start of MEP monitoring after NMB recovery between sugammadex and spontaneous recovery groups, multivariable analyses were performed. Of 373 cases analyzed, sugammadex was administered to 221 (59.2%) cases. Age, blood pressure, hepatic impairment, and rocuronium dose were the main factors affecting the TOF ratio. Patients with higher TOF ratios (≥0.75) had higher MEP detection success rates. The time from intubation to the start of MEP monitoring after NMB recovery was significantly shorter in patients administered sugammadex versus patients without sugammadex (P < .0001). The MEP detection success rate was higher in patients with a TOF ratio of ≥0.75. Sugammadex shortened the time from intubation to the start of MEP monitoring after NMB recovery.

Required dose of sugammadex or neostigmine for reversal of vecuronium-induced shallow residual neuromuscular block at a train-of-four ratio of 0.3

Residual shallow neuromuscular block (NMB) is potentially harmful and contributes to critical respiratory events. Evidence for the optimal dose of sugammadex required to reverse vecuronium‐induced shallow NMB is scarce. The aims of the present study were to find suitable doses of sugammadex and neostigmine to reverse a residual vecuronium‐induced NMB from a time of flight (TOF) ratio of 0.3–0.9 and evaluate their safety and efficacy. In total, 121 patients aged 18–65 years were randomly assigned to 11 groups to receive placebo, sugammadex (doses of 0.125, 0.25, 0.5, 1.0, or 2.0 mg/kg), or neostigmine (doses of 10, 25, 40, 55, or 70 μg/kg). The reversal time of sugammadex and neostigmine to antagonize a vecuronium‐induced shallow residual NMB (i.e., TOF ratio of 0.3) and related adverse reactions were recorded. Several statistical models were tested to find an appropriate statistical model to explore the suitable doses of sugammadex and neostigmine required to reverse a residual vecuronium‐induced NMB. Based on a monoexponential model with the response variable on a logarithmic scale, sugammadex 0.56 mg/kg may be sufficient to reverse vecuronium‐induced shallow residual NMB at a TOF ratio of 0.3 under anesthesia maintained with propofol. Neostigmine may not provide prompt and satisfactory antagonism as sugammadex, even in shallow NMB.

Carboxymethyl-γ-cyclodextrin, a novel selective relaxant binding agent for the reversal of neuromuscular block induced by aminosteroid neuromuscular blockers: an ex vivo laboratory study

BACKGROUND

Residual neuromuscular block at the end of surgery may compromise the patient's safety. The risk of airway complications can be minimized through monitoring of neuromuscular function and reversal of neuromuscular block if needed. Effective reversal can be achieved with selective relaxant binding agents, however, sugammadex is the only clinically approved drug in this group. We investigated the concentration-response properties of a novel selective relaxant binding agent, carboxymethyl-γ-cyclodextrin for the reversal of neuromuscular block. We evaluated the hypothesis that it is equally potent for reversing neuromuscular block as sugammadex.

METHODS

Phrenic nerve - hemidiaphragm tissue preparations were isolated from male Wistar rats and suspended in a tissue holder allowing electrical stimulation of the nerve and monitoring of muscle contraction force. Concentration-response relationships were constructed for the neuromuscular blocking agents rocuronium, pipecuronium, and vecuronium. The half-effective concentrations of sugammadex and carboxymethyl-γ-cyclodextrin for reversal of neuromuscular block were determined.

RESULTS

The half effective concentrations (95% confidence interval, CI) were 7.50 (6.93-8.12) μM for rocuronium, 1.38 (1.33-1.42) μM for pipecuronium, and 3.69 (3.59-3.80) μM for vecuronium. The half effective concentrations (95% CI) of carboxymethyl-γ-cyclodextrin and sugammadex were 35.89 (32.67-39.41) μM and 3.67 (3.43-3.92) μM, respectively, for the reversal of rocuronium-induced block; 10.14 (9.61-10.70) μM and 0.67 (0.62-0.74) μM, respectively, for the reversal of pipecuronium-induced block; and 376.1 (341.9-413.8) μM and 1.45 (1.35-1.56) μM, respectively, for the reversal of vecuronium-induced block.

CONCLUSIONS

Carboxymethyl-γ-cyclodextrin is an effective, but less potent agent for reversal of neuromuscular block than sugammadex.

Comparison of postoperative pulmonary complications between sugammadex and neostigmine in lung cancer patients undergoing video-assisted thoracoscopic lobectomy: a prospective double-blinded randomized trial

BACKGROUND

Reversal of neuromuscular blockade (NMB) at the end of surgery is important for reducing postoperative residual NMB; this is associated with an increased risk of postoperative pulmonary complications (PPCs). Moreover, PPCs are associated with poor prognosis after video-assisted thoracoscopic surgery (VATS) for lobectomy. We compared the effects of two reversal agents, sugammadex and neostigmine, on the incidence of PPCs and duration of hospital stay in patients undergoing VATS lobectomy.

METHODS

After VATS lobectomy was completed under neuromuscular monitoring, the sugammadex group (n = 46) received sugammadex 2 mg/kg, while the neostigmine group (n = 47) received neostigmine 0.05 mg/kg with atropine 0.02 mg/kg after at least the third twitch in response to the train of four stimulation. The primary outcome was incidence of PPCs. The secondary outcomes were duration of hospital stay and intensive care unit (ICU) admission.

RESULTS

There was no significant difference in the incidence of PPCs for both the sugammadex and neostigmine groups (32.6% and 40.4%, respectively; risk difference = 0.08; 95% confidence interval = [-0.12, 0.27]; P = 0.434). The lengths of hospital (P = 0.431) and ICU (P = 0.964) stays were not significantly different between the two groups.

CONCLUSIONS

The clinical use of sugammadex and neostigmine in NMB reversal for patients undergoing VATS lobectomy was not significantly different in the incidence of PPCs and duration of hospital and ICU stay.

