What should be done first if ventricular fibrillation is confirmed?

When ventricular fibrillation is confirmed, the most critical immediate action is to start CPR. This is because ventricular fibrillation results in a lack of effective cardiac output, which leads to inadequate blood flow to vital organs. Initiating CPR immediately helps maintain some level of circulation, providing essential oxygen to the brain and other organs while waiting for advanced medical interventions, such as defibrillation, to restore a normal heart rhythm.

The urgency of this action cannot be overstated; without immediate CPR, the probability of survival decreases significantly within minutes. Other actions, such as attaching a blood pressure monitor, administering oral medications, or assessing the patient's history, are important in the broader context of managing a cardiac emergency, but they cannot replace the need for immediate resuscitation efforts like CPR. These other actions can follow once essential life-support measures are underway.