TY - JOUR
T1 - Changes in ventilation homogeneity from preschool through young adulthood as determined by moment analysis of nitrogen washout
AU - Wall, Michael A.
AU - Misley, Mary C.
AU - Brown, Arthur
N1 - Copyright:
Copyright 2020 Elsevier B.V., All rights reserved.
PY - 1988/1
Y1 - 1988/1
N2 - This study was designed to assess potential differences in ventilation homogeneity related to growth. One hundred thirty-three healthy subjects representing four stages of growth were studied: group 1, preschool, ages 34-74 months; group 2, préadolescent, ages 8-10 yr; group 3, postpubertal, ages 15-17 yr; group 4, young adult, ages 26-40 yr. Ventilation homogeneity was assessed by moment analysis of multibreath nitrogen washout with functional residual capacity, the ratio of the 1st to 0th moment (MR 1/0), and the ratio of the 2nd to 0th moment (MR 2/0) being the outcome variables of interest. Across the four groups functional residual capacity increased as a curvilinear function of height. At all heights functional residual capacity was larger in males than females and the slope of the regression was steeper in males than females (p < 0.001). Both MRs 1/0 and 2/0 were significantly higher in group 1 than the other groups, indicating that ventilation washout was less homogeneous in the preschool subjects than in older children or adults. Males of group 1 had significantly higher values for both moment ratios (more ventilation nonuniformity) than females. In the other groups there were no significant sex based differences although there was a trend for males to have a lower MR 1/0 than females in the young adults, p = 0.08. The results indicate that both age and sex are important determinants of the growth of distribution of ventilation.
AB - This study was designed to assess potential differences in ventilation homogeneity related to growth. One hundred thirty-three healthy subjects representing four stages of growth were studied: group 1, preschool, ages 34-74 months; group 2, préadolescent, ages 8-10 yr; group 3, postpubertal, ages 15-17 yr; group 4, young adult, ages 26-40 yr. Ventilation homogeneity was assessed by moment analysis of multibreath nitrogen washout with functional residual capacity, the ratio of the 1st to 0th moment (MR 1/0), and the ratio of the 2nd to 0th moment (MR 2/0) being the outcome variables of interest. Across the four groups functional residual capacity increased as a curvilinear function of height. At all heights functional residual capacity was larger in males than females and the slope of the regression was steeper in males than females (p < 0.001). Both MRs 1/0 and 2/0 were significantly higher in group 1 than the other groups, indicating that ventilation washout was less homogeneous in the preschool subjects than in older children or adults. Males of group 1 had significantly higher values for both moment ratios (more ventilation nonuniformity) than females. In the other groups there were no significant sex based differences although there was a trend for males to have a lower MR 1/0 than females in the young adults, p = 0.08. The results indicate that both age and sex are important determinants of the growth of distribution of ventilation.
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U2 - 10.1203/00006450-198801000-00015
DO - 10.1203/00006450-198801000-00015
M3 - Article
C2 - 3340449
AN - SCOPUS:0023833855
SN - 0031-3998
VL - 23
SP - 67
EP - 71
JO - Pediatric Research
JF - Pediatric Research
IS - 1
ER -