Neuromuscular blocking agents for acute respiratory distress syndrome

Potential Impact of Subphenotyping in Pharmacologic Management of Acute Respiratory Distress Syndrome

Background: Acute respiratory distress syndrome (ARDS) is an acute inflammatory process in the lungs associated with high morbidity and mortality. Previous research has studied both nonpharmacologic and pharmacologic interventions aimed at targeting this inflammatory process and improving ventilation. Hypothesis: To date, only nonpharmacologic interventions including lung protective ventilation, prone positioning, and high positive end-expiratory pressure ventilation strategies have resulted in significant improvements in patient outcomes. Given the high mortality associated with ARDS despite these advancements, interest in subphenotyping has grown, aiming to improve diagnosis and develop personalized treatment approaches. Data Collection: Previous trials evaluating pharmacologic therapies in heterogeneous populations have primarily demonstrated no positive effect, but hope to show benefit when targeting specific subphenotypes, thus increasing their efficacy, while simultaneously decreasing adverse effects. Results: Although most studies evaluating pharmacologic therapies for ARDS have not demonstrated a mortality benefit, there is limited data evaluating pharmacologic therapies in ARDS subphenotypes, which have found promising results. Neuromuscular blocking agents, corticosteroids, and simvastatin have resulted in a mortality benefit when used in patients with the hyper-inflammatory ARDS subphenotype. Therapeutic Opinion: The use of subphenotyping could revolutionize the way ARDS therapies are applied and therefore improve outcomes while also limiting the adverse effects associated with their ineffective use. Future studies should evaluate ARDS subphenotypes and their response to pharmacologic intervention to advance this area of precision medicine.

Neuromuscular Blocking Agent Use in Critical Care Transport Not Associated With Intubation

OBJECTIVE

Variable indications exist for neuromuscular blocking agents (NMBAs) in the critical care transport setting beyond facilitation of intubation.

METHODS

This retrospective cohort study included adult patients (≥ 18 years) who underwent critical care transport from July 1, 2020, to May 2, 2023, and received NMBAs during transport that was not associated with intubation. The primary outcome was the indication for NMBA administration. Secondary outcomes included the characterization of NMBA use, mean Richmond Agitation Sedation Scale score before NMBA administration, sedation strategy used, and continuation of NMBAs within 48 hours of hospital admission.

RESULTS

One hundred twenty-six patients met the inclusion criteria. The most common indication for NMBA administration was ventilator dyssynchrony (n = 71, 56.4%). The majority of patients received rocuronium during transport (n = 113, 89.7%). The mean pre-NMBA Richmond Agitation Sedation Scale score was -3.7 ± 2.4. The most common sedation strategy was a combination of continuous infusion and bolus sedatives (76.2%). One hundred (79.4%) patients had sedation changes in response to NMBA administration. Seventy-two (57.1%) received NMBAs during the first 48 hours of their intensive care unit admission.

CONCLUSION

NMBAs were frequently administered for ventilator dyssynchrony and continuation of prior therapy. Optimization opportunities exist to ensure adequate deep sedation and reassessment of NMBA indication.

Atracurium Versus Cisatracurium in the Treatment of Acute Respiratory Distress Syndrome

Background: Neuromuscular blocking agents are one of the few medication classes that have demonstrated a clinical benefit in patients with severe acute respiratory distress syndrome (ARDS). However, most literature utilized cisatracurium, and utilization of atracurium is limited to 1 small study. Objective: The purpose of this study was to provide further evidence comparing the safety and efficacy of atracurium versus cisatracurium for the treatment of ARDS. Methods: This multicenter, retrospective, observational cohort noninferiority study was conducted at 3 hospitals within a tertiary health care system. We included subjects diagnosed with ARDS who received either atracurium or cisatracurium for at least 12 hours. The primary outcome measured the change in PaO2/FiO2 (P/F) ratio from baseline to 48 hours after initiation. Results: Baseline characteristics were similar between groups except for a higher median age and a higher proportion of subjects who were COVID-positive in the atracurium group. There were also some noted differences in the baseline P/F ratios. In a multivariable model adjusting for baseline characteristics, the change in the P/F ratio for atracurium was noninferior to cisatracurium at 24, 48, and 72 hours. A significant cost reduction, measured as cost per patient per day, was seen with the use of atracurium ($14.81-$25.16 vs $33.86-$41.91). Conclusion: Atracurium appears to be a safe and cheaper alternative agent in the management of ARDS.

