Agreement of Diaphragmatic Excursion Between Anterior Subcostal and Posterior Subcostal Ultrasonography in Premature...

Diaphragmatic ultrasound (DUS) is a non-invasive technique used to assess diaphragmatic function in neonates. However, the assessment of the diaphragm in the prone position is limited, as DUS traditionally uses the supine position. The agreement between the anterior subcostal approach (ASC), in the supine position, and the posterior subcostal approach (PSC), in the prone position, has not yet been studied.

To determine the agreement of diaphragmatic excursion between the ASC in the supine position and PSC in the prone position at the bedside using DUS in preterm neonates.

A cross-sectional study was conducted with clinically stable preterm neonates admitted to the neonatal ward. All participants underwent diaphragmatic excursion assessment by ultrasound, using the ASC in the supine position and the PSC in the prone position. The agreement analysis between the approaches was performed using the Bland-Altman method, following a logarithmic transformation of the data. Agreement was evaluated based on the mean bias, standard deviation (SD), limits of agreement (LOA), and 95% confidence intervals (CI).

Thirty-five preterm neonates with a gestational age of 33.42 ± 1.31 weeks were included. A good agreement was identified between the measurements, with a mean bias of 0.97 mm and limits of agreement between 0.71 mm and 1.32 mm.

The PSC approach in the prone position may be an alternative to the ASC in the supine position for assessing diaphragmatic excursion by DUS. This study expands the possibilities for functional assessment of the diaphragm in different neonatal clinical settings.