An Update on Management of Adult Patients with Acute Respiratory Distress Syndrome: An Official American Thoracic Society Clinical Practice Guideline.

Background: This document updates previously published Clinical Practice Guidelines for the management of patients with acute respiratory distress syndrome (ARDS), incorporating new evidence addressing the use of corticosteroids, venovenous extracorporeal membrane oxygenation, neuromuscular blocking agents, and positive end-expiratory pressure (PEEP). Methods: We summarized evidence addressing four "PICO questions" (patient, intervention, comparison, and outcome). A multidisciplinary panel with expertise in ARDS used the Grading of Recommendations, Assessment, Development, and Evaluation framework to develop clinical recommendations. Results: We suggest the use of: 1) corticosteroids for patients with ARDS (conditional recommendation, moderate certainty of evidence), 2) venovenous extracorporeal membrane oxygenation in selected patients with severe ARDS (conditional recommendation, low certainty of evidence), 3) neuromuscular blockers in patients with early severe ARDS (conditional recommendation, low certainty of evidence), and 4) higher PEEP without lung recruitment maneuvers as opposed to lower PEEP in patients with moderate to severe ARDS (conditional recommendation, low to moderate certainty), and 5) we recommend against using prolonged lung recruitment maneuvers in patients with moderate to severe ARDS (strong recommendation, moderate certainty). Conclusions: We provide updated evidence-based recommendations for the management of ARDS. Individual patient and illness characteristics should be factored into clinical decision making and implementation of these recommendations while additional evidence is generated from much-needed clinical trials.

El bloqueo del plano del músculo erector espinal antes de la litotricia extracorpórea por ondas de choque reduce el tiempo de fluoroscopia y facilita el tratamiento de la litiasis renal: estudio prospectivo aleatorizado / Erector spinae plane block prior to extracorporeal shock wave lithotripsy decreases fluoroscopy time and promise a comfortable procedure for renal stones: a prospective randomized study

Introducción y objetivos Comparar la eficacia del bloqueo del plano del erector espinal (BPEE) y el diclofenaco sódico intramuscular (IM) en términos del manejo del dolor y su impacto sobre el estado libre de cálculos en pacientes sometidos a litotricia extracorpórea de ondas de choque (LEOCh). Pacientes y materiales El estudio incluyó a pacientes sometidos a LEOCh por litiasis renal en nuestro centro. Los pacientes fueron asignados aleatoriamente a los grupos de BPEE (Grupo 1: n = 31) y de 75 mg de diclofenaco sódico IM (Grupo 2: n = 30). Se registraron los datos demográficos de los pacientes, el tiempo de fluoroscopia durante la LEOCh, el número de focalizaciones, el total de disparos administrados, el voltaje, las tasas libre de cálculos (TLC), el método de analgesia, el número de sesiones de LEOCh, la puntuación de la Escala Visual Analógica (EVA) la localización de los cálculos, el tamaño máximo de los cálculos, el volumen de los cálculos y las unidades Hounsfield (UH). Resultados Un total de 61 pacientes fueron incluidos en el estudio. No hubo diferencias estadísticamente significativas entre los dos grupos en cuanto al tamaño, el volumen y la densidad de los cálculos, la duración de la LEOCh, el total de disparos administradas, el voltaje, el índice de masa corporal (IMC), el estado libre de cálculos y la localización de los cálculos. El tiempo de fluoroscopia y el número de veces que fue necesario focalizar el cálculo fueron significativamente inferiores en el grupo 1 con respecto al grupo 2 (p:0,002, p:0,021, respectivamente). La puntuación EVA fue significativamente inferior en el grupo 1 en comparación con el grupo 2 (p<0,001). Conclusiones Observamos que la puntuación EVA del grupo BPEE era menor que la del grupo de diclofenaco sódico IM y, aunque no de manera estadísticamente significativa, conseguimos una tasa libre de cálculos más alta en la primera sesión en el grupo BPEE. ... (AU)

