title: Prevalence of tidal expiratory flow limitation in preschool children with and without respiratory symptoms: application of the negative expiratory pressure (NEP) method.
abstract: Negative expiratory pressure (NEP) applied at the mouth during tidal expiration provides a non-invasive method for detecting expiratory flow limitation. Forty-two children were studied, i.e. 25 children with different respiratory symptoms (R) and 17 without any respiratory symptoms (NR). Children were examined without any sedation. A preset NEP of -5 cm H(2)O was applied; its duration did not exceed duration of tidal expiration. A significance of FL was judged by determining of a flow-limited range (in % of tidal volume). FL was found in 48 % children of R group. No patient of the NR group elicited FL (P<0.001 R vs. NR). The frequency of upper airway collapses was higher in R group (12 children) than in NR group (5 children). In conclusion, a high frequency of tidal FL in the R group was found, while it was not present in NR group. A relatively high frequency of expiratory upper airway collapses was found in both groups, but it did not differ significantly. NEP method represents a reasonable approach for tidal flow limitation testing in non-sedated preschool children.
authors.affiliation: Institute of Physiology, First Faculty of Medicine, Department of Physiology, Charles University, Prague, Czech Republic. adriana.jirickova@lf1.cuni.cz
authors.forename: A
authors.initials: A
authors.lastname: Jirickova
authors.forename: J
authors.initials: J
authors.lastname: Sulc
authors.forename: P
authors.initials: P
authors.lastname: Pohunek
authors.forename: O
authors.initials: O
authors.lastname: Kittnar
authors.forename: A
authors.initials: A
authors.lastname: Dohnalova
authors.forename: J
authors.initials: J
authors.lastname: Kofranek
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D005540:Forced Expiratory Flow Rates; D006801:Humans; D007223:Infant; D008168:Lung / Q000503:physiopathology*; D008171:Lung Diseases / Q000503:physiopathology*; D008297:Male; D011312:Pressure; D012121:Respiration, Artificial / Q000379:methods*; D012129:Respiratory Function Tests / Q000379:methods*; D015656:Respiratory Mechanics; D013990:Tidal Volume