The insertion of a central venous catheter (CVC) is a necessary procedure prior to pediatric cardiac surgery. Although CVC insertion is generally safe, the occurrence of complications, while infrequent, can include the rare combination of pneumothorax and hemothorax. This study reports a rare case of concurrent pneumothorax and hemothorax in a 5-year-old child with cardiac arrest after induction of anesthesia. A 5-year-old patient, eligible for either the Fontan procedure, suffered a cardiac arrest following CVC insertion. An echocardiogram, performed immediately, ruled out cardiac tamponade. However, the presence of both hemothorax and pneumothorax necessitated the insertion of a pigtail catheter and chest tube. In pediatric patients requiring CVC via the subclavian vein, it is prudent to establish peripheral venous access a priori. This precautionary measure ensures the availability of a conduit for fluid resuscitation, should the need arise.