Introduction and Objectives To compare the efficacy of erector spinae plane block (ESPB) and intramuscular (i.m.) diclofenac sodium in regard to pain management and impact on stone-free status in patients undergoing SWL. Patients or Materials The study included patients who underwent SWL for kidney stones in our institution. The patients were randomly assigned to the ESPB (Group 1: n = 31) and i.m. 75 mg diclofenac sodium (Group 2: n = 30) groups. The demographic data of the patients, fluoroscopy time during SWL, number of need of targeting, total shocks given, voltage, stone free rates (SFR), analgesy method, number of SWL sessions, VAS score, stone location, maximum stone size, stone volume and Hounsfield unit (HU) were also recorded. Results A total of 61 patients were included the study. There was no statistically significant difference between the two groups according to stone size, volume and density, SWL duration, total shocks given, voltage, BMI, stone-free status and stone location. Fluoroscopy time and number of need for stone targeting were significantly lower in group 1 than group 2 (p:0.002, p:0.021, respectively). The VAS score was significantly lower for group 1 compared to group 2 (p<0.001). Conclusions We observed that the VAS score was lower in the ESPB group compared to i.m. diclofenac sodium group and although it was not statistically significant, we achieved a higher rate of stone-free status in the first session in ESPB group. Most importantly, the patients in the ESPB group were exposed to less fluoroscopy and radiation. (AU)

Pharmacotherapy optimization for rapid sequence intubation in the emergency department.

PURPOSE: Rapid-sequence intubation (RSI) is the process of administering a sedative and neuromuscular blocking agent (NMBA) in rapid succession to facilitate endotracheal intubation. It is the most common and preferred method for intubation of patients presenting to the emergency department (ED). The selection and use of medications to facilitate RSI is critical for success. The purpose of this review is to describe pharmacotherapies used during the RSI process, discuss current clinical controversies in RSI medication selection, and review pharmacotherapy considerations for alternative intubation methods. SUMMARY: There are several steps to the intubation process requiring medication considerations, including pretreatment, induction, paralysis, and post-intubation sedation and analgesia. Pretreatment medications include atropine, lidocaine, and fentanyl; but use of these agents in clinical practice has fallen out of favor as there is limited evidence for their use outside of select clinical scenarios. There are several options for induction agents, though etomidate and ketamine are the most used due to their more favorable hemodynamic profiles. Currently there is retrospective evidence that etomidate may produce less hypotension than ketamine in patients presenting with shock or sepsis. Succinylcholine and rocuronium are the preferred neuromuscular blocking agents, and the literature suggests minimal differences between succinylcholine and high dose rocuronium in first-pass success rates. Selection between the two is based on patient specific factors, half-life and adverse effect profiles. Finally, medication-assisted preoxygenation and awake intubation are less common methods for intubation in the ED but require different considerations for medication use. AREAS FOR FUTURE RESEARCH: The optimal selection, dosing, and administration of RSI medications is complicated, and further research is needed in several areas. Additional prospective studies are needed to determine optimal induction agent selection and dosing in patients presenting with shock or sepsis. Controversy exists over optimal medication administration order (paralytic first vs induction first) and medication dosing in obese patients, but there is insufficient evidence to significantly alter current practices regarding medication dosing and administration. Further research examining awareness with paralysis during RSI is needed before definitive and widespread practice changes to medication use during RSI can be made.

Comparison of a Modern Digital Mechanomyograph to a Mechanomyograph Utilizing an Archival Grass Force Transducer.

BACKGROUND: Mechanomyography is the traditional gold standard research technique for quantitative assessment of neuromuscular blockade. Mechanomyography directly measures the isometric force generated by the thumb in response to ulnar nerve stimulation. Researchers must construct their own mechanomyographs since commercial instruments are no longer available. A mechanomyograph was constructed, and its performance was compared against an archival mechanomyography system from the 1970s that utilized an FT-10 Grass force transducer, hypothesizing that train-of-four ratios recorded on each device would be equivalent. METHODS: A mechanomyograph was constructed using 3D-printed components and modern electronics. An archival mechanomyography system was assembled from original components, including an FT-10 Grass force transducer. Signal digitization for computerized data collection was utilized instead of the original paper strip chart recorder. Both devices were calibrated with standard weights to demonstrate linear voltage response curves. The mechanomyographs were affixed to opposite arms of patients undergoing surgery, and the train-of-four ratio was measured during the onset and recovery from rocuronium neuromuscular blockade. RESULTS: Calibration measurements exhibited a positive linear association between voltage output and calibration weights with a linear correlation coefficient of 1.00 for both mechanomyography devices. The new mechanomyograph had better precision and measurement sensitivity than the archival system: 5.3 mV versus 15.5 mV and 1.6 mV versus 5.7 mV, respectively (P < 0.001 for both). A total of 767 pairs of train-of-four ratio measurements obtained from eight patients had positive linear association (R 2 = 0.94; P < 0.001). Bland-Altman analysis resulted in bias of 3.8% and limits of agreement of -13% and 21%. CONCLUSIONS: The new mechanomyograph resulted in similar train-of-four ratio measurements compared to an archival mechanomyography system utilizing an FT-10 Grass force transducer. These results demonstrated continuity of gold standard measurement of neuromuscular blockade spanning nearly 50 yr, despite significant changes in the instrumentation technology.

