Understanding Fainting – The Basics

What Is Fainting?
Fainting also can be called syncope, which is a sudden, brief loss of consciousness and posture caused by lower blood flow to the brain.

Many different conditions can cause fainting, these include issues such as seizures, irregular heartbeats, low blood sugar (hypoglycemia) and, anemia (a shortage in functional oxygen-bearing cells). These conditions can also cause difficulties with how the nervous system (the human body’s system of nerves) controls blood pressure. Some types of fainting are possibly heredity based on family traits.

While fainting may register as a particular medical condition, occasionally, it may happen in an otherwise healthy person. Fainting is a specific problem for the elderly who can suffer severe injuries from falls when they faint. Most episodes are very abrupt in most situations, the individual who has fainted recovers to full consciousness within just a few minutes.

Fainting is a frequent problem, accounting for an estimated 3% of emergency room visits and 6% of hospital admissions and it can occur in otherwise healthy people. A person may exhibit faint symptoms and lightheaded (presyncope) or lose consciousness (syncope).

What Causes Fainting?
Fainting may have a variety of causes. A single episode, also known as a vasovagal attack or neurally-mediated syncope, is the most common type of fainting spell and is most prevalent in children and young adults. A vasovagal attack occurs because blood pressure drops, reducing circulation to the brain, and triggering loss of awareness. This typically occurs while standing and is frequently led by a feeling of lightheadedness, warmth, nausea, and visual “gray out.” If the syncope is extended, it can trigger a seizure.

You may suffer from small or non-serious fainting spells due to anxiety, fear, pain, intense emotional pressure, hunger, or use of alcohol or medications. Most people who endure simple fainting have no critical or underlying neurological (nerve or brain) or heart problem.

Some people have a problem with the process in which their body monitors their blood pressure, particularly when they move too fast from a lying or sitting position to a standing position. This condition is described as postural hypotension and may be severe enough to induce fainting. This type of fainting is more prevalent in the elderly, people who lately had an extended illness that kept them in bed, and people who have weak muscle tone.

The following can cause fainting, too:
Illness of the autonomic nervous system, which is the section of the nervous system that regulates involuntary vital functions, such as the heart beating, the extent to which your blood vessels contract, and breathing. Autonomic nervous system problems involve acute or subacute dysautonomia, chronic post-ganglionic autonomic insufficiency, and continued pre-ganglionic autonomic insufficiency. If you have one of these disorders, you are prone to have other symptoms, such as erectile dysfunction (incapacity to have or keep an erection), loss of bladder and bowel control, loss of the natural reflexes of your pupils, or reduced tearing, sweating, and salivation.

Other conditions can impede other parts of the nervous system that manage the blood pressure and heart rate. These include diabetes, malnutrition, alcoholism, and amyloidosis (in which smooth protein accumulates in the tissues and organs). If you take particular high blood pressure drugs, which act on impacting your blood vessels, you may be also likely to experience fainting. If you are dehydrated, which can affect the quantity of blood in your body and, therefore, your blood pressure, you may be more likely to faint.

Heart or blood vessel issues that hinder blood flow to the brain may comprise of a heart block (a problem with the electrical impulses that regulate your heart muscle), heart arrhythmia (irregular heart rhythm), difficulties with the sinus node (a specific region of your heart that helps it beat), a blood clot in the lungs, an excessively restricted aortic heart valve, or other specific problems with the structure of your heart.

There are conditions that may produce unusual patterns of stimulation to particular nerves. These involve micturition syncope (fainting during or after urination), glossopharyngeal neuralgia (fainting due to inflammation and pain in a distinct nerve to the mouth); cough syncope (fainting after intense coughing), and stretch syncope (fainting that happens when extending the neck and arms).

If you become deeply anxious or unnerved and breathe too rapidly, you may feel faint from hyperventilation (breathing in too much oxygen and exhaling too much carbon dioxide too quickly).

What are the symptoms and signs of fainting?
When a person faints, they do not know that they have passed out and fallen to the ground. Afterward the episode, they understand what has happened.

Before fainting a person may experience
  • Sweaty
  • Nauseated
  • Weak
  • Muffled hearing
  • Blurred or Faded vision
  • Dizziness or Room spin (Vertigo)
  • Tingling sensations in the body
  • Lightheaded

After a syncopal episode, the individual should recover into normal mental function. However, there may be additional signs and symptoms of fainting based on the underlying cause of fainting. For example, if the person has a heart attack, he may complain of chest pain or pressure.

What causes fainting?
  • The heart fails to pump the blood
  • The blood vessels do not have enough strength to sustain the proper blood pressure to pass the blood to the brain.
  • There is not enough fluid or blood within the blood vessels.
  • There may be a combination of causes one, two, or all three.

