Modeling an emergency medical services system using computer simulation.
OBJECTIVE
In the emergency medical services (EMS) system, appropriate prehospital care can substantially decrease casualty mortality and morbidity. This study designed a simulation model, evaluated the existing EMS system, and suggested improvements.


METHODS
The study focused on 23 networked EMS hospitals affiliated with 36 emergency response units (subgroups) to perform two-tier rescues (advanced life support [ALS] in addition to basic life support [BLS] services) in Taipei, Taiwan. Using the existing EMS model as a base, this research constructed a computer simulation model and explored several model alternatives to achieve the study's objectives. The virtual models varied with staffing level, number of assigned emergency network hospitals, and various two-tier rescue probabilities.


RESULTS
Increasing the staffing to two teams for Hospital 22 lessened the call waiting probability (delay between rescue call and ambulance dispatch) by 50%, even if the dispatch rate of the two-tier rescue increased from the empirical 2% to a simulated 10 and 20%. Changing the two-tier rescue pattern so each EMS subgroup cooperated with two specific, preassigned network hospitals lowered the probability of patients having to wait for rescue dispatch to under 1%.


CONCLUSIONS
The following alternatives provided the greatest combination of effectiveness, quality patient care, and cost-efficiency: (1) because of its unique location, increase Hospital 22's staffing level to two ALS teams. (2) Establish a specific rescue protocol for the two-tier system that preassigns two network hospitals to each of the 36 EMS subgroups along with a prearranged calling sequence. If implemented, this will improve EMS performance, streamline the system, reduce randomness, and enhance efficiency.
Su
Syi
S
Institute of Health Care Organization Administration, School of Public Health, National Taiwan University, No. 1, Sec. 1, Jen Ai Road, Rm. 1512, 100, ROC, Taipei, Taiwan. susyi@ha.mc.ntu.edu.tw
Shih
Chung-Liang
CL
D003198:Computer Simulation; D017598:Efficiency, Organizational / Q000706:statistics & numerical data*; D004632:Emergency Medical Services / Q000458:organization & administration*; D017146:Models, Organizational; D013624:Taiwan