Offline exhaled nitric oxide in emergency department and subsequent acute asthma control.

Background: Few studies have evaluated exhaled NO measurement during acute asthma.

Objectives: To evaluate exhaled NO fraction (FE(NO)) and peak expiratory flow (PEF) time-courses during acute asthma treatment (beta 2-agonist plus systemic steroid) and to assess whether FE(NO) time-course predicts subsequent asthma control.

Methods: Sixty-five asthmatic patients (mean +/- SD, 34 +/- 10 years) were prospectively enrolled in three Emergency Departments.