Upon finding an unresponsive adult in the waiting room, what initial action should be taken to check for responsiveness?

Using the "shout-tap-shout" sequence is the correct initial action to check for responsiveness in an unresponsive adult. This method involves first shouting to gain the individual's attention and observe any response. If there is no response, the next step is to gently tap the individual on the shoulder or shake them while repeating calls for their attention. This sequence helps assess whether the person is responsive without immediately moving or intervening in a way that might disturb a potential injury or condition.

It is essential to establish whether the adult is responsive before proceeding with further actions such as calling for help or initiating CPR. The "shout-tap-shout" method is a quick and efficient way to determine a person's condition, which is crucial for deciding the next steps in care quickly.

While obtaining additional help and moving the patient are important aspects of emergency response, they should follow the initial assessment of responsiveness. Initiating chest compressions without first determining if the person is unresponsive could result in unnecessary and premature intervention. Therefore, the "shout-tap-shout" sequence is the appropriate first action in this scenario.