Hydromediastinum after aberrant central venous catheter placement.

After central venous catheter placement via the right subclavian route, a hydromediastinum was produced. Aberrant placement of the catheter was undiscovered for 13-1/2 hours despite clinical and radiographic signs. Careful interview of the patient and analysis of postcatheterization chest radiographs are imperative in order to avoid catastrophic consequences of aberrant catheter placement.