Neostigmine-based reversal of intermediate acting neuromuscular blocking agents to prevent postoperative residual paralysis: A systematic review

Development of Different Separation Techniques for Impurity Profiling of Neostigmine Methylsulfate: A Comparative Study

Different separation techniques have been employed to resolve mixtures of multicomponent preparations over the last few decades. They could be efficiently applied for impurity profiling of active drug substances. Impurity profiling has become a critical procedure in pharmaceutical companies to comply with numerous regulatory standards. Isolation and characterization of impurities are crucial for obtaining data that proves biological safety and efficacy. In this contribution, different HPLC, capillary electrophoresis (CE) and TLC-densitometric methods were developed for the determination of neostigmine methylsulfate (NEO) along with 3-hydroxyphenyltrimethyl ammonium methylsulfate (3-HPA) and 3-dimethylaminophenol (DAP) as its impurities in the presence of citric acid. The linearity for NEO was attained in the range of 5-120 μg/mL and 10-60 μg/mL for the HPLC and CE methods, respectively. Regarding the impurities, linearity was obtained over the range of 10-30 μg/mL for 3-HPA and 5-30 μg/mL for DAP in the two proposed methods. For the TLC method, NEO and DAP were determined within the range of 1-11 μg/band, whereas 3-HPA was assayed over the range of 2-12 μg/band. The suggested methods can be securely utilized for routine analysis of the cited components in quality control laboratories.

New advances in clinical application of neostigmine: no longer focusing solely on increasing skeletal muscle strength

Neostigmine is a clinical cholinesterase inhibitor, that is, commonly used to enhance the function of the cholinergic neuromuscular junction. Recent studies have shown that neostigmine regulates the immune-inflammatory response through the cholinergic anti-inflammatory pathway, affecting perioperative neurocognitive function. This article reviews the relevant research evidence over the past 20 years, intending to provide new perspectives and strategies for the clinical application of neostigmine.

Perioperative neuromuscular blockade. 2020 update of the SEDAR (Sociedad Española de Anestesiología y Reanimación) recommendations

We present an update of the 2020 Recommendations on neuromuscular blockade of the SEDAR. The previous ones dated 2009. A modified Delphi consensus analysis (experts, working group, and previous extensive bibliographic revision) 10 recommendations were produced1: neuromuscular blocking agents were recommended for endotracheal intubation and to avoid faringo-laryngeal and tracheal lesions, including critical care patients.2 We recommend not to use neuromuscular blocking agents for routine insertion of supraglotic airway devices, and to use it only in cases of airway obstruction or endotracheal intubation through the device.3 We recommend to use a rapid action neuromuscular blocking agent with an hypnotic in rapid sequence induction of anesthesia.4 We recommend profound neuromuscular block in laparoscopic surgery.5 We recommend quantitative monitoring of neuromuscular blockade during the whole surgical procedure, provided neuromuscular blocking agents have been used.6 We recommend quantitative monitoring through ulnar nerve stimulation and response evaluation of the adductor pollicis brevis, acceleromyography being the clinical standard.7 We recommend a recovery of neuromuscular block of at least TOFr ≥ 0.9 to avoid postoperative residual neuromuscular blockade.8 We recommend drug reversal of neuromuscular block at the end of general anesthetic, before extubation, provided a TOFr ≥ 0.9 has not been reached.9 We recommend to choose anticholinesterases for neuromuscular block reversal only if TOF≥2 and a TOFr ≥ 0.9 has not been attained.10 We recommend to choose sugammadex instead of anticholinesterases for reversal of neuromuscular blockade induced with rocuronium.

The effect of neostigmine on postoperative delirium after colon carcinoma surgery: a randomized, double-blind, controlled trial

Background

Postoperative delirium (POD) is a critical complication in patients accepting colon carcinoma surgery. Neostigmine, as a cholinesterase inhibitor, can enhance the transmission of cholinergic transmitters in synaptic space, and play an important role in maintaining the normal level of cognition, attention and consciousness. The objective of this study was to investigate the effect of neostigmine on POD and clinical prognosis.

