Do you know how to perform CPR?
This actually can save someones life.
Basic Life Support helps buy the patient time until specialised help arrives at the scene.
They can actually defibrillate the heart and shock the life-threathening arrythmia.
But breain tissue damages after 6 minutes of cardiac arrest. So it is absolutely critical that circulation is maintained until those first minutes.
Advanced life support has absoluetlo no meaning without basic cpr.
The guidelines say your first must shout and gently shake the patient. After the patient stays uncunscious check if tehere is still breathing?
When no breathing is present call the emergency dispatch and ask for an ambulance and say your are in a CPR-situation.