Pulmonary contusion is a type of lung injury that occurs when the lung tissue is bruised, usually due to blunt trauma, such as from a car accident or a fall. This injury can lead to bleeding and swelling in the lungs, which may impair breathing and oxygen exchange. Symptoms often include chest pain, difficulty breathing, and coughing up blood. Diagnosis typically involves imaging tests like a CT scan or X-ray to assess the extent of the injury. Treatment may include monitoring, oxygen therapy, and in severe cases, mechanical ventilation to support breathing while the lungs heal.