Secondary Hemodialysis Catheter Malposition Associated with Azygos Vein Dilation in the Setting of Acute Hemodynamic Changes

ABSTRACT We report a case of secondary hemodialysis catheter migration into the azygos vein in a 53-year-old critically ill woman. Despite correct initial catheter placement under fluoroscopy, the catheter tip migrated into the azygos arch 4 hours later. Retrospective imaging revealed that the azygos arch had dilated from 3.4 mm to 9.2 mm, likely associated with high positive-pressure ventilation and fluid overload. This case suggests that azygos vein dilation during various procedures may contribute to catheter malposition. These findings indicate that in critically ill patients, initial imaging alone may be insufficient for accurate catheter placement, suggesting the importance of continuous post-procedural monitoring.