Methods

A randomized, double-blind controlled trial was implemented in Qingdao Municipal Hospital Affiliated to Qingdao University. A total of 454 patients aged 40 to 90 years old accepted colon carcinoma surgery were enrolled between June 7, 2020, and June 7, 2021, with final follow-up on December 8, 2021. Patients were randomly assigned to two groups: the neostigmine group (group N) and the placebo group (group P), the patients in group N were injected with 0.04 mg/kg neostigmine and 0.02 mg/kg atropine intravenously. The primary endpoint was the incidence of POD, researchers evaluated the occurrence of POD by the Confusion Assessment Method (CAM) twice daily (at 10 a.m. and 2 p.m.) during the first 7 postoperative days, POD severity was assessed by the Memorial Delirium Assessment Scale (MDAS). The secondary endpoints were the extubating time, postanesthesia care unit (PACU) time, the incidence of various postoperative complications, length of hospital stays, and 6 months postoperative mortality.

Results

The incidence of POD was 20.20% (81/401), including 19.39% (38/196) in group N and 20.98% (43/205) in group P. There was no significant statistical significance in the incidence of POD between group N and group P (P > 0.05); Compared to group P, the extubating time and PACU time in group N were significantly reduced (P < 0.001), the incidence of postoperative pulmonary complications (POPCs) decreased significantly in group N (P < 0.05), while no significant differences were observed in postoperative hospital stay and mortality in 6 months between the two groups (P > 0.05).

Conclusion

For patients accepted colon carcinoma surgery, neostigmine did not significantly reduce the incidence of POD, postoperative mortality and postoperative hospital stay, while it indeed reduced the extubating time, PACU time and the incidence of POPCs.

Trial registration

The randomized, double-blind, controlled trial was registered retrospectively at www.chictr.org.cn on 07/06/2020 (ChiCTR2000033639).

Neuromuscular block in patients 80 years and older: a prospective, controlled study

Background

An increasing number of patients older than 80 years are undergoing anesthesia, but little information is available regarding pharmacodynamic effects of myorelaxants in this population. This study aims to compare the time course of rocuronium neuromuscular block in patients ≥ 80 years with those of younger adults.

Methods

Under total intravenous anesthesia with propofol and sufentanil, time course of a bolus of rocuronium 0.6 mg/kg neuromuscular block was assessed with acceleromyography in patients ≥ 80 and in patients 20–50 years old. Onset time, clinical duration, duration until 90% and 100% recovery of baseline were determined.

Results

Data from 32 patients were analyzed, 16 were ≥ 80 years and 16 were 20–50 years old. Demographic data are shown in Table 1. In the group ≥ 80, onset time was 190 s ± 46 s compared to 123 s ± 40 s in the group 20–50, P < 0.001 and the clinical duration was 52 [48–69.5] min and 36 [34–41] min, respectively, P < 0.001. Duration to 90% recovery of baseline was 77.5 [71–88.5] min and duration to 100% recovery of baseline was 91.2 [82.2–98] min in patients ≥ 80 years and the corresponding values in the patients 20–50 years old were 53.5 [49–55.5] min and 59.5 [56.5–70.25] min, respectively, P < 0.001.

Conclusion

Compared to younger adults rocuronium shifted in patients ≥ 80 years from a rapid onset, intermediate acting compound to a slower onset, long-acting compound.

Trial registration

ClinicalTrials.gov identifier: NCT03551652 (29/05/2018).

A118G polymorphism of OPRM1 gene caused different morphine consumption in female patients after total knee replacement

BACKGROUND

We intended to clarify the effect of gender and A118G polymorphism of Opioid Receptor μ1 (OPRM1) on the required morphine for patients to maintain Visual Analogue Scale ≦ 3 for post-operative pain control after total knee replacement (TKR).

METHODS

With approval from Institutional Review Board (IRB) and obtainment of informed consents, 111 patients undergoing primary TKR were enrolled without violating the exclusion criteria, including previous history of allergy to morphine, alcohol or substance abuse, use of psychotropic medications, morbid obesity of body mass index (BMI) > 40 kg/m², chronic pain with evidence of central sensitization, and uncooperative use of patient controlled analgesia (PCA) device. The amount of PCA-delivered morphine for pain control and the 'demand' (the count of button pushing for requiring pain medication from PCA) were recorded at 3, 6, 12, 24, 36, 48 and 72 h after the operation. One-way ANOVA with post-hoc test by Scheffe's method was adopted for statistical analysis of each variant (AA, AG, GG). The side-effects (nausea, vomiting and sedation) from morphine were recorded. P < 0.05 was considered to be statistically significant.

