TY - JOUR
T1 - Changes in the contribution of the rib cage to tidal breathing during infancy
AU - Hershenson, M. B.
AU - Colin, A. A.
AU - Wohl, M. E.B.
AU - Stark, A. R.
PY - 1990
Y1 - 1990
N2 - As the shape, compliance, and deformability of the rib cage (RC) change during infancy, RC participation in quiet breathing may increase. We used respiratory inductive plethysmography (RIP) to determine the relative contributions of the RC and abdomen (AB) to tidal volume (VT) in 20 studies in 14 healthy infants 1 to 26 months of age during quiet natural sleep. RIP was calibrated with simultaneous flow measurement (anesthesia mask and pneumotachograph) by the least squares method of statistical analysis. We analyzed segments of breathing with and without flow measurement for RIP-derived VT, change in RC volume (Vrc) and AB volume (Vab) with each breath and the RC contribution to tidal breathing (%RC = Vrc/Vrc + Vab). The %RC increased with age: %RC = 1.4 age (months) + 33 (r = 0.69, p < 0.01). After 9 months of age, %RC resembled that found in quietly sleeping adolescents. Mask placement increased VT in all but one subject (mean increase, 29 ± 23% of baseline ± SD; p < 0.001, paired t test). In infants younger than 10 months of age, mask placement also increased %RC (without mask, 40 ± 9%; with mask, 46 ± 10%; p < 0.02). We conclude that by 1 yr of age, the RC contribution to tidal breathing during quiet sleep is similar to that of the adolescent, suggesting that major developmental changes in RC shape, compliance, and deformability take place during infancy.
AB - As the shape, compliance, and deformability of the rib cage (RC) change during infancy, RC participation in quiet breathing may increase. We used respiratory inductive plethysmography (RIP) to determine the relative contributions of the RC and abdomen (AB) to tidal volume (VT) in 20 studies in 14 healthy infants 1 to 26 months of age during quiet natural sleep. RIP was calibrated with simultaneous flow measurement (anesthesia mask and pneumotachograph) by the least squares method of statistical analysis. We analyzed segments of breathing with and without flow measurement for RIP-derived VT, change in RC volume (Vrc) and AB volume (Vab) with each breath and the RC contribution to tidal breathing (%RC = Vrc/Vrc + Vab). The %RC increased with age: %RC = 1.4 age (months) + 33 (r = 0.69, p < 0.01). After 9 months of age, %RC resembled that found in quietly sleeping adolescents. Mask placement increased VT in all but one subject (mean increase, 29 ± 23% of baseline ± SD; p < 0.001, paired t test). In infants younger than 10 months of age, mask placement also increased %RC (without mask, 40 ± 9%; with mask, 46 ± 10%; p < 0.02). We conclude that by 1 yr of age, the RC contribution to tidal breathing during quiet sleep is similar to that of the adolescent, suggesting that major developmental changes in RC shape, compliance, and deformability take place during infancy.
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U2 - 10.1164/ajrccm/141.4_pt_1.922
DO - 10.1164/ajrccm/141.4_pt_1.922
M3 - Article
C2 - 2139308
AN - SCOPUS:0025213359
VL - 141
SP - 922
EP - 925
JO - American Journal of Respiratory and Critical Care Medicine
JF - American Journal of Respiratory and Critical Care Medicine
SN - 1073-449X
IS - 4 I
ER -