Abstract Sa102: Does Benefit of An Advanced Airway Depend on Initial Rhythm? A Secondary Analysis of the Pragmatic Airway Resuscitation Trial

Background: About 80 percent of patients with out-of-hospital cardiac arrest (OHCA) present with a non-shockable initial rhythm (asystole or pulseless electrical activity (PEA)), which is associated with lower survival. Advanced airway management and oxygen delivery are important OHCA interventions, but their impact based on different presenting rhythm groups are unknown. Our objective was to determine if advanced airway strategy is associated with outcomes in shockable, PEA and asystolic OHCA. Methods: We performed a secondary analysis of data collected from the Pragmatic Airway Resuscitation Trial (PART), which assigned adult OHCA to a strategy of either endotracheal intubation (ETI) or laryngeal tube (LT) for initial airway management. We stratified patients by initial cardiac rhythm: shockable (ventricular fibrillation/tachycardia, AED shock), PEA or asystole. We excluded AED non-shockable and unknown rhythms. The primary outcome was 72-hour survival. Secondary outcomes included return of spontaneous circulation (ROSC) at emergency department arrival, survival to hospital discharge, and survival with good neurological function (modified Rankin score ≤3). We used general estimating equations to determine the associations between airway strategy and outcomes, stratified by initial rhythm and adjusted for age, sex, witnessed status, and bystander CPR. Results: There were 3,004 patients in the parent trial of which 2,847 were included in this analysis. Of these 575 were shockable, 671 were PEA, and 1,601 were asystole. Compared with ETI, LT airway was not associated with improved 72-hour survival in shockable rhythms (OR adj 1.30 (0.91-1.67)), PEA (OR adj 0.97 (0.65-1.45)), or asystole (OR adj 1.13 (0.79-1.64)). Similarly, we noted no significant difference by airway strategy for secondary outcomes of ROSC, survival to discharge, and survival to discharge with good neurological function. Conclusion: Prehospital advanced airway management strategy (ETI vs. LT) was not significantly associated with outcomes regardless of initial rhythm.