Inspiratory Effort and Dynamic Transpulmonary Driving Pressure in Extremely Preterm Infants.

Area of Science:

• Neonatology
• Pediatric Critical Care
• Respiratory Physiology

Background:

• Data on inspiratory effort (ΔP_es) and transpulmonary driving pressure (ΔP_L) are limited in preterm infants on noninvasive ventilation.
• Electrical activity of the diaphragm (EAdi) can estimate these pressures when patient size is a limitation.
• This estimation may offer insights into respiratory pathophysiology and self-inflicted lung injury risk.

Purpose of the Study:

• To characterize ΔP_es and ΔP_L in extremely preterm infants receiving noninvasive ventilation.

Main Methods:

• Prospective, observational pilot cohort study.
• Recorded EAdi in neonates with respiratory distress syndrome (RDS), evolving bronchopulmonary dysplasia (BPD), and term controls on noninvasive ventilation.
• Estimated ΔP_es and ΔP_L using EAdi; measured diaphragmatic thickening fraction (TF) and SpO₂/FiO₂ in a subset.

Main Results:

• Average EAdi, ΔP_es, ΔP_L, and TF were similar across groups.
• Inter-patient variability of ΔP_es and ΔP_L was significantly higher in preterm infants (RDS and BPD) than controls.
• High ΔP_es was more frequent in BPD; high ΔP_L was more frequent in RDS/BPD patients than controls and correlated inversely with SpO₂/FiO₂.

Conclusions:

• ΔP_es and ΔP_L exhibit significant variability in preterm infants on noninvasive support.
• High ΔP_es is more prevalent in BPD, while high ΔP_L is common in both RDS and BPD, indicating increased lung stress.
• These findings highlight the potential for lung injury and the importance of monitoring respiratory mechanics in these vulnerable infants.