What is the correct action for an unresponsive casualty without a pulse?

Initiating Cardiopulmonary Resuscitation (CPR) is the critical and immediate response for an unresponsive casualty without a pulse. This action is vital as it serves to maintain blood circulation and provide oxygen to the brain and other vital organs, increasing the chance of survival until advanced medical help arrives.

During cardiac arrest, the heart is not pumping blood effectively, and immediate CPR can help sustain life by preserving some level of cerebral and myocardial perfusion. The focus is on chest compressions, which are crucial in enabling the heart’s blood flow through mechanical means during this life-threatening situation. Additionally, CPR protocols recommend that rescue breaths be incorporated after a set of compressions if trained to do so.

The other options are not suitable responses. Waiting for emergency services to arrive is not an option because time is critical in these situations; every minute without circulation decreases the chances of survival. Administering epinephrine is not appropriate in this scenario as it is typically used in advanced life support situations and does not replace the immediate need for CPR. Checking for signs of life every few minutes delays necessary action and can result in fatal consequences. Therefore, the importance of starting CPR immediately cannot be overstated for an unresponsive casualty without a pulse.