A rare case of central venous catheter malpositioning in polytraumatic patient not recognized by chest x-ray.

Central venous catheter (CVC) insertion is one of the most widely practiced procedures in the intensive care unit (ICU) and the most common complications of this procedure are pneumothorax, artery puncture and malposition. The location of malpositioned subclavian vein catheters may include the ipsilateral internal jugular vein, the controlateral brachiocephalic vein and loop formation. The cannulation of tributaries of the main intra-thoracic vein is a rare complication (1). A 40-year-old man was admitted to our ICU for polytrauma following an eight meter fall into a manhole left accidentally uncovered. He reported a thoracic trauma and pelvic fractures. The patient was sedated, intubated and mechanically ventilated and a CVC was inserted through the left subclavian vein without complications. No resistance was felt during insertion and venous blood was aspirated through the lumen without signs of obstruction. A chest x-ray was performed to verify the correct position of the central line and no complication was recognized (Fig. 1). A chest CT scan was then performed to control the lung contusion and this revealed that the CVC tip was controlaterally inserted into the right internal thoracic vein (Fig. 2). Thus, the catheter was removed and inserted into the right internal jugular vein. Most of the cases reported in literature associate this complication with left internal jugular vein cannulation with the catether tip into the ipsilateral internal thoracic vein. Other possibilities are azygos vein or pericardiophrenic vein cannulation. Finally, some congenital variant could be present such as the persistence of the left superior vena cava (2). The peculiarity of our case (the first of this kind) is left subclavian vein cannulation with the catheter tip into the controlateral internal thoracic vein. A predisposition of this complication in patients with portal hypertension has been reported because of engorgement of the venous system (3). Patients can be symptomatic or asymptomatic. Symptoms include chest pain, especially during hyperosmolar solution infusion (e.g., total parenteral nutrition) and during high flow infusion rate. Other complications may include venous thrombosis or thrombophlebitis, extravasation of infusate, pleural effusion, pulmonary edema and chest wall abscess (4). Central venous pressure (CVP) waveform analysis could help us suspect this rare complication, by showing flattened waves instead of the typical a, c, v, x, y waves (5). Conclusion: The chest x-ray cannot always demonstrate CVC malpositioning since the catheter can be projected into the vena cava profile (2). We must suspect this complication in case of difficult catheter insertion, typical symptoms or altered CVP waveform. In these cases other diagnostic tests for correct catheter placement should be considered if chest x-ray is negative.