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

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 (cSO(2)), arterial blood gases, and carbon dioxide (CO(2)) absorption.

METHODS

Eight infants underwent thoracoscopy (6 CDH and 2 EA/TOF). Serial arterial blood gases were taken. Regional cSO(2) was measured using near-infrared spectroscopy. Absorption of insufflated CO(2) was calculated from exhaled (13)CO(2)/(12)CO(2) ratio measured by mass spectrometry.

RESULTS

CO(2) absorption increased during thoracoscopy with a maximum 29% ± 6% of exhaled CO(2) 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 cSO(2). The effects of these phenomena on future brain development are unknown.