Mediastinal hematoma caused by central venous catheterization: a rare cause of obscure blood loss.

Gastrointestinal hemorrhage, internal bleeding beyond the gastrointestinal tract and hemolysis are common causes of blood loss in intensive care unit patients. However, mediastinal hematoma is a rare cause of blood loss and is not usually detected. Here, we report a patient who developed a mediastinal hematoma resulting from central venous catheterization who presented with obscure blood loss refractory to blood transfusion. A mediastinal hematoma should be considered in the presence of obscure blood loss in patients with catheter placement.