Epidemiologic intervention framework of a prehospital emergency medical service

To describe and analyze the characteristics of prehospital medical assistance provided by the Madrid Municipal Emergency and Civil Rescue & Protection Service (SAMUR); and, based on the epidemiologic knowledge so gained, to prioritize public health intervention strategies.

A retrospective cross-sectional analysis of all medical services performed by the SAMUR-Protección Civil in 2001 and 2002. Study variables included causes, response times, hour, day of the week, month, mobile resource, Municipal District, and pathology. For analysis purposes, the relevant data were linked to Access 97 via Open Database Connectivity. Statistical analysis was performed using the SPSS computer software package, with Spearman's correlation coefficient and analysis of variance. Values were deemed statistically significant at p < 0.05.

The study population comprised the 97,937 and 101,438 interventions undertaken in 2001 and 2002, respectively. Mean daily activity in 2002 involved 278 alerts (standard deviation: 46), 95% confidence interval: 273-282. Distributions of the interventions were similar for 2001 and 2002, with peak activity from 1 to 2 pm and 8 to 9 pm, and minimum activity from 6 to 7 am. Activity was at its most intense on Saturdays. The magnitude of the association between the two years by day of the week was 96% (p < 0.001). The Central Municipal District (Centro) triggered 17,875 emergency actions. The prevalent pathology was traumatologic, followed by cardiovascular.

Epidemiologic description enabled the characteristics of the prehospital assistance procedure to be comprehensively ascertained and quantified. False alarms assume special relevance due to their implications. Emergency medical alerts with a psychosocial component are on the increase, something that must be controlled.