Half-dose sugammadex with neostigmine versus full-dose sugammadex for reversal of rocuronium in laparoscopic bariatric surgery

Background

Sugammadex reverses rocuronium more effective than neostigmine during deeper neuromuscular blockade levels. Relying upon the high cost of sugammadex we hypothesized that combined neostigmine with half-dose sugammadex (1.2 mg/kg) would be as effective as the full dose (2.4 mg/kg IBW) in reversing rocuronium-induced deep neuromuscular block in obese patients. A multimodal approach would be an effective cost saving strategy, while preserving the advantages of this novel agent.

Patient and methods

A prospective randomized study done on 50 morbid obese patients undergoing elective laparoscopic sleeve gastrectomy operation. Patients were allocated into two groups each of 25. Group NS received sugammadex 1.2 mg/kg and neostigmine 50 μg/kg with atropine 20 μg/kg. Group S received sugammadex 2.4 mg/kg and 10 mL of normal saline.

Primary outcome

Interval between administration of reversal and reaching TOF of 90%.

Secondary outcomes

Total dose of rocuronium (mg), duration between last dose rocuronium and reverse, number of patients reached TOF of 90% within 5 min, duration between IV reversal and extubation, and the number of patients with residual neuromuscular blockade.

Results

Number of patients who reached TOF 90% within 5 min, the interval between reversal and 90% TOF, the interval between reversal and extubation were comparable between the study groups.

Conclusion

As regards neuromuscular blocker reversal in obese patients, the neostigmine 50 μg/kg plus sugammadex half dose (1.2 mg/kg) is as effective as full-dose sugammadex (2.4 mg/kg) alone.

Trial registration

Institutional Research Board: (IRB code number): MS/17.12.195 on 16 January 2018.

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

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

Precision Neuromuscular Block Management for Neural Monitoring During Thyroid Surgery

INTRODUCTION

Titration of neuromuscular block (NMB) plays a key role in intraoperative recurrent laryngeal nerve monitoring during thyroid surgery. The combination of neuromuscular blocking agent and timely partial reversal of NMB was investigated in both animal experiments and clinical neuro-monitored thyroidectomy.

METHODS

In animal experiments, 8 piglets received sugammadex to assess the laryngeal EMG recovery after rocuronium-induced NMB. In clinical monitored thyroidectomy, 40 patients each were allocated to conventional group and sugammadex group. Conventional group received rocuronium 0.3 mg/kg at anesthesia induction, while sugammadex group received partial NMB recovery protocol- 0.6 mg/kg of rocuronium at anesthesia induction and 0.5 mg/kg of sugammadex. Main outcome was assessed by first (V1) and final (V2) EMG signal induced by vagal stimulation.

RESULTS

In the porcine model, 50% recovery of laryngeal EMG amplitude was achieved at 16.8 ± 1.9 and 6 ± 2.7 minutes respectively after 0.5 and 1 mg/kg of sugammadex (p < 0.01). In monitored thyroidectomy, EMG amplitudes at V1 in group S and group C were 1214 ± 623 and 915 ± 476 μV, respectively (p = 0.02). Positive and adequately high EMG amplitudes were observed at the early surgical stage for all patients. Sugammadex groups were superior to conventional group in EMG tube placement (p < 0.001).

CONCLUSION

Both porcine model and clinical application showed that precise NMB management by low-dose sugammadex was effective for intraoperative neural monitoring (IONM). The regimen ensured optimal conditions for tracheal intubation and timely neuromuscular function restoration for high-quality EMG signal.

Potency estimation of sugammadex for the reversal of moderate rocuronium-induced neuromuscular block: a non-randomized dose-response study

PURPOSE

There is no report investigating the precise potency of sugammadex for antagonizing various intensities of rocuronium-induced neuromuscular block. The aim of this study was to evaluate the ED₉₅ of reversibility of sugammadex and reveal the safety factor of 2 mg/kg of sugammadex for moderate rocuronium-induced neuromuscular block.

METHODS

Fifteen patients were enrolled in this study. After induction of anesthesia, we recorded the adductor pollicis muscle response to ulnar nerve stimulation using acceleromyography. All patients received 0.6 mg/kg rocuronium. When the first twitch (T1) of the train-of-four (TOF) response reappeared, rocuronium infusion was commenced to maintain T1 at 10% of the control. After the surgery was completed and infusion of rocuronium was stopped, patients were given sugammadex by a cumulative dose technique. The effective doses of sugammadex that led to recovery of the amplitude of T1 and the TOF ratio by 95% (ED₉₅) were calculated from the regression lines of least-squares regression analysis.

RESULTS

The mean ED₉₅ of sugammadex for recovery of T1 and the TOF ratio from rocuronium-induced moderate neuromuscular block was 1.34 (0.24) and 1.14 (0.24) mg/kg, respectively.

CONCLUSIONS

The ED₉₅ of sugammadex for the recovery of T1 was significantly greater than that for the TOF ratio. However, a sugammadex dose of 2 mg/kg is equivalent to about 1.5 times the ED₉₅ of sugammadex for reversal of moderate rocuronium-induced block, indicating its safety margin.

Neuromuscular blockade management for intraoperative neural monitoring

This article reviews the literature on development of neuromuscular blockade management in thyroid surgery with intraoperative neural monitoring (IONM) in the past decade. Neuromuscular blockade management includes the choice of neuromuscular blocking agents (NMBAs) and reversal of neuromuscular blockade by sugammadex. A series of animal study and clinical trials showed NMBAs effect on IONM in thyroid surgery. We summarized five NMBA regimens for IONM: (a) relaxant-free regimen, (b) depolarizing NMBA-succinylcholine, (c) titration of nondepolarizing NMBA, and (d) rocuronium combined with sugammadex. The proper management of neuromuscular blockade during IONM has greatly developed over the past decade. The misuse of NMBAs is associated with false IONM interpretations to surgeons. A detailed understanding of NMBAs and neuromuscular blockade management by sugammadex may optimize IONM quality in patients receiving monitored thyroid surgery.

