When treating a casualty with a chest wound, if the casualty does not want to sit up, how should he be positioned?

Positioning a casualty with a chest wound correctly is critical for their safety and comfort, especially if they do not want to sit up. The preferred position in such a scenario is on their side with the wounded side facing down. This positioning helps to avoid further injury to the wound and allows any air that may have entered the pleural space (creating a risk of a pneumothorax) to escape more easily. It also minimizes the risk of aspiration if the casualty vomits and can help facilitate breathing by allowing gravity to assist with lung expansion.

In contrast, other positions, such as lying flat on their back or stomach, could exacerbate breathing difficulties and may cause further discomfort or injury to the chest area. Sitting upright may also increase the risk of stress on the wound and should be avoided if the casualty prefers to lie down. Thus, keeping the casualty on their side with the injured side down is both a protective measure and serves to alleviate discomfort, making it the best choice.