Automated external defibrillators (AEDs) from community first responder systems (CFR-system) are important to achieve early defibrillation in out-of-hospital cardiac arrest (OHCA). It is unclear how far community first responders (CFR) can travel to fetch and connect an AED to achieve this goal. This study aims to evaluate the relation of the distance between OHCA and the dispatched CFR-system AED and speed of AED-connection. Within the Dutch prospective ARREST registry, OHCA patients from 2016 to 2021 with a connected CFR AED were identified. The location of each connected AED was retrieved. Straight-line distances between patient and AED-location were calculated using Google Maps. Time intervals between emergency-call and AED-connection were compared according to straight-line distances and degree of urbanization. Out of 3231 OHCAs with the CFR-system activated, 2037 (63%) patients had an AED connected before emergency medical services arrival, of which 426 by a CFR. Exact AED-locations were known in 387 OHCA (study population). Overall, the AEDs connected by a CFR where located within 949m straight-line distance of the OHCA. AEDs connected within 6, 8, or 10min of the emergency-call, were located within 506m, 796m and 838m straight-line distance, respectively. In 44% of these cases, the CFR connected an AED to which he/she was not referred to, but taken from another address, which significantly impacted the maximal distance covered: 773m for CFR-system referred AEDs versus 1126m for not CFR-system referred (p=0.001). To facilitate early AED-connection (≤6min), any address should have a CFR-system AED located within approx. 500m.

Perioperative cardiac arrest (PO-CA) is a rare but critical event. The impact of surgical timing, i.e. whether procedures are conducted during office hours or out-of-hours, on its occurrence remains unknown. We aimed to outline the incidence and mortality of PO-CA in Sweden, and assess whether surgical timing influences the risk of PO-CA in non-cardiothoracic, non-obstetric emergency surgery. We conducted a retrospective cohort study of adult patients (≥18 years) in the Swedish Perioperative Register between 2019 and 2023. We examined the incidence and mortality of PO-CA, defined as cardiac arrest in the operating theatre or post-anaesthesia care unit (PACU). In a subset of non-cardiothoracic, non-obstetric emergency surgery, we estimated the odds of PO-CA in procedures commenced out of hours compared with during office hours, adjusting for sex, age, comorbidities, ASA class, and case urgency, using mixed-effects logistic regression. Among 1,568,877 procedures, PO-CA occurred in 395 cases (314 in the operating theatre, 81 in the PACU), corresponding to a crude incidence of 2.5/10,000 procedures, with a subsequent 30-day mortality of 42.5 %. In non-cardiothoracic, non-obstetric emergency surgery, the crude odds ratio for PO-CA out of hours vs. office hours was 1.31 (95 % CI 1.00-1.70), while the adjusted odds ratio was 1.13 (95 % CI 0.86-1.48). In this nationwide study, PO-CA was rare, with over half of affected patients surviving beyond 30 days. Although crude incidence appeared higher out of hours in non-cardiothoracic, non-obstetric emergency surgery, this pattern likely reflects greater patient complexity rather than out-of-hours circumstances per se.