Syncope – Loss of Consciousness (Fainting)

Fainting is a sudden, brief loss of consciousness that is usually followed by a fall. It occurs due to a sudden drop in blood flow to the brain and can last from a few seconds to several minutes, after which the person regains consciousness. After fainting, a person may experience weakness, typically have cold extremities, a weaker pulse, and shallow breathing.

Causes of fainting can include a sudden drop in blood pressure or heart rate, experiencing stress, or an underlying medical condition. Another term for fainting is syncope. In most cases, fainting is not a cause for concern and does not require medical examination or treatment. However, if the cause of fainting is a cardiac or neurological condition, treatment will be necessary. Most people can prevent fainting by receiving an accurate diagnosis of their condition and following appropriate treatment methods.

The symptoms that can indicate an impending fainting (syncope) episode include:

• Cold sweat
• Dizziness
• Swaying
• Changes in vision (temporary blackout, flickering)
• Nausea
• Stress or anxiety
• Weakness

In addition, a person can:

• Fall
• Experience a headache
• Having ringing in the ears (tinnitus)
• Lose control of their muscles

Fainting can be preceded by a brief feeling of weakness or dizziness, a sense of impending loss of consciousness. However, symptoms can also include dimming or flashing lights in front of the eyes, as well as lightheadedness (a sensation of loss of ground beneath the feet) that can lead to a fall and fainting. A more severe form of fainting with pronounced symptoms lasting several minutes may indicate a serious condition

There are many potential causes of fainting. Many people may have heart or nervous system conditions that they are unaware of, which can contribute to fainting episodes. Additionally, fainting can be caused by a drop in blood pressure upon changing positions (e.g., getting up suddenly).

Fainting caused by heart conditions: Fainting can occur if there is a heart or blood vessel disorder that disrupts blood flow to the heart. These may include:

• Abnormal heart rhythm (arrhythmia) – bradycardia and tachycardia
• Disruption of blood flow to the heart due to heart structure (hypertrophic cardiomyopathy).
• Blockage of the heart’s blood vessels (myocardial ischemia).
• Heart valve diseases
• Aortic stenosis (narrowing)
• Blood clot
• Heart failure

Fainting associated with neurological disorders: Fainting can occur with stroke or transient ischemic attacks (TIA), epileptic seizures, and, less commonly, migraines.

Postural hypotension or orthostatic hypotension occurs when blood pressure suddenly drops due to a rapid change in position, such as getting up quickly from a lying position. Certain medications and dehydration can lead to this condition. People with this type of fainting (syncope) typically have changes in blood pressure that cause it to drop by at least 20 millimeters (systolic/upper number) and at least 10 millimeters of mercury (diastolic/lower number) when standing.

Postural Orthostatic Tachycardia Syndrome (POTS) is characterized by a rapid heartbeat (tachycardia) that occurs when a person stands up from a sitting or lying position, while most of the blood remains in the legs. The pulse rate can increase by 30 beats per minute or more. The increase usually occurs within 10 minutes after standing up.

Certain medications for high blood pressure such as diuretics, calcium channel blockers, and angiotensin-converting enzyme (ACE) inhibitors can cause fainting. Fainting can also be caused by antidepressants, antihistamines for allergies, opioids, and analgesics.

Fainting due to diabetes: It is caused by a sudden drop in blood sugar in individuals with diabetes.

Situation-specific syncope, a type of vasovagal syncope occurs only in certain situations that affect the nervous system and lead to syncope.

Specific activities that can cause fainting include:

• Dehydration
• Overheating and excessive exertion
• Skipping meals, hunger
• Hyperventilation (rapid breathing)
• Use of alcohol, marijuana, or illegal drugs
• Fainting of unknown origin: The cause of syncope is unknown in approximately 33% of people.

A doctor will conduct a physical examination and review the patient’s medical history. They will ask detailed questions about the symptoms and episodes of fainting, whether there are any symptoms before fainting, and when and where consciousness returns. The doctor will measure the patient’s pulse and blood pressure in different positions.

Blood analysis to check for anemia or metabolic changes. Electrocardiogram (ECG): A test that records the electrical activity of the heart.

Exercise stress test, which monitors changes on the ECG. Stress echocardiogram is a method used to detect coronary artery disease by directly assessing the heart’s function.

The Holter monitor records the heart’s activity, including changes in pulse and rhythm during daily activities.

