Right internal jugular and subclavian catheters should not cross the midline. Left  internal jugular and subclavian catheters should cross midline unless you have a left SVC.

A blood gas analysis was performed at the bedside. This confirmed an inadvertent cannulation of the carotid artery. This is a potentially devastating complication if not recognized quickly. If there is any doubt, the needle’s location can be alternately confirmed by pressure transduction. If a carotid artery is cannulated, vascular surgery should be consulted. Inadvertent dilation and cannulation of the carotid artery is associated with severe complications such as carotid thrombosis and acute stroke.

In this case, no CT was done and the catheter was removed without any complications.