Vasovagal (vagal nerve) syncope
Vasovagal syncope is one of the most frequent causes of fainting. In this situation, the equilibrium between the acetylcholine and chemicals adrenaline is disturbed. Adrenaline stimulates the body, including prompting the heart to beat faster and blood vessels to contract, thereby increasing blood pressure. Acetylcholine does the opposite. When the vagus nerve is spurred, excess acetylcholine is discharged, the heart rate decreases and the blood vessels dilate, causing it more difficult for blood to overcome gravitation and be pumped to the brain. This brief decrease in blood flow to the brain causes the fainting episode.

Pain can stimulate the vagus nerve and is a prevalent reason for fainting (vasovagal syncope). Other noxious stimuli can cause a similar reaction, including situational stressors. Generally, medical and nursing students faint when observing their first procedure, autopsy, or when a person or someone else is bleeding. Some people will pass out when they hear bad news; others pass out when they experience the sight of blood or needles. In the 18th an 19th century, this was called a “swoon.”

Other conditions usually cause the heart rate to slow and develop a fainting episode momentarily. Straining with coughing, bowel movement, or urination can cause a vagal response, heightened acetylcholine levels, and decreased blood flow to the brain. These can include:

Balance Disorders
Vertigo, Motion Sickness, Labyrinthitis, and
anemia, dehydration, and Low blood pressure (postural hypotension).

Fainting during pregnancy
Fainting is associated with pregnancy, as well. Likely reasons comprise of compression of the inferior vena cava (the large vein that returns blood to the heart) by the waxing uterus and by orthostatic hypotension.

Low blood pressure (orthostatic hypotension)
Blood vessels necessitate their condition so that the body can endure the effects of gravity with changes in position. When the body position shifts from lying down to standing, the autonomic nervous system (the portion of the brain not under voluntary control), increases tone in the blood vessel walls, causing them to constrict, and at the same time boosts the heart rate so that blood can be pumped upward to the brain. As people grow older, blood vessels may grow less resilient, and orthostatic hypotension (relative low blood pressure with standing) may occur and produce syncope.

Anemia ( insufficient/low red blood cell count), whether it transpires acutely from bleeding or slowly for various reasons, can produce fainting because there aren’t sufficient red blood cells to transport oxygen to the brain.

Dehydration or absence of water in the body can likewise trigger fainting or syncope. This can be caused by extreme loss of water from vomiting, diarrhea, sweating, or by inadequate fluid intake. Some ailments like diabetes can cause dehydration by excessive loss of water in the urine.

Heart Attacks
In young people, particularly athletes, fainting, or syncope can occur because of abnormal hardening thickening of parts of the heart muscle (hypertrophic cardiomyopathy). This may interfere with blood when it attempts to leave the heart, mainly when the heart is demanded to beat harder during exercise. Sudden death in athletes may be portended by episodes of syncope.

Heart Valve Conditions
Abnormalities with the heart valves can also trigger fainting or syncope. The valves enable blood to go in an accurate direction when the heart pumps. Valve diseases may constitute abnormal narrowing (stenosis) or leakage (insufficiency or regurgitation). Either condition can cause issues with managing adequate blood flow to the body.

Heart Structural Conditions
Fundamental dilemmas with the heart can cause fainting or syncope, either due to being a problem with the ability of the heart to sufficiently pump blood or because of valve problems. When the heart muscle becomes impaired or swollen, it may not have the capacity to pump blood to meet the body’s needs. Conditions include cardiomyopathy (heart muscle weakening) or even a heart attack (myocardial infarction).

Heart Rhythm Changes (Accelerated Heartbeat and Tachycardia)
Heart rhythm variations are the most prevalent causes of passing out, fainting, or syncope. Often, fainting episodes are caused by a momentary change in normal body function.
Heart rhythm changes like tachycardia are more serious and potentially life-threatening causes of fainting.

Tachycardia (tachy = fast + cardia = heart) or a rapid heart rate is an abnormal heart rhythm that is produced in either the upper or lower chambers of the heart and can be life-threatening due to the heart beating too fast and may not be sufficient time for it to fill with blood. This then creates a reduction in the volume of blood that can be transported to the body. Tachycardias can happen at any age and may not be related to atherosclerotic heart disease.

Vertebrobasilar Artery Disease
Blood vessels to the brain are no different than any other blood vessel in the body and are at risk for growing smaller with age. While most individuals are aware of the carotid arteries that provide blood and oxygen, the reasoning and logical parts of the brain, another set of arteries serve the base of the brain. This vertebrobasilar system is also in danger of narrowing, and should there be a brief disruption in the blood flow to the reticular activating system and the midbrain, fainting or syncope may transpire. The vertebral arteries extend into the brain in the back of the neck and are wrapped in bony tunnels. If blood flow in these arteries is obstructed, the brain stem and reticular activating system may turn off, causing syncope.

Electrolyte Imbalance
Electrolyte and hormone abnormalities can also be accountable for syncope; these cases are due to their impact on blood vessels and the heart.

Other Medications and Drugs
Other medicines or prescriptions can also possibly induce fainting, including people with high blood pressure that can expand blood vessels, antidepressants that can impact heart electrical activity, and those that impact mental statuses like pain medications, alcohol, and cocaine.

Health Life Media Team