Lung function measurements in children - copsac
Lung function measurements in children - copsac
Lung function measurements in children - copsac
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Acute severe wheezy exacerbations<br />
Acute severe wheezy exacerbations was def<strong>in</strong>ed as an acute obstructive respiratory<br />
illness diagnosed by the COPSAC cl<strong>in</strong>ical research unit doctor and judged to be a<br />
severity requir<strong>in</strong>g treatment with oral or high-dose <strong>in</strong>haled corticosteroids (>800 micg<br />
budesonide/day) or hospitalizations at their local hospital caused by airway symptoms<br />
where an anti-asthmatic drug was prescribed (pseudocroup episodes were excluded).<br />
Control group<br />
Children who developed neither bronchiolitis nor acute wheezy exacerbations before<br />
age 2 were considered as controls.<br />
<strong>Lung</strong> <strong>function</strong> <strong>measurements</strong><br />
Study II:<br />
Whole bodyplethysmography<br />
Children less than 7 years were tested us<strong>in</strong>g the whole body plethysmography to<br />
measure specific airway resistance (sRaw) as previously detailed (10, 11).<br />
Spirometry<br />
Children of 7 years and above used a spirometer to measure Forced Expiratory Volume<br />
<strong>in</strong> the first second (FEV 1 ) (Vitalograph Spirotrac) accord<strong>in</strong>g to the criteria of the<br />
American Thoracic Society (130).<br />
Bronchial responsiveness<br />
Children of 7 years and above were tested for responsiveness to methachol<strong>in</strong>e chloride<br />
with FEV 1 <strong>measurements</strong> before and 3 m<strong>in</strong>utes after each dose. Methachol<strong>in</strong>e was<br />
delivered <strong>in</strong> successively <strong>in</strong>creas<strong>in</strong>g doses accord<strong>in</strong>g to a protocol previously validated<br />
for school <strong>children</strong> (33) by an automatic, <strong>in</strong>halation synchronized, dosimetric jetnebulizer<br />
(Spira Elektro 2; Respiratory Care Center, Hämeenl<strong>in</strong>na, F<strong>in</strong>land). PD20<br />
value (mol) was calculated by l<strong>in</strong>ear <strong>in</strong>terpolation between the dose po<strong>in</strong>ts bracket<strong>in</strong>g<br />
the 20% fall <strong>in</strong> FEV 1 (131).<br />
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