You do not have to memorize the circulatory system. What is important is that you will understand the importance of blood circulation.
Basically blood carries nutrients and oxygen to all parts of body, including the Brain. The blood is being pumped by our heart. Therefore, if the heart stops, the brain will not receive oxygenated blood and in a few minutes, brain damage occurs.
Once damage, the brain cells cannot be repaired.
Therefore it is essential that CPR should be provided immediately once the Heart stops pumping. By providing external chest compression, blood circulation can be achieved. Providing ventilations or mouth to mouth to a victim can also provide the necesarry oxygen for the blood to circulate.
Posted by JPSO at 17:49