Research Progress on Phenotypic Classification of Acute Respiratory Distress Syndrome: A Narrative Review

Acute respiratory distress syndrome (ARDS) is a clinical syndrome that is characterized by an acute onset and refractory hypoxemia. It remains an important contributor to high mortality in critically ill patients, and the majority of clinical randomized controlled trials on ARDS provide underwhelming findings, which is attributed in large part to its pathophysiological and clinical heterogeneity, among other aspects. It is now widely accepted that ARDS is highly heterogeneous, growing evidences support this. ARDS phenotypic and subphenotypic studies aim to further differentiate and identify ARDS heterogeneity in the hope that clinicians can benefit from it, then can diagnose ARDS faster and more accurately and provide targeted treatments. This review collates and evaluates the major phenotype-related research advances of recent years, with a specific focus on ARDS biomarkers and clinical factors.

Intensive Care Unit-Acquired Weakness and the COVID-19 Pandemic: A Clinical Review

Patients with severe cases of coronavirus disease 2019 (COVID-19) often become critically ill requiring intensive care unit (ICU) management. These individuals are at risk for developing ICU-acquired weakness (ICUAW), a multifactorial condition in which polyneuropathy, myopathy, and/or disuse muscle atrophy result in motor weakness. This weakness is thought to contribute to the long-term functional disability frequently observed in survivors of critical illness. This review discusses the current evidence regarding the epidemiology, pathophysiology, evaluation, risk factors, and rehabilitation-specific management of ICUAW in patients with COVID-19. Due to the novelty of COVID-19, the exact prevalence of ICUAW is not well delineated among COVID-19 patients. However, ICUAW has been reported in this population with retrospective studies showing weakness occurring in up to 45.5% of patients with severe COVID-19. There are multiple risk factors for developing ICUAW among COVID-19 patients which include premorbid health status, sepsis, multiple organ failure, mechanical ventilation, immobilization, neuromuscular blockade, corticosteroid use, and glycemic control. ICUAW is more likely to occur after prolonged mechanical ventilation and long hospital stays and can be diagnosed with manual muscle and electrodiagnostic testing. While the long-term sequela of COVID-19 after ICU stays is not fully studied, increasing evidence indicates significant risk for this population developing long-term functional impairments. Establishing post-acute rehabilitation programs for COVID-19 survivors will be important for recovery of endurance, mobility, and function. This article is protected by copyright. All rights reserved.

Obesity as a Risk Factor for Failure to Wean from ECMO: A Systematic Review and Meta-Analysis

Purpose

Obesity has been associated with an increased risk of respiratory complications and other systemic illnesses. Respiratory dynamics in an obese patient, combined with modified lung physiology of ARDS, present a significant challenge in managing obese patients with ARDS. Many physicians think of obesity as a relative contraindication to ECMO. We performed a meta-analysis to see the effect of obesity on weaning from ECMO and survival to hospital discharge.

Methods

We searched online databases for studies on ECMO and obesity. The search yielded 49 citations in total; after extensive review, six studies were assessed and qualified to be included in the final analysis. Patients were stratified into BMI >30 kg/m2 (obese) and BMI < 30 kg/m2 (nonobese).

Results

In meta-analysis, there was a total sample population of 1285 patients, with 466 in the obese group and 819 in the nonobese group. There was no significant difference in weaning from ECMO when compared between obese and nonobese patients, with a risk ratio of 1.03 and 95% confidence interval (CI) of 0.94-1.13 (heterogeneity: chi2 = 7.44, df = 4 (p=0.11), I 2 = 46%). There was no significant difference in survival rates between obese and nonobese patients who were treated with ECMO during hospitalization, with a risk ratio of 1.04 and 95% CI of 0.86-1.25 (heterogeneity: Tau2 0.03, chi2 = 14.61, df = 5 (p=0.01), I 2 = 66%).

