Critical anterior mediastinal hematoma without internal mammary artery injury caused by cardiopulmonary resuscitation: A case report.

Background: Massive anterior mediastinal hematoma due to chest compression during cardiopulmonary resuscitation is often caused by internal mammary artery injury. However, critical massive anterior mediastinal hematoma without damage to major blood vessels is extremely rare. We report a case of life-threatening anterior mediastinal hematoma without internal mammary artery injury during extracorporeal cardiopulmonary resuscitation.

Case presentation: A 70-year-old man was transferred to our emergency department because of ventricular fibrillation arrest. Manual chest compressions and venoarterial extracorporeal membrane oxygenation were applied in the angiography room. Acute myocardial infarction was diagnosed, and percutaneous coronary intervention with stent placement was performed. Despite the establishment of venoarterial extracorporeal membrane oxygenation flow, the hemodynamics were unstable. Computed tomography revealed a massive anterior mediastinal hematoma compressing the right heart system and causing obstructive shock. Although local incision and anterior mediastinal hematoma drainage were tried for resolving obstructive shock, the patient's anemia did not improve, and there was still continuous hemorrhaging from the drainage tube. A median thoracotomy was then performed. There was no injury of the main trunk of the internal mammary artery but only hemorrhaging from the sternal fracture site. The patient's hemodynamics and anemia improved after hemostasis and gauze packing. Re-thoracotomy for gauze removal and sternal closure was performed three days post-hospitalization.

Conclusions: It is important to consider hemorrhaging and unstable hemodynamics in patients who receive extracorporeal cardiopulmonary resuscitation. Therefore, a thoracotomy may take precedence over intravascular treatment for restoring hemostasis when there is no information regarding the bleeding site, such as the presence of extravasation.