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

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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.

Use of Sugammadex in Patients With Obesity: A Pooled Analysis

A growing proportion of patients undergoing surgical procedures are obese, providing anesthesiologists with numerous challenges for patient management. The current pooled analysis evaluated recovery times following sugammadex reversal of neuromuscular blockade by body mass index (BMI) in general, and in particular, in patients with BMIs ≥30 kg/m (defined as obese) and <30 kg/m (defined as non-obese). Data were pooled from 27 trials evaluating recommended sugammadex doses for reversal of moderate [reappearance of the second twitch of the train-of-four (TOF); sugammadex 2 mg/kg] or deep (1-2 post-tetanic counts or 15 minutes after rocuronium; sugammadex 4 mg/kg) rocuronium- or vecuronium-induced neuromuscular blockade. All doses of sugammadex were administered based on actual body weight. The recovery time from sugammadex administration to a TOF ratio ≥0.9 was the primary efficacy variable in all individual studies and in the pooled analysis. This analysis comprised a total of 1418 adult patients treated with sugammadex; 267 (18.8%) of these patients had a BMI ≥30 kg/m. The average time to recovery of the TOF ratio to 0.9 was 1.9 minutes for rocuronium-induced blockade and 3.0 minutes for vecuronium-induced blockade. No clinically relevant correlation was observed between BMI and recovery time. The recommended sugammadex doses based on actual body weight provide rapid recovery from neuromuscular blockade in both obese and non-obese patients; no dose adjustments are required in the obese patient.

Reversal of Vecuronium-induced Neuromuscular Blockade with Low-dose Sugammadex at Train-of-four Count of Four

Background

Rocuronium-induced neuromuscular block that spontaneously recovered to a train-of-four count of four can be reversed with sugammadex 0.5 or 1.0 mg/kg. We investigated whether these doses of sugammadex can also reverse vecuronium at a similar level of block.

Methods

Sixty-five patients were randomly assigned, and 64 were analyzed in this controlled, superiority study. Participants received general anesthesia with propofol, sevoflurane, fentanyl, and vecuronium. Measurement of neuromuscular function was performed with acceleromyography (TOF-Watch-SX, Organon Teknika B.V., The Netherlands ). Once the block recovered spontaneously to four twitches in response to train-of-four stimulation, patients were randomly assigned to receive sugammadex 0.5, 1.0, or 2.0 mg/kg; neostigmine 0.05 mg/kg; or placebo. Time from study drug injection to normalized train-of-four ratio 0.9 and the incidence of incomplete reversal within 30 min were the primary outcome variables. Secondary outcome was the incidence of reparalysis (normalized train-of-four ratio less than 0.9).

Results

Sugammadex, in doses of 1.0 and 2.0 mg/kg, reversed a threshold train-of-four count of four to normalized train-of-four ratio of 0.9 or higher in all patients in 4.4 ± 2.3 min (mean ± SD) and 2.6 ± 1.6 min, respectively. Sugammadex 0.5 mg/kg reversed the block in 6.8 ± 4.1 min in 70% of patients (P &lt; 0.0001 vs. 1.0 and 2.0 mg/kg), whereas neostigmine produced reversal in 11.3 ± 9.7 min in 77% of patients (P &gt; 0.05 vs. sugammadex 0.5 mg/kg). The overall frequency of reparalysis was 18.7%, but this incidence varied from group to group.

Conclusions

Sugammadex 1.0 mg/kg, unlike 0.5 mg/kg, properly reversed a threshold train-of-four count of four vecuronium-induced block but did not prevent reparalysis.

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.

Dexamethasone does not diminish sugammadex reversal of neuromuscular block - clinical study in surgical patients undergoing general anesthesia

Background

Sugammadex reverses neuromuscular block (NMB) through binding aminosteroid neuromuscular blocking agents. Although sugammadex appears to be highly selective, it can interact with other drugs, like corticosteroids. A prospective single-blinded randomized clinical trial was designed to explore the significance of interactions between dexamethasone and sugammadex.

Methods

Sixty-five patients who were anesthetized for elective abdominal or urological surgery were included. NMB was assessed using train-of-four stimulation (TOF), with rocuronium used to maintain the desired NMB depth. NMB reversal at the end of anaesthesia was achieved using sugammadex. According to their received antiemetics, the patients were randomized to either the granisetron or dexamethasone group. Blood samples were taken before and after NMB reversal, for plasma dexamethasone and rocuronium determination. Primary endpoint was time from sugammadex administration to NMB reversal. Secondary endpoints included the ratios of the dexamethasone and rocuronium concentrations after NMB reversal versus before sugammadex administration.

Results

There were no differences for time to NMB reversal between the control (mean 121 ± 61 s) and the dexamethasone group (mean 125 ± 57 s; P = 0.760). Time to NMB reversal to a TOF ratio ≥0.9 was significantly longer in patients with lower TOF prior to sugammadex administration (Beta = −0.268; P = 0.038). The ratio between the rocuronium concentrations after NMB reversal versus before sugammadex administration was significantly affected by sugammadex dose (Beta = −0.375; P = 0.004), as was rocuronium dose per hour of operation (Beta = −0.366; p = 0.007), while it was not affected by NMB depth before administration of sugammadex (Beta = −0.089; p = 0.483) and dexamethasone (Beta = −0.186; p = 0.131). There was significant drop in plasma dexamethasone after sugammadex administration and NMB reversal (p < 0.001).

Conclusions

Administration of dexamethasone to anesthetized patients did not delay NMB reversal by sugammadex.

Trial registration

The trial was retrospectively registered with The Australian New Zealand Clinical Trials Registry (ANZCTR) on February 28th 2012 (enrollment of the first patient on February 2nd 2012) and was given a trial ID number ACTRN12612000245897 and universal trial number U1111-1128-5104.

