What should be the EMS response to a patient with a cardiac arrest?

The appropriate EMS response to a patient experiencing cardiac arrest is to initiate CPR and use an AED (Automated External Defibrillator) as soon as possible. This approach is critical because immediate CPR helps to maintain blood circulation to vital organs, particularly the brain and heart, and increases the chances of survival until advanced medical help arrives.

Using an AED promptly is also essential, as it can deliver a shock to help restore a normal heart rhythm in cases of certain types of cardiac arrest, such as ventricular fibrillation or pulseless ventricular tachycardia. The combination of high-quality CPR and rapid defibrillation significantly improves patient outcomes.

The other options do not align with the critical need for immediate action in a cardiac arrest situation. Reassuring a patient is not applicable here, as a patient in cardiac arrest is unresponsive and requires immediate medical intervention. Waiting for advanced life support to arrive before acting delays the necessary treatment and is counterproductive in a life-threatening emergency. Administering medications immediately can be part of advanced care, but such measures should only be undertaken after establishing basic life support measures like CPR and defibrillation have been initiated.