What should be done for a casualty showing initial signs of tension pneumothorax?

When a casualty presents with initial signs of tension pneumothorax, the most critical and immediate intervention is to insert a large bore needle to decompress the pleural sac. Tension pneumothorax occurs when air enters the pleural space and cannot escape, leading to increased pressure in the chest cavity. This pressure can collapse the lung on the affected side and severely restrict blood flow to the heart, creating a life-threatening situation.

By inserting a large bore needle into the pleural space, typically in the second intercostal space at the midclavicular line on the affected side, you allow the trapped air to escape. This rapid decompression can relieve pressure, restore lung function, and improve oxygenation, significantly increasing the chances of survival.

Other options, while important in different medical situations, do not address the immediate need to relieve the pressure from the pleural space associated with tension pneumothorax. For example, administering oxygen can be helpful for many respiratory issues but does not directly treat the underlying cause of tension pneumothorax. Performing CPR is vital when there is no heartbeat, but in the case of tension pneumothorax, addressing the pneumothorax urgently should be the first priority. Covering a wound with a