Sugammadex: A Comprehensive Review of the Published Human Science, Including Renal Studies

Although neuromuscular block (NMB) allows immobility for airway management and surgical exposure, termination of its effect is limited by and associated with side effects of acetylcholinesterase inhibitors. Sugammadex is a selective relaxant binding agent that has been shown to reverse deep NMB, even when administered 3 minutes following a 1.2 mg/kg dose of rocuronium. This novel drug is a modified gamma cyclodextrin, that through encapsulation process terminates the effects of rocuronium and vecuronium (aminosteroid muscle relaxants), and enables the anesthesiologists rapidly to reverse profound NMB induced by rocuronium or vecuronium, in a "can't ventilate, can't intubate" crisis. In this review, data from published phase 1, 2, and 3 clinical trials are reviewed and presented. In addition, clinical trials on special patient populations (patients with pulmonary disease and renal insufficiency) are evaluated. Each article reviewed will conclude with a discussion of relevance, focus on adverse event profile, and clinical usefulness.

A Comparision of the Effect of Sugammadex on the Recovery Period and Postoperative Residual Block in Young Elderly and Middle-Aged Elderly Patients

BACKGROUND

The importance of the characteristics of anesthesia and postoperative residual curarization (PORC) in the elderly population should be a growing concern in this century.

AIMS

To investigate the effect of sugammadex on the duration of the recovery from neuromuscular blocking agents and postoperative residual curarization in the young elderly and middle-aged elderly patients who underwent elective laparoscopic cholecystectomy, followed by a train of four (TOF) watch monitorization.

STUDY DESIGN

Prospective clinical trial study.

METHODS

Sixty patients over the age of 65 with American Society of Anesthesiologists I-III were divided into two groups according to their age (65-74 years old and ≥75 years old). Patients received sugammadex (2.0 mg/kg iv) at the reappearance of the second twitch of the TOF as an agent for reversal of neuromuscular blockage at the end of surgery. Patients were extubated at the time of TOF ≥0.9. The patients' TOF responses were evaluated with regards to PORC in at the 5th minute and were followed up for one hour in the recovery room. Reintubation was applied for those patients who developed PORC and had peripheric oxygen saturation <90% despite being given 6 L oxygen per min with a face mask.

RESULTS

The onset time of neuromuscular blocking agent and time from T2 to achieve TOF ratio 90% (the duration of sugammadex effect) or over were found to be longer in the middle-aged elderly group than in the young elderly group. A statistically significant relationship was found between age and the duration of TOF ratio to reach 0.9 in the same direction. The PORC incidence and rate of reintubation were found to be 1.7% in all patients.

CONCLUSION

In our opinion, it is necessary to remember that the duration of sugammadex effect on the recovery period is prolonged for patients who are aged ≥75 years compared to patients aged between 65-74 years. (ClinicalTrials.gov Identifier: ACTRN12615000758505).

Reversal of rocuronium-induced neuromuscular blockade by sugammadex allows for optimization of neural monitoring of the recurrent laryngeal nerve

OBJECTIVES/HYPOTHESIS

The use of neuromuscular blocking agent may effect intraoperative neuromonitoring (IONM) during thyroid surgery. An enhanced neuromuscular-blockade (NMB) recovery protocol was investigated in a porcine model and subsequently clinically applied during human thyroid neural monitoring surgery.

STUDY DESIGN

Prospective animal and retrospective clinical study.

METHODS

In the animal experiment, 12 piglets were injected with rocuronium 0.6 mg/kg and randomly allocated to receive normal saline, sugammadex 2 mg/kg, or sugammadex 4 mg/kg to compare the recovery of laryngeal electromyography (EMG). In a subsequent clinical application study, 50 patients who underwent thyroidectomy with IONM followed an enhanced NMB recovery protocol-rocuronium 0.6 mg/kg at anesthesia induction and sugammadex 2 mg/kg at the operation start. The train-of-four (TOF) ratio was used for continuous quantitative monitoring of neuromuscular transmission.

RESULTS

In our porcine model, it took 49 ± 15, 13.2 ± 5.6, and 4.2 ± 1.5 minutes for the 80% recovery of laryngeal EMG after injection of saline, sugammadex 2 mg/kg, and sugammadex 4 mg/kg, respectively. In subsequent clinical human application, the TOF ratio recovered from 0 to >0.9 within 5 minutes after administration of sugammadex 2 mg/kg at the operation start. All patients had positive and high EMG amplitude at the early stage of the operation, and intubation was without difficulty in 96% of patients.

CONCLUSIONS

Both porcine modeling and clinical human application demonstrated that sugammadex 2 mg/kg allows effective and rapid restoration of neuromuscular function suppressed by rocuronium. Implementation of this enhanced NMB recovery protocol assures optimal conditions for tracheal intubation as well as IONM in thyroid surgery.

LEVEL OF EVIDENCE

NA.

The combination of sugammadex and neostigmine can reduce the dosage of sugammadex during recovery from the moderate neuromuscular blockade

BACKGROUND

Sugammadex is a novel neuromuscular reversal agent, but its associated hypersensitivity reaction and high cost have been obstacles to its widespread use. In the interest of reducing the necessary dosage of sugammadex, the reversal time of the combined use of sugammadex and neostigmine from moderate neuromuscular blockade were investigated.

METHODS

The patients enrolled ranged in age from 18 to 65 years old with American Society of Anesthesiologists class 1 or 2. The subjects were randomly assigned into one of the four groups (Group S2, S1, SN, and N; n = 30 per group). The reversal agents of each groups were as follows: S2 - sugammadex 2 mg/kg, S1 - sugammadex 1 mg/kg, SN - sugammadex 1 mg/kg + neostigmine 50 µg/kg + glycopyrrolate 10 µg/kg, N - neostigmine 50 µg/kg + glycopyrrolate 10 µg/kg. The time to recovery of the train-of-four (TOF) ratio was checked in each group.

