Peak Expiratory flow Rate for Emergency Department Management of Acute Asthma Exacerbation: A Randomized Controlled Trial Pilot Study.

BACKGROUND Peak expiratory flow rate (PEFR) is used to assess asthma severity, and guidelines recommend serial PEFR measurements to guide management. However, the evidence behind this practice is limited.

OBJECTIVES To compare outcomes between PEFR-guided and non-PEFR-guided emergency department (ED) care for acute asthma exacerbations.

METHODS This randomized, unblinded, two-arm study compared PEFR-guided therapy with symptom-guided therapy in ED patients aged 16 to 55 years presenting with acute asthma without chronic obstructive pulmonary disease (COPD). Patients were enrolled within 15 min of their first nebulizer treatment. PEFR was measured at baseline and every 30 min until symptom resolution, discharge, or admission. Clinicians in the PEFR-guided group received PEFR values with guideline-based recommendations, while clinicians in the non-PEFR-guided group were blinded to PEFR values. The primary outcome was the proportion of patients with none or mild asthma symptoms by 150 min after enrollment. The secondary outcome was hospitalization.

RESULTS A total of 210 patients were enrolled (101 PEFR-guided; 109 non-PEFR-guided). Symptom control by 150 min occurred in 73 (72%) vs. 78 (72%) patients (95% CI, -11% to 13%). Hospitalization was similar: 17 (17%) in the PEFR group vs. 13 (12%) in the non-PEFR group (95% CI, -5% to 14%). Subgroup hospitalization results by percent-predicted PEFR were comparable. There was no difference in nebulized medication use.

CONCLUSION In this randomized trial, PEFR-guided care did not improve symptom control, reduce resource utilization, or affect disposition compared with symptom-guided care. These findings suggest limited benefit of PEFR use in ED asthma management. Larger, multicenter studies are needed before informing practice changes.