A 46 year old is brought in by EMS after a motor vehicle collision in which he was an unrestrained driver. Although he has no obvious injury to his head or neck, he complains of chest pain and appears very short of breath. His vital signs are: T 99.2 F, BP 85/57, HR 123, RR 36, SpO2 95% on non-rebreather. The CXR demostrates a tension pneumothorax. Required:
Which is the most appropriate next step in this men's care?