Effects of Lung-Protective Ventilation on Cerebral Oxygenation During One-Lung Ventilation in Neonates

Objective: This study aimed to investigate the effects of different lung ventilation strategies on cerebral oxygen saturation (rSO 2 ) during one-lung ventilation (OLV) in neonates. Methods: A total of 50 neonates scheduled for elective OLV between October 2022 and April 2024 were enrolled and randomly assigned to either the control group (Group C) or the study group (Group S). In Group S, the respiratory rate was adjusted to maintain end-tidal carbon dioxide (PETCO 2 ) levels between 45– 55 mmHg at 30 minutes of OLV (T3) and subsequently restored to normal levels (35– 45 mmHg) at 45 minutes of OLV (T4). Lung recruitment maneuvers were applied. In Group C, PETCO 2 was maintained within the normal range throughout the procedure. Oxygen saturation (SpO 2 ) and rSO 2 , along with additional physiological parameters, were recorded at five time points: before OLV (T1), 15 minutes after OLV initiation (T2), T3, T4, and 60 minutes after OLV initiation (T5). Arterial blood samples were collected for blood gas analysis. Results: In both groups, rSO 2 levels significantly decreased during OLV compared to baseline (T1) ( p < 0.05). However, at T3, rSO 2 was significantly higher in Group S compared to Group C. Comparisons within the group indicated that rSO 2 in Group S at T3 was significantly higher than at T5. Lung compliance was superior in Group S compared to Group C at T5. Furthermore, lung compliance in both groups decreased at T2 when compared to T1 ( p < 0.05). Conclusion: Despite maintaining SpO 2 within the normal range, rSO 2 declined during OLV in neonates. The application of permissive hypercapnia during OLV improved rSO 2 within a certain range. Routine perioperative monitoring of rSO 2 in neonates undergoing OLV may facilitate early detection of cerebral oxygenation changes, contributing to neuroprotection. Keywords: cerebral oxygen saturation, hypercapnia, lung protected ventilation, lung recruitment, neonates, one lung ventilation