Impact of Airway Management and Initial Blood Gas Analysis on Clinical Outcomes after Out-of-Hospital Cardiac Arrest: A National Observational Study

Introduction High-quality CPR guideline were well consent, whereas optimal prehospital airway management method is debating. Endotracheal intubation (ETI) were regarded as the standard airway management during OHCA. Previous studies did not verify that prehospital ETI provide favorable clinical outcomes than supraglottic airway (SGA) or bag valve mask (BVM). The aim of this study was to determine the effect of prehospital airway management method on outcomes and compare the effect size across the initial blood gas analysis and lactate level on outcomes after OHCA Material & Method This study was a retrospective and population based observational study utilizing the Korean Cardiac Arrest Research Consortium (KoCARC) database, which includes all adult EMS-treated OHCA patients with presumed medical etiology. The principal component analysis using pH, pCO2, pO2 and serum lactate was conducted, producing Prin1. The cut-off values of pH, pCO2, pO2, serum lactate and Prin1 for prediction of favorable neurological outcomes were calculated using a receiver operating characteristics (ROCs) curve and area under the ROC curve (AUC). Adjusted ORs (AORs) with 95% confidence intervals (CIs) were calculated via multivariable logistic regression analysis to assess the interaction effects of airway management method on initial laboratory data of OHCA patients. Result During study period, SGA was preferred than ETI (52.1% vs 7.64%, P<.001). Initial laboratory data shows that SGA group had higher pH, pCO2 values than ETI or BVM but no significant difference of pO2 and lactate. There was no significant interaction between prehospital ROSC, survival to discharge and good neurological recovery on airway management according to laboratory data and Prin1 cut-off values. Conclusion In this nationwide population-based observational study, we observed that there was no significant interaction effect between airway management and laboratory data in aspect of prehospital ROSC rate, survival to discharge rate and favorable neurological outcomes. We would propose that SGA consider initial prehospital airway management in basic to intermediate level EMS system.