X-Ray

Chest X-ray is the most common method used for diagnosis,[36] and may be used to confirm a diagnosis already made using clinical signs.[19] Consolidated areas appear white on an X-ray film.[41] Contusion is not typically restricted by the anatomical boundaries of the lobes or segments of the lung.[26][42][43] The X-ray appearance of pulmonary contusion is similar to that of aspiration,[31] and the presence of hemothorax or pneumothorax may obscure the contusion on a radiograph.[24] Signs of contusion that progress after 48 hours post-injury are likely to be actually due to aspiration, pneumonia, or ARDS.[10]
Although chest radiography is an important part of the diagnosis, it is often not sensitive enough to detect the condition early after the injury.[34] In a third of cases, pulmonary contusion is not visible on the first chest radiograph performed.[7] It takes an average of six hours for the characteristic white regions to show up on a chest X-ray, and the contusion may not become apparent for 48 hours.[7][26][42] When a pulmonary contusion is apparent in an X-ray, it suggests that the trauma to the chest was severe and that a CT scan might reveal other injuries that were missed with X-ray.[2]

Article 1

A pulmonary contusion (or lung contusion) is a contusion (bruise) of the lung, caused by chest trauma. As a result of damage to capillaries, blood and other fluids accumulate in the lung tissue. The excess fluid interferes with gas exchange, potentially leading to inadequate oxygen levels (hypoxia). Unlike pulmonary laceration, another type of lung injury, pulmonary contusion does not involve a cut or tear of the lung tissue.

A pulmonary contusion is usually caused directly by blunt trauma but can also result from explosion injuries or a shock wave associated with penetrating trauma. With the use of explosives during World Wars I and II, pulmonary contusion resulting from blasts gained recognition. In the 1960s its occurrence in civilians began to receive wider recognition, in which cases it is usually caused by traffic accidents. The use of seat belts and airbags reduces the risk to vehicle occupants.

Diagnosis is made by studying the cause of the injury, physical examination and chest radiography. Typical signs and symptoms include direct effects of the physical trauma, such as chest pain and coughing up blood, as well as signs that the body is not receiving enough oxygen, such as cyanosis. The contusion frequently heals on its own with supportive care. Often nothing more than supplemental oxygen and close monitoring is needed; however, intensive care may be required. For example, if breathing is severely compromised, mechanical ventilation may be necessary. Fluid replacement may be required to ensure adequate blood volume, but fluids are given carefully since fluid overload can worsen pulmonary edema, which may be lethal.

The severity ranges from mild to deadly—small contusions may have little or no impact on the patient's health—yet pulmonary contusion is the most common type of potentially lethal chest trauma. It occurs in 30–75% of severe chest injuries. With an estimated mortality rate of 14–40%, pulmonary contusion plays a key role in determining whether an individual will die or suffer serious ill effects as the result of trauma. Pulmonary contusion is usually accompanied by other injuries. Although associated injuries are often the cause of death, pulmonary contusion is thought to cause death directly in a quarter to half of cases. Children are at especially high risk for the injury because the relative flexibility of their bones prevents the chest wall from absorbing force from an impact, causing it to be transmitted instead to the lung. Pulmonary contusion is associated with complications including pneumonia and acute respiratory distress syndrome, and it can cause long-term respiratory disability.