Estimated maximum expiratory flow rate, which can assist in predicting severity of asthma exacerbations.
- > 70% → Mild exacerbation
- 40-69% → Moderate exacerbation
- < 40% → Severe exacerbation
According to the American College of Emergency Physicians (ACEP) clinical policy on the use of peak expiratory flow (PEF) in adults with asthma exacerbations, PEF has (1) not been shown to improve outcomes, (2) predict need for admissions, or (3) limit M & M during emergency department management.
Asthma. CDEM. Text
Corbridge TC and Hall JB. The Assessment and Management of Adults with Status Asthmaticus. Am J Resp Crit Care Med. 1995; 151: 1296-1315. Text
McFadden ER et al. Acute bronchial asthma. Relations between clinical and physiologic manifestations. NEJM. 1973; 288(5): 221-5.
Use of Peak Expiratory Flow Rate Monitoring for the Management of Asthma in Adults in the Emergency Department. ACEP Policy Statements. 2007.