 Imagine you're in a crowded area and all of a sudden you saw someone collapsing to the ground. What would you do? Well, obviously you will run to help that person, right? And when you reach that person or when you get closer to the person who has collapsed, you notice that apart from him being unconscious on the floor, he is also not breathing and he do not have any pulse. Well, that indicates that the person got a cardiac arrest. So what should you do now? Well, to understand the next line of action, you should understand what is a cardiac arrest in the first place, right? So cardiac arrest is when the heart suddenly stops beating. Heart suddenly stops beating. Now who controls the beating of the heart? Is it the brain? Well, the brain do have some influence over the heartbeat but it is not the spot where the heartbeat generates. Our heart generates its impulse on its own with the help of nodal tissues. Now we have a whole different video on nodal tissues that talk about the awesome capability of these tissues to generate electrical impulse. So we won't talk in detail about it here. But all I wanted us to know is that these nodal tissues are like the power generator of the heart. It can generate impulse and also helps radiate the impulse to the whole cardiac muscle forming a mesh or an electrical wire kind of a system inside the heart. So we often say that the heart has its own generator and its own electrical wiring system. And cardiac arrest is the condition when this whole electrical system suddenly collapses. So when the heart do not have its own electrical supply, it fails to do its job. And what's the job of the heart? To supply blood to the whole body, right? To the brain and the rest of the body. Here I have made the vital organs. So no supply of electricity means no supply of blood both to the brain and the rest of the body. Well here the very first obvious question would be why did the heartbeat stop in the first place? I mean we just discussed that the heartbeat on its own, it is so self-sufficient. Then is it a fool that it would stop beating and would want to kill itself? Well sadly the heartbeat stops due to a number of underlying heart conditions like coronary artery disease or a heart attack. When there is a heart attack, the blood supply to the heart stops, right? So in that case if a major portion of the heart muscle dies, then it impairs the electrical activity of the heart as well. Finally causing a cardiac arrest. Or sometimes it could be the fault of the valves of the heart, the valves may act funny causing disturbance in the electrical activity of the heart. Or sometimes it could also be a hereditary condition. However, sudden cardiac arrest can happen to people who have no known heart disease at all. So it is seen that it can happen to anyone, anyone of any age group. So when it stops beating suddenly, there will obviously be no pulse rate, right? So when you check the person who collapsed, you will get no pulse. But why is the person not breathing? How did breathing stop all of a sudden? What do you think? Well as you can see the blood flow to the brain and the rest of the body stops. And brain is the main control center of our body that controls all vital activities of our body from breathing to locomotion to all the vital activities you name it. It is all controlled by the brain. And when the brain stops functioning, everything else sees us to work, even the breathing. It stops so abruptly that the person who collapsed will have no memory of him being unconscious. The brain has a temporary memory loss. And if the circulation to the brain is not restored within 2-3 minutes, then there could be irreversible changes in the brain. And if not treated immediately, death of the person is inevitable. So in such a scenario, what should you do? I mean if you think of rushing the patient to the hospital, there are high chances that you would not reach the hospital within 2-3 minutes, right? So in such a case, the first thing you need to do is to call an ambulance. Second, you should call out loud for help so that if there are any doctors or paramedic near you, they can come rushing towards the victim for help. And they will have better understanding of the situation than you do, right? And thirdly, if you do not get any help, you should start a CPR, which is cardiopulmonary resuscitation. A very fancy name again, but it simply means to regain or restore the cardiac function. As you can see in the video, CPR is just a compression of the chest in a particular way where 30 compressions are followed by 2 ventilations. Ventilation again is blowing into the mouth of the victim. Again, both of this compression and ventilation has proper procedures. You need to perform this differently in an adult and a kid or an infant, okay? With CPR, we are just trying to mimic the activity of the heart. We are manually pumping the heart so that the blood can reach the brain and all other body parts till the person receives more advanced care, till the person reaches a hospital, right? Most instances of cardiac arrest occur outside the hospital. That's why CPR is a skill that most individuals should challenge themselves to master. If a proper CPR is administered to the victim within the first few minutes of cardiac arrest, it doubles or triples the victim's chances of survival. So everyone should know this basic life support skill because it can be needed at any time. You will be ready to jump into action anytime you are around someone who collapses, right? So this was the basics about cardiac arrest.