Resource Allocation Policies for Minimizing Mortality in Mass Casualty Events‏ Dr. Izack Cohen Prof. Avishai Mandelbaum, Noa Zychlinski MSc. The Faculty of Industrial Engineering and Management The Technion – Israel institution of Technology

Oklahoma City, 1995 Madrid, 2004 Argentina, 1994 NYC, 2001 London, 2005 Turkey, Rio De Janeiro, 2011 Indian Ocean, 2004 Japan, 2011

The Main Results A general, fluid-model based approach, for modeling MCEs. An MCE classification scheme,wherein a resource allocation policy is suggested for each class. A real-time management approach. 3

4 Flow of Casualties through an ED during an MCE

Casualties Flow in a Two-Station Network 5 To immediate operation Arriving Immediates Mortality To admission and ICU (1) Shock Rooms (2) Operation Rooms To admission and ICU Mortality

Optimization Problem 6 Mortality Rate Casualties at Station Minimizing Mortality Arrival Rate Treatment Rate Surgeons at Station Change in Casualties Casualties at Station Balance Equation for Station 1 Balance Equation for Station 2 Resource Constraint

Solving the Optimization Problem 7

From Solutions to Policies 8 Conditions Station 1 or 2 – equal performance (Case 1) Station 1 (Case 4) Station 2 (Case 7) Station 1 (Case 2) Station 1 (Case 5) Prioritize Station 1 and switch priorities at some t (Case 8) Station 2 (Case 3) Prioritize Station 2 and switch priorities at some t (Case 6) Station 2 (Case 9)

9 Policies Application A dynamic allocation of surgeons to two treatment stations, life-saving followed by operating, so as to minimize mortality during an MCE. (a) Represents an event that took place far from the hospital, hence the arrival waves are 60 minutes apart and (b) represents an event at closer proximity where the arrival waves are 15 minutes apart. (a) (b)

10 Optimal resource allocation solutions for different time points 0, 60, 120, 180 MCE Real-Time Management

11 Summary Traditional MCE models are based on simulation experiments. We used fluid models to formulate the problem and then gained structural results. The suggested optimal allocation policies can be easily applied to prepare an emergency plan for reference scenarios. A developed rolling horizon approach allows for real- time management of MCEs.

12 Prof. Avishai Mandelbaum, Mrs. Noa Zychlinski – co-authors Dr. Michalson Moshe, Medical Director of Trauma teaching center, Rambam Hospital Dr. Israelit Shlomi, Chief of ED, Rambam Hospital