Fainting (syncope) is the partial or complete loss of consciousness with interruption of awareness of oneself and ones surroundings. When the loss of consciousness is temporary and there is spontaneous recovery, it is referred to as syncope or, in nonmedical terms, fainting. Syncope accounts for one in every 30 visits to an emergency room. It is pronounced sin-ko-pea.
Syncope is due to a temporary reduction in blood flow and therefore a shortage of oxygen to the brain. This leads to lightheadedness or a "black out" episode, a loss of consciousness. Temporary impairment of the blood supply to the brain can be caused by heart conditions and by conditions that do not directly involve the heart.
Other causes of fainting
Non-heart Causes: Syncope is most commonly caused by conditions that do not directly involve the heart. These conditions include the following:
- Postural (orthostatic) hypotension: drop in blood pressure due to changing body position to a more vertical position after lying or sitting
- Diseases of the nerves to the legs in older people (especially with diabetes or Parkinson's disease) when poor tone of the nerves of the legs draws blood into the legs from the brain
- High altitude
- Fainting after certain situations (situational syncope) such as
- blood drawing,
- urinating (micturition syncope),
- defecating (defecation syncope),
- swallowing (swallowing syncope),
- coughing (cough syncope) that trigger a reflex of the involuntary nervous system (the vasovagal reaction) that slows the heart and dilates blood vessels in the legs and cause one to feel nausea, sweating, or weakness just before fainting.
Heart Causes: Heart conditions that can cause syncope or fainting due to temporary loss of consciousness include:
- Abnormal heart rhythms (heart beating too fast or too slow)
- Abnormalities of the heart valves (pulmonic valve stenosis)
- Widespread disease of the heart muscle (cardiomyopathy)
Medications can cause fainting by altering blood pressure or by affecting the heart.Next Article
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Causes of Fainting
Anaphylaxis is a serious allergic reaction that affects a number of different areas of the body at one time, and can be fatal. Causes of anaphylaxis can be food allergy, latex allergy, allergy to insect or but stings/bites, asthma, or other materials or conditions. Symptoms include flushing, itching, hives, anxiety, rapid or irregular pulse. Severe symptoms may be throat and tongue swelling, swallowing, and difficulty breathing. Some disorders appear similar to anaphylaxis such as fainting, panic attacks, blood clots in the lungs, heart attacks, and septic shock. If you think that you may be having an anaphylactic reaction, seek emergency care or call 911 immediately.
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased. There are several types of anemia such as iron deficiency anemia (the most common type), sickle cell anemia, vitamin B12 anemia, pernicious anemia, and aplastic anemia. Symptoms of anemia may include fatigue, malaise, hair loss, palpitations, menstruation, and medications. Treatment for anemia includes treating the underlying cause for the condition. Iron supplements, vitamin B12 injections, and certain medications may also be necessary.
Aortic dissection is a small tear in the large blood vessel that leads from the heart and supplies blood to the body. There are two types of aortic dissection, type 1 and type 2. Signs and symptoms of aortic dissection include a tearing or ripping pain, nausea, sweating, weakness, shortness of breath, sweating, or fainting. Treatment depends on the type of aortic dissection, and the severity of the tear in the aorta.
Aortic Valve Stenosis (Symptoms, Causes, Surgery)
Aortic valve stenosis is an abnormal narrowing of the aortic valve of the heart. The causes of aortic stenosis are wear and tear of the valve in the elderly, congenital, or scarring or scarring of the aortic valve from rheumatic fever. Symptoms include angina, fainting, and shortness of breath. Treatment is dependant upon the severity of the condition.
Atrial Fibrillation (AFib) Treatment Drugs
Atrial fibrillation (AFib) is a heart rhythm disorder that causes irregular and often rapid heartbeat. The medications to treat AFib include beta-blockers, blood thinners, and heart rhythm drugs. Atrial fibrillation drugs can cause serious side effects like seizures, vision changes, shortness of breath, fainting, other abnormal heart rhythms, excessive bleeding while coughing or vomiting, blood in the stool, and bleeding into the brain.
Atrial Fibrillation Symptoms (AFib Warning Signs)
Atrial fibrillation or AFib is a type of hear rhythm abnormality. Early warning signs and symptoms of atrial fibrillation include chest pain, palpitations, shortness of breath, and lightheadedness. Treatment for atrial fibrillation includes medical procedures, surgery, and medication.
Atrial Flutter vs. Atrial Fibrillation (What Are the Differences?)
