This CT scan, taken 22 days after<unk>  with major chest trauma, shows that the<unk>  has completely resolved.<unk>  usually resolves itself without causing permanent complications; however it may also have long-term ill effects on respiratory function. Most<unk> s resolve in five to seven days after the injury. Signs detectable by radiography are usually gone within 10 days after the injury—when they are not, other conditions, such as pneumonia, are the likely cause. Chronic lung disease correlates with the size of the<unk>  and can interfere with an individual's ability to return to work. Fibrosis of the lungs can occur, resulting in dyspnea (shortness of breath), low blood oxygenation, and reduced functional residual capacity for as long as six years after the injury. As late as four years post-injury, decreased functional residual capacity has been found in most<unk>  patients studied. During the six months after<unk> , up to 90% of people suffer difficulty breathing. In some cases, dyspnea persists for an indefinite period.<unk>  can also permanently reduce the compliance of the lungs. Complications A chest X-ray showing acute respiratory distress syndrome<unk>  can result in respiratory failure—about half of such cases occur within a few hours of the initial trauma. Other severe complications, including infections and acute respiratory distress syndrome (ARDS) occur in up to half of cases. Elderly people and those who have heart, lung, or kidney disease prior to the injury are more likely to stay longer in hospital and have complications from the injury. Complications occur in 55% of people with heart or lung disease and 13% of those without. Of people with<unk>  alone, 17% develop ARDS, while 78% of people with at least two additional injuries develop the condition. A larger<unk>  is associated with an increased risk. In one study, 82% of people with 20% or more of the lung volume affected developed ARDS, while only 22% of people with less than 20% did so. Pneumonia, another potential complication, develops in as many as 20% of people with<unk> . Contused lungs are less able to remove bacteria than uninjured lungs, predisposing them to infection. Intubation and mechanical ventilation further increase the risk of developing pneumonia; the tube is passed through the nose or mouth into the airways, potentially tracking bacteria from the mouth or sinuses into them. Also, intubation prevents coughing, which would clear bacteria-laden secretions from the airways, and secretions pool near the tube's cuff and allow bacteria to grow. The sooner the endotracheal tube is removed, the lower the risk of pneumonia, but if it is removed too early and has to be put back in, the risk of pneumonia rises. People who are at risk for pulmonary aspiration (e.g. those with lowered level of consciousness due to head injuries) are especially likely to get pneumonia. As with ARDS, the chances of developing pneumonia increase with the size of the<unk> . Children and adults have been found to have similar rates of complication with pneumonia and ARDS. Associated injuries Severe<unk>  with pneumothorax and hemothorax following severe chest trauma A large amount of force is required to cause<unk> ; a person injured with such force is likely to have other types of injuries as well. In fact,<unk>  can be used to gauge the severity of trauma. Up to three quarters of cases are accompanied by other chest injuries, the most common of these being hemothorax and pneumothorax. Flail chest is usually associated with significant<unk> , and the<unk> , rather than the chest wall injury, is often the main cause of respiratory failure in people with these injuries. Other indications of thoracic trauma may be associated, including fracture of the sternum and bruising of the chest wall. Over half of fractures of the scapula are associated with<unk> . The<unk>  is frequently found underlying fracture sites. When accompanied by a fracture, it is usually concentrated into a specific location—the<unk>  is more diffuse when there is no fracture. Pulmonary lacerations may result from the same blunt or penetrating forces that cause<unk> . Lacerations can result in pulmonary hematomas; these are reported to develop in 4–11% of<unk> s.
Pulmonary contusion
Hemothorax
Pulmonary hematoma
Diaphragmatic rupture
Urinothorax
Hemopneumothorax
Hydropneumothorax
Flail chest