Extended neuromuscular blockade in acute respiratory distress syndrome does not increase mortality

The effect of neuromuscular blocking agents uses in acute respiratory distress syndrome: a systematic review and meta-analysis of randomized controlled trials

INTRODUCTION

With the latest addition from Re-evaluation of Systemic Early Neuromuscular Blockade (ROSE) Trial result, the question of mortality benefit from neuromuscular blocking agents (NMBAs) in different studies, remained unanswered. We hypothesize that NMBAs use in moderate to severe acute respiratory distress syndrome (ARDS) does not influence intensive care unit (ICU) mortality.

EVIDENCE ACQUISITION

Pubmed, Embase and the Cochrane Library were searched for randomized controlled trials (RCTs) related to NMBAs infusion in patients with ARDS. The primary outcome was ICU mortality. Secondary outcomes were mortality at day 28 and day 90, oxygenation response to NMBA, ICU length of stay (LOS), ICU Acquired weakness (ICU-AW) and ventilator-free days (VFDs). Meta-analysis was conducted to re-evaluate the effect of NMBAs on patients with ARDS with all randomized controlled trials available.

EVIDENCE SYNTHESIS

NMBAs infusion was associated with reduced ICU mortality (relative ratio [RR]: 0.69; 95% confidence-interval [CI]: 0.55-0.88; I2=0%), but not 28 days mortality (RR: 0.76; 95% CI: 0.57-1.0; I2=49%) and 90-day mortality (RR: 0.87; 95% CI: 0.70-1.08; I2=46%). NMBA use was not associated with increased risk of ICU-AW (RR: 1.21; 95% CI, 0.84 to 1.76; I2=34%).

CONCLUSIONS

Early 48-hour NMBAs infusion in patients with moderate to severe ARDS was associated with reduced ICU mortality without improvement in oxygenation, VFDs, 28-day and 90-day mortality. It did not contribute significantly to ICU-AW. Based on these results, NMBAs infusion is recommended for moderate to severe ARDS for its short-term benefit in early phase of disease. Prolonged use of NMBAs beyond 48 hours requires further study.

Early Neuromuscular Blockade in Children with Pediatric Acute Respiratory Distress Syndrome

Pediatric acute respiratory distress syndrome (PARDS) is a challenging problem with high mortality. Role of neuromuscular blockade in the management of ARDS to date has been controversial, and this study was done to study the role of neuromuscular blockade in children having PARDS and development of associated complications, if any. This was a prospective, case-control study conducted in the pediatric intensive care unit (PICU) of a tertiary care teaching hospital, over a period of 24 months. Patients of age 1 to 18 years who presented with or developed PARDS during their course of hospitalization were included after written informed consent was obtained from their parents and/or guardians. Patients with PARDS requiring invasive mechanical ventilation were partitioned into a case group and a control group. Case group patients were sedated and paralyzed using midazolam (1 µg/kg/min) and vecuronium (1 µg/kg/min), respectively, along with institution of definitive management. Control group patients were given definitive and supportive therapy, but no neuromuscular blocking agents (NMBAs). All patients were followed up for signs and symptoms of myopathy or neuropathy during the entire duration of hospital stay and up to 3 months after discharge. During the study period, 613 patients were admitted to the PICU of which 91 patients qualified as having PARDS. Sepsis was the main etiology in 67 of the 91 patients (73.6%) with PARDS. Fifty-nine patients were included in the study, of which 29 patients were included in the case group and 30 patients were included in the control group. Among the 29 case group patients, 25 patients (86.2%) were successfully extubated. Four patients from the case group expired, while 14 out of 30 control group patients (46.7%) expired. Hypotension was present in 26 case group patients (89.6%), of which all showed resolution within 48 hours of definitive treatment. The mean time to resolution of hypotension was 41.6 hours (standard deviation [SD]: 5.759; range: 24-48) for case group patients, significantly lower ( p  < 0.0001) than the mean time to resolution of 103 hours (SD: 18.995; range: 90-126) for the 10 control group patients with hypotension that survived. Mean oxygenation index (OI) following 48 hours of vecuronium therapy was significantly lower ( p  < 0.0001; 95% confidence interval: 5.9129-9.9671) than mean OI at admission for case group patients. None of the patients receiving vecuronium exhibited neuromuscular deficit during their hospital stay, at time of discharge, or at follow-up evaluation up to 3 months after discharge. In this study, pediatric cases diagnosed with PARDS and managed with mechanical ventilation and vecuronium therapy had improved mean OI following 48 hours of NMBA therapy and a lower mortality when compared with matched control group patients. Incidence of NMBA-related weakness was not commonly observed in these patients.