RESULTS

The time to 90% recovery of TOF ratio was 182.6 ± 88.9, 371.1 ± 210.4, 204.3 ± 103.2, 953.2 ± 379.7 sec in group S2, S1, SN and N, respectively. Group SN showed a significantly shorter recovery time than did group S1 and N (P < 0.001). However, statistically significant differences between the S2 and SN groups were not be observed (P = 0.291). No hypersensitivity reactions occurred in all groups.

CONCLUSIONS

For the reversal from rocuronium-induced moderate neuromuscular blockade, the combined use of sugammadex and neostigmine may be helpful to decrease the recovery time and can also reduce the required dosage of sugammadex. However, the increased incidence of systemic muscarinic side effects must be considered.

Anesthesia in a patient with dyskeratosis congenita presenting for urgent subtotal gastrectomy

Dyskeratosis congenita is a rare and complex congenital disease that may complicate surgical treatment and impact anesthetic care. We present the perioperative management of a patient with severe pancytopenia, respiratory dysfunction, and oral leukoplakia who presented for urgent surgery for removal of a gastric hemorrhagic malignant tumor. Important issues in the management of this patient include choice of anesthetic technique, correction of pancytopenia (thrombocytopenia in particular), judicious perioperative fluid management to avoid dilutional coagulopathy, antibiotic prophylaxis, and strict aseptic technique. Careful management of a potentially difficult airway and a higher likelihood of respiratory insufficiency further complicate patient care. Knowledge of this rare disease process and its potential impact on anesthetic management is paramount for safe perioperative patient care.

Efficacy of different doses of sugammadex after continuous infusion of rocuronium

AIM: To evaluate the effects of two different doses of sugammadex after maintenance anesthesia with sevofluorane and remifentanil and deep rocuronium-induced neuromuscular blockade (NMB).

METHODS: Patients between 20 and 65 years of age, with American Society of Anesthesiologists physical status classification I-II, undergoing gynecological surgery were included in a prospective, comparative and randomized study. NMB was induced with an injection of 0.6 mg/kg of rocuronium followed by continuous infusion of 0.3-0.6 mg/kg per hour to maintain a deep block. Anesthesia was maintained with sevofluorane and remifentanil. Finally, when surgery was finished, a bolus of 2 mg/kg (group A) or 4 mg/kg (group B) of sugammadex was applied when the NMB first response in the train-of-four was reached. The primary clinical endpoint was time to recovery to a train-of-four ratio of 0.9. Other variables recorded were the time until recovery of train-of-four ratio of 0.7, 0.8, hemodynamic variables (arterial blood pressure and heart rate at baseline, starting sugammadex, and minutes 2, 5 and 10) and adverse events were presented after one hour in the post-anesthesia care unit.

RESULTS: Thirty-two patients were included in the study: 16 patients in group A and 16 patients in group B. Only 14 patients each group were recorded because arterial pressure values were lost in two patients from each group in minute 10. The two groups were comparable. Median recovery time from starting of sugammadex administration to a train-of-four ratio of 0.9 in group A and B was 129 and 110 s, respectively. The estimated difference in recovery time between groups was 24 s (95%CI: 0 to 45 s, Hodges-Lehmann estimator), entirely within the predefined equivalence interval. Times to recovery to train-of-four ratios of 0.8 (group A: 101 s; group B: 82.5 s) and 0.7 (group A: 90 s; group B: 65 s) from start of sugammadex administration were not equivalent between groups. There was not a significant variation in the arterial pressure and heart rate values between the two groups and none of the patients showed any clinical evidence of residual or recurrent NMB.

CONCLUSION: A dose of 2 mg/kg of sugammadex after continuous rocuronium infusion is enough to reverse the NMB when first response in the Train-Of-Four is reached.

Magnesium-induced recurarisation after reversal of rocuronium-induced neuromuscular block with sugammadex

A 61-year-old woman (57 kg, 171 cm) underwent surgery under general anaesthesia with desflurane 5.8-6.1 vol. % end-tidal, remifentanil 0.2-0.4 μg/kg/min and rocuronium 35 mg (0.61 mg/kg). On return of the second twitch in the train-of-four (TOF) stimulation measured by acceleromyography, sugammadex 120 mg (2.1 mg/kg) was given. After complete neuromuscular recovery, magnesium sulphate 3600 mg (60 mg/kg) was injected intravenously over 5 min to treat atrial fibrillation. This was associated with recurarisation with a nadir [first twitch=25%, TOF ratio (TOFR)=67%] 7 min after the start of the magnesium sulphate infusion (magnesium plasma level: 2.67 mM). A spontaneous twitch value and a TOFR of >90% were observed 45 min after the beginning of the magnesium sulphate infusion under general anaesthesia. Rapid infusion of magnesium sulphate may re-establish a sugammadex-reversed, rocuronium-induced neuromuscular block during general anaesthesia, probably because of the high plasma level of magnesium (2.67 mM). Desflurane and a small fraction of unbound rocuronium may amplify the known muscle relaxing effects of magnesium. Intravenous injection of magnesium sulphate is not recommended in patients after general anaesthesia with neuromuscular relaxants, particularly after sugammadex reversal. Quantitative neuromuscular monitoring should be used for reversing aminosteroid muscle relaxants with sugammadex--particularly in combination with magnesium injection--to prevent post-operative residual curarisation.

Residual neuromuscular block in type II diabetes mellitus after rocuronium: a prospective observational study

BACKGROUND

Diabetes mellitus causes motor nerve dysfunction and degeneration that may alter the response to neuromuscular blocking drugs.

OBJECTIVE

To analyse the risk of residual neuromuscular block (RNMB) induced by rocuronium given in standard doses to patients with type 2 diabetes mellitus (T2DM).

DESIGN

A prospective, observational study.

SETTINGS

Hospital San Jorge, Huesca and Hospital San Pedro, Logroño, Spain, from December 2011 to June 2012.