Conclusion

Our findings show no significant difference in survival and weaning from ECMO in obese vs. nonobese patients. ECMO therapy should not be withheld from obese patients, as obesity is not a contraindication to ECMO.

Ventilation management in acute respiratory failure related to COVID-19 versus ARDS from another origin - a descriptive narrative review

Introduction

It is uncertain whether ventilation in patients with acute respiratory failure related to coronavirus disease 2019 (COVID-19) differs from that in patients with acute respiratory distress syndrome (ARDS) from another origin.

Areas covered

We undertook two literature searches in PubMed to identify observational studies reporting on ventilation management––one in patients with acute respiratory failure related to COVID-19, and one in patients with ARDS from another origin. The searches identified 14 studies in patients with acute respiratory failure related to COVID-19, and 8 studies in patients with ARDS from another origin.

Expert opinion

In patients with acute respiratory failure related to COVID-19, ventilation management seems to be similar to that of patients with ARDS from another origin. The future lies in studies focused on personalized treatment of ARDS of all origins, including COVID-19.

The Implementation of Protocol-Based Utilization of Neuromuscular Blocking Agent Using Clinical Variables in Acute Respiratory Distress Syndrome Patients

Supplemental Digital Content is available in the text.

Objectives:

The recent conflicting data on the mortality benefit of neuromuscular blocking agents in acute respiratory distress syndrome and the potential adverse effects of continuous neuromuscular blocking agent necessitates that these medications should be used judiciously with dose reduction in mind. The aims of the study were to improve the process of care by provider education of neuromuscular blocking agent titration and monitoring and to determine the impact of clinical endpoint based neuromuscular blocking agent titration protocol.

Design:

We conducted a proof-of-concept historically controlled study of protocol-based intervention standardizing paralytic monitoring and titration using clinical variables. Education of the protocol was provided to ICU staff via bedside teaching and workshops. The primary outcomes were the time to reach goal paralysis and cumulative neuromuscular blocking agent dose. Secondary outcomes included maintenance of deeper sedation (Richmond Agitation and Sedation Scale –5) prior to neuromuscular blocking agent initiation, total time on mechanical ventilation, length of stay, and mortality.

Setting:

Medical ICU at a quaternary academic hospital between March 2019 and June 2020.

Patients:

Adult severe acute respiratory distress syndrome (Pao₂/Fio₂ <150) patients requiring neuromuscular blocking agent for greater than or equal to 12 hours. Eighty-two patients fulfilled inclusion criteria, 46 in the control group and 36 in the intervention group.

Interventions:

Education and implementation of standardized protocol.

Measurements and Main Results:

Compared with the control group, the time to reach goal paralysis in the intervention group was shorter (8.55 ± 9.4 vs 2.63 ± 5.9 hr; p < 0.0001) on significantly lower dose of cisatracurium (total dose 1,897.96 ± 1,241.0 vs 562.72 ± 546.7 mg; p < 0.0001 and the rate 5.84 ± 2.66 vs 1.99 ± 0.95 µg/kg/min; p < 0.0001). Deeper sedation was achieved at the time of initiation of neuromuscular blocking agent in the intervention arm (mean Richmond Agitation and Sedation Scale –3.3 ± 1.9 vs –4.3 ± 1.7; p = 0.015). There was no significant difference in total time on mechanical ventilation, length of ICU stay, length of hospital stay, and mortality between the two groups.

Conclusions:

Implementation of comprehensive education, standardization of sedation prior to neuromuscular blocking agent initiation, integration of clinical variables in determining paralysis achievement, and proper use of peripheral nerve stimulation served as optimal strategies for the titration and monitoring of neuromuscular blocking agent in acute respiratory distress syndrome. This reduced drug utilization while continuing to achieve benefit without causing adverse effects.

