Lung function in preschool children with a history of wheezing measured by forced oscillation and plethysmographic specific airway resistance.
BACKGROUND
Wheezing is common in preschool children, but objective evidence for airway obstruction and its reversibility are rarely available in clinical practice. We assessed whether abnormalities of lung function and bronchodilator response can be detected in preschool children using the forced oscillation technique and measurements of specific airway resistance.


METHODS
Fifty-nine children with a history of wheeze and 24 healthy controls aged 3-6 years were recruited. Resistance and reactance at 6 and 8 Hz (Rrs6, Rrs8, Xrs6 and Xrs8, respectively) were measured using the forced oscillation technique and specific airway resistance was measured in a plethysmograph. z-Scores were calculated from published reference data. Tests were repeated 15 min after 400 mcg salbutamol. Bronchodilator response was expressed as the log-transformed ratio of postbronchodilator/prebronchodilator values.


RESULTS
Technically acceptable measurements using the forced oscillation technique were obtained in n = 77 (93%) of children and in n = 56 (68%) using plethysmography. There was no significant difference in baseline lung function or bronchodilator response, assessed by either technique, between those with a history of wheeze and healthy controls.


CONCLUSIONS
Measurement of lung function is feasible in preschool children, but neither of these techniques was able to identify diminished lung function or reversibility to bronchodilator in children with a history of wheeze.
Harrison
Jo
J
Infection, Immunity & Environment Theme, Murdoch Children's Research Institute, Melbourne, VIC, Australia. jo.harrison@mcri.edu.au
Gibson
Anne-Marie
AM
Johnson
Khrista
K
Singh
Gauharjit
G
Skoric
Billy
B
Ranganathan
Sarath
S
D000403:Airway Resistance / Q000187:drug effects / Q000502:physiology*; D000420:Albuterol / Q000494:pharmacology; D001249:Asthma / Q000503:physiopathology; D001993:Bronchodilator Agents / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008168:Lung / Q000187:drug effects / Q000503:physiopathology*; D008297:Male; D010991:Plethysmography; D012129:Respiratory Function Tests / Q000379:methods; D012135:Respiratory Sounds / Q000187:drug effects / Q000503:physiopathology*
D001993:Bronchodilator Agents; D000420:Albuterol