RESULTS

With sequencing by ABI PRISM 310 Genetic Analyser, we disclosed that the allele frequency was 75.5% for the A allele (female: 77.5%, male: 69.6%) and 24.5% for the G allele (female: 22.5%, male: 30.4%). The frequency of genotype occurrence was 61.3% for AA, 24.3% for AG and 14.4% for GG. Female patients of homozygous G118G of OPRMI required more morphine from PCA device for post-operative pain control than patients of AA and AG genotypes. No significant difference in morphine consumption for post-operative pain control was disclosed among three genotypes for male patients.

CONCLUSIONS

The impact caused by G118G polymorphism of OPRM1 on requirement of morphine consumption for post-operative pain control is potentially gender-linked.

Prolonged neuromuscular block after rocuronium administration in laparoscopic pyloromyotomy patients: A retrospective bayesian regression analysis

BACKGROUND

Infants undergoing pyloromyotomy are at a high risk of aspiration, making rapid sequence induction the preferred method of induction. Since succinylcholine use in infants can be associated with complications, rocuronium is frequently substituted despite its prolonged duration of action.

AIMS

To examine the likelihood of non-reversibility to neostigmine at the end of surgery in laparoscopic pyloromyotomies and its correlation to both rocuronium dose and out of operating room time.

METHODS

Patients who underwent laparoscopic pyloromyotomy for infantile hypertrophic pyloric stenosis, received rocuronium, and were reversed with neostigmine were included. Bayesian multivariable logistic regression was utilized to determine the probability of non-reversibility, and Bayesian multivariable median regression was performed to ascertain the correlation between out of operating room time and non-reversibility.

RESULTS

306 patients were analyzed with a median surgical duration of 19 min (interquartile range 16 to 23). 74% received succinylcholine for intubation followed by rocuronium, and the remaining received rocuronium alone. The median rocuronium dose was 0.41 mg/kg (interquartile range 0.27 - 0.56 mg/kg). Prolonged block occurred in 68 (22.2%) patients. There was a non-trivial probability of prolonged block with low rocuronium doses, and each 0.1 mg/kg increase in total rocuronium dose was associated with an odds ratio of 1.36 (95% credible interval: 1.17-1.58) of neostigmine non-reversibility at the end of surgery. Non-reversibility was correlated with a substantial increase in median out of operating room time (13.4 min, 95% credible interval: 5.5-20.8 min), which was compounded by high rocuronium dosing (2.2 min increase per 0.1 mg/kg for doses greater than 0.5 mg/kg, 95% credible interval: 0.7-3.6 min).

CONCLUSION

Prolonged blockade can occur from rocuronium administration in infants undergoing pyloromyotomy even at low doses. Therefore, consideration of appropriate rocuronium dosing or the use of sugammadex should be considered.

The future of neuromuscular blocking agents

PURPOSE OF REVIEW

The present review provides a summary of the literature on recent development of new neuromuscular blocking agents and presents clinically well established and new reversal agents.

RECENT FINDINGS

Anesthesiologists are still waiting for the ideal neuromuscular blocking agent with a succinylcholine-like rapid onset and offset without side effects. Recent drug development led to a new series of neuromuscular compounds, called the chlorofumarates such as gantacurium, CW002, and CW011. These drugs have a promising pharmacodynamic profile; importantly, they can rapidly be reversed by L-cysteine adduction without relevant side effects. In addition, a new spectrum of reversal agents are currently examined in preclinical studies: adamgammadex sodium, a modified γ-cyclodextrin derivate that forms an inactive tight inclusion complex with rocuronium or vecuronium and calabadions, capable of reversing both benzylisoquinolines and steroidal neuromuscular blocking agents.

SUMMARY

Although the recent advancements in neuromuscular research are very promising, to date, the presented drugs are currently not available for clinical use. Clinical studies will determine the role of these developments in anesthesia practice. Therefore, well established combinations such as rocuronium-sugammadex are popular in clinical practice to offer quick paralysis for intubation and to optimize surgical conditions, while providing a fast neuromuscular recovery at the end of surgery.

