Correlation between spirometry and impulse oscillometry in children with asthma.
OBJECTIVE
In certain patients, such as young children or individuals with cerebral palsy or severe mental retardation, it is difficult to perform forced expiratory manoeuvres to measure expiratory flow volume. In such cases, we could evaluate obstructive lung disease through the measurement of airway resistance instead of expiratory flow volume.


METHODS
In this study, we evaluated the correlation of Impulse Oscillometry (IOS) parameters with spirometry values and peak expiratory flow rate (PEFR) measurements to give coherence to IOS recordings in lung function exploration. Total serum IgE levels, total eosinophil counts and specific IgE levels were measured in 48 children with asthma and 66 control subjects, aged 7-15 years of age. IOS, spirometry and PEFR measurements were performed, as well as methacholine challenge. We further analyzed the correlations in atopic asthma, atopic control, nonatopic asthma and nonatopic control groups.


RESULTS
FEV(1) and PEFR showed a significant correlation with impedance and resistance (R) at 5, 10, 20 and 35 Hz, both in atopic asthmatic and in atopic control children. FVC also showed a correlation with impedance and R at 10, 20 and 35 Hz, both in atopic asthmatic and atopic control children. FEF(25-75%) did not show a correlation with resistances.


CONCLUSIONS
FEV(1), FVC and PEFR were significantly correlated with IOS parameters, in both asthmatic and control subjects, especially for atopic children. IOS could be used as a suitable measure of lung function when spirometry and PEF cannot be performed.
Song
Tae Won
TW
Division of Allergy and Respiratory Medicine [corrected] Department of Pediatrics, Ilsan Paik Hospital, Inje University College of Medicine, Goyang-city [corrected] Korea.
Kim
Kyung Won
KW
Kim
Eun Soo
ES
Kim
Kyu-Earn
KE
Sohn
Myung Hyun
MH
D000293:Adolescent; D001249:Asthma / Q000175:diagnosis / Q000503:physiopathology*; D002648:Child; D004804:Eosinophils; D005260:Female; D005540:Forced Expiratory Flow Rates; D005541:Forced Expiratory Volume; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000503:physiopathology; D007073:Immunoglobulin E / Q000097:blood; D008297:Male; D009991:Oscillometry; D013147:Spirometry; D014797:Vital Capacity
D007073:Immunoglobulin E