Los Angeles County Pandemic Flu Hospital Planning Model

Brief Description
Growing concern over acute, unpredictable public health emergencies have led to disaster planning at the local healthcare service and governmental levels. Unexpected shocks to hospital systems, like a pandemic flu, may cause temporary surges in demand for hospital care in excess of current supply. However, quantifying the number of patients who will not receive care due to the expected overwhelming need for hospital services has been absent from many preparedness efforts. To meet this need, a Pandemic Flu Hospital Planning Model (the Model) was developed and tested in the Los Angeles (LA) County hospital market.

The Model simulates inpatient and emergency department (ED) care at more than 100 LA County hospitals. Since these hospitals are interconnected, a systems approach is taken allowing patients to move between hospitals to more accurately capture true patient traffic. In this project two potential 25 week flu pandemics are considered: moderate (25% of population becomes ill) and severe (35% of the population becomes ill). Three policies were modeled to determine the impact of hospital intervention on reducing the number of patients who cannot receive hospital care due to overwhelming demand. These policies were: reduce elective admissions, increase acute respiratory support bed supply, and ignore insurance status. Model outputs are divided into those estimating numbers of patients who receive care and those who do not (unmet need). Outputs related to the receipt of hospital care include: numbers of ED visits, inpatient admissions through the ED, inpatient occupancy rates, and numbers of admitted patients requiring ventilation. Variables detailing unmet need include numbers of ED and unscheduled patients needing inpatient beds when none are available and numbers of ED patients who leave the ED without being treated.

During a moderate flu pandemic over 100,000 patients arrive at LA hospital emergency departments requiring care. This number is 300,000 for a severe flu pandemic. If no policies are implemented, 44,000 patients during a moderate flu and 180,000 patients during a severe flu will be unable to receive the care they need due to congestion in the hospital system and insufficient hospital supply. Intervening with all three policy options yields a 15% reduction in unmet need.

Policy Implications
The model finds hospital interventions alone are insufficient; many patients needing care are unable to receive it. To reduce the demand for hospital services and improve the efficacy of limited hospital resources during a pandemic, targeted, early, and aggressive treatment in the community should be explored. Other regional hospital markets could benefit from more efforts to simulate patient flow through an interconnected system of services to plan for a variety of shocks besides a flu pandemic including hospital closures and other disasters such as floods and earthquakes.

Funding for this program was generously provided by the Los Angeles County Department of Public Health

Key Partners
The Los Angeles County Departments of Public Health and Health Services, Hospital Association of Southern California, Harbor-UCLA Medical Center, Kaiser Permanente, Providence Health and Services, City of Hope Medical Center, and Children’s Hospital Los Angeles.

Andrew Barnes, Phone: 213-538-0707, Email: abarnes@nhfca.org