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Assessment of ambulance services performance by queuing theory, at the Center for Disaster and Emergency Management: A descriptive-analytical study

Mehdi Nasr Isfahani, MD, Azar Niknam, PhD Student, Mahoobeh Doosti-Irani, PhD Student


Background: The emergency departments of the hospitals and emergency medical services (EMSs) centers have a critical role for providing urgent medical care for patients. The statistical data of the present study were provided by the EMS headquarters of the city of Isfahan, from August to November 2017.

Results: The findings showed that on average, 210 missions were accomplished each day by the emergency call center, with an average duration of about 53 minutes, for each mission. In addition, the average time for response time (the time between a call and dispatch of the ambulance) was less than 3 minutes, and the average time for arrival time (the time between request of ambulance and the arrival to the scene) was 8.1 minutes. Adequacy of current number of ambulances and staff is evaluated.

Conclusion: Considering an average of 8.1 minutes for arrival time, we conclude that the EMS of Isfahan is within an acceptable range, compared to the international standards. In fact, it is shown that the infrastructures of EMS system including ambulance fleets, staff, and equipment are sufficient, and as an effective step for reducing the total time of the mission, the EMS has to operate seamlessly with the patient’s admission process in hospitals. Information such as workload hours, availability of resources and staff, etc. ought to be shared between the EMS and the hospital.


emergency medical services, ambulance, queuing theory

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