A 28-year-old female develops dyspnea after thoracic trauma and shows crackles in lung sounds. Vital signs indicate a low SpO2. What action should be taken?

Applying oxygen via a non-rebreather mask and transporting the patient emergently is the most appropriate action in this scenario. The patient's dyspnea following thoracic trauma and the presence of crackles in the lung sounds suggest a potential lung injury, such as a pneumothorax or pulmonary contusion, which can lead to impaired gas exchange and low oxygen saturation levels.

Administering oxygen via a non-rebreather mask allows for the highest concentration of oxygen delivery, which is crucial for treating hypoxia. Immediate transport is necessary to ensure that the patient receives further evaluation and treatment in a timely manner, as delays could worsen their condition.

This approach addresses both the emergency nature of the situation and the specific symptoms presented. Providing supplemental oxygen and arranging for rapid transport can significantly improve the patient's chances of recovery and address the critical issue of low SpO2.