Abstract
BACKGROUND: Little is known about the effects of carbon dioxide (CO2) insufflation on cerebral oxygenation during thoracoscopy in neonates. Near-infrared spectroscopy can measure perioperative brain oxygenation [regional cerebral oxygen saturation (rScO2)]. AIMS: To evaluate the effects of CO2 insufflation on rScO2 during thoracoscopic esophageal atresia (EA) repair. METHODS: This is an observational study during thoracoscopic EA repair with 5 mmHg CO2 insufflation pressure. Mean arterial blood pressure (MABP), arterial oxygen saturation (SaO2), partial pressure of arterial carbon dioxide (paCO2), pH, and rScO2 were monitored in 15 neonates at seven time points: baseline (T0), after anesthesia induction (T1), after CO2-insufflation (T2), before CO2-exsufflation (T3), and postoperatively at 6 (T4), 12 (T5), and 24 h (T6). RESULTS: MABP remained stable. SaO2 decreased from T0 to T2 [97 ± 3-90 ± 6 % (p < 0.01)]. PaCO2 increased from T0 to T2 [41 ± 6-54 ± 15 mmHg (p < 0.01)]. pH decreased from T0 to T2 [7.33 ± 0.04-7.25 ± 0.11 (p < 0.05)]. All parameters recovered during the surgical course. Mean rScO2 was significantly higher at T1 compared to T2 [77 ± 10-73 ± 7 % (p < 0.05)]. Mean rScO2 levels never dropped below a safety threshold of 55 %. CONCLUSION: The impact of neonatal thoracoscopic repair of EA with insufflation of CO2 at 5 mmHg was studied. Intrathoracic CO2 insufflation caused a reversible decrease in SaO2 and pH and an increase in paCO2. The rScO2 was higher at anesthesia induction but remained stable and within normal limits during and after the CO2 pneumothorax, which suggest no hampering of cerebral oxygenation by the thoracoscopic intervention. Future studies will focus on the long-term effects of this surgery on the developing brain.