Timely transport of a patient to a capable medical facility is a key factor in providing quality care for trauma patients. This paper presents a mathematical model and a related solution method to search for optimal locations of trauma centers and air ambulances. The complicatedness of this problem stems from the characteristic that optimal locations for the two resources are coupled with each other. Specifically, this coupling makes it difficult to develop  a priori  estimates for the air ambulance's busy fraction, which are required to construct a probabilistic location model. We propose a method that uses integer programming and simulation to iteratively update busy fraction parameters in the model. Experimental results show that the proposed method is valid and improves the solution quality compared to alternative methods. We use real data on Korean trauma cases, and apply the method to the design of a trauma care system in Korea.
['Taesik Lee', 'Hoon Jang', 'Soo-Haeng Cho', 'John Turner']
A simulation-based iterative method for a trauma center: air ambulance location problem