What Is a Pulmonary Contusion?

Lung contusion is a common lung parenchymal injury, mostly caused by blunt blunt injuries, such as car accidents, impacts, crushes, and falls. Occurrence rate is about 30% to 75% of blunt chest injury, but it is often overlooked or missed due to lack of understanding of it, insensitivity of examination techniques or masking by other chest injuries.

Overview of lung contusions

Lung contusion is a common lung parenchymal injury, mostly caused by blunt blunt injuries, such as car accidents, impacts, crushes, and falls. Occurrence rate is about 30% to 75% of blunt chest injury, but it is often overlooked or missed due to lack of understanding of it, insensitivity of examination techniques or masking by other chest injuries.

Pathogenesis of lung contusion

The pathogenesis of lung contusion is still not completely clear, and most are thought to be similar to lung blast injuries due to strong high pressure waves. When strong violence acts on the chest wall, the volume of the chest cavity is reduced, the increased intra-thoracic pressure forces the lungs, causing pulmonary parenchymal bleeding and edema; when the external force is eliminated, the deformed thorax bounces back, which can lead to a moment of negative chest pressure Additional damage to the original damaged area. The main pathological changes are alveolar and capillary damage with interstitial and alveolar blood leakage and interstitial pulmonary edema, which reduces the pulmonary parenchyma and increases the extravascular water content, dysfunction of ventilation and ventilation, pulmonary arterial pressure and pulmonary circulation Increased resistance production. Pathological changes developed progressively 12 to 24 hours after injury. Lung contusion is often accompanied by other injuries, such as fractures of the chest wall, flail chest, hemothorax, pneumothorax, and heart and pericardial injuries.

Clinical manifestations of pulmonary contusion

Because of the severity and extent of the lung contusion, clinical manifestations vary widely. Mild cases include chest pain, chest tightness, shortness of breath, cough, and blood sputum. There are scattered rales on auscultation. There are patchy shadows on X-ray chest radiographs (often reported as traumatic wet lungs), which can be completely absorbed within 1 to 2 days. Blood gas can be normal. Some people call it a concussion. In severe cases, there are obvious dyspnea, cyanosis, bloody foamy sputum, tachycardia, and decreased blood pressure. On auscultation, there are extensive rales, the breathing sounds are weakened to disappear, or the breathing is cast. Arterial blood gas analysis with hypoxemia has a reference value before the chest radiograph can be displayed. X-ray chest radiography is an important method to diagnose lung contusion. The change occurs in about 70% of cases within 1 hour after injury, and 30% of cases can be delayed to 4 to 6 hours after injury. The range can range from a small confined area to one or both sides, and the degree can be infiltrated, diffuse or local. The spots are fused and infiltrated, resulting in diffuse single or double lung infiltration or consolidation of shadows. After treatment, absorption generally begins 2 to 3 days after injury, and complete absorption takes more than 2 to 3 weeks. In recent years, through a series of CT examinations, new pathological views have been proposed for pulmonary contusions. The contusions shown on plain X-ray films are manifested on the CT film as a pulmonary parenchyma and a piece of alveolar hemorrhage surrounding the laceration without interstitial injury.

Lung contusion treatment

Mild lung contusion should also be treated. Severe lung contusion is the most common cause of acute respiratory failure after chest injury. The treatment is to maintain respiratory and circulatory functions and to properly handle combined injuries. Flail chests often have lung contusions of varying degrees. The pathophysiological changes depend to a large extent on lung contusions, and mechanical ventilation should be given promptly when there are signs of acute respiratory failure. At present, the application of corticosteroids has not been emphasized as in the past. For those with low blood volume shock, blood volume must be replenished in a timely manner, and the ratio of crystal and colloid fluid must be properly matched to maintain normal colloid osmotic pressure and total osmotic pressure. Negative liquid balance, 1600 to 1800 ml per day.