Clinical Trial of Sodium Nitrite for Out of Hospital Cardiac Arrest (SNOCAT)

In this clinical study, a total of 1500 patients with out-of-hospital cardiac arrest in Seattle/King County will be enrolled. This will be a randomized clinical trial and patients will receive either two different doses of IV sodium nitrite (45 mg or 60 mg) or placebo during resuscitation in the field by paramedics. The primary outcome will be proportion of patients surviving to hospital admission.

The hemodynamic effects of the optimal dose of IV nitrite administered in patients with cardiac arrest are unknown. A significant negative hemodynamic effect from nitrite would decrease the proportion of patients admitted to the hospital, increase rate of re-arrest, or increase the need for vasopressor support in the field. In Seattle/King County, typically 40% of out-of-hospital cardiac arrest patients attended to by paramedics have Return of spontaneous circulation (ROSC) and are admitted to the hospital. In this study, 1500 patients with out-of-hospital cardiac arrest who are undergoing resuscitation by paramedics will be randomized to receive placebo (n=500) or 45 mg IV (n=500) or 60 mg dose (n=500) of sodium nitrite. The study will have 80% power to detect an absolute increase in hospital admission rate of 8% (1-sided .05 level test for each of the two comparisons (45 mg vs placebo and 60 mg vs placebo, no adjustment for multiple comparisons), with a hospital admission rate of 40% in the placebo group and with one interim analysis and stopping only for potential futility and/or harm). The investigators will examine the proportion of patients who survive to discharge as a secondary measure of efficacy. Patients will be eligible for this study if: Intravenous access (IV)/intraosseous access(IO) Cardiac arrest, either Ventricular Fibrillation (VF) or non-VF patients receiving Advanced Cardiac Life Support (ACLS) by Seattle/King County paramedics. Age 18 years or older Comatose Exclusion Criteria Traumatic cause of cardiac arrest Prisoner, pregnancy, age less than 18 (special population/vulnerable population) Known DNAR Drowning as cause of arrest.

45 mg IV of sodium nitrite (n=500) or 60 mg IV sodium nitrite (n=500) given during active resuscitation from out of hospital cardiac arrest.

Inclusion Criteria: Cardiac arrest, either VF or non-VF, patients receiving ACLS by paramedics IV or IO access Comatose Exclusion Criteria: traumatic cause of cardiac arrest prisoner, pregnancy known DNAR

Kim F, Maynard C, Dezfulian C, Sayre M, Kudenchuk P, Rea T, Sampson D, Olsufka M, May S, Nichol G. Effect of Out-of-Hospital Sodium Nitrite on Survival to Hospital Admission After Cardiac Arrest: A Randomized Clinical Trial. JAMA. 2021 Jan 12;325(2):138-145. doi: 10.1001/jama.2020.24326.