Do you feel a blackout when you suddenly stand up? Don't take it lightly!

Expert of this article: Yan Kaixin, Master of Cardiology, PLA General Hospital

Reviewer of this article: Chen Haixu, Deputy Director and Master Supervisor of the Second Medical Center of PLA General Hospital

Have you ever had this experience when you suddenly stand up?

Feeling dizzy and dizzy

Blackness in front of eyes

The world is spinning

…

At this time

I can only find a wall to lean on for a while before I can slowly recover the scene in front of me.

Many people think that this is due to their own anemia or just temporary fatigue.

Can self-recover

But

These symptoms may also indicate certain diseases

Everyone must be vigilant!

Let’s talk about it today

Why do you suddenly see black after standing up? Blackout, also known as transient blackout, refers to sudden blackout in front of your eyes and unclear vision, which may be accompanied by dizziness, tinnitus and other symptoms, but the symptoms will disappear on their own after resting for tens of seconds. The main reasons for this problem are as follows:

(1) Orthostatic hypotension

Also known as "postural hypotension", it refers to the phenomenon of dizziness and blacking out when suddenly standing up from lying down or squatting.

When a person suddenly stands up from a squatting position, the blood in the chest, abdomen and head will flow rapidly to the waist and legs due to gravity, causing ischemia in the upper body, especially the head, resulting in a temporary lack of blood supply to the brain, resulting in temporary cerebral ischemia.

Because the brain tissue is extremely sensitive to blood oxygen supply disorders, when the blood and oxygen supply to the brain tissue stops for 3 seconds, dizziness will occur, and fainting may occur within 10-20 seconds.

At the same time, when you stand up suddenly, the blood supply to the retina of the eye is reduced, and the optic nerve cells are stimulated, causing temporary hallucinations, like seeing stars in front of your eyes.

(2) Hypoglycemia

Some diabetic patients do not eat on time, or healthy people are in a state of hunger. Once they are hungry, they will suffer from hypoglycemia, and symptoms such as dizziness, black spots in front of the eyes, and palpitations will appear.

This is because the energy metabolism of the brain tissue relies on the glucose in the blood. When there is insufficient glucose in the blood, it will cause insufficient energy supply to the brain tissue, resulting in symptoms of dizziness and blackouts.

(3) Cardiovascular disease

People who already suffer from cardiovascular diseases, such as cardiac hypotension, arrhythmia, angina pectoris, myocardial infarction, etc., will interfere with the heart's blood output and affect the blood supply to the whole body. As a result, some people may experience sudden fainting or blacking out.

(4) Carotid artery stenosis

If plaque forms in the carotid artery, it will cause narrowing inside the artery, leading to insufficient blood supply to the head and symptoms such as black vision.

(5) Others

Vasovagal syncope, mood changes, painful stimulation, hot and stuffy environment, etc. may also cause attacks;

Carotid sinus syncope can be induced by sudden neck turning or tight collar, or by massaging the carotid sinus area. Sometimes it may occur spontaneously.

Situational syncope, also known as physiological reflex syncope, can manifest as urination syncope, defecation syncope, coughing syncope, diving syncope and swallowing syncope.

Which groups of people need special attention? First of all, when healthy adults suddenly stand up from a squatting position and experience transient blackouts, it is mostly due to orthostatic hypotension. At this time, they should squat down in time to increase the amount of blood returning to the heart, and then slowly stand up to carry out daily activities after the dizziness and blurred vision symptoms improve.

For middle-aged and elderly people, if symptoms of transient blackouts occur and are severe, in addition to excluding physiological factors (fatigue, hunger, mood changes, etc.), they should seek medical attention in time to check whether there are any cardiovascular and cerebrovascular system diseases.

For people who already have underlying diseases, they should closely observe whether it is related to their own diseases and whether the diseases have a tendency to develop further, and consult a doctor for help in a timely manner.

How to save yourself when you feel black in front of your eyes?

(1) When squatting, do not squat for too long. Stand up every 2 minutes to keep blood circulation smooth.

(2) Do not stand up suddenly. You can bend down for a few seconds before standing up, or stand up slowly.

(3) If you suddenly feel dizzy when standing up, stay calm, continue squatting or sitting down, lower your center of gravity, increase the amount of blood returning to your heart, and stand up slowly when your symptoms improve to avoid falling;

(4) Seek help from people around you in a timely manner;

(5) If the symptoms occur frequently or take a long time to resolve, you should seek medical attention as soon as possible to get a clear diagnosis;

(6) In daily life, you should eat a healthy diet, get enough sleep, avoid overwork, and increase exercise appropriately.