A central line is an intravascular device or catheter that terminates at or close to the heart in one of the great vessels, and is used to provide temporary or long-term vascular access for the delivery of pharmacotherapy, total parenteral nutrition and/or regular blood sampling. 1 A 58-year-old woman presented to the emergency department with a 1-week history of malaise, anorexia, bilateral flank pain and decreased colostomy output, on a background of Crohn's disease with multiple resections.On examination she appeared cachectic and distressed, but alert and orientated. She was febrile (38.4°C), normotensive (systolic 115, diastolic 63 mmHg), tachypnoeic (20/min), but saturating well (97%) on ambient air. Biochemical investigations revealed an acidosis (pH 7.10), acute kidney injury (AKI) (creatinine 247 μmol/L), a normal white cell count (9.3 × 10^9/L) and elevated C-reactive protein (182.9 mg/L). She was prepared for intensive care unit admission for ongoing management.A left internal jugular three lumen central venous catheter (CVC) was inserted utilizing ultrasound to minimize complications. Two passes were required for insertion with a note of 'difficulties passing the wire beyond valve'. A post-insertion chest radiograph (CXR) was performed to confirm the CVC's position (Fig. 1). This revealed that the CVC was not in the desired location (cavo-atrial junction) and that it may have entered the descending aorta. A lateral CXR was performed revealing the CVC taking a posterior course in the left hemithorax (Fig. 2). The CVC was flushed and aspirated without any documented difficulty. Blood was aspirated from the CVC for blood gas analysis and results suggested venous placement (pO 2 52 mmHg, pCO2 43 mmHg) when compared with blood gas analysis from a peripheral arterial sample (pO2 116 mmHg, pCO2 42 mmhg). Connection of the CVC to a transducer produced a venous trace. Because of AKI a contrast study (computed tomography (CT) or venogram) was avoided to minimize renal insult. A non-contrast CT scan was performed, that mapped the CVC travelling through the left internal jugular vein, into the left innominate vein and down one of its inferior tributaries -the left superior intercostal vein (SIV) (Fig. 3). The left SIV is responsible for draining the superior left posterior hemithorax and is a component of the azygous venous system. It is formed by the union of the second to fourth left posterior intercostal veins and courses superiorly to the left of the midline, arches superiorly lateral to the aortic arch to drain into the left innominate vein. 2 The decision was made to remove the CVC, and was performed successfully without negative sequalae.Insertion of a CVC should be within a large-calibre vein with sufficient flow to tolerate infusion for example subclavian, brachiocephalic, superior vena cava. 3 However, malposition of the CVC can occur. Review of the literature resulted in three previous reports of a left internal jugular vein CVC being introduced into the left SIV. 3-5 The use of a post-insertion CXR fo...