Haemodynamic changes and mean airway pressure threshold in extremely preterm infants (22-24 weeks of gestation) with...

Extremely preterm infants (22-24 weeks of gestation) are at high risk of tension pneumothorax, a life-threatening condition that causes haemodynamic instability. This study aimed to analyse the haemodynamic changes associated with tension pneumothorax and identify the mean airway pressure (MAP) threshold associated with its onset.

This retrospective descriptive study was conducted in a Level III Neonatal Intensive Care Unit (NICU) (2014-2024). Infants born between 22 + 0 to 24 + 6 weeks of gestation who developed tension pneumothorax within 72 h of birth were included. Haemodynamic parameters, including central venous pressure (CVP), mean arterial pressure (mBP), heart rate (HR), saturation of percutaneous oxygen (SpO₂), fraction of inspired oxygen (FiO₂), and MAP, were analysed at baseline, pneumothorax onset, and post-decompression. Statistical analyses included the Wilcoxon signed-rank test and generalised linear mixed model (GLMM).

The CVP significantly increased at the onset of pneumothorax (p = 0.004) and decreased post-intervention (p = 0.004). The mBP and HR declined at onset (p = 0.0005) and partially recovered post-intervention. MAP was significantly higher at onset (p = 0.003), and GLMM analysis showed that an MAP increase of ≥1.3 cmH₂O was associated with pneumothorax risk.

A sudden increase in CVP may serve as an early indicator of tension pneumothorax. An MAP threshold of ≥12 cmH₂O was linked to higher pneumothorax risk, emphasising the need for cautious ventilatory management. Persistent haemodynamic instability after decompression highlights the need for close monitoring. Further studies are required to refine the neonatal care strategies.