When a casualty with tension pneumothorax is evacuated, how should they be positioned?

The appropriate position for a casualty with tension pneumothorax during evacuation is on the injured side with the catheter. This positioning can help facilitate drainage of air from the pleural space and assist in re-expanding the affected lung. By lying on the affected side, gravity aids in allowing trapped air to escape more easily through the catheter, which is critical in alleviating pressure and preventing further respiratory distress. This method also helps maintain airway patency and can improve oxygenation until further medical treatment is available.

In contrast, positioning the casualty on their back or sitting upright may not effectively address the pneumothorax, as these positions can maintain pressure in the thoracic cavity. Additionally, lying on the side opposite the injury does not assist in promoting drainage and may exacerbate respiratory difficulties, as the affected lung may be compressed further. Therefore, the most effective approach is to have the casualty positioned on the side with the catheter to support humane and proper medical care.