Pulmonary artery pressure in term and preterm neonates

Area of Science:

• Neonatology
• Pediatric Cardiology
• Perinatal Physiology

Background:

• The transition of circulatory physiology after birth is critical for neonatal adaptation.
• Pulmonary artery pressure (PAP) regulation is a key aspect of this transition.
• Understanding factors influencing PAP post-birth is essential for identifying potential complications.

Purpose of the Study:

• To assess systolic pulmonary artery pressure (PAP) in term and preterm infants during the first 96 hours of life.
• To investigate the impact of prematurity and respiratory distress syndrome (RDS) on circulatory transition.
• To determine the relationship between ductal patency and postnatal circulatory adaptation.

Main Methods:

• Systolic PAP was measured using ductal Doppler flow velocity and systemic arterial pressure (SAP) in 41 term and 46 preterm infants.
• Infants were categorized into healthy term, preterm without RDS, and preterm with RDS.
• Sequential measurements were taken within the first 96 hours of life.

Main Results:

• Term infants showed a significantly higher PAP to SAP ratio at 2 and 12 hours compared to preterm infants without RDS.
• By 24 hours, the PAP to SAP ratio was similar across all groups.
• Preterm infants with RDS exhibited a significantly higher PAP to SAP ratio between 48 and 72 hours compared to those without RDS.

Conclusions:

• Healthy term infants achieve subsystemic pulmonary artery pressure within 12 hours, marking a critical circulatory transition.
• Prematurity alone did not significantly alter ductal closure times.
• Respiratory distress syndrome in preterm infants is associated with prolonged ductal patency and delayed circulatory adaptation, leading to pulmonary hypertension.