The radiograph demonstrated malposition of the catheter, with one lumen in the azygos vein and the second in the right brachiocephalic vein (Fig. 1A). Interventional radiology was consulted for catheter replacement to allow hemodialysis to be safely performed (Fig. 1B).

Hemodialysis catheters have a 1-year complication rate of 30% [1]. Complications can include thrombosis, infection, dislodgment, and stenosis. Central venous catheters can also migrate with patient position; therefore, initial correct placement does not ensure fixed placement in the original location. While the right internal jugular vein (IJV) is the preferred insertion site, the left IJV may be used when the right is contraindicated [2]. Risk factors for displacement include left IJV placement (due to increased length and reduced entry angle from the left brachiocephalic vein), insufficient insertion depth, and increased right atrial pressure, which dilates the azygos vein [3,4]. Recognizing azygos vein displacement is essential due to increased risk of thrombus, vessel perforation, and stenosis [5]. The azygos vein runs along the right thoracic vertebra and branches upward and medially into the superior vena cava. This migration can be identified on a chest radiograph as a catheter that runs obliquely across the midline and then follows a caudal and medial course or abrupt bending of the catheter tip [6]. Once identified, repositioning is necessary before using the catheter for hemodialysis.