Summer vacation is a period of high incidence of drowning accidents among primary and secondary school students. In the event of a drowning incident, if the drowning person is brought ashore, the rescuer usually squeezes the chest to give first aid.
Why, then, is it necessary to squeeze the chest hard in the first place for a drowning person?Squeezing the chest, in technical terms, is cardiac compressions, which is an important step in CPR. Because oxygen is needed to survive, and oxygen passes through the lungs into the bloodstream, the heart transports oxygen-rich blood to every cell throughout the body. The organ that uses the most oxygen throughout the body is the brain, and without oxygen, brain function can only last for a few minutes. After drowning, the most vulnerable to damage are brain cells: after 10 seconds of cerebral hypoxia, a person can lose consciousness;Hypoxia for 4 to 6 minutes, brain neurons will undergo irreversible pathological changes;Hypoxia for 6 and 9 minutes mortality reaches 65;After 12 minutes, the survival rate is almost zero.
When a person is drowning, the heart stops beating and the brain is starved of oxygen, and by squeezing the chest, it is able to provide vital blood flow to the heart and brain, providing oxygen and energy to the brain and heart. The timing and degree of hypoxia directly affect the success rate of cardiopulmonary resuscitation and the effectiveness of cerebral resuscitation. Therefore, early on-site rescue of drowning must be fast, effective, and every second counts. The first is to squeeze the chest of the drowning person vigorously, and the rescuer uses the palm of one hand to stick to the chest wall of the middle and lower sternum of the drowning person 1 3 places, so that the sternum sinks 5 cm, and the hand is relaxed after pressing down, so that the chest wall of the drowning person returns to its original state, and then presses down again. Chest compressions are performed continuously at a rate of at least 100 times per minute. Don't forget to call "120" for emergency treatment**.
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