WIP 65 - Characterizing Nasal CPAP to High Flow Nasal Cannula Transitions in Preterm Infants using Electrical Impedance Tomography: A Prospective, Observational Study

Poster Number: WIP 65
Publication Number: WIP 65.738

Background: In the neonatal intensive care unit, non-invasive respiratory support is used as primary therapy to prevent intubation or as transitional therapy following extubation. High flow nasal cannula (HFNC) therapy and nasal CPAP (NCPAP) are the two most used modalities. Although the practice of transitioning from NCPAP to HFNC is common, a standard method of transitioning between devices does not currently exist. This is due, in part, to limited physiologic data describing how the devices differ in supporting neonatal breathing. We hypothesize that transition from NCPAP to HFNC leads to a loss of end-expiratory lung volume.

Objective: To evaluate and compare changes in end expiratory lung volume associated with transition from NCPAP to HFNC using electrical impedance tomography (EIT).

Design/Methods: This prospective, observational study began enrollment at The Children’s Hospital of Philadelphia Neonatal/Infant Intensive Care Unit in July 2023. Infants < 32 weeks gestational age and between 30 and 50 weeks corrected age currently receiving CPAP therapy with the plan to transition to HFNC are included in the study. To date, 8 subjects (target enrollment 17 patients) have been enrolled and recorded.
An hour prior to transition between NCPAP and HFNC, an EIT belt is placed at the patient’s nipple line and connected to a Lumon EIT monitor (SenTec AG, Landquart, Switzerland). Breathing is then recorded before, during, and after transition from NCPAP to HFNC, approximately 2 hours total. Transition timing and respiratory support levels are dictated by the clinical team. EIT data are extracted using a Sentec EIT Viewer (Sentec AG, Landquart, Switzerland). Vital signs and respiratory data are recorded every 5 minutes during the recordings and then extracted from the medical record every 24 hours for 7 days post-recording.
Differences in mean and median end-expiratory lung impedance before and after transition from NCPAP to HFNC will be analyzed using paired t-tests and Wilcoxon ranked-sign tests, respectively, using STATA (Version 16.1, Statacorp, Texas, USA).