Am. J. Respir. Crit. Care Med., Vol 154, No. 3, 09 1996, 689-694.
Pulmonary function during the first year of life following acute viral bronchiolitis
IT Merth, JP de Winter, HM Zonderland, R Brand and PH Quanjer
Department of Paediatrics, Leiden University, the Netherlands.
It has been suggested that acute viral bronchiolitis in infants may result
in functional changes that predispose toward chronic pulmonary disease
later in life. We assessed pulmonary function (PF) during the acute phase
of viral bronchiolitis in infants and up to 12 mo later from static
respiratory system compliance (Crs), using weighted spirometry, the
distribution of ventilation by the mixing index (MI), and the functional
residual capacity (FRC) measured by closed-circuit helium dilution (FRCHe).
The study was performed in 24 infants (13 males and 11 females; median [25
to 75% range] age: 11 [9.6 to 13.3] wk; weight: 4.8 [4.3 to 5.0] kg;
crown-to-heel length: 57.7 [55.5 to 59.0] cm) at admission and at 2 wk. In
17 infants, measurements were repeated 3 mo and 12 mo later. Predicted
values and individual 95% prediction intervals for Crs, MI, and FRCHe were
derived from 69 healthy infants (33 boys and 36 girls; median age [25 to
75% range]: 4.7 [2.0 to 21.4] wk; weight: 3.6 [3.0 to 6.9] kg;
crown-to-heel length: 51.5 [48 to 61] cm). Data at admission and after
discharge were compared by analysis of variance (ANOVA) with those in the
healthy controls matched for crown-to-heel length. At admission all three
variables gave lower average results than predicted means. Values for each
index had attained a normal level 2 wk after admission; normal levels were
maintained at 3 and 12 mo. The prevalence of recurrent wheezing (five of
the 17 infants) was comparable with that reported in population studies.
These findings suggest that in this population acute viral bronchiolitis
did not lead to permanent changes in PF.
