The pulmonary parenchymal blood flow is a low pressure system and the bleeding should spontaneously resolve. Continued bleeding is usually from an intercostal vessel or internal mammary artery. Lesser degrees of hemorrhage should spontaneously stop. Steering wheel injury causes transverse tracheal injury, shearing of the right mainstem bronchus, or rupture of the membranous trachea. The patient presents with mediastinal and cervical emphysema, a massive air leak, and hemoptysis.
Repair is indicated.
Bronchoscopy is diagnostic. The injury usually occurs at the ligamentum arteriosum distal to the left subclavian artery origin. Occasionally chronic aneurysms form in those patients not repaired at the time of the initial injury. Other radiographic signs include the loss of the aortic knob. Patients may also need evaluation based on mechanism of injury alone.