Critical Care Pharmacist Attitudes and Perceptions of Neuromuscular Blocker Infusions in ARDS.

BACKGROUND: Current critical care pharmacist (CCP) practices and perceptions related to neuromuscular infusion (NMBI) use for acute respiratory distress syndrome (ARDS) maybe different with the COVID-19 pandemic and the publication of 2020 NMBI practice guidelines. OBJECTIVE: To evaluate CCP practices and perceptions regarding NMBI use for patients with moderate-severe ARDS. METHODS: We developed, tested, and electronically administered a questionnaire (7 parent-, 42 sub-questions) to 409 American College of Clinical Pharmacy (ACCP) Critical Care Practice and Research Network members in 12 geographically diverse states. The questionnaire focused on adults with moderate-severe ARDS (PaO2:FiO2<150) whose causes of dyssynchrony were addressed. Two reminders were sent at 10-day intervals. RESULTS: Respondents [131/409 (32%)] primarily worked in a medical intensive care unit (ICU) 102 (78%). Compared to COVID-negative(-) ARDS patients, COVID positive(+) ARDS patients were twice as likely to receive a NMBI (34 ± 18 vs.16 ± 17%; P < 0.01). Respondents somewhat/strongly agreed a NMBI should be reserved until after trials of deep sedation (112, 86%) or proning (92, 81%) and that NMBI reduced barotrauma (88, 67%), dyssynchrony (87, 66%), and plateau pressure (79, 60%). Few respondents somewhat/strongly agreed that a NMBI should be initiated at ARDS onset (23, 18%) or that NMBI reduced 90-day mortality (12, 10%). Only 2/14 potential NMBI risks [paralysis awareness (101, 82%) and prolonged muscle weakness (84, 68%)] were frequently reported to be of high/very high concern. Multiple NMBI titration targets were assessed as very/extremely important including arterial pH (109, 88%), dyssynchrony (107, 86%), and PaO2: FiO2 ratio (82, 66%). Train-of-four (55, 44%) and BIS monitoring (36, 29%) were deemed less important. Preferred NMBI discontinuation criteria included absence of dysschrony (84, 69%) and use ≥48 hour (72, 59%). CONCLUSIONS AND RELEVANCE: Current critical care pharmacists believe NMBI for ARDS patients are best reserved until after trials of deep sedation or proning; unique considerations exist in COVID+ patients. Our results should be considered when ICU NMBI protocols are being developed and bedside decisions regarding NMBI use in ARDS are being formulated.

Neuromuscular Weakness and Paralysis Produced by Snakebite Envenoming: Mechanisms and Proposed Standards for Clinical Assessment.

Respiratory and airway-protective muscle weakness caused by the blockade of neuromuscular transmission is a major cause of early mortality from snakebite envenoming (SBE). Once weakness is manifest, antivenom appears to be of limited effectiveness in improving neuromuscular function. Herein, we review the topic of venom-induced neuromuscular blockade and consider the utility of adopting clinical management methods originally developed for the safe use of neuromuscular blocking agents by anesthesiologists in operating rooms and critical care units. Failure to quantify neuromuscular weakness in SBE is predicted to cause the same significant morbidity that is associated with failure to do so in the context of using a clinical neuromuscular block in surgery and critical care. The quantitative monitoring of a neuromuscular block, and an understanding of its neurophysiological characteristics, enables an objective measurement of weakness that may otherwise be overlooked by traditional clinical examination at the bedside. This is important for the initial assessment and the monitoring of recovery from neurotoxic envenoming. Adopting these methods will also be critical to the conduct of future clinical trials of toxin-inhibiting drugs and antivenoms being tested for the reversal of venom-induced neuromuscular block.

Effect of Remifentanil vs Neuromuscular Blockers During Rapid Sequence Intubation on Successful Intubation Without Major Complications Among Patients at Risk of Aspiration: A Randomized Clinical Trial.