PATIENTS

T2DM patients with no diabetic neuropathy or neurological symptoms (n = 32) and healthy controls (n = 39).

INTERVENTION

All participants received a single dose of rocuronium 0.6 mg kg. Neuromuscular block was monitored throughout surgery until a train of four (TOF) ratio of at least 0.9 was achieved.

MAIN OUTCOME

Time from rocuronium injection to a TOF ratio of at least 0.9 (DURTOF90).

SECONDARY OUTCOMES

Time to reappearance of T1, T2, T3 and T4 of TOF; glycosylated haemoglobin values (HbA1c); correlation between blood glucose control and DURTOF90 in the group of diabetic patients.

RESULTS

No significant differences in age, weight, renal function or other characteristics interfering with neuromuscular block were seen between T2DM patients and controls. DURTOF90 was significantly longer in the group of T2DM patients than in the controls (109.86 vs. 84.77 min, P = 0.001). Times to reappearance of T1, T2, T3 and T4 of TOF were also significantly longer in the T2DM group. No correlation was found between HbA1C and DURTOF90 values. In addition, DURTOF90 did not appear to be related to elevated blood glucose levels.

CONCLUSION

Diabetic patients, even in the absence of complications, have an increased risk of RNMB after rocuronium administration compared with those without diabetes. Poorer glycaemic control of diabetes does not appear to increase the risk. Appropriate dose and vigilant monitoring of the neuromuscular blocker is helpful in patients with T2DM.

Scientometrics of anesthetic drugs and their techniques of administration, 1984-2013

The aim of this study was to assess progress in the field of anesthetic drugs over the past 30 years using scientometric indices: popularity indices (general and specific), representing the proportion of articles on a drug relative to all articles in the field of anesthetics (general index) or the subfield of a specific class of anesthetics (specific index); index of change, representing the degree of growth in publications on a topic from one period to the next; index of expectations, representing the ratio of the number of articles on a topic in the top 20 journals relative to the number of articles in all (>5,000) biomedical journals covered by PubMed; and index of ultimate success, representing a publication outcome when a new drug takes the place of a common drug previously used for the same purpose. Publications on 58 topics were assessed during six 5-year periods from 1984 to 2013. Our analysis showed that during 2009–2013, out of seven anesthetics with a high general popularity index (≥2.0), only two were introduced after 1980, ie, the inhaled anesthetic sevoflurane and the local anesthetic ropivacaine; however, only sevoflurane had a high index of expectations (12.1). Among anesthetic adjuncts, in 2009–2013, only one agent, sugammadex, had both an extremely high index of change (>100) and a high index of expectations (25.0), reflecting the novelty of its mechanism of action. The index of ultimate success was positive with three anesthetics, ie, lidocaine, isoflurane, and propofol, all of which were introduced much longer than 30 years ago. For the past 30 years, there were no new anesthetics that have produced changes in scientometric indices indicating real progress.

Rapid reversal of neuromuscular blockade by sugammadex after continuous infusion of rocuronium in patients with liver dysfunction undergoing hepatic surgery

OBJECTIVE

Sugammadex rapidly reverses neuromuscular blockade (NMB) induced by rocuronium. NMB induced by rocuronium is prolonged in patients with liver dysfunction, because the drug is mainly excreted into the bile. However, the efficacy and safety of sugammadex in terms of reversing rocuronium-induced NMB in patients with liver dysfunction undergoing hepatic surgery have not been evaluated. This observational study investigated the efficacy and safety of sugammadex after continuous infusion of rocuronium in patients with liver dysfunction undergoing hepatic surgery.

METHODS

Remifentanil/propofol anesthesia was administered to 31 patients: 15 patients in the control group, and 16 patients from a group with liver dysfunction. Rocuronium (0.6 mg/kg) was administered, followed by continuous infusion. The enrolled patients were then subdivided into two groups according to the dose of sugammadex. In the first group a single dose of sugammadex (2.0 mg/kg) was given at the reappearance of the second twitch (T2). In the second group a single dose of sugammadex (4.0 mg/kg) was given at the first twitch response if T2 did not reappear in 15 minutes after stopping rocuronium. The primary outcome was time from administration of sugammadex to recovery of a train-of-four ratio to 0.9.

RESULTS

The dose of rocuronium required in the liver dysfunction group was lower than that in the control group (6.2 vs. 8.2 μg/kg/min, p = 0.002). The mean time from the administration of sugammadex to recovery of the train-of-four ratio to 0.9 was not significantly different between the liver dysfunction group and the control group (2.2 minutes vs. 2.0 minutes in the 2 mg/kg administration group, p = 0.44 and 1.9 minutes vs. 1.7 minutes in the 4 mg/kg administration group, p = 0.70, respectively). No evidence of recurarization was observed in any of the patients. Most of the adverse events were found to be mild and such events were not related to the use of sugammadex. None of the patients was eliminated from the study because of an adverse event. One patient died due to cholestatic liver cirrhosis because of repeated hepatic surgery.

CONCLUSION

Sugammadex can rapidly reverse NMB after continuous infusion of rocuronium in patients with liver dysfunction undergoing hepatic surgery. Sugammadex was found to be safe and well tolerated. However, further studies of sugammadex under similar conditions should be conducted involving a large number of patients with liver dysfunction undergoing hepatic surgery.

Safety and Efficacy of Sugammadex for Neuromuscular Blockade Reversal

Since its first human use in 2005, the γ-cyclodextrin sugammadex (Org 25969) has had the potential to become the reversal agent of choice, for rocuronium- or vecuronium-induced neuromuscular blockade. Sugammadex binds to the aminosteroid neuromuscular blocker, encapsulating it and extracting it from the neuromuscular junction, effectively ceasing activity and allowing neuromuscular transmission to recover rapidly. Phases I–III and subsequent trials have found sugammadex to be safe and effective in a wide range of doses and for the reversal of a range of depth of muscle relaxation in healthy volunteers and a variety of disease states. Sugammadex use may allow refinement of anesthetic practice and improvement in surgical conditions, through the maintenance of deep neuromuscular blockade right to the end of surgery, with subsequent rapid reversal. Debate remains about the use of sugammadex in the treatment of rocuronium anaphylaxis and airway emergencies. The high price of sugammadex currently prohibits its routine use, but if the price falls, after expiry of its patent, it may become cost-effective as a readily available agent in certain specific clinical situations. Serious adverse reactions have occurred in less than 1% of patients and are most commonly because of hypersensitivity. No deaths have been reported, but caution is advised in neonates, pediatrics, and pregnancy where data are lacking.

