Inadvertent insertion of a subclavian central venous catheter into the pulmonary artery through a Blalock-Taussig shunt: a rare complication of a common procedure.

Central venous catheter (CVC) insertion is a common procedure providing direct access to the central venous system. Potential mechanical, infectious, and embolic complications could occur. Malpositioning into the pulmonary artery is a very rare complication. A modified Blalock-Taussig shunt (MBTS), anatomically positioned between the subclavian and the pulmonary arteries and adjacent to the right internal jugular vein, is the most common procedure performed in children with complex congenital heart disease (CHD) to enhance pulmonary artery blood flow. Here, we present an infant with a complex CHD and an MBTS in whom a CVC was placed under ultrasound guidance. The misplacement of the CVC was suspected due to deviation of the CVC in chest radiography, elevated PvO2 levels obtained from the CVC, and an increased central venous pressure recorded via the CVC. Cardiac catheterization confirmed that the CVC tip was located in the pulmonary artery, having been inserted through MBTS. The catheter likely traversed the right carotid artery, subclavian artery, Blalock-Taussig (BT) shunt, and pulmonary artery.