Background: Surgical closure of a patent ductus arteriosus (PDA) in very low birth weight (VLBW) infants has been associated with impaired neurodevelopmental outcome. Surgical PDA closure may result in abrupt changes of cerebral haemodynamics.
Objective: To examine the cerebral blood volume changes occurring after surgical closure of PDA.
Design: Continuous cerebral near-infrared spectroscopy (NIRS) recording throughout PDA surgery.
Setting: Tertiary neonatal intensive care unit, with PDA surgery performed on the ward.
Patients: Ten VLBW infants, median birth weight 748 g (range 590-1070), gestational age 24 (23-27) weeks, chronological age 14 (12-22) days.
Intervention: Surgical closure of PDA.
Main outcome measures: Changes in cerebral oxygenated haemoglobin, cerebral deoxygenated haemoglobin, and tissue oxygenation index (measured), changes in cerebral blood volume (CBV) and cerebral haemoglobin difference (calculated) as measured by NIRS.
Results: During the first 2 minutes after closure of the PDA, CBV increased significantly (mean (SD) 0.14 (0.12) ml/100 g tissue; p = 0.01) and returned to baseline within 2-5 minutes. Cerebral oxygenation did not change.
Conclusions: There is a short-lasting increase in CBV immediately after surgical closure of PDA, but no change in cerebral oxygenation. These transient changes are unlikely to cause harm.