Epidemiology and outcomes of residual neuromuscular blockade: A systematic review of observational studies

OBJECTIVES

Complete reversal of neuromuscular blockade (NMB) is important for patient safety and prognosis following surgical procedures involving NMB agents (NMBAs). Published evidence on the epidemiology and consequences of residual neuromuscular blockade (rNMB; incomplete neuromuscular recovery) in real-world clinical settings is lacking with advances in NMB management. Therefore, we aimed to examine the burden of rNMB and its associated clinical, economic and humanistic outcomes using a systematic review framework.

REVIEW METHODS

Electronic and conference database searches were performed to include observational studies examining rNMB or related outcomes in adults undergoing surgery and receiving NMBAs with or without NMBA antagonists.

RESULTS

Of 1438 screened abstracts, 58 studies with 25,277 total patients were included. Inconsistent definitions of rNMB were reported across studies with 44 (76%) and 29 (50%) studies utilizing quantitative and qualitative measures to detect rNMB, respectively. The most common definition of rNMB was train-of-four ratio (TOFR) <0.9 (29 studies) and TOFR <0.7 (16 studies) measured at post-anesthesia care unit (PACU) entry. For TOFR <0.9 at PACU entry, rNMB incidence ranged from 0% to 90.5% (median 30%) overall; 0% to 16.0% in the sugammadex (SUG) group; 3.5% to 90.5% in the neostigmine (NEO) group; and 15% to 89% in the spontaneous recovery (SR) group. Twenty-one studies reported clinical outcomes (reintubation, mild hypoxemia, or a respiratory event) or resource utilization outcomes (hospital/PACU length of stay [LOS]) by presence/absence of rNMB. Patients with rNMB had higher rates of acute respiratory events compared to those without rNMB.

CONCLUSIONS

Real-world observational studies show a significant burden of rNMB and associated health sequelae, though rNMB measures were not reported consistently across studies. Appropriate quantitative measurement is needed to accurately identify rNMB, and interventions are needed to reduce its burden and associated adverse outcomes.

Optimised reversal without train-of-four monitoring versus reversal using quantitative train-of-four monitoring: An equivalence study

Background and Aims:

Less residual paralysis in recovery room was demonstrated when train-of-four (TOF) monitoring was applied. The aim of this study was to know whether optimisation of neostigmine reversal without TOF monitoring was equivalent to reversal using TOF monitoring.

Methods:

Seventy two patients, aged 18–60 years, undergoing elective surgery under general anaesthesia (sevoflurane and rocuronium) with intubation were randomised into two interventions: an optimised neostigmine reversal strategy without TOF monitoring (group A, n = 36) and a neostigmine reversal strategy using quantitative TOF monitoring (group B, n = 36). Per-protocol analysis was performed to compare incidence of residual paralysis in the recovery room between the two groups.

Results:

Six residual paralyses occurred in group A in the recovery room, whereas one case occurred in group B. The equivalence test showed that the 95% confidence interval of this study was outside the range of equivalence margin (15%). The absolute difference was 13.9%: standard error (SE) =0.068 (P = 0.107; 95% confidence interval (CI): 1%, 27.2%). No subjects had TOF ratio <0.70 in the recovery room. The TOF ratio in the recovery room did not differ between the two groups (mean difference: −2.58; P = 0.05; 95% CI: −5.20, 0.29). One respiratory adverse event occurred in this study.

Conclusion:

An optimised reversal strategy without TOF monitoring is not equivalent to a reversal strategy based on quantitative TOF monitoring. TOF monitoring should be used whenever applicable, although neostigmine is optimised.

Reevaluation and update on efficacy and safety of neostigmine for reversal of neuromuscular blockade

Postoperative residual neuromuscular block is a serious threat which endangers the patient safety. Neostigmine has been the most commonly used anticholinesterase for the pharmacological reversal of neuromuscular blockade. Although newer agents have been introduced recently, neostigmine has some irreplaceable advantages, including broad-spectrum reversal of all nondepolarizing neuromuscular blocking drugs, low cost, and availability of more related data for clinical practice to refer to. Neostigmine is also noticed to have some drawbacks, such as the inability to reverse profound and deep blockade, potential induction of muscle weakness, cardiovascular adverse effects, and so on. Data on the usage of neostigmine in the geriatric and the pediatric population are still insufficient. Some discrepancies are observed in the results from previous studies which need further investigation. However, recent studies offer some renewed information. Regarding both efficacy and safety, the key for successful reversal of neuromuscular blockade is to use neostigmine “appropriately,” optimizing the dosage and timing of administration under close monitoring.