Out-of-Hospital Presentation and Management of Asthma and Chronic Obstructive Pulmonary Disease Exacerbations in the United States: A Nationwide Retrospective Cohort Study

Ann Emerg Med. 2023 Jun;81(6):679-690. doi: 10.1016/j.annemergmed.2022.10.013. Epub 2023 Jan 18.


Study objective: To describe the demographic, clinical, and emergency medical service (EMS) response characteristics associated with EMS activations for asthma and chronic obstructive pulmonary disease (COPD) exacerbations in the US.

Methods: Using a nationwide set of out-of-hospital patient care report data from 2018 to 2019, we analyzed 9-1-1 EMS activations where asthma/COPD exacerbation was indicated by symptom, impression, or treatment provided. We excluded patients with ages less than 2 years or unknown, nonemergency transports, and encounters with any indication of anaphylaxis. Demographic, clinical, and EMS response characteristics were described for pediatric and adult patients with asthma/COPD exacerbations.

Results: A total of 1,336,988 asthma/COPD exacerbations were included, comprising 5% of qualifying 9-1-1 scene activations from 2018 to 2019. Most patients were adults (96%). Most adult patients were female (55%), whereas most pediatric patients were male (58%). Most activations occurred in urban settings (82%), particularly in pediatric patients (90%). Most asthma/COPD exacerbations were managed by advanced life support units (94%). Inhaled bronchodilators and systemic corticosteroid therapy were administered to 75% and 14% of all patients, respectively. Adults more often had oxygen saturation <92% (43% vs 20% of pediatric patients) and were more often treated with assisted ventilation (9% vs 1%).

Conclusion: In this large nationwide sample of 9-1-1 activations treated and transported by EMS, 5% were for asthma/COPD exacerbation. Future work should focus on evidence-based standardization of EMS protocols and practice for asthma/COPD exacerbations to improve the quality of EMS care.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asthma* / diagnosis
  • Asthma* / epidemiology
  • Asthma* / therapy
  • Bronchodilator Agents / therapeutic use
  • Child
  • Disease Progression
  • Female
  • Hospitals
  • Humans
  • Male
  • Pulmonary Disease, Chronic Obstructive* / diagnosis
  • Pulmonary Disease, Chronic Obstructive* / epidemiology
  • Pulmonary Disease, Chronic Obstructive* / therapy
  • Retrospective Studies
  • United States / epidemiology


  • Bronchodilator Agents