Rocuronium and sugammadex in patients with myasthenia gravis undergoing thymectomy

BACKGROUND

The use of neuromuscular blocking agents is still controversial in myasthenic patients but rocuronium could be useful after the introduction of sugammadex as a selective antagonist. The aim of the study was to evaluate the use of rocuronium-sugammadex in myasthenic patients undergoing thoracoscopic thymectomy.

METHODS

After ethical approval, 10 myasthenic patients undergoing videothoracoscopic-assisted thymectomy were enrolled in the study. Neuromuscular block was achieved with 0.3 mg/kg rocuronium and additional doses were given according to train-of-four (TOF) monitoring or movement of the diaphragm. Sugammadex 2 mg/kg was given after surgery. Recovery time (time to obtain a TOF value > 0.9) was recorded for all subjects.

RESULT

All patients were extubated in the operating room after administration of sugammadex. Mean rocuronium dose was 48 mg and the average operation time was 62 min. Recovery time after sugammadex administration was 111 s (min 35; max 240).

CONCLUSIONS

A rapid recovery of neuromuscular function was found in myasthenic patients receiving rocuronium when sugammadex was used for reversal. This combination could be a rational alternative for myasthenic patients for whom neuromuscular blockade is mandatory during surgery.

Introduction of sugammadex as standard reversal agent: Impact on the incidence of residual neuromuscular blockade and postoperative patient outcome

Background:

The aim of this prospective audit was to investigate clinical practice related to muscle relaxant reversal and the impact made by the recent introduction of sugammadex on patient outcome at a tertiary teaching hospital.

Methods:

Data from all patients intubated at our institution during two epochs of seven consecutive days each was collected prospectively. Directly prior to extubation, the train-of-four (TOF) ratio was assessed quantitatively by an independent observer. Postoperative outcome parameters were complications in the recovery room and radiological diagnosed atelectasis or pneumonia within 30 days.

Results:

Data from 146 patients were analysed. Three reversal strategies were used: no reversal, neostigmine or sugammadex. The TOF ratio was less than 0.7 in 17 patients (nine no reversal, eight neostigmine) and less than 0.9 in 47 patients (24 no reversal, 19 neostigmine, four sugammadex). Those reversed with sugammadex showed fewer episodes of postoperative oxygen desaturation (15% vs. 33%; P<0.05). TOF ratios of less than 0.7 (P<0.05) and also <0.9 (P<0.01) were more likely associated with X-ray results consistent with postoperative atelectasis or pneumonia.

Conclusions:

Our results suggest a significant impact of residual paralysis on patient outcome. The use of sugammadex resulted in the lowest incidence of residual paralysis.

Unrestricted access to sugammadex: impact on neuromuscular blocking agent choice, reversal practice and associated healthcare costs

Sugammadex is known to rapidly and completely reverse the effects of amino-steroidal neuromuscular blocking agents. However, the high costs of sugammadex have so far prevented its introduction as the standard reversal agent in most healthcare systems. At the Royal Perth Hospital, sugammadex was recently introduced as an unrestricted alternative to neostigmine for the reversal of amino-steroidal neuromuscular blocking agents. The aim of this retrospective observational audit was to investigate the impact of this change on clinical practice and associated healthcare costs. Data from all patients intubated during a one-month period in April to May 2010 and for a similar period in 2011 were retrospectively collected and the use of neuromuscular blocking agents and reversal agents were identified and the associated costs were calculated. More steroidal neuromuscular blocking agents and sugammadex (+743%), but less glycopyrrolate and neostigmine (-48%) were used in 2011. Using the manufacturer's list price, muscle relaxation and reversal costs increased from about A$42 per case to about A$127 per case. Between the investigated time periods no differences were found for anaesthesia time, operating time or time spent in the post anaesthesia care unit. However, there was a statistically significant decrease in the time between surgery and discharge (median 2.0 vs 2.2 days). While the design of the audit was such that no inferences can be made about the cause of this change, this is an interesting observation worthy of further investigation.

Reversal of rocuronium-induced neuromuscular block with sugammadex and resulting histopathological effects in rat kidneys

BACKGROUND

This study investigated the effect of injection of rocuronium or sugammadex alone and rocuronium + sugammadex on urea, creatinine, electrolyte levels, and histopathological findings in rats.

METHODS

Thirty-six Sprague-Dawley male rats were divided to receive intravenously 16 or 96 mg/kg sugammadex, 1 mg/kg rocuronium, 1 mg/kg rocuronium + 16 mg/kg sugammadex, or 1 mg/kg rocuronium + 96 mg/kg sugammadex. The control group received an equal volume of physiological serum. Rats receiving rocuronium were ventilated until resumption of spontaneous ventilation and followed for 72 h. Blood samples were withdrawn from the tail vein to measure urea, creatinine, and electrolyte values; then both kidneys were excised, and the tissues were used for histopathological examination.

RESULTS

Rats receiving rocuronium and high doses of sugammadex (96 mg/kg) showed increased glomerular vacuolation, tubular dilatation, vascular vacuolation and hypertrophy, lymphocyte infiltration, and tubular cell sloughing compared to the control group (p = 0.002). Biochemical markers of renal function were not significantly altered after treatment with high doses of sugammadex.

CONCLUSION

The elimination half-life of the rocuronium-sugammadex complex was found to be greater than that of free rocuronium or sugammadex, which led to marginal histopathological changes in the kidney without affecting any renal functions.

