A 27 year old patient involved in a motor vehicle accident is bought to the emergency room alert, cooperative, and hemodynamically stable.  The patient's respiratory rate is 24/minute and the arterial blood gas shows pH 7.49, pO2 95 mmHg, pCO2 30 mmHg.  The chest radiograph obtained in the emergency room shows pneumomediastinum with no pneumothorax.  The initial management of this injury should include

A.  bronchoscopy.

B.  intubation.

C.  observation.

D.  thoracoscopy.

E.  tube thoracostomy.

 

Answer A

Pneumomediastinum is the presence of air or gas in the mediastinum.  The most common sites of airway injury from blunt trauma are the mainstem bronchi within 2.5 cm of the carina and the middle lobe bronchus.  These injuries are best evaluated using fiberoptic bronchoscopy.  Esophageal perforations are an unlikely cause of peumomediastinum after blunt trauma.  In patients with pre-existing esophageal disease or other risk factors for esophageal perforation, an esophagogram with water-soluble medium can be obtained when vital signs have been stabilized. 

Although the evaluation of pneumomediastinum may not take priority over serious co-existing injuries, observation alone is not appropriate after significant blunt chest trauma.  Thoracoscopy plays no role in the evaluation of pneumomediastinum after chest trauma.  With no apparent pneumothorax or hemothorax on chest radiograph, there is no indication for tube thoracostomy.  The need for a chest tube, however, should be continuously reassessed and considered with any evidence of hemodynamic decompensation or if positive pressure ventilation is required.