# Evaluating Clinically Directed Continuous Positive Airway Pressure to High Flow Nasal Cannula Transitions in Stable Preterm Infants Using Electrical Impedance Tomography: A Prospective, Observational Study

## TL;DR

This study used EIT to evaluate lung aeration changes in preterm infants during a transition from CPAP to HFNC, finding no consistent decrease in lung aeration.

## Contribution

The study introduces EIT as a tool to observe real-time lung aeration changes during CPAP to HFNC transitions in preterm infants.

## Key findings

- No significant difference in end-expiratory lung impedance was found between HFNC and CPAP.
- A distinct respiratory pattern was observed in the infant who failed the transition, marked by a decrease in EELI and frequent recruitment breaths.

## Abstract

To assess lung aeration changes during clinically directed transitions from CPAP to HFNC in preterm infants using Electrical Impedance Tomography (EIT).

Prospective, observational study.

Single‐center, Level IV Neonatal Intensive Care Unit.

Infants born < 32 weeks gestational age (GA) undergoing a clinically indicated transition from CPAP to HFNC following ≥ 2 weeks of respiratory support.

EIT data were recorded for 30–60 min before and after transition.

The primary outcome was change in end‐expiratory lung impedance (ΔEELI). Infants were followed for 7 days following transition to assess for transition failure.

From 15 subjects, 4257 total breaths were analyzed. No significant difference in %∆EELI was found between HFNC and CPAP (Median ∆: –1.0%; IQR –3.6% to 6.0%; p = 0.78). The largest %∆EELI decrease (–9.8%) occurred in the subject who failed transition.

Transitioning from CPAP to HFNC did not consistently decrease lung aeration in stable preterm infants. In the infant who failed transition, a distinct respiratory pattern was observed using EIT, characterized by a decrease in EELI and frequent recruitment breaths. These findings suggest better methods are needed to individualize and titrate respiratory support at the bedside for preterm infants.