44 Do organisational change in out-of-hour service influence on the use of helicopter emergency medical service? an observational study of a natural experiment

Aim Over the last decades out-of-hour services in Norway have been centralised to cover lager geographical areas, resulting in longer response times for the on-call GP. Reports indicate an unintended increase in requests of helicopter emergency medical services (HEMS) as a result. We aimed to investigate alteration in the requests for HEMS and NACA-score of the patients transported. Method In 2009 nine municipalities in the county of Sogn og Fjordane relocated all local out-of-hour services into one large casualty clinic (SYS-IKL). We included all primary HEMS requests in the county from 2004–2013 and compared missions within the area of SYS-IKL to missions in the rest of the county. Results Preliminary data included 7310 requests. Within SYS-IKL requests were 4.4 per week in the period. Completed and cancelled requests were 3.0 and 1.3 per week before 2009 compared to 2.7 and 1.6 per week after 2009. Outside SYS-IKL requests were 8.9 per week before 2009 and 10.4 per week after 2009. Completed and cancelled requests were 5.1 and 3.4 per week before 2009 compared to 5.5 and 4.6 per week after 2009. Mean NACA-score within SYS-IKL was 3.98 and 3.87 (p=0.115) compared to 3.78 and 3.77 (p=0,786) outside SYS-IKL before and after 2009, respectively. Conclusion Preliminary results did not confirm the hypothesised increase in use of HEMS or reduced NACA-score due to centralization of out-of-hour services. However, further statistical analyses are required. Conflict of interest None Funding Norwegian Air Ambulance Foundation.