C52-36 Right Internal Mammary Artery Injury and Mediastinal Hematoma After Subclavian Central Venous Catheterization

Introduction Central venous catheters (CVC) are integral to the medical intensive care unit (MICU), with over 5 million CVCs inserted every year in the United States. Arterial puncture, hematoma, and pneumothorax are the most common mechanical complications with CVC placement2. Here, we discuss a case of right internal mammary artery (RIMA) injury following a subclavian CVC attempt. Case report A 71-year-old woman presented for acute hypoxic respiratory failure and encephalopathy needing intubation. She was on apixaban for atrial fibrillation and clopidogrel due to a prior middle cerebral artery stroke. A right subclavian CVC placement was attempted in the ER, which was unsuccessful due to the inability to pass the guidewire. A post-procedure chest X-ray (CXR) did not show a pneumothorax. In the MICU, a left internal jugular (IJ) CVC was placed. A few hours after admission, worsening hypoxia with elevated peak pressures on the ventilator were noted. A repeat CXR showed right pneumothorax, and a right-sided chest tube was placed. 12 hours after admission, she developed shock with labs showing a drop in hemoglobin from 8.7 g/ dL to 5.4 g/dL. Massive transfusion protocol (MTP) was initiated, and once she was stabilized, a computed tomography angiography (CTA) of the chest showed a RIMA pseudoaneurysm (Figure 1) and a large mediastinal hematoma (Figure 2). She underwent an emergent RIMA embolization by interventional radiology (IR), and hemostasis was achieved. Discussion This case highlights the potential complications associated with subclavian line placement, including the rare occurrence of IMA injury and mediastinal hematoma. While subclavian artery catheterization as a complication of subclavian CVC has been described at a rate of 1-3%, vascular injury of the branch arteries, like IMA, remains exceedingly rare.1 In literature, most IMA injuries present as expanding chest wall or mediastinal hematomas, pseudoaneurysms, or hemothorax, often requiring endovascular embolization for definitive control1. Another interesting aspect of our case was the delayed development of pneumothorax. Small pleural or parenchymal injuries can create a slow air leak, leading to pneumothorax hours later, especially if patients are on positive pressure ventilation. While these complications are rare, they can often be life-threatening. Therefore, physicians need to be vigilant as early recognition and treatment can lead to improved patient outcomes. This abstract is funded by: None