In vivo mechanical properties of the developing airway.

Publication/Presentation Date

2-1-1989

Abstract

The inherent mechanical characteristics of the airways are determined in part by their elastic and viscoelastic properties. As compliant structures during early development, the airways are susceptible to significant distention and collapse, depending on the proportionality between airway volume and transmural pressure. To characterize the age-related changes in airway mechanical properties, the elastic and viscoelastic behavior of in vivo tracheal segments were evaluated in preterm and newborn lambs over a wide range of developmental age (108 to 154 days postconceptional age). Tracheal pressure-vol relationships and concomitant airway compliance measurements were used to determine elastic behavior. Calculations of the tracheal relaxation time constant on the same tracheal segments were used to evaluate airway viscoelastic behavior. Data demonstrated a significant (p less than 0.01) correlation with developmental age. With increasing age, the airways were found to be less compliant, and the tracheal relaxation time constant was observed to decrease. The difference in elastic properties of the trachea, in vivo compared to in vitro, suggest that neural-humoral and surrounding connective tissue factors may affect the elasticity of the developing airway. Although the modulating effects of smooth muscle tone and supporting connective tissue assist in the control of airway dimension and resistance to airflow in the intact airway, the age-related differences in the elastic properties may be a factor that predisposes the more immature airway to positive pressure-induced damage.

Volume

25

Issue

2

First Page

143

Last Page

146

ISSN

0031-3998

Disciplines

Business Administration, Management, and Operations | Health and Medical Administration | Management Sciences and Quantitative Methods

PubMedID

2919128

Department(s)

Administration and Leadership

Document Type

Article

Link to Full Text

Share

COinS