Birth Weight and Diaphragmatic Ultrasound Measurements During the First 48 Hours in Term Neonates: A Secondary Longitudinal Analysis

Background/Objectives: Neonatal diaphragm ultrasound measurements may vary with body size. We examined associations between birth weight and repeated bilateral diaphragm measurements during the first 48 h after birth.

Methods

This exploratory secondary post hoc analysis included 116 term neonates assessed at approximately 1, 24, and 48 h (348 examinations). Associations of birth weight with diaphragm thickness, diaphragmatic thickening fraction (DTF), and excursion were estimated using generalized estimating equations adjusted for gestational age, sex, and assessment time. Mean bilateral end-expiratory thickness was a derived post hoc summary, and absolute inspiratory thickening (ΔT) was examined additionally.