Utilization of Neuromuscular Blocking Agents in Acute Brain Injury and Associations with Outcomes: A Post Hoc Analysis of the ENIO Study

Background: Neuromuscular blocking agents (NMBA) have been used in mechanically ventilated patients with moderate-to-severe acute respiratory distress syndrome (ARDS), in cases of clinically significant ventilator dyssynchrony, and in patients with elevated intracranial pressure (ICP). However, practice patterns around NMBA utilization and their impact on outcomes in acute brain injury (ABI) remain insufficiently explored. Methods: This study carried out a post hoc analysis of a multicenter, prospective observational study (NCT03400904) including adult patients with ABI (Glasgow Coma Scale ≤ 12 before intubation) who required invasive mechanical ventilation (IMV) ≥ 24 h. Patients who received NMBA during their first week of ICU stay were propensity matched to those who did not. Results: Propensity score matching was performed in 1482 patients; among the matched cohort (n = 258), 33.3% (n = 86) received NMBA. NMBA utilization varied from 0% to 59.3% across countries. Multivariable regressions demonstrated associations between NMBA use and utilization of intraparenchymal ICP monitoring (odds ratio, OR 2.06; 95% confidence interval, CI 1.16–3.76), extraventricular drain placement (OR 2.18; 95% CI 1.18–4.05), higher PaCO2 values (OR 1.04; 95% CI 1.01–1.09), and moderate-to-severe ARDS (OR 2.40; 95% CI 1.16–5.05). NMBA use was associated with lower hospital mortality (OR 0.35; 95% CI 0.11–0.99) and prolonged IMV duration (OR 1.56; 95% CI 1.38–1.76), but not with reintubation rates or tracheostomy placement. Conclusions: NMBA utilization varied widely, highlighting the need for more evidence to guide clinical practice. NMBA were most commonly used in patients with ICP monitoring or moderate-to-severe ARDS; associations with outcomes warrant further exploration in randomized controlled trials.