What is the appropriate response if a patient is unresponsive and pulseless?

In a situation where a patient is unresponsive and pulseless, the priority is to initiate Cardiopulmonary Resuscitation (CPR) immediately. This response is critical because the patient is not breathing and has no pulse, indicating cardiac arrest. CPR serves two main purposes: it helps maintain blood flow to vital organs, particularly the brain and heart, and it provides a chance to restore normal heart rhythm when a defibrillator is available.

The other options, while important in different contexts, do not address the immediate need for circulation. Administering oxygen is unnecessary if the patient is not breathing and has no heartbeat, as oxygen cannot be effectively delivered without circulation. Checking the airway for obstruction is a vital step in assessing a non-breathing patient but becomes secondary to starting CPR, especially in an unresponsive and pulseless scenario. Positioning the patient on their side may be suitable in certain situations, particularly with a breathing but unconscious patient, but again, this is not appropriate when there is no pulse or respiration.

Starting CPR as soon as possible maximizes the chances of survival until advanced medical help can arrive.