Extubation generates lung volume inhomogeneity in preterm infants

Area of Science:

• Neonatal respiratory physiology
• Medical imaging techniques
• Critical care medicine

Background:

• Extubation from invasive ventilation to non-invasive support is critical for preterm infants.
• Understanding regional lung function during this transition is essential for optimizing outcomes.
• Electrical impedance tomography (EIT) offers a non-invasive method to assess lung aeration and ventilation.

Purpose of the Study:

• To assess the feasibility of using EIT to monitor regional tidal ventilation (V_T) and end-expiratory lung volume (EELV) changes in preterm infants during extubation.
• To describe lung volume loss and ventilation patterns during the transition from invasive ventilation to nasal continuous positive airway pressure (nCPAP).

Main Methods:

• A prospective observational study was conducted in a single-center tertiary neonatal intensive care unit.
• EIT measurements were performed on preterm infants (<32 weeks' gestation) undergoing elective extubation.
• Data on global and regional ΔEELV, ΔV_T, heart rate, respiratory rate, and oxygen saturation were collected before, during, and after extubation to nCPAP.

Main Results:

• EIT successfully described complex lung conditions during extubation to nCPAP.
• End-expiratory lung volume (EELV) decreased post-extubation, with primary loss in the ventral lung regions (p=0.04).
• Tidal ventilation (V_T) initially increased, particularly in central and ventral areas, before returning to baseline with nCPAP application.

Conclusions:

• EIT is feasible for monitoring regional lung volume and ventilation patterns in preterm infants during extubation.
• The study identified significant lung volume loss and altered ventilation distribution during the transition to nCPAP.
• EIT may play a role in guiding respiratory support strategies during the peri-extubation period.