Out-of-hospital cardiac arrests in an urban/rural area during 1991 and 1996: have emergency medical service changes improved outcome?

Survival after out-of-hospital cardiac arrest is influenced by pre-hospital emergency medical care. This study compares outcome of cardiac arrest victims presenting to an emergency department serving a mixed urban/rural area (Norfolk, UK) in 1991 with 1996. Between these years the regional emergency medical service (EMS) was extensively re-organized. We identified 113 such cases of out-of-hospital cardiac arrest in 1991 and 147 in 1996. The age distribution, proportion of witnessed arrests, and initial rhythms were similar for the 2 years. In 1996 EMS response time was significantly slower and the proportion of cases where the EMS arrived before arrest was significantly lower. Fewer patients who had a witnessed arrest received immediate bystander CPR in 1996. The number of patients discharged home decreased from 15 in 1991 to 11 in 1996, but this difference did not reach statistical significance. The majority of survivors had restoration of spontaneous circulation prior to arrival in the emergency department (14 in 1991 and ten in 1996). Survival was greatest in those arresting in the presence of the EMS (ten in 1991 and nine in 1996). In conclusion changes in EMS provision have resulted in an increase in the response time. This was associated with a decrease in the number of survivors although this was not statistically significant.