Modeling the Consequences of Major Incidents for Health Care Systems Gary B. Hirsch 22nd International Conference of the System Dynamics Society Oxford July 27, 2004

Background and Purpose Part of larger effort involving 3 national labs in the US Model health care at metropolitan, regional, and national levels and in the context of 13 other infrastructures Help officials and their communities understand impact of different types of incidents on the health care system and its capacity to care for patients assess different strategies for dealing with incidents and scale needed to respond effectively determine capacity of backup resources and stockpiles for supporting local health care systems develop shared understanding among different levels of government, various services, and areas that depend on each other for mutual aid

Threats to Health Care Systems Direct Attack Infrastructure Failure Overwhelming Demand Combined Threats Different profiles with regard to impact over time, extent of health care demand, reduction in health system capacity

Emphases Suggested by the Literature “All hazards” approach--planning for a wide range of contingencies Continuation of “normal” health services while responding to major incidents Plan for entire health system, not just hospitals Capacity to deal with entire (exposed) population, not just the severely injured Modeling that had been done was mostly special purpose--e.g., bio-terror attacks

System Overview

Population Flows as a Result of an Incident

Health Care System Detail: Hospital Inpatients

Events That Can Be Simulated Infrastructure Failures Limited Duration Events Natural Disasters Explosions, Fires Spread of a Pathogen, with or without contagion Combined Events

Infrastructure Failure Emergency Patients Awaiting Admission to the Hospital Emergency Patients Awaiting Admission Chronic Patients Requiring Admission

Infrastructure Failure (Cont’d) Fully Functional Population Cumulative Deaths

Infrastructure Failure (Cont’d) Emergency Patients Awaiting Admission (with 200 bed self-contained field hospital in blue)

Limited Duration 2000 Casualty Event--Sensitivity Test with More Severe Casualties Emergency Patients Awaiting Admission Inpatient Length of Stay (Hours)

Contagious Disease--with and without Large Scale Prophylaxis Cumulative Deaths Fully Functional Population

Contagious Disease--with and without Large Scale Prophylaxis (cont’d) Emergency Patients Awaiting Admission Staffed Beds Available

Further Development Improve Data, Based on Case Studies If Possible Expand to Assure Model Covers a Wide Range of Scenarios Link to Other Infrastructure Models Apply to Real-World Communities Create Management Simulator and Use as Basis for Workshops Bringing Together Multiple Jurisdictions and Disciplines