Decreased cerebral oxygen saturation during thoracoscopic repair of congenital diaphragmatic hernia and esophageal atresia in infants.

Abstract: Background/Purpose: Congenital diaphragmatic hernia (CDH) and esophageal atresia with tracheoesophageal fistula (EA/TOF) can be repaired thoracoscopically, but this may cause hypercapnia, acidosis, and reduced cerebral oxygenation. We evaluated the effect of thoracoscopy in infants on cerebral oxygen saturation (cSO₂), arterial blood gases, and carbon dioxide (CO₂) absorption. Methods: Eight infants underwent thoracoscopy (6 CDH and 2 EA/TOF). Serial arterial blood gases were taken. Regional cSO₂ was measured using near-infrared spectroscopy. Absorption of insufflated CO₂ was calculated from exhaled ¹³CO₂/¹²CO₂ ratio measured by mass spectrometry. Results: CO₂ absorption increased during thoracoscopy with a maximum 29% ± 6% of exhaled CO₂ originating from the pneumothorax. Paco ₂ increased from 9.4 ± 1.3 kPa at the start to 12.4 ± 1.0 intraoperatively and then decreased to 7.6 ± 1.2 kPa at end of operation. Arterial pH decreased from 7.19 ± 0.04 at the start to 7.05 ± 0.04 intraoperatively and then recovered to 7.28 ± 0.06 at end of operation. Cerebral hemoglobin oxygen saturation decreased from 87% ± 4% at the start to 75% ± 5% at end of operation. This had not recovered by 12 (74% ± 4%) or 24 hours (73% ± 3%) postoperatively. Conclusions: This preliminary study suggests that thoracoscopic repair of CDH and EA/TOF may be associated with acidosis and decreased cSO₂. The effects of these phenomena on future brain development are unknown. [ABSTRACT FROM AUTHOR]