Early neuromuscular blocking agents for adults with acute respiratory distress syndrome: a systematic review, meta-analysis and meta-regression

OBJECTIVE

To determine whether neuromuscular blocking agents (NMBAs) can decrease the mortality of patients with acute respiratory distress syndrome (ARDS) and improve their clinical outcomes.

DESIGN

Systematic review, meta-analysis and meta-regression.

DATA SOURCES

PubMed, Embase, Cochrane Library, Web of Science and ClinicalTrials.gov.

METHODS

Randomised controlled trials (RCTs) comparing the treatment effect of NMBAs with that of placebo (or traditional treatment) in patients with ARDS were carefully selected. The primary outcome was 90-day mortality. The secondary outcomes were 21-28 days mortality, NMBA-related complications (barotrauma, pneumothorax and intensive care unit (ICU)-acquired muscle weakness), days free of ventilation and days not in the ICU by day 28, Medical Research Council score, Acute Physiology and Chronic Health Evaluation II score and arterial oxygen tension (PaO₂)/fractional inspired oxygen (FiO₂) (at 48 hours and 72 hours). Random-effects meta-regression was used to explore models involving potential moderators. Trial sequential analysis was performed to estimate the cumulative effect on mortality across RCTs.

RESULTS

NMBAs were not associated with reduced 90-day mortality (risk ratio (RR) 0.85; 95% CI 0.66 to 1.09; p=0.20). However, they decreased the 21-28 days mortality (RR 0.71; 95% CI 0.53 to 0.96; p=0.02) and the rates of pneumothorax (RR 0.46; 95% CI 0.28 to 0.77; p=0.003) and barotrauma (RR 0.56; 95% CI 0.37 to 0.86; p=0.008). In addition, NMBAs increased PaO₂/FiO₂ at 48 hours (mean difference (MD) 18.91; 95% CI 4.29 to 33.53; p=0.01) and 72 hours (MD 12.27; 95% CI 4.65 to 19.89; p=0.002). Meta-regression revealed an association between sample size (p=0.042) and short-term mortality. Publication year (p=0.050), sedation strategy (p=0.047) and sample size (p=0.046) were independently associated with PaO₂/FiO₂ at 48 hours.

CONCLUSIONS

In summary, the results suggested that use of NMBAs might reduce 21-28 days mortality, NMBA-related complications and oxygenation. However, NMBAs did not reduce the 90-day mortality of patients with ARDS, which contradicts a previous meta-analysis.

PROSPERO REGISTRATION NUMBER

CRD42019139440.

Myorelaxants in ARDS patients

Neuromuscular blocking agents (NMBAs) inhibit patient-initiated active breath and the risk of high tidal volumes and consequent high transpulmonary pressure swings, and minimize patient/ ventilator asynchrony in acute respiratory distress syndrome (ARDS). Minimization of volutrauma and ventilator-induced lung injury (VILI) results in a lower incidence of barotrauma, improved oxygenation and a decrease in circulating proinflammatory markers. Recent randomized clinical trials did not reveal harmful muscular effects during a short course of NMBAs. The use of NMBAs should be considered during the early phase of severe ARDS for patients to facilitate lung protective ventilation or prone positioning only after optimising mechanical ventilation and sedation. The use of NMBAs should be integrated in a global strategy including the reduction of tidal volume, the rational use of PEEP, prone positioning and the use of a ventilatory mode allowing spontaneous ventilation as soon as possible. Partial neuromuscular blockade should be evaluated in future trials.

[Recommendations of the Working Groups from the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) for the management of adult critically ill patients in the coronavirus disease (COVID-19)]

On March 11, 2020, the Director-General of the World Health Organization (WHO) declared the disease caused by SARS-CoV-2 (COVID-19) as a pandemic. The spread and evolution of the pandemic is overwhelming the healthcare systems of dozens of countries and has led to a myriad of opinion papers, contingency plans, case series and emerging trials. Covering all this literature is complex. Briefly and synthetically, in line with the previous recommendations of the Working Groups, the Spanish Society of Intensive, Critical Medicine and Coronary Units (SEMICYUC) has prepared this series of basic recommendations for patient care in the context of the pandemic.

