When pulmonary contusion is suspected, CXR is the imaging modality of choice ( Fig 115.4 ) However, the contusion itself may not be visible on CXR for to hours after the injury, and even then, false-negative rates of up to 33% have been reported Although more sensitive than CXR in detecting pulmonary contusion, a chest CT scan is usually unnecessary unless a significant injury to the vasculature is suspected, as management will depend on the clinical condition of the patient and not the radiographic size of the contusion Treatment of pulmonary contusion is supportive If required, supplemental oxygen should be administered If the patient cannot maintain oxygenation despite passive supplemental oxygen delivery, endotracheal intubation and mechanical ventilation with positive pressure is the treatment of choice Fluid restriction is helpful to avoid exacerbation of pulmonary edema, though must be balanced against the fluid needs arising from concurrent injuries to other organ systems and shock in the severely injured child Patients may require high inflation pressures to maintain adequate oxygenation, which combined with injury to the lung leads to high risk of barotrauma and pneumothorax Disposition Due to risk of progression of symptoms and need for increasing respiratory support, all patients with pulmonary contusion should be admitted for observation Given the low sensitivity of CXR for pulmonary contusion, children with significant chest pain or shortness of breath or an unexplained oxygen requirement after blunt chest trauma should also be admitted even if chest imaging is normal Admission to an intensive care unit is appropriate for patients with concerning vital signs, a significant oxygen requirement, respiratory distress, or who otherwise appear to be at high risk of progressing to require mechanical ventilation BLUNT CARDIAC INJURIES CLINICAL PEARLS AND PITFALLS