Seizure-like presentation in OHCA creates barriers to dispatch recognition of cardiac arrest.

Purpose: Early recognition of out-of-hospital cardiac arrest (OHCA) by 9-1-1 dispatchers is a critical first step along the resuscitation pathway. Barriers to recognition may lead to adverse outcomes among patients. This study aims to determine the impact of seizure-like activity among OHCA patients during 9-1-1 calls.

Methods: We evaluated a retrospective cohort study of all adult, non-traumatic OHCAs that occurred prior to emergency medical services (EMS) arrival on scene in a major metropolitan area from 2014-2018. Dispatch recordings were reviewed to determine if seizure-like activity was reported by the caller using key descriptor phrases such as "seizing," "shaking," or "convulsing." We compared patient demographics, arrest factors, and hospital outcomes using a regional OHCA quality improvement database.

Results: Among 3502 OHCAs meeting our inclusion criteria, 149 (4.3%) contained seizure-like activity. When compared to patients without seizure-like activity (3353; 95.7%), patients presenting with seizure-like activity were younger (54 vs. 66 years old; p < 0.05), had a witnessed arrest (88% vs 45%; p < 0.05), presented with an initial shockable rhythm (52% vs. 24%; p < 0.05), and survived to hospital discharge (44% vs. 16%; p < 0.05). The seizure-like activity group also had a longer median time to dispatcher identification of the cardiac arrest [130 s (72,193) vs 62 s (43,102); p < 0.05].

Conclusions: Reported seizure-like activity among patients in cardiac arrest poses a barrier to recognition of cardiac arrests by dispatchers leading to delays in resuscitation instructions.