Recommendations of the Working Groups from the Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC) for the management of adult critically ill patients in the coronavirus disease (COVID-19)

On March 11, 2020, the Director-General of the World Health Organization (WHO) declared the disease caused by SARS-CoV-2 (COVID-19) as a pandemic. The spread and evolution of the pandemic is overwhelming the healthcare systems of dozens of countries and has led to a myriad of opinion papers, contingency plans, case series and emerging trials. Covering all this literature is complex. Briefly and synthetically, in line with the previous recommendations of the Working Groups, the Spanish Society of Intensive, Critical Medicine and Coronary Units (SEMICYUC) has prepared this series of basic recommendations for patient care in the context of the pandemic.

COVID-19 and neuromuscular disorders

The coronavirus 2019 (COVID-19) pandemic has potential to disproportionately and severely affect patients with neuromuscular disorders. In a short period of time, it has already caused reorganization of neuromuscular clinical care delivery and education, which will likely have lasting effects on the field. This article reviews (1) potential neuromuscular complications of COVID-19, (2) assessment and mitigation of COVID-19-related risk for patients with preexisting neuromuscular disease, (3) guidance for management of immunosuppressive and immunomodulatory therapies, (4) practical guidance regarding neuromuscular care delivery, telemedicine, and education, and (5) effect on neuromuscular research. We outline key unanswered clinical questions and highlight the need for team-based and interspecialty collaboration. Primary goals of clinical research during this time are to develop evidence-based best practices and to minimize morbidity and mortality related to COVID-19 for patients with neuromuscular disorders.

Neuromuscular blocking agents for acute respiratory distress syndrome: an updated meta-analysis of randomized controlled trials

Backgrounds

The aim of this study is investigating the benefits and harms of neuromuscular blocking agents (NMBAs) in patients with acute respiratory distress syndrome (ARDS).

Methods

We comprehensively searched PubMed, EMBASE, and Cochrane library for randomized controlled trials comparing NMBAs to any other comparator. We pooled data using relative risk (RR) for dichotomous outcomes and weighted mean difference (WMD) for continuous outcomes, with 95% confidence intervals. We assessed the quality of included studies using the Cochrane tool and levels of evidence using the GRADE method.

Results

Finally, six RCTs (n = 1557 patients) were eligible for analysis. The results showed NMBAs use was not associated with reduced 28 days mortality (RR 0.78; 95% CI, 0.58 to 1.06; P = 0.11), 90 days mortality (RR, 0.92; 95% CI, 0.81 to 1.04; P = 0.16), and intensive care unit (ICU) mortality (RR, 0.90; 95% CI, 0.79 to 1.03; P = 0.13) in patients with ARDS. However, 21–28 days mortality was slightly lower in patients received NMBAs (RR 0.73; 95% CI, 0.54 to 0.99; P = 0.04; I² = 53%). Besides, NMBAs use could improve the PaO₂/FiO₂ ratio at 48 and 72 h, decrease plateau pressure and PEEP at 72 h. Additionally, NMBAs had no significant effects on days free of ventilation at day 28 (WMD, 0.55; 95% CI, − 0.46 to 1.57; P = 0.29), days not in ICU at day 28 (WMD, 0.12; 95% CI, − 0.85 to 1.08; P = 0.82), ICU-acquired weakness (RR, 1.23; 95% CI, 0.99 to 1.93; P = 0.06). Finally, NMBAs use was associated with a lower risk of barotrauma (RR, 0.55; 95% CI, 0.35 to 0.85; P = 0.007).

Conclusion

In patients with respiratory distress syndrome, NMBAs may be beneficial in reverse refractory hypoxemia and may be associated with reduced short-term mortality and incidence of barotrauma. However, there is no significant effects of NMBAs on mid-term and long-term mortality, and further studies are required.