A test to check whether there are structural changes in the heart.

A series of different tests that measure blood pressure, blood flow, heart rate, skin temperature, and sweating in response to specific stimuli. These measurements can help the doctor determine if the autonomic nervous system is functioning properly or if there is nerve damage.

Treatment options are determined based on the underlying cause of fainting and the results of diagnostic testing.

Syncope treatment options include (especially for individuals over 65 who faint upon sudden standing up):

• Medication adjustments or changes if the patient is already taking medication.
• Wearing compression socks to improve blood circulation.
• Making changes to the diet: smaller, more frequent meals, higher salt intake (only if the doctor recommends), plenty of fluids, an increase in potassium in the diet and avoidance of caffeine and alcohol.
• Leg exercises.

If fainting occurs due to a diagnosed heart problem, your doctor may recommend one of the following treatment options:

• Medications
• Pacemaker
• Implantable cardioverter defibrillator (ICD)
• Catheter ablation
• Heart valve replacement

You’ll probably be able to avoid unconsciousness if:

• Sit or lie down and elevate your legs.
• Sit down, lean forward, and place your head between your knees.
• Clasp your fists. Keep your hands tight or tense.
• Cross your legs or squeeze your thighs together.

If someone loses consciousness:

• Ensure that the person’s airways are clear and check if they are breathing and have a pulse.
• Initiate CPR if the person is not breathing or you cannot detect a pulse.
• Call an ambulance.

When someone faints and regains consciousness:

• Advise the person to sit or lie down for 10 to 15 minutes (sometimes longer, until the symptoms pass).
• Check for any injuries that may require medical attention (head injury or cuts).
• Offer ice or cold water.

Fainting can recur in individuals with untreated underlying causes of fainting.

People who faint due to low blood pressure upon standing (orthostatic hypotension) may be at risk of injury from falls.

Type 2 diabetes can also lead to fainting due to low blood sugar (hypoglycemia), which poses a risk of stroke.

Fainting caused by heart conditions can have fatal outcomes. If left untreated, individuals with cardiac syncope are at least twice as likely to experience a traffic accident compared to others.

Many people can sense when fainting is about to occur. They may feel dizziness, nausea, and palpitations (irregular heartbeats that feel like “fluttering” in the chest). Reducing the risk of fainting can be easy if dehydration is the cause. However, if the cause is a heart condition, medication therapy or an implantable device to treat abnormal heart rhythms may be necessary.

• Be particularly cautious when getting up. If you occasionally faint due to getting up too quickly, try to take your time when standing up.
• Elevate the head of your bed with pillows while sleeping.
• Avoid triggers that can provoke a fainting episode (such as prolonged standing, heat, or emotional stress).
• Maintain a healthy diet and make dietary changes if advised and approved by your doctor (increase salt intake, potassium, etc.).
• Stay hydrated regularly (drink 8 glasses of water per day).
• Exercise regularly but consult with your doctor about the type of exercises that are suitable for you.
• Avoid engaging in physical activity in high temperatures or take breaks and hydrate regularly.
• Take your prescribed medication regularly and consult with your doctor if you feel that the medication is not suiting you.

With proper diagnosis and treatment, you can avoid or control fainting episodes. If you have experienced one episode of fainting, research shows that there is approximately a 30% chance of experiencing it again. The risk of recurrence and how it will impact your health depends on several factors, including the underlying cause, your age, gender, and other health conditions you may have.

If you faint once and are otherwise in good health, you may not need to see a doctor. However, it is important to consult a doctor if:

• You have an injury from falling during the fainting episode.
• You faint while exercising.
• Fainting episodes occur frequently.
• It takes several minutes for you to regain consciousness.
• Report any loss of consciousness to your doctor if you are pregnant, have diabetes or a family history of heart disease or sudden death.

Seek immediate medical attention if you experience the following symptoms along with fainting:

• Chest pain
• Confusion or difficulty speaking
• Irregular heartbeat
• Loss of bladder or bowel control
• Shortness of breath.

Fainting or syncope usually occurs due to a drop in blood pressure, which reduces blood flow and oxygen to the brain. Although most syncope episodes are not dangerous, they can be life-threatening if you have underlying heart or neurological conditions. Consult a doctor if you experience recurrent episodes of fainting or have any other accompanying symptoms.

Identifying the cause can help you take measures to prevent future fainting episodes