Atrial flutter and atrial fibrillation (AFib) are two types of a heart problem called atrial tachycardia. Both of these conditions involve the heart's electrical activity, but they are not the same disease. Both diseases are serious and need medical treatment. Common symptoms of these diseases are similar and include: Fatigue Blurry vision Lightheadedness Palpitations Feeling like you may faint Serious symptoms of both conditions are similar and include: Fainting Sweating Severe shortness of breath Chest pain Atrial flutter and AFib are heart conditions that require medical diagnosis (ECG) and treatment by a doctor or other medical health-care professional.
Dilated Cardiomyopathy is a condition where the heart's ability to pump blood is decreased because the heart's main pumping chamber is enlarged and weakened. Symptoms of dilated cardiomyopathy include chest pain, heart failure, swelling of the lower extremities, fatigue, weight gain, fainting, palpitations, dizziness and blood clots.
Hypertrophic cardiomyopathy (HCM) affects many people today. Many people with HCM have no symptoms or only minor symptoms, and live a normal life. Other people develop symptoms, which progress and worsen as heart function worsens.
Restrictive cardiomyopathy, the rarest form of cardiomyopathy, is a condition in which the walls of the lower chambers of the heart (the ventricles) are abnormally rigid and lack the flexibility to expand as the ventricles fill with blood. The pumping or systolic function of the ventricle may be normal but the diastolic function (the ability of the heart to fill with blood) is abnormal. Therefore, it is harder for the ventricles to fill with blood, and with time, the heart loses the ability to pump blood properly, leading to heart failure.
Chagas Disease (American Trypanosomiasis or Kissing Bug Disease)
Chagas disease is an infection caused by the T. cruzi parasite. Symptoms of Chagas disease include rash, swollen lymph nodes, fever, fatigue, nausea, vomiting, and the Romaña sign. An ELISA test is used to diagnose Chagas disease. Treatment depends upon the phase of the disease and the patient's age.
Chest pain is a common complaint by a patient in the ER. Causes of chest pain include broken or bruised ribs, pleurisy, pneumothorax, shingles, pneumonia, pulmonary embolism, angina, heart attack, costochondritis, pericarditis, aorta or aortic dissection, and reflux esophagitis. Diagnosis and treatment of chest pain depends upon the cause and clinical presentation of the patient's chest pain.
Dehydration is the excessive loss of body water. There are a number of causes of dehydration including heat exposure, prolonged vigorous exercise, and some diseases of the gastrointestinal tract. Symptoms of dehydration include headache, lightheadedness, constipation, and bad breath. Treatment for dehydration is to replace lost fluids and electrolytes.
Diabetes (Type 1 and Type 2)
Diabetes is a chronic condition characterized by high levels of sugar (glucose) in the blood. The two types of diabetes are referred to as type 1 (insulin dependent) and type 2 (non-insulin dependent). Symptoms of diabetes include increased urine output, thirst, hunger, and fatigue. Treatment of diabetes depends on the type.
Early Pregnancy Symptoms and Signs
Pregnancy symptoms can vary from woman to woman, and not all women experience the same symptoms. When women do experience pregnancy symptoms they may include symptoms include missed menstrual period, mood changes, headaches, lower back pain, fatigue, nausea, breast tenderness, and heartburn. Signs and symptoms in late pregnancy include leg swelling and shortness of breath. Options for relief of pregnancy symptoms include exercise, diet, and other lifestyle changes.
Heart Attack Treatment
A heart attack involves damage or death of part of the heart muscle due to a blood clot. The aim of heart attack treatment is to prevent or stop this damage to the heart muscle. Heart attack treatments included medications, procedures, and surgeries to protect the heart muscle against injury.
Heart disease (coronary artery disease) occurs when plaque builds up in the coronary arteries, the vessels that supply blood to the heart. Heart disease can lead to heart attack. Risk factors for heart disease include: Smoking High blood pressure High cholesterol Diabetes Family history Obesity Angina, shortness of breath, and sweating are just a few symptoms that may indicate a heart attack. Treatment of heart disease involves control of heart disease risk factors through lifestyle changes, medications, and/or stenting or bypass surgery. Heart disease can be prevented by controlling heart disease risk factors.
Insect Sting Allergies
The majority of stinging insects in the United States are from bees, yellow jackets, hornets, wasps, and fire ants. Severity of reactions to stings varies greatly. Avoidance and prompt treatment are essential. In selected cases, allergy injection therapy is highly effective.
Low Blood Pressure (Hypotension)
Low blood pressure, also referred to as hypotension, is blood pressure that is so low that it causes symptoms or signs due to the low flow of blood through the arteries and veins. Some of the symptoms of low blood pressure include light-headedness, dizziness