Neuromuscular blocking agents for electroconvulsive therapy: a systematic review

Electroconvulsive therapy (ECT) is the transcutaneous application of small electrical stimuli to the brain to induce generalised seizures for the treatment of selected psychiatric disorders. The clinical indications for ECT as an effective therapeutic modality have been considerably expanded since its introduction. Anaesthesia and neuromuscular blocking agents (NMBAs) are required to ensure patients' safety during ECT. The optimal dose of muscle relaxant for ECT reduces muscle contractions without inducing complete paralysis. Slight residual motor convulsive activity is helpful in ascertaining that a seizure has occurred, while total paralysis prolongs the procedure unnecessarily. Suxamethonium is commonly used, but nondepolarising NMBAs are indicated in patients with certain comorbidities. In this review, we summarise current concepts of NMBA management for ECT.

Correlation between cardiac output and reversibility of rocuronium-induced moderate neuromuscular block with sugammadex

BACKGROUND

The aim of this study was to evaluate the correlation between cardiac output (CO) and reversibility of rocuronium-induced moderate neuromuscular block with sugammadex in elderly patients.

METHODS

Fifty elderly (≥ 65 years) patients were enrolled in this study. During 1.0-1.5% end-tidal sevoflurane and remifentanil anaesthesia, contraction of the adductor pollicis muscle in response to ulnar nerve stimulation was acceleromyographically quantified. All patients initially received 1 mg/kg rocuronium followed by 0.2 mg/kg whenever the second twitch T2 of the train-of-four (TOF) response reappeared. CO was measured throughout the study using a FloTrac™/Vigileo™ monitor. After completion of surgery and at the reappearance of T2, the time required for a bolus dose of 2 mg/kg sugammadex to facilitate recovery to a TOF ratio of 0.9 was recorded, and its correlation with CO was analysed.

RESULTS

Adequate recovery of neuromuscular block was achieved after sugammadex in all patients. Mean CO at the time of reversal with sugammadex was 5.3 l/min (1.3), and recovery time to a TOF ratio of 0.9 was 173.4 s (54.8). A statistically significant inverse correlation was seen between the time to recovery to a TOF ratio of 0.9 and CO [reversal time (s) = -27.7·CO + 298.7, R(2)  = 0.461, P < 0.0001].

CONCLUSIONS

The time to reach a TOF ratio of 0.9 following sugammadex is dependent on CO in elderly patients.

Population pharmacokinetic-pharmacodynamic analysis for sugammadex-mediated reversal of rocuronium-induced neuromuscular blockade

AIMS

An integrated population pharmacokinetic-pharmacodynamic model was developed with the following aims: to simultaneously describe pharmacokinetic behaviour of sugammadex and rocuronium; to establish the pharmacokinetic-pharmacodynamic model for rocuronium-induced neuromuscular blockade and reversal by sugammadex; to evaluate covariate effects; and to explore, by simulation, typical covariate effects on reversal time.

METHODS

Data (n= 446) from eight sugammadex clinical studies covering men, women, non-Asians, Asians, paediatrics, adults and the elderly, with various degrees of renal impairment, were used. Modelling and simulation techniques based on physiological principles were applied to capture rocuronium and sugammadex pharmacokinetics and pharmacodynamics and to identify and quantify covariate effects.

RESULTS

Sugammadex pharmacokinetics were affected by renal function, bodyweight and race, and rocuronium pharmacokinetics were affected by age, renal function and race. Sevoflurane potentiated rocuronium-induced neuromuscular blockade. Posterior predictive checks and bootstrapping illustrated the accuracy and robustness of the model. External validation showed concordance between observed and predicted reversal times, but interindividual variability in reversal time was pronounced. Simulated reversal times in typical adults were 0.8, 1.5 and 1.4 min upon reversal with sugammadex 16 mg kg(-1) 3 min after rocuronium, sugammadex 4 mg kg(-1) during deep neuromuscular blockade and sugammadex 2 mg kg(-1) during moderate blockade, respectively. Simulations indicated that reversal times were faster in paediatric patients and slightly slower in elderly patients compared with adults. Renal function did not affect reversal time.

CONCLUSIONS

Simulations of the therapeutic dosing regimens demonstrated limited impact of age, renal function and sevoflurane use, as predicted reversal time in typical subjects was always <2 min.

Reversibility of rocuronium-induced profound neuromuscular block with sugammadex in younger and older patients

BACKGROUND

This study compared the reversibility of rocuronium-induced profound neuromuscular block with sugammadex in younger and older patients.

METHODS

Fifteen younger (20-50 yr) and 15 older (≥70 yr) patients were sequentially enrolled in this study. After induction of anaesthesia and laryngeal mask insertion, contraction of the adductor pollicis muscle in response to ulnar nerve stimulation was quantified using acceleromyography during 1.0-1.5% end-tidal sevoflurane and remifentanil anaesthesia. All patients initially received rocuronium 1 mg kg(-1), followed by 0.02 mg kg(-1) when a post-tetanic count (PTC) of 1 or 2 was observed. After completion of surgery, at reappearance of 1-2 PTC, the time required for a single bolus dose of 4 mg kg(-1) sugammadex to produce recovery to a train-of-four (TOF) ratio of 0.9 was recorded.

RESULTS

There were no differences in the total dose of rocuronium administered between the younger [mean (sd): 93.4 (17.5) mg] and the older [97.5 (32.2) mg] groups. In all patients, adequate recovery of the TOF ratio to 0.9 was achieved after administration of sugammadex, although it was significantly slower in the older [3.6 (0.7) min, P<0.0001] than in the younger group [1.3 (0.3) min]. There were no clinical events attributable to recurarization.

CONCLUSIONS

Sugammadex can adequately restore neuromuscular function in older patients, although a longer time is required to recover from profound rocuronium-induced neuromuscular block than in younger patients.