A new ovine model of spine and chest wall deformity at birth with alteration of respiratory system mechanics and lung development: a feasibility study

Abstract

Purpose: To develop an animal model of spine and chest wall deformity (CWD) at birth and to evaluate its effects on respiratory system mechanics and lung development.

Methods: A spine and CWD was created in utero between 70 and 75 days of gestation in six ovine fetuses by resection of the seventh and eighth left ribs. Two days after birth, respiratory system mechanics was assessed in anesthetized lambs using the flexiVent apparatus, followed by postmortem measurement of lung mechanics as well as histological lung analysis.

Results: A range of severity of CWD was found (Cobb angle from 0° to 48°) with a mean decrease in compliance of 47% and in inspiratory capacity of 39% compared to control lambs. Proof-of-concept histological analysis in one lamb showed marked lung hypoplasia.

Conclusion: Our ovine model represents a pilot proof-of-concept study evaluating the impact of a spine and CWD present at birth on lung respiratory mechanics and development. This study lays down the groundwork for future studies evaluating the impact of these deformities on lung development and potential treatments. These slides can be retrieved under Electronic Supplementary Material.

Keywords: Animal model; Chest wall deformity; Fetal surgery; Lamb; Respiratory function.