label: Failure to increase oxygen saturation on hyperoxia test
label_lc: failure to increase oxygen saturation on hyperoxia test
description: "Hyperoxia test is the initial method to distinguish critical congenital heart disease (CCHD) from pulmonary disease. The test consists in measuring an arterial blood gas at room air and 100% inspired oxygen after 10 minutes. Neonates with congenital heart disease are usually not able to increase PaO2 above 100 mm Hg during 100% oxygen administration. In patients with pulmonary disease, PaO2 generally increased greater than or equal to 100 mm Hg with 100% oxygen as ventilation-perfusion discrepancies are overcome. A positive result indicates the cardiac origin and further cardiac workup is indicated to rule out CCHD."