Importance: It is uncertain whether a rapid-onset opioid is noninferior to a rapid-onset neuromuscular blocker during rapid sequence intubation when used in conjunction with a hypnotic agent. Objective: To determine whether remifentanil is noninferior to rapid-onset neuromuscular blockers for rapid sequence intubation. Design, Setting, and Participants: Multicenter, randomized, open-label, noninferiority trial among 1150 adults at risk of aspiration (fasting for <6 hours, bowel occlusion, recent trauma, or severe gastroesophageal reflux) who underwent tracheal intubation in the operating room at 15 hospitals in France from October 2019 to April 2021. Follow-up was completed on May 15, 2021. Interventions: Patients were randomized to receive neuromuscular blockers (1 mg/kg of succinylcholine or rocuronium; n = 575) or remifentanil (3 to 4 µg/kg; n = 575) immediately after injection of a hypnotic. Main Outcomes and Measures: The primary outcome was assessed in all randomized patients (as-randomized population) and in all eligible patients who received assigned treatment (per-protocol population). The primary outcome was successful tracheal intubation on the first attempt without major complications, defined as lung aspiration of digestive content, oxygen desaturation, major hemodynamic instability, sustained arrhythmia, cardiac arrest, and severe anaphylactic reaction. The prespecified noninferiority margin was 7.0%. Results: Among 1150 randomized patients (mean age, 50.7 [SD, 17.4] years; 573 [50%] women), 1130 (98.3%) completed the trial. In the as-randomized population, tracheal intubation on the first attempt without major complications occurred in 374 of 575 patients (66.1%) in the remifentanil group and 408 of 575 (71.6%) in the neuromuscular blocker group (between-group difference adjusted for randomization strata and center, -6.1%; 95% CI, -11.6% to -0.5%; P = .37 for noninferiority), demonstrating inferiority. In the per-protocol population, 374 of 565 patients (66.2%) in the remifentanil group and 403 of 565 (71.3%) in the neuromuscular blocker group had successful intubation without major complications (adjusted difference, -5.7%; 2-sided 95% CI, -11.3% to -0.1%; P = .32 for noninferiority). An adverse event of hemodynamic instability was recorded in 19 of 575 patients (3.3%) with remifentanil and 3 of 575 (0.5%) with neuromuscular blockers (adjusted difference, 2.8%; 95% CI, 1.2%-4.4%). Conclusions and Relevance: Among adults at risk of aspiration during rapid sequence intubation in the operating room, remifentanil, compared with neuromuscular blockers, did not meet the criterion for noninferiority with regard to successful intubation on first attempt without major complications. Although remifentanil was statistically inferior to neuromuscular blockers, the wide confidence interval around the effect estimate remains compatible with noninferiority and limits conclusions about the clinical relevance of the difference. Trial Registration: ClinicalTrials.gov Identifier: NCT03960801.

The use of early neuromuscular blockage in acute respiratory distress syndrome: A systematic review and meta-analyses of randomized clinical trials.

BACKGROUND: Acute Respiratory Distress Syndrome (ARDS) as defined by the Berlin definition has an approximate mortality rate of 40% and no curative treatment. Mutliple therapies have been studied to reduce mortality but only neuromuscular blocking agents show potential benefits on mortality and other complications of ARDS. OBJECTIVE: This review aimed to investigate the efficacy of neuromuscular blockers in ARDS METHODS: Medline, Embase, Cochrane Central and Web of Science were queried on October 1st, 2021. Randomized clinical trials comparing neuromuscular blockers to any comparator in treating ARDS were included. Primary outcome was mortality. Secondary outcomes were ventilator-free days, intensive care (ICU) length of stay (LOS) and complications. Results between sedation levels were examined with a Bayesian Network for Meta-analysis method. RESULTS: We included 6 trials compiling a total of 1557 patients. Neuromuscular blockers compared to any comparator in treating ARDS showed a reduction in mortality (RR 0.79 [95% CI, 0.62 to 0.99]). No difference in ventilator-free days (MD 0.68 [95% CI, -0.50 to 1.85]) or ICU LOS (MD 0.77 [95% CI, -2.99 to 4.54]) were found. A Bayesian Network Meta-analysis yielded no difference in mortality when using light sedation compared to heavy sedation in ARDS. (OR 0.58 [95% CrI, 0.07 to 4.46].) CONCLUSION: Neuromuscular blockers safely reduce mortality. Light sedation potentially has a similar impact on mortality as heavy sedation that carries some burden. A non-inferiority trial comparing both sedation levels may be warranted considering the added value of light sedation.

