Description
ABSTRACT
INTRODUCTION
Bronchial Asthma is a chronic inflammatory disorder of the airways leading to considerable morbidity. Spirometry and peak expiratory flow rate (PEFR) are the tools used to assess asthma
where FEV1 (Forced Expiratory Volume in one second) is considered the gold standard.
PEFR is a simpler tool, but has a chance of underestimation or overestimation. We routinely use PEFR in our setting for assessment of asthma. So it was important to investigate further tosee if changes in PEFR can adequately evaluate changes in airway caliber as estimated byFEV1.Hence with the objective to compare pre and post bronchodilator changes in PEFR and FEV1, we conducted this study in asthmatic children.
METHODOLOGY
A descriptive study –diagnostic test evaluation was conducted on 199 asthmatic
children of the age group 7-14years attending Paediatric outpatient clinic, Government
Medical College Ernakulum over 1 year selected by non random sampling method. Peak expiratory flow rate and forced expiratory volume in one second was measured for each subject before and after a bronchodilator and change in the values were expressed as percentages. Bronchodilator reversibility of more than 12 percent was considered significant for both. Sensitivity, specificity, positive& negative predictive value was calculated for change in PEFR & FEV1 with respect to bronchodilator reversibility.
RESULTS & DISCUSSION
In the present study mean values of PEFR and FEV1 was correlating positively (r-0.9). Percent change in PEFR & FEV1 post bronchodilator was having positive correlation(r-0.25). PEFR showed sensitivity of 72% and specificity of 37.9%. Mcnemar test done showed significant results with a p value of 0.017.
CONCLUSION
Our study showed that PEFR had a low specificity in detecting bronchodilator response compared to FEV1 and hence we would conclude that PEFR results have to be correlated with spirometry results while assessing bronchodilator response.
Key words: Bronchial asthma, PEFR, FEV1, Bronchodilator
