Link Between Wildfire Events and Increased Cardiopulmonary Emergency Encounters

Cedars-Sinai Medical Center reported a 24% increase in emergency department encounters for acute pulmonary conditions and a 46% increase for cardiac conditions in the 90 days after the January 2025 Los Angeles wildfires.

The temporal concentration of these visits has immediate implications for emergency capacity, including bed availability, oxygen supply, and triage throughput.

The analysis used a 90-day post-wildfire observation window (Jan 7–Apr 7, 2025) and documented a pattern dominated by respiratory exacerbations—acute asthma flares and COPD exacerbations—and acute coronary syndromes. Compared with baseline seasonal variation in prior years, the post-fire period showed higher relative increases concentrated in fire-affected and adjacent ZIP codes rather than the typical winter respiratory baseline. Monthly encounter volume was stable overall, but the diagnostic mix shifted toward acute cardiopulmonary and systemic presentations, indicating an exposure-linked redistribution of ED diagnostic burden. Older adults and patients with preexisting cardiopulmonary disease and socioeconomic barriers to care faced the highest observed risk of increased acute encounters.

Largest relative increases were seen in acute pulmonary illness and acute myocardial infarction, and there was a striking 118% rise in encounters coded for blood chemistry abnormalities, suggesting more frequent metabolic, renal, or electrolyte derangements alongside respiratory and cardiovascular events. Plausible mechanisms include systemic inflammation and dehydration from smoke exposure, renal strain in susceptible patients, and electrolyte shifts related to acute illness or medication interactions. Heightened diagnostic vigilance for multi-system involvement—basic metabolic panels, renal-function assessment, and targeted electrolyte testing—should accompany respiratory and cardiac evaluations in the post-wildfire period to detect concurrent abnormalities.

Key Takeaways:

• Short-term increase in ED demand for acute pulmonary and cardiac conditions in the 90 days after major wildfires—driven by asthma/COPD exacerbations and acute coronary events.
• Greatest burden was concentrated among residents of fire-affected and adjacent ZIP codes, older adults, and patients with preexisting cardiopulmonary disease or socioeconomic barriers to care.
• Operational priorities include surge staffing, supplemental oxygen and telemetry capacity, and rapid access to medications and basic metabolic testing for high-risk populations.