Physicians' attitudes and perceptions of neuromuscular blocker infusions in ARDS.

PURPOSE: The perceptions and practices of ICU physicians regarding initiating neuromuscular blocker infusions (NMBI) in acute respiratory distress syndrome (ARDS) may not be evidence-based amidst the surge of severe ARDS during the SARS-CoV-2 pandemic and new practice guidelines. We identified ICU physicians' perspectives and practices regarding NMBI use in adults with moderate-severe ARDS. MATERIALS AND METHODS: After extensive development and testing, an electronic survey was distributed to 342 ICU physicians from three geographically-diverse U.S. health systems(n = 12 hospitals). RESULTS: The 173/342 (50.5%) respondents (75% medical) somewhat/strongly agreed a NMBI should be reserved until: after a trial of deep sedation (142, 82%) or proning (59, 34%) and be dose-titrated based on train-of-four monitoring (107, 62%). Of 14 potential NMBI risks, 2 were frequently reported to be of high/very high concern: prolonged muscle weakness with steroid use (135, 79%) and paralysis awareness due to inadequate sedation (114, 67%). Absence of dyssychrony (93, 56%) and use ≥48 h (87, 53%) were preferred NMBI stopping criteria. COVID-19 + ARDS patients were twice as likely to receive a NMBI (56 ± 37 vs. 28 ± 19%, p < 0.01). CONCLUSIONS: Most intensivists agreed NMBI in ARDS should be reserved until after a deep sedation trial. Stopping criteria remain poorly defined. Unique considerations exist regarding the role of paralysis in COVID-19+ ARDS.

Neuromuscular blocking agents in the intensive care unit.

Neuromuscular blocking agents (NMBA) are a controversial therapeutic option in the approach to the critically ill patient. They are not innocuous, and the available evidence does not support their routine use in the intensive care unit. If necessary, monitoring protocols should be established to avoid residual relaxation, adverse effects, and associated complications. This narrative review discusses the current indications for the use of NMBA and the different tools for monitoring blockade in the intensive care unit. However, expanding the use of NMBA in critical settings merits the development of prospective studies.

Factors Associated with the Underuse of Sedatives and Neuromuscular Blocking Agents for Pediatric Emergency Endotracheal Intubation in Korea.

PURPOSE: Rapid sequence intubation (RSI) using sedatives and neuromuscular blocking agents (NMBAs) is recommended for pediatric emergency endotracheal intubation (ETI), but is not frequently performed in Korea. This study aimed to verify factors associated with the underuse of RSI medications. MATERIALS AND METHODS: This multicenter retrospective study reviewed patients aged under 18 years who underwent an ETI within 24 hours of arrival at the emergency department between 2016 and 2019. Any cases of ETI during cardiopulmonary resuscitation were excluded. We investigated the characteristics of the patients, intubators, RSI medications, and outcomes. The study cases were classified into no-medication, sedative-only, and sedative-with-NMBA groups. Multivariable logistic regression analysis of RSI medication use was conducted. RESULTS: A total of 334 cases with a median age of 3.4 years were included in this study. Sedatives and NMBAs were used in 63.8% and 32.9%, respectively. In comparing the no-medication (n=121), sedative-only (n=103), and sedative-with-NMBA (n=110) groups, patient age (median; 1.0 year vs. 2.8 years vs. 11.3 years; p<0.001), underlying medical conditions (77.7% vs. 56.3% vs. 36.4%; p<0.001), and pediatricians as intubators (76.9% vs. 54.4% vs. 17.3%; p<0.001) were different. The factors that influenced sedatives with NMBA use were patient age [for a year increment; adjusted odds ratio (aOR), 1.182; 95% confidence interval (CI), 1.120-1.249], no underlying medical conditions (aOR, 2.109; 95% CI, 1.093-4.070), and intubators other than pediatricians (aOR, 5.123; 95% CI, 2.257-11.626). CONCLUSION: RSI accounted for 32.9% of pediatric emergency ETI in Korea. The underuse of RSI medications is associated with younger patient age, underlying medical conditions, and pediatricians as intubators.

Prone Positioning and Neuromuscular Blocking Agents as Adjunctive Therapies in Mechanically Ventilated Patients with Acute Respiratory Distress Syndrome.

