Effect of Pharmacological Closure Therapy on Vital Organ Oxygenation in Premature Infants with Hemodynamically Significant Patent Ductus Arteriosis: Assessment by Near-Infrared Spectroscopy

Background: Hemodynamically significant patent ductus arteriosus (hsPDA) is a frequent problem in preterm infants and may impair systemic and organ-specific oxygenation. Near-infrared spectroscopy (NIRS) provides a noninvasive tool to evaluate regional tissue oxygenation. Our aim was to investigate the effects of pharmacological closure therapy on cerebral, renal, and mesenteric tissue oxygenation in preterm infants diagnosed with hsPDA. Methods: This prospective observational study was conducted in a tertiary neonatal intensive care unit between September 2021 and November 2024. Twenty-four preterm infants (24–34 weeks gestational age) with hsPDA confirmed by echocardiography were enrolled. Patients received either ibuprofen or paracetamol based on contraindications. Regional tissue oxygen saturation (rSpO₂) and fractional tissue oxygen extraction (FTOE) were monitored continuously using NIRS for 72 hours before and after treatment. Echocardiographic and hemodynamic parameters were also recorded. Results: Ductus closure was achieved in 46% of cases and significant narrowing in 29%. Ibuprofen treatment resulted in a significant reduction in ductal diameter (p=0.002), whereas paracetamol did not (p=0.074). Diastolic and mean blood pressure increased significantly after treatment. Mesenteric rSpO₂ improved significantly at 24–48 hours in the ibuprofen group (p=0.01), while cerebral and renal oxygenation remained unchanged. Conclusion: Pharmacological therapy, particularly ibuprofen, improved hemodynamic stability and mesenteric oxygenation in preterm infants with hsPDA. Mesenteric rSpO₂ may serve as a more sensitive marker of treatment response than cerebral or renal oxygenation. Larger multicenter studies are warranted to confirm these findings.