(A) Percentage of oxyhemoglobin (SpO2) as a function of arterial oxygen saturation (SaO2) and race. (B) SpO2 as a function of SaO2 and diastolic runoff lesions. (C) SpO2 as a function of SaO2, race, and diastolic runoff lesions. (D) Patient demographics. AA, African American; BSA, body surface area; BTTS, Blalock-Thomas-Taussig shunt; cath, catheterization; Hgb, hemoglobin; PA, pulmonary artery; PDA, patent ductus arteriosus; SaO2, arterial oxygen saturation; SpO2, percentage of oxyhemoglobin.