Using Sodium Bicarbonate During Prolonged Cardiopulmonary Resuscitation in Prehospital Setting; a Retrospective Cross-sectional Study.

Introduction: Although the 2020 American Heart Association (AHA) guidelines recommend that sodium bicarbonate (SB) be avoided during routine cardiopulmonary resuscitation (CPR) a limited number of studies have examined the effects of SB injection during prolonged CPR (>15 min) in prehospital setting. The present study aimed to examine the effects of prehospital SB use during prolonged CPR on patients' outcome.

Methods: In this retrospective cross-sectional study adult patients aged >18 years who experienced a non-traumatic, out-of-hospital cardiac arrest (OHCA) were compared regarding three outcomes, namely return of spontaneous circulation (ROSC), ROSC > 20 minute, and survival to discharge, based on receiving or not-receiving SB during CPR.

Results: 330 patients were divided into two equal groups of 165. The two groups had similar conditions regarding gender distribution (p = 0.729); mean age (p = 0.741); underlying diseases (p = 0.027); etiology of arrest (p = 0.135); the initial rhythm (p = 0.324); receiving normal saline solution (p = 1.000), epinephrine (p = 0.848), and atropine during CPR (p = 0.054); and using defibrillation (p = 0.324). Those who received SB had 0.80 times greater likelihood for sustained ROSC (adjusted odds ratio (OR) = 0.80, 95% CI: 0.47-1.37, p = 0.415), 0.93 times greater likelihood for ROSC at the scene (adjusted OR = 0.93, 95% CI: 0.55-1.59, p = 0.798), and 0.34 times greater likelihood for survival to discharge (adjusted OR = 0.34, 95% CI: 0.10-1.17, p = 0.087).

Conclusions: The present study demonstrated that prehospital SB use by EMS during prolonged CPR did not improve ROSC rate at the scene, sustained ROSC, and survival to discharge.