Abstract Body: Background:
Naloxone administration has recently been associated with increased survival to hospital discharge for survivors of out-of-hospital cardiac arrest. However, this study was limited to retrospective data and selection bias. This study aims to determine if Emergency Medical Services (EMS) cardiac arrest protocols have changed related to recommendation of naloxone since recent interest in Narcan for overdose-associated out-of-hospital cardiac arrest (OA-OHCA).

Methods:
We performed a cross-sectional review of statewide EMS protocols (STP) in the United States in 2018 and 2025 as a measure of EMS clinical standards related to naloxone use in OA-OHCA. We evaluated nontraumatic cardiac arrest protocols to determine if there was a change in their recommendation related to the use of naloxone. Protocols were downloaded from each state’s EMS website or, if a protocol was not publicly available, the state medical director was contacted. The institutional review board reviewed this study and deemed it to be exempt.

Results:
A 2025 STP was found for 32/51 (62.7%) states and a 2018 STP was found for 25/51 (49.0%) states. In 2025, 7/32 (21.9%) states recommended the use of naloxone in OA-OHCA in the cardiac arrest protocol. Of these, 3/7 (42.9%) states added this recommendation between 2018 and 2025. Vermont recommended naloxone because “it can be difficult to discern true cardiac arrest from an opioid overdose patient with deep CNS and cardiovascular depression.” Michigan and Nebraska recommended naloxone if opioid overdose is suspected. In 2025, 3/32 (9.4%) states explicitly stated there is no benefit in using naloxone in out-of-hospital cardiac arrest in their cardiac arrest protocol. In non-cardiac arrest protocols, one additional state, New York, recommended naloxone in OHCA in their overdose protocol. Four additional states (Maine, DC, North Dakota, Wisconsin) explicitly stated there is no benefit in using naloxone in out-of-hospital cardiac arrest.

Conclusion:
Three states have altered cardiac arrest protocols since 2018 to recommend naloxone in out-of-hospital cardiac arrest. While this study is limited to statewide protocols, this demonstrates variations in STP recommendations regarding naloxone administration given the weak evidence supporting its use. Limitations include that local and regional protocols are excluded and that STPs may not reflect EMS clinician clinical practice.