Continuous neuromuscular blockade is associated with decreased mortality in post-cardiac arrest patients

Aim: Neuromuscular blockade may improve outcomes in patients with acute respiratory distress syndrome. In post-cardiac arrest patients receiving therapeutic hypothermia, neuromuscular blockade is often used to prevent shivering. Our objective was to determine whether neuromuscular blockade is associated with improved outcomes after out-of-hospital cardiac arrest.

Methods: A post hoc analysis of a prospective observational study of comatose adult (>18 years) out-of-hospital cardiac arrest at 4 tertiary cardiac arrest centers. The primary exposure of interest was neuromuscular blockade for 24h following return of spontaneous circulation and primary outcomes were in-hospital survival and functional status at hospital discharge. Secondary outcomes were evolution of oxygenation (PaO2:FiO2), and change in lactate. We tested the primary outcomes of in-hospital survival and neurologically intact survival with multivariable logistic regression. Secondary outcomes were tested with multivariable linear mixed-models.

Results: A total of 111 patients were analyzed. In patients with 24h of sustained neuromuscular blockade, the crude survival rate was 14/18 (78%) compared to 38/93 (41%) in patients without sustained neuromuscular blockade (p=0.004). After multivariable adjustment, neuromuscular blockade was associated with survival (adjusted OR: 7.23, 95% CI: 1.56-33.38). There was a trend toward improved functional outcome with neuromuscular blockade (50% versus 28%; p=0.07). Sustained neuromuscular blockade was associated with improved lactate clearance (adjusted p=0.01).

Conclusions: We found that early neuromuscular blockade for a 24-h period is associated with an increased probability of survival. Secondarily, we found that early, sustained neuromuscular blockade is associated with improved lactate clearance.