Assessment of Bronchodilator Response in Children with Asthma Exacerbation Using the Respiratory Resistance Values

Abstract

Sixty-four pediatric patients with asthma exacerbation were studied. The children were subjected to respiratory resistance evaluation using the Airflow Perturbation Device (APD) and spirometry evaluation. They were then administered albuterol and 15 minutes later the APD and spirometry evaluations were repeated. Eleven of the children could not perform spirometry. The APD results demonstrated that respiratory resistance of the patients decreased by about 20%, indicating that the APD could detect the expected response to bronchodilator. However, no similar conclusion could be made with the spirometry parameters (FVC, FEV1, FEV1/FVC, and FEF25% - 75%) performed on the same patients. The differences on the spirometry parameters did not change significantly before and after bronchodilator administration. Furthermore, these differences were negligibly increased or decreased for some with no consistency between the FVC, FEV1, FEV1/FVC, and FEF25% - 75%. Even though all the children were clinically improved after albuterol administration and discharged home, this could not be demonstrated by spirometry data. This study validates previous reports that spirometry is not a reliable pulmonary diagnostic tool for young children, as spirometry is highly effort-dependent and requires a substantial degree of patient cooperation. APD on the other hand is a reliable, simple, effortless diagnostic tool that can be utilized in evaluation and management of children with asthma symptoms and exacerbation.