What’s the CPR?   
      CPR=cardiopulmonary resuscitation
      When the heart stops, the absence of oxygenated blood can cause permanent brain damage in only a few minutes.
    Death will occur within approximately 8-10 minutes. The purpose of CPR is to get a partial flow of oxygenated blood to the brain and heart. This is evident by the fact that CPR alone, is unlikely to restart the heart. (CPR may succeed in inducing a heart rhythm that a defibrillator can shock into a proper rhythm).
Timeline of CPR Effectiveness Versus Brain Damage
0 - 4 minutes: Brain damage is unlikely
4 - 6 minutes: Brain damage is possible
6 - 10 minutes: Brain damage is probable
Over 10 minutes: Probable brain death
Child CPR is Summarized as: DRS-ABCD:
    The DRS part stands for what to do before you begin CPR. While the ABCD part stands for what to do during CPR.
Danger
    Before you begin the CPR process, you should ensure that you and the victim are safe from danger. If there's no danger, you move on to the next step.
Response
Next, you should check if the child is conscious or not. You can tap them gently on their shoulders, or tickle them while asking “Are You OK?”.
Then, see if the child moves or makes a noise. If they are unconscious and don't respond, then move on to the next step.
Do not move the child as they may have a spinal or neck injury. Instead, leave them on the surface where they are found. Do not attempt to pick them up.
Send for help
To get help, you’re going to dial 120, and tell them clearly and calmly where you are and what the situation is.
Due to the language barrier, calling 120 may not be the quickest option. This is especially true if there is a colleague or even another student nearby. Do whatever you need to do, to get help. Just don't delay starting CPR.
Beginning CPR (ABCD)
Airway
Open the airway. Lift up the chin with one hand, and at the same time, push down on the forehead with the other hand.
Keep the head tilted and chin lifted towards the ceiling as this position can keep the airway open as helps lift the tongue.
If there’s anything in the child's mouth, you can gently roll them on their side to help remove the object. Then, gently roll them onto their original position.
Opening the airway is the top priority for giving CPR to a child, as it gives them the highest possibility of breathing.
Breathing
While holding the airway open, look, listen, and feel for breaths.
Place your ear close to the child's nose and mouth. Watch for any chest movement.
Feel for breath on your cheek. If you notice that the child has normal breathing, but isn't responding to stimuli, this means they are unconscious.
In this case, gently roll the child onto their side, which is called the “recovery position”. This position prevents them from choking on their own vomit.
If the child is breathing shallowly, abnormally (gasping, off-rhythm), or isn't breathing at all, and begins to change color, then you need to start compressions.
Compressions
Remove the child's shirt to expose their chest, and place one hand just below the nipple line (over the breastbone), and push down about 1/3 of their chest diameter, in a rhythm. Your rhythm should be 100 compressions per minute, and give two breaths every 30 compressions.
While breathing in (at every 30 compressions), pinch the child's nose and consider the size of their lungs. If the child is half your size, then use half your breath.
Only stop giving CPR when the child begins to respond. When they do, gently roll them onto their side and watch them closely. Make sure that help is on the way. You can also stop giving CPR when you feel too exhausted to continue, or when the ambulance takes over.
Defibrillator
Attach defibrillator to the child, if available.
A defibrillator (commonly an AED – Automatic External Defibrillator) is a device that measures the hearts rhythm and gives an electric shock to attempt to restart the heart at a normal rhythm.
Unlike the movies, a “defib” does not restart the heart. It simply shocks an off-rhythm heart back into a proper rhythm.