Clinical paper Sodium bicarbonate administration is associated with improved survival in asystolic and PEA Out-of-Hospital cardiac arrest

Background: Sodium bicarbonate ("bicarb") administration in out-of-hospital cardiac arrest (OHCA) is intended to counteract acidosis, although there is limited clinical evidence to support its routine administration. We sought to analyze the association of bicarb with resuscitation outcomes Methods: Records were obtained from the 2019-2020 ESO Data Collaborative prehospital electronic health record database, spanning 1,322 agencies in 50 states. OHCAs with resuscitations lasting 5-40 minutes were stratified by presenting ECG rhythm (VF/VT, pulseless electrical activity (PEA), asystole) for analysis. The outcomes of any prehospital ROSC and survival to discharge were compared by bicarb status using propensity score matching and logistic regressions with/without adjustment. Results: We analyzed 23,567 records, 6,663 (28.3 %) of which included bicarb administration. Most patients presented in asystole (67.4 %), followed by PEA (16.6 %), and VF/VT (15.1 %). In the propensity-matched cohort, ROSC was higher in the bicarb group for the asystole group (bicarb 10.6 % vs control 8.8 %; p = 0.013), without differences in the PEA or VF/VT groups. Survival was higher in the bicarb group for asystole (bicarb 3.3 % vs control 2.4 %; p = 0.020) and for PEA (bicarb 8.1 % vs control 5.4 %; p = 0.034), without differences in the VF/VT group. These results were consistent across adjusted/unadjusted logistic regression analyses: bicarb was associated with ROSC and survival in asystole [uOR (95 % CI): ROSC 1.23 (1.04-1.44), survival 1.40 (1.05-1.87)] and with survival in PEA (1.54 (1.03-2.31). Conclusions: Bicarb was associated with survival in non-shockable rhythms and ROSC in asystole. Findings from this observational study should be corroborated with prospective randomized work.