Why do you colapse immediatly after your heart has stopped beating because of a heart attack and not a few minutes later after your body has run out of oxygen?
In: 55
You need blood pressure for blood to move through your organs in capillaries.
As soon as your heart stop beating, your arterial blood pressure drops to the same level as vein blood pressure and all the blood in your arteries and veins become useless to you. You don’t have access to its oxygen nor the oxygen in your lungs.
The oxygen in your capillaries is used fast by the brain and then you’re unconscious.
You need blood pressure for blood to move through your organs in capillaries.
As soon as your heart stop beating, your arterial blood pressure drops to the same level as vein blood pressure and all the blood in your arteries and veins become useless to you. You don’t have access to its oxygen nor the oxygen in your lungs.
The oxygen in your capillaries is used fast by the brain and then you’re unconscious.
As soon as the heart stops beating (well between zero and a couple of seconds), your blood pressure will drop significantly. Your brain needs all the oxygen it can, and being at the top of your body, it is the hardest place to reach if blood pressure is low. So your body has a built-in defence mechanism, when your blood pressure drops too much, it makes you lose consciousness so you fall on the floor and put the head level to the heart to maximize oxygen that can reach the brain with low pressure. It is just that in that case you will never regain consciousness because blood pressure and oxygen level will increase.
Tldr: heart stops beating, blood pressure drops immediately, brains goes “oh shit, not enough pressure to reach, must force this body to drop down on the floor”, you lose consciousness
As soon as the heart stops beating (well between zero and a couple of seconds), your blood pressure will drop significantly. Your brain needs all the oxygen it can, and being at the top of your body, it is the hardest place to reach if blood pressure is low. So your body has a built-in defence mechanism, when your blood pressure drops too much, it makes you lose consciousness so you fall on the floor and put the head level to the heart to maximize oxygen that can reach the brain with low pressure. It is just that in that case you will never regain consciousness because blood pressure and oxygen level will increase.
Tldr: heart stops beating, blood pressure drops immediately, brains goes “oh shit, not enough pressure to reach, must force this body to drop down on the floor”, you lose consciousness
I feel like it’s the same reason that some people faint when they get their blood drawn vs. don’t faint when they hold their breath. I think our brains need a lot of blood and so losing a significant amount (which happens quickly if your heart isn’t beating) causes you to lose consciousness (maybe as a way to preserve energy?)
I feel like it’s the same reason that some people faint when they get their blood drawn vs. don’t faint when they hold their breath. I think our brains need a lot of blood and so losing a significant amount (which happens quickly if your heart isn’t beating) causes you to lose consciousness (maybe as a way to preserve energy?)
Your brain needs a lot of energy to run, but it’s also the only organ that isn’t capable of producing its own energy. It is entirely dependent on oxygen and glucose being constantly fed to it.
The heart pumps the juice to the squash. If the pump suddenly stops working, it doesn’t matter if there’s good stuff in the juice if it can’t go anywhere.
This is different from a respiratory / airway issue where there’s plenty of juice going to the squash, it’s just not good juice.
Your brain needs a lot of energy to run, but it’s also the only organ that isn’t capable of producing its own energy. It is entirely dependent on oxygen and glucose being constantly fed to it.
The heart pumps the juice to the squash. If the pump suddenly stops working, it doesn’t matter if there’s good stuff in the juice if it can’t go anywhere.
This is different from a respiratory / airway issue where there’s plenty of juice going to the squash, it’s just not good juice.
Minor quibble you instantly collapse on cardiac arrest (heart stop beating) not necessarily on heart attack (oxygen supply to part of heart cut off, usually a blocked coronary artery). Someone with a heart attack can be walking and taking, cardiac arrest very much not. And of course a heart attack can lead to cardiac arrest.
Have heart disease myself so very aware of this distinction!
Minor quibble you instantly collapse on cardiac arrest (heart stop beating) not necessarily on heart attack (oxygen supply to part of heart cut off, usually a blocked coronary artery). Someone with a heart attack can be walking and taking, cardiac arrest very much not. And of course a heart attack can lead to cardiac arrest.
Have heart disease myself so very aware of this distinction!
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