Diaphragmatic Ultrasonography in Preterm Newborns With Respiratory Distress Syndrome on Invasive Mechanical Ventilation: An Observational Study.

Aim: In preterm newborns, Respiratory Distress Syndrome (RDS) is one of the leading causes of mortality. Treatment often requires invasive mechanical ventilation (IMV), which can cause diaphragmatic dysfunction. Ultrasonography is a promising tool for assessing diaphragmatic function in neonates. This study analyses changes in the diaphragm muscle of preterm newborns with RDS undergoing IMV.

Methods: A longitudinal study was conducted with preterm newborns diagnosed with RDS and subjected to IMV. Clinical data were collected, and ultrasonographic evaluations of diaphragm thickness and diaphragmatic thickening fraction (DTF) were performed at two time points: within the first 48 h of life and up to 48 h after extubation.

Results: There was a significant reduction in diaphragmatic thickness (p < 0.0001), DTF index (p = 0.01), and diaphragmatic excursion (p = 0.02) during the intubation period. A moderate correlation was observed between DTF and IMV duration (R = 0.62), hospitalisation time (R = 0.52), and the risk of reintubation (R = 0.55). A moderate correlation was also identified between IMV duration and hospitalisation time (R = 0.64) and between diaphragmatic thickness and gestational age (R = 0.58). However, the correlation between DTF and gestational age was weak (R = 0.48).

Conclusion: IMV leads to diaphragmatic deterioration with increased muscle atrophy in preterm newborns with respiratory distress syndrome.