Neuromuscular blocking agents (NMBAs) and prone position (PP) are two major adjunctive therapies that can improve outcome in moderate-to-severe acute respiratory distress syndrome. NMBA should be used once lung-protective mechanical ventilation has been set, for 48 hours or less and as a continuous intravenous infusion. PP should be used as early as possible for long sessions; in COVID-19 its use has exploded. In nonintubated patients, PP might reduce the rate of intubation but not mortality. The goal of this article is to perform a narrative review on the pathophysiological rationale, the clinical effects, and the clinical use and recommendations of both NMBA and PP.

Early short course of neuromuscular blocking agents in patients with COVID-19 ARDS: a propensity score analysis.

BACKGROUND: The role of neuromuscular blocking agents (NMBAs) in coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS) is not fully elucidated. Therefore, we aimed to investigate in COVID-19 patients with moderate-to-severe ARDS the impact of early use of NMBAs on 90-day mortality, through propensity score (PS) matching analysis. METHODS: We analyzed a convenience sample of patients with COVID-19 and moderate-to-severe ARDS, admitted to 244 intensive care units within the COVID-19 Critical Care Consortium, from February 1, 2020, through October 31, 2021. Patients undergoing at least 2 days and up to 3 consecutive days of NMBAs (NMBA treatment), within 48 h from commencement of IMV were compared with subjects who did not receive NMBAs or only upon commencement of IMV (control). The primary objective in the PS-matched cohort was comparison between groups in 90-day in-hospital mortality, assessed through Cox proportional hazard modeling. Secondary objectives were comparisons in the numbers of ventilator-free days (VFD) between day 1 and day 28 and between day 1 and 90 through competing risk regression. RESULTS: Data from 1953 patients were included. After propensity score matching, 210 cases from each group were well matched. In the PS-matched cohort, mean (± SD) age was 60.3 ± 13.2 years and 296 (70.5%) were male and the most common comorbidities were hypertension (56.9%), obesity (41.1%), and diabetes (30.0%). The unadjusted hazard ratio (HR) for death at 90 days in the NMBA treatment vs control group was 1.12 (95% CI 0.79, 1.59, p = 0.534). After adjustment for smoking habit and critical therapeutic covariates, the HR was 1.07 (95% CI 0.72, 1.61, p = 0.729). At 28 days, VFD were 16 (IQR 0-25) and 25 (IQR 7-26) in the NMBA treatment and control groups, respectively (sub-hazard ratio 0.82, 95% CI 0.67, 1.00, p = 0.055). At 90 days, VFD were 77 (IQR 0-87) and 87 (IQR 0-88) (sub-hazard ratio 0.86 (95% CI 0.69, 1.07; p = 0.177). CONCLUSIONS: In patients with COVID-19 and moderate-to-severe ARDS, short course of NMBA treatment, applied early, did not significantly improve 90-day mortality and VFD. In the absence of definitive data from clinical trials, NMBAs should be indicated cautiously in this setting.

Comparison of two pharmacokinetic-pharmacodynamic models of rocuronium bromide during profound neuromuscular block: analysis of estimated and measured post-tetanic count effect.

BACKGROUND: Profound neuromuscular block (NMB) is important in surgeries where complete immobility is considered essential to improve tracheal intubation and surgical conditions. Rocuronium bromide is a commonly used NMB agent. This work describes a noninvasive approach for estimation of post-tetanic count (PTC) based on two pharmacokinetic (PK) models, the Saldien and the De Haes models. The aim was to investigate the rocuronium bromide PK-pharmacodynamic (PD) relationship in estimating the PTC effect during profound NMB. METHODS: In this prospective, non-randomised, observational study, an induction bolus of rocuronium bromide was administered followed by continuous infusion for maintenance of a PTC of 1-2. measured every 3 min. Measurements were analysed as discrete categorical data and by applying the nonlinear mixed-effect modelling approach. Performance of the selected models was evaluated through simulation model-based diagnostics, further assessing the precision of the parameter estimates and the performance of the models at the individual level. RESULTS: Data from 30 adult patients undergoing elective abdominal or neurosurgical procedures were included. Post-tetanic count response profiles during rocuronium bromide infusion were successfully characterised using the population PD analysis. The models showed a good performance for all PTC categories, albeit with a moderate over-prediction of PTC >6. CONCLUSIONS: Our findings indicate that using plasma concentrations of rocuronium bromide estimated with either of the two models, combined with a PD model, provides equal model performance when predicting PTC. These promising results may provide an important advance in guiding rocuronium bromide administration when profound NMB in routine clinical practice is desired.

