Cardiac arrests in general practice clinics or witnessed by emergency medical services: a 20-year retrospective study

Objective: To compare the frequency and outcomes of cardiac arrests in general practice clinics with those of paramedic-witnessed cardiac arrests. Design, setting: Retrospective study; analysis of Victorian Ambulance Cardiac Arrest Registry data, 1 January 2000 – 30 December 2019. Participants: Patients with non-traumatic cardiac arrests whom emergency medical services staff attempted to resuscitate. Main outcome measures: Survival to hospital discharge. Results: 6363 cases of cardiac arrest were identified: 216 in general practice clinics (3.4%) and 6147 witnessed by paramedics (96.6%). The proportion of patients presenting with initial shockable rhythms was larger in clinic (126 patients, 58.3%) than paramedic-witnessed cases (1929, 31.4%). The proportion of general practice clinic cases in which defibrillation was provided in the clinic increased from 2 of 37 in 2000–2003 (5%) to 19 of 57 patients in 2016–2019 (33%); survival increased from 7 of 37 (19%) to 23 of 57 patients (40%). For patients with initial shockable rhythms, 57 of 126 in clinic cases (45%) and 1221 of 1929 people in paramedic-witnessed cases (63.3%) survived to hospital discharge; of 47 general practice patients defibrillated by clinic staff, 27 survived (57%). For patients with initial shockable rhythms, the odds of survival were greater following paramedic-witnessed events (adjusted odds ratio [aOR], 3.39; 95% CI, 2.08–5.54) or general clinic arrests with defibrillation by clinic staff (aOR, 2.23; 95% CI, 1.03–4.83) than for general practice clinic arrests in which arriving paramedics provided defibrillation. Conclusion: Emergency medical services should be alerted as soon as possible after people experience heart attack warning symptoms. Automated external defibrillators should be standard equipment in general practice clinics, enabling prompt defibrillation, which may substantially reduce the risk of death for people in cardiac arrest.