An exhausted athlete at the end of the run, a student standing in the sun saluting the flag, or maybe a woman in a moment of sudden seeing blood …
Perhaps, you have at least experienced that feeling once in your life. You see your body lightheaded, stomach ache, sweaty palms. The scene in front of your eyes is black while your ears have a ringing sound.
Then you wake up on the floor, or on the bed and look up at a white ceiling. It takes a while for you to realize that you've just fainted. After all, what happened?
What happened in a person who fainted?
Fainting – or a medical term called unconsciousness – can happen in many situations and is influenced by many factors. But again, it is only the final consequence of a simple phenomenon: when the brain does not get enough blood.
As you know, people need to maintain a certain level of blood pressure to push blood carrying oxygen, to reach every cell and tissue in the body. All do not escape the laws of physics.
When you stand, your brain is in a position higher than your heart, so your heart needs to create enough pressure to push the blood column in the circuit against gravity and go to the brain. There will be some factors that can interrupt this process, and cause you to collapse before knowing what happened.
So what are those factors? Why do you faint?
1. Fainting due to nervous reflexes
Until now, nerve reflexes are still the most common cause of fainting. Blood pressure can be reduced by vasovagal reaction, named after the vagus nerve that runs from your brain to your heart, lungs and gastrointestinal tract.
The work of vagus nerve is to regulate the parasympathetic nervous system. It is half of the autonomic nervous system that controls the activities that take place in the body without you having to actively think about them, such as when your body is resting, saliva secretion or digestion. foods.
In the heart, the vagus nerve releases a neurotransmitter called acetylcholine. Acetylcholine binds to rhythmic cells to slow the heart rate down. Actions such as deep and slow breathing while meditating or practicing yoga are actually trying to stimulate sympathetic nerves to slow your heart to help you relax.
Although relaxation is a good thing, slowing your heart too much is not good – because sometimes it can lead to a brief moment in which you faint. Usually we need a steady heartbeat, circling a number every minute to maintain our overall blood pressure.
Sympathetic neural reflexes are still the most common cause of fainting
The other half of your autonomic nervous system is the sympathetic nervous system. The sympathetic nervous system is responsible for natural reactions when you face danger. It causes your pupils to relax, heart rate increases, lungs expand, increase adrenaline …
The sympathetic nervous system ensures that small blood vessels in your body's tissue maintain a level of contraction. This vasoconstrictive activity also contributes to maintaining your blood pressure.
The formula here is: when sympathetic activity occurs excessively, limiting the sympathetic system, the circuit does not tighten enough to the level that causes your blood to remain in the peripheral tissues, such as cornering. instead of going back to the heart to go to the brain.
The process will also make your heart rate and blood pressure drop very low, and you faint.
2. Fainting due to external psychological impact
Although physical mechanisms will explain why you fainted more appropriately. But there are still psychological causes for this phenomenon. Think of a person who fainted when he saw blood. What happened leading to excessive vasovagal reaction?
Usually, when you experience sudden stresses – such as when you're afraid of blood and seeing blood – your body will trigger a fear reaction, increase the sympathetic nervous system activity and increase your heart rate. up.
But the regulatory mechanism immediately recognizes the problem, which will compensate by increasing parasympathetic neuronal activity, to slow the heart rate back to normal levels. This is the sensitive point where the problem occurs.
If the sympathetic system over-compensates too much and reduces the heart rate too much, your blood pressure can turn around and drop too quickly, the brain will then lose oxygen and lose consciousness.
Some people fainted when they saw blood
However, even if you have fainted for any reason, most of it is just a temporary reaction. People will wake up immediately, some researchers have suggested that syncope is a self-defense reflex.
Assuming you faint and lie on the ground, blood will no longer bear gravity as they flow from your heart to your brain. The process will be easier, and you wake up. In the case of psychological fainting, such as a person who has an accident and sees that he has too much blood, fainting also causes them to lie motionless, which helps to stop bleeding and reduces the chance of getting more seizures New brand.
Even so, syncope is not completely harmless. The process by which your body moves from standing to lying is the most dangerous aspect of it. Falling falls due to fainting can cause you to hit your head or other body parts on the floor, causing injury.
In some cases, such as a voluntary blood donor, research shows that they have fainted not because of psychological factors but because of the blood loss itself.
A study in which volunteers were shown video of blood and blood transfusions. The video of the blood transfusion triggered a stronger sympathetic response than a blood transfusion video, showing that something special here has yet to be explained.
The team has also shown that, if a person believes that they can stop the test at any time, vasovagal symptoms can be minimized. This suggests that fear or lack of control may contribute to the severity of the incarceration response.
Donating blood can make people faint, both for psychological and physical reasons
3. Minimize danger
In order to minimize the dangers that may occur when you faint, you need to understand the situations in which it may occur. Besides, women need to pay more attention than men, because they have a higher rate of fainting.
There are several strategies that can help you prevent fainting:
– Immediately when you feel your body is not okay, lie down, raise your knees or legs to allow blood to flow back to your brain.
– Massaging or contracting muscles in the legs and arms, to help blood from the peripheral areas accumulate to the body center
– Always drink enough water to maintain a low blood viscosity
Finally, don't worry too much. Fainting is not a scary sign. Unless that happens often and continuously, you will need to see a doctor for examination and treatment.