What is Fainting? Symptoms, Causes and Treatment

2022-04-29 00:00:00

Fainting is a temporary loss of consciousness that occurs when the brain doesn't receive proper oxygen supply. It is a sudden episode that lasts for fragments of seconds or a minute. Although the loss of consciousness is sudden, recovery of consciousness also takes place in no time. The medical term for this situation is ‘syncope’whereas generally the word ‘blackout’ can be used for the same. Normally, people confuse fainting with seizures due its sudden onset but both are different as seizures show many other symptoms along with loss of consciousness like- upward rolling of eyes, jerky movements of body parts in contrast to which fainting doesn't show any of these symptoms. Fainting is common among teenagers and affects girls more than boys. People of all ages can faint but older people can have serious underlying causesbehind it.

Types of Fainting

There are several types of syncope. Three common types are:

Vasovagal syncope 

Vasovagal syncope affects the vagus nerve. It can be caused by emotional trauma, stress, seeing blood or standing for a long period of time.

Carotid sinus syncope 

This type occurs when the carotid arteries in the neck are constricted, usually after turning the head sideways or wearing a collar that is too tight.

Situational syncope 

This occurs due to shortness of breath due to heavy coughing, urinating, defecating or having digestive problems.

Cardiac syncope

 This type of syncope occurs due to a heart problem. Many heart conditions can affect how much oxygen-rich blood is pumped to the brain.

Symptoms and Signs of Fainting

Before fainting, a person may exhibit or feel all or some of these signs and symptoms-

• Confusion
• Dizziness
• Weakness
• Shortness of breath
• Headache
• Sweating
• Sudden trouble in hearing
• Blurred vision
• Nausea
• Feeling hot
• Shaking or Trembling

In case of fainting caused by stimulation of the vagus nerve, a person may experience the spasm or the urge to have a bowel movement just before the person passes out.

Causes of Fainting

Here are some of the common causes of fainting-

Neurocardiogenic syncope

 Neurocardiogenic syncope develops due to short-term dysfunction of the autonomic nervous system (ANS). Some people call it neuron mediated syncope (NMS).

Possible triggers for neurocardiogenic syncope are-

• Uncomfortable or shocking images, such as seeing blood.
• Sudden contact with unpleasant sights or experience.
• Sudden emotional upheaval, such as after receiving tragic news.
• Embarrassment.
• Not moving for a long time.
• Strenuous physical activities like heavy weight lifting.

Orthostatic Hypotension

 It refers to fainting after getting up too quickly from a sitting or horizontal position.

Gravity pulls blood into the legs and lowers blood pressure elsewhere in the body. The nervous system normally responds by increasing the heart rate and constricting blood vessels. It stabilizes blood pressure.

However, if something interferes with this stabilization process, it can result in poor blood and oxygen supply to the brain, leading to fainting.

Possible triggers are-

• Dehydration-If the fluid level in the body drops, the blood pressure also drops, makingit difficult to stabilize your blood pressure. As a result, less blood and oxygen reaches the brain.
• Uncontrolled diabetes-A person with diabetes may need to urinate frequently, leading to dehydration.
• Some medicines-Taking diuretics, beta-blockers, and medicines to lower blood pressure can cause orthostatic hypotension in some people.
• Alcohol-Some people pass out after drinking too much alcohol for a short time.
• Certain Neurological Disorders-Neurological disorders can affect the nervous system. This can cause orthostatic hypotension.
• Carotid Sinus Syndrome-The carotid artery is the main artery that supplies blood to the brain. When pressure is applied to the pressure sensors or the carotid sinus in the carotid artery, it can cause fainting.

Cardiac syncope-

Major heart problems can reduce the supply of blood and oxygen to the brain. Possible heart problems are-

• Cardiac arrhythmias or abnormal heart rhythm.
• Stenosis or obstruction of the heart valves.
• Hypertension or high blood pressure.
• Heart attack, due to lack of blood and oxygen in the heart.

This usually requires immediate medical attention and close monitoring.

Can Fainting be Prevented?

Ways to prevent fainting-

• If you feel like fainting, lie down and place your feet slightly higher than your head. Be careful when moving, especially when moving from a lying or standing position. Change positions very slowly.
• If you are pregnant, avoid lying on your abdomen, especially in the last months of pregnancy, as the pressure of the enlarged uterus (womb) on the main blood vessels can cause fainting.
• Eating healthy and not skipping meals can help. Drink plenty of clean fluid.
• If you faint, you should avoid driving or using machinery until you have discussed your problem with your doctor.
• If you are suddenly scared and feel like you might pass out, take a deep breath and slowly count to 10 to calm yourself down.
• Avoid alcohol

When to seek a doctor?

Fainting can be a sign of medical conditions such as heart or brain disease. Therefore, it is always a good idea to consult your doctor, especially if you have not fainted beforeand also if

• You have fainted and don't know the cause.
• You have recently fainted more than once.