No role for sodium nitrite in out-of-hospital cardiac arrest

The use of sodium nitrite during active resuscitation by emergency medical services (EMS) was not associated with improved chances of survival to hospital admission or to discharge among patients with out-of-hospital cardiac arrest [1]. It was also not associated with substantial or significant adverse effects on haemodynamics.

As the survival of out-of-hospital cardiac arrest is less than 20% and an animal model has demonstrated increased survival by nearly 50% with the administration of sodium nitrite during resuscitation, Dr Francis Kim (University of Washington, USA) and colleagues investigated whether sodium nitrite given during resuscitation improves outcomes in out-of-hospital cardiac arrest. The study enrolled 1,492 patients who received ether 60 mg sodium nitrite (n=497), 45 mg sodium nitrate (n=499), or placebo (n=496). Patients were aged 18 years and over, had cardiac arrest with life support by paramedics, had intravenous/intraosseous access, and were unconscious. Baseline characteristics were comparable between groups, with an average age of 64 years. The primary endpoints were safety (i.e. survival to hospital admission) and efficacy (i.e. survival to discharge).

Return of spontaneous circulation (ROSC) was seen in 53% of patients who received 45 mg sodium nitrite, 58% of patients who received 60 mg sodium nitrite, and 58% in the placebo group. Re-arrest was observed in 48%, 53%, and 48% per arm, respectively. Survival to admission occurred in 41%, 43%, and 44% per arm, respectively. Survival to discharge for ventricular fibrillation, the secondary endpoint, occurred in 43.2%, 41.3%, and 42.4% of patients, while the rates for survival to discharge for non-ventricular fibrillation were 6.2%, 5.4%, and 6.3%, respectively. Thus, no statistically significant improvement was seen in the primary and secondary outcomes with the use of sodium nitrite (45 mg or 60 mg) compared with placebo during resuscitation in out-of-hospital cardiac arrest. However, sodium nitrite therapy did not result in significant haemodynamic adverse events.

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   1. Kim F, et al. Abstract 406-17. ACC/WCC 28-30 March 2020.

 



Posted on 7 September 202024 February 2021