Incidence of agonal respirations in sudden cardiac arrest

Abstract

Study objective: To discover the frequency of agonal respirations in cardiac arrest calls, the ways callers describe them, and discharge rates associated with agonal respirations.

Design: We reviewed taped recordings of calls reporting cardiac arrests and emergency medical technician and paramedic incident reports for 1991. Arrests after arrival of emergency medical services were excluded.

Setting: King County, Washington, excluding the city of Seattle.

Participants: Four hundred forty-five persons with out-of-hospital cardiac arrests receiving emergency medical services.

Interventions: Telephone CPR, emergency medical technicians-defibrillation, and advanced life support by paramedics.

Measurements and main results: Any attempts at breathing described by callers were identified, as well as whether agonal respirations could be heard by dispatcher, emergency medical technicians, or paramedics. Agonal respirations occurred in 40% of 445 out-of-hospital cardiac arrests. Callers described agonal breathing in a variety of ways. Agonal respirations were present in 46% of arrests caused by cardiac etiology compared with 32% in other etiologies (P < .01). Fifty-five percent of witnessed arrests had agonal activity compared with 16% of unwitnessed arrests (P < .001). Agonal respirations occurred in 56% of arrests with a rhythm of ventricular fibrillation compared with 34% of cases with a nonventricular fibrillation rhythm (P < .001). Twenty-seven percent of patients with agonal respirations were discharged alive compared with 9% without them (P < .001).

Conclusion: There is a high incidence of agonal activity associated with out-of-hospital cardiac arrest. Presence of agonal respirations is associated with increased survival. These findings have implications for public CPR training programs and emergency dispatcher telephone CPR programs.