Study objective: To compare continuously nebulized albuterol with intermittent bolus nebulization of albuterol.
Design: Consecutive block enrollment in groups of ten to continuous or intermittent therapy.
Setting: Urban emergency department.
Type of participants: Patients who presented to the ED with moderate to severe asthma and did not improve after one treatment with nebulized albuterol.
Interventions: All patients received an initial nebulized treatment with 2.5 mg albuterol followed by 125 mg solumedrol. Patients in the intermittent group received 2.5 mg nebulized albuterol at 30, 60, 90, and 120 minutes after the initial treatment. Patients in the continuous group received 10 mg albuterol nebulized in 70 mL over two hours.
Results: There was no difference between groups in age, sex, or initial peak expiratory flow rate (PEFR). Ninety-nine patients were included in the study (47 continuous and 52 intermittent). There was no statistically significant difference in PEFRs or admission rate between groups over the two-hour study period. One subgroup analysis was performed on patients with PEFRs on presentation to the ED of 200 L/min or less. Mean +/- SD baseline PEFR at presentation to the ED was 135 +/- 35 in the 35 patients in the continuous group and 137 +/- 45 in the 34 patients in the intermittent group). At 120 minutes, PEFR was 296 +/- 98 in the continuous group and 244 +/- 81 in the intermittent group (P = .01). Admission: discharge ratios for this subgroup analysis were 11:24 in the continuous group and 19:14 in the intermittent group (P = .03). Mean +/- SD heart rate in the subgroup analysis was 102 +/- 21 at baseline for the continuous group and 109 +/- 22 at baseline in the intermittent group. At 120 minutes, heart rate was 90 +/- 18 in the continuous group and 104 +/- 16 in the intermittent group (P = .002).
Conclusions: Continuous nebulization offers no benefit over intermittent therapy in patients with an initial PEFR of more than 200 L/min. In PEFRs of 200 or less, continuous nebulization may decrease admission rate and improve PEFRs when compared with standard therapy.