Trends from the field: Real-time EMS surveillance

Background: Over ten years ago a real-time EMS surveillance system was implemented in a large metropolitan area with population of 3.1 million and 15 million annual overnight tourists. Originally designed to monitor flu outbreaks, this system has proven useful to provide day-to-day continuous situational awareness, identify public health events, and has enabled timely and appropriate EMS responses. This system provided necessary data for public health professionals to trend local 9-1-1 utilization and direct system planning. Methods: Prehospital activity is monitored using a county-wide real-time electronic system. Initially data collected included 42 medical complaints but with implementation of NEMSIS compliant data set this increased to 72 paramedic provider impressions. Additional monitored data includes cause of injury, outcome, location, interventions, and hospital diagnosis. Data are compared weekly, monthly and annually. Standard thresholds based on statistically significant variations are established annually to trigger further investigation. Results: EMS surveillance has prompted numerous investigations. It is integral to the County's Excessive Heat Response Plan designed to warn/protect the public during heat emergencies through monitoring heat related patient complaints. Surveillance also identified increases in Psychiatric/Disturbance in Behavior complaints (185% over 10 years). This led to collaboration between law enforcement and prehospital to provide more effective and safe service delivery. Conclusions: EMS surveillance has become a vital tool for Public Health and Safety. With over ten years of data, understanding of how local 9-1-1 emergency medical services are utilized has led to improvements in many aspects including allocation of resources, protocols/policies, provider education and community health promotion.