Anesthetic considerations in a child with unrepaired D-transposition of great arteries undergoing noncardiac surgery

D-transposition of great arteries (D-TGA) is the most common cyanotic congenital heart disease diagnosed at birth. There is ventriculoarterial discordance leading to parallel circulation. The postnatal survival depends on intercirculatory mixing of oxygenated and deoxygenated blood at various levels through atrial septal defect, ventricular septal defect or patent ductus arteriosus. The anesthesiologist must have an understanding of concepts of shunting and other long-term consequences of transposition of great arteries (TGA) in order to tailor the anesthetic technique to optimize the hemodynamic variables and oxygenation in the perioperative period. The preoperative evaluation includes echocardiography to delineate the type of TGA, associated lesions and extent and direction of shunts. Oxygen saturation is influenced by the ratio of pulmonary vascular resistance (PVR) to systemic vascular resistance. Thus, care should be taken to avoid an increase in PVR which can lead to decreased pulmonary blood flow leading to hypoxia. We report a case of an 8-year-old child with unrepaired D-TGA, who presented to us for craniotomy for drainage of brain abscess.