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Forced expiratory flows and volumes in infants. Normative data and lung growth

M Jones1, R Castile, S Davis

  • 1Department of Pediatrics, James Whitcomb Riley Hospital for Children, Indiana University Medical Center, Indianapolis, Indiana 46223, USA.

American Journal of Respiratory and Critical Care Medicine
|February 15, 2000
PubMed

Insights

This study establishes reference values for infant lung function, finding that lung volume grows rapidly in the first year. Maternal smoking and being male are associated with reduced forced expiratory flows (FEF) in infants.

Area of Science:

  • Pediatric Pulmonology
  • Respiratory Physiology
  • Infant Lung Development

Background:

  • Establishing normative data for infant lung function is crucial for assessing respiratory health and growth.
  • Forced expiratory flows (FEF) provide insights into airway caliber and lung emptying dynamics.

Purpose of the Study:

  • To establish reference values for forced expiratory flows (FEF) in healthy infants.
  • To evaluate the influence of age, body length, and maternal smoking on infant lung function.
  • To assess lung growth patterns and airway-to-lung volume relationships in early life.

Main Methods:

  • Measurements of forced expiratory flows (FEF) and forced vital capacity (FVC) were obtained in 155 healthy infants aged 3 to 149 weeks.
  • Statistical analyses were performed to correlate lung function parameters with body length and age.
  • Infants were categorized based on maternal smoking status and sex for comparative analysis.

Main Results:

  • Forced vital capacity (FVC) correlated significantly with body length and age.
  • Infants exposed to maternal smoking exhibited lower forced expiratory flows (FEF).
  • Male infants showed lower FEF(75) compared to female infants.
  • The ratio of FEV(0.5)/FVC decreased with increasing body length, indicating faster relative lung emptying in smaller infants.

Conclusions:

  • The study provides valuable reference values for infant forced expiratory flows (FEF).
  • Maternal smoking and male sex are associated with reduced infant lung function.
  • Infant lung volume increases rapidly during the first year, with proportionally large airways early in life.

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