The Blalock–Thomas–Taussig shunt (commonly called the Blalock–Taussig shunt) is a surgical procedure used to increase pulmonary blood flow for palliation in duct dependent cyanotic heart defects like pulmonary atresia, which are common causes of blue baby syndrome. In modern surgery, this procedure is temporarily used to direct blood flow to the lungs and relieve cyanosis while the infant is waiting for corrective or palliative surgery.