This is a prospective, randomized, double blinded, controlled study. The patients will be randomly assigned to one of the treatment groups (experimental or control groups).
The patients will be assessed 1 hour later and every 30 minutes thereafter until discharge. Following 4 hours in the emergency room, any patient who do not meet the discharge criteria (PRAM score ≤ 3 and SpO2 ≥ 92%) will be admitted to the hospital. Each patient's attending physician will determine the need for additional therapies following the first hour.
Identification of respiratory viruses in the nasal lavage samples wil be performed using the CLART PneumoVir® kit.
Albuterol plasmatic levels will be analyzed via HPLC (High Performance Liquid Chromatography).
To genotype the ADBR2 receptor (blood samples), the gene regions encompassing the Arg16Gly, Gln27Glu, and Arg19Cys Thr164Ile polymorphisms will be amplified via PCR. The resultant amplimers were then sequenced.
A sample of 124 patients (62 in each group) was calculated to provide an 80% power with which to detect a significant difference of at least 30 minutes in the lengths of stay between the groups. The chi-square test will be used to compare hospital admission rates and tremor rates. For all other outcomes, t-tests for mean comparisons (variables with a normal distribution), a Mann Whitney test (nonparametric data) and ANOVA with repeated measures will be used.