[A meta-analysis of the effect of neuromuscular blocking agents on oxygenation in patients with acute respiratory distress syndrome].

Objective: To evaluate the effects of neuromuscular blocking agents (NMBA) on oxygenation and respiratory conditions in patients with acute respiratory distress syndrome(ARDS). Methods: English databases such as MEDLINE, Embase and Web of Science were searched online, as well as Chinese databases such as China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database and Wanfang Database. Randomized controlled trials (RCTs) of NMBA therapy for ARDS with publication date up to May 2020 were retrieved. Literature was screened according to inclusion and exclusion criteria, and the main analysis indicators were oxygenation index. Results: A total of 5 RCTs were included, and 1 462 ARDS patients were enrolled. Compared with the control group, the ratio of partial arterial oxygen pressure to fraction of inspired (PaO2)/(FiO2) significantly improved in the intervention group after 72 hours MD=14.39, (95%CI 6.40-22.38, P=0.000 4) and 96 hours of NMBA, but there was no difference between PaO2/FiO2 at 24 and 48 hours (P>0.05).Positive end expiratory pressure (PEEP) significantly decreased at 72 hours (MD=-0.45, 95%CI -0.87--0.03, P=0.04) and 96 hours (MD=-0.82, 95%CI -1.39--0.26, P=0.004) treatment with NMBA, while there was no significant difference in PEEP between 24 and 48 hours after treatment (P>0.05). At 96 h, plateau pressure (Pplat) in the intervention group was significantly lower (MD=-1.69, 95%CI -2.64--0.75, P=0.000 4), and there was no significant difference in Pplat between 24, 48 and 72 h after treatment (P>0.05). Conclusion: The early use of NMBA within 48 hours has a delayed improvement effect on oxygenation and ventilator conditions in ARDS patients.

Neuromuscular Blocker Use in Critically Ill Children: Assessing Mortality Risk by Propensity Score-Weighted Analysis.

OBJECTIVES: We aim to describe the use of continuous infusion of neuromuscular blocking agents in mechanically ventilated critically ill children and to test its association with in-hospital mortality. DESIGN: Multicenter, registry-based, observational, two-cohort-comparison retrospective study using prospectively collected data from a web-based national registry. SETTING: Seventeen PICUs in Italy. PATIENTS: We included children less than 18 years who received mechanical ventilation and a neuromuscular blocking agent infusion from January 2010 to October 2017. A propensity score-weighted Cox regression analysis was used to assess the relationship between the use of neuromuscular blocking agents and in-hospital mortality. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 23,227 patients admitted to the PICUs during the study period, 3,823 patients were included. Patients who received a continuous infusion of neuromuscular blocking agent were more likely to be younger (p < 0.001), ex-premature (p < 0.001), and presenting with less chronic respiratory insufficiency requiring home mechanical ventilation (p < 0.001). Reasons for mechanical ventilation significantly differed between patients who received a continuous infusion of neuromuscular blocking agent and patients who did not receive a continuous infusion of neuromuscular blocking agent, with a higher frequency of respiratory and cardiac diagnosis among patients who received neuromuscular blocking agents compared with other diagnoses (all p < 0.001). The covariates were well balanced in the propensity-weighted cohort. The mortality rate significantly differed among the two cohorts (patients who received a continuous infusion of neuromuscular blocking agent 21% vs patients who did not receive a continuous infusion of neuromuscular blocking agent 11%; p < 0.001 by weighted logistic regression). Patients who received a continuous infusion of neuromuscular blocking agent experienced longer mechanical ventilation and PICU stay (both p < 0.001 by weighted logistic regression). A weighted Cox regression analysis found the use of neuromuscular blocking agents to be a significant predictor of in-hospital mortality both in the unadjusted analysis (hazard ratio, 1.7; 95% CI, 1.3-2.2) and in the adjusted one (hazard ratio, 1.6; 95% CI, 1.2-2.1). CONCLUSIONS: Thirteen percent of mechanically ventilated children in PICUs received neuromuscular blocking agents. When adjusting for selection bias with a propensity score approach, the use of neuromuscular blocking agent was found to be a significant predictor of in-hospital mortality.