What is one of the first actions to take when assessing a casualty's airway?

Identifying obstructed airway signs is critical when assessing a casualty's airway because an obstructed airway can lead to immediate and life-threatening consequences. An individual who is unable to breathe effectively may be at risk of hypoxia, which can occur within minutes.

Therefore, the swift assessment of whether the airway is open and clear is paramount. This involves checking for visible signs of obstruction, such as the presence of foreign objects, blood, or swelling that could hinder normal airflow. If signs of an obstructed airway are identified, appropriate interventions such as the Heimlich maneuver or suctioning may be necessary to restore a clear airway.

Other actions, while important in a broader context of casualty assessment and care, do not address the immediate need to ensure that the airway is open and functioning as the first priority should be maintaining adequate oxygenation and ventilation.