Determination of the lung function by impulse oscillometry in 549 healthy children in Chengdu area / 中华儿科杂志

<p><b>OBJECTIVE</b>Impulse oscillometry (IOS) is a new method for determination of breathing mechanics, which features convenient operation, good repeatability and wider range analysis. As there is no standardized normal value in China at present, this study will provide a normal value of lung function determination by impulse oscillometry for children in Chengdu area.</p><p><b>METHOD</b>Totally 549 children were chosen at random from Chengdu area, with 292 boys and 257 girls who were 4 to 14 years old. The subjects were assigned into 10 age groups according to their chronological age with one year difference between every two adjacent groups. The respiratory total impedance (Zrs), viscosity resistance (Rrs) and elastic resistance (Xrs) at various oscillation frequency were measured by the Master Screen IOS which was manufactured by German Jaeger Company. The measured data were treated with the linear stepwise multiple regression, and established the prediction equation. At the same time, paired comparison was carried out with the measured data and equation obtained from this study, Lechtenboerger equation and prediction equation obtained from Guangzhou area.</p><p><b>RESULT</b>The total impedance and airway resistance were negatively correlated with the children's height and age. Zrs (male) = -0.756 + 189.586/height, r = -0.782, P < 0.001; Zrs (female) = -0.497 + 152.468/height, r = -0.726, P < 0.001. Rrs became the same in trend; while Xrs were proportional to the height, e.g. the values increased as the height increased. The difference of the airway resistance (R(5)-R(20)) was negatively correlated with the children's height: R(5)-R(20) (male) = 0.601 - 0.0034 x height, r = -0.677, P < 0.001; R(5)-R(20) (female) = 0.549 - 0.0031 x height, r = -0.658, P < 0.001. Among the relationships with many impulse oscillometry parameters, height ranked at first place; age at second. The multiple regression equation of IOS primary index was established. Both the measured data and the correlation coefficient of the study obtained equation were greater than the coefficient correlation of the Lechtenboerger equation, but had no significant difference compared with that of prediction equation in Guangzhou area.</p><p><b>CONCLUSION</b>The normal value in impulse oscillometry in children in Chengdu area is different from the predicted parameters in other countries. The equation obtained from this study seems to be more suitable for the children in its local area. It is recommended to apply the predicted value from the corresponding population in the determination of the lung function by impulse oscillometry.</p>

Survey on prevalence of 1 526 children with sleep disturbances in age of 2 to 12 years old in Chengdu / 中华预防医学杂志

<p><b>OBJECTIVE</b>To find out the prevalence of sleep disturbances for children aged 2 to 12 years old in Chengdu.</p><p><b>METHODS</b>Totally 1 600 children aged 2-12 years old were selected from 5 districts in Chengdu and investigated by using questionnaire.</p><p><b>RESULTS</b>All 1 526 survey papers were returned. The average time of every day sleep in each age group (infant group, pre-school age group and school age group) were 12.12 hours, 10.42 hours and 9.47 hours. The sleep time of the children in those three groups were much less than the standard one. The proportion of the prevalence of sleep disturbance was 37.88%. Among them, there were snoring in 5.57%, choke/gargling in 1.25%, sleep inquietude in 7.86%, mouth breathing in 4.59%, sweating in 21.36%, member spasm in 2.82%, molar teeth in 8.26%, night talking in 4.02%, somnambulate in 0.2%, bedwetting in 1.95%, and difficulty falling asleep in 10.75%. There were significant differences shown in different sexes and ages, and in incidence of symptoms of some sleep disturbances. The affecting factors were the co-sleeping, tonsillitis, bronchitis, pollen allergy and their parent's snore.</p><p><b>CONCLUSION</b>The prevalence of sleep disturbances being higher and more severe than before might be due to the less sleeping time in Chengdu in children aged 2 to 12 years old. More attention should be paid by parents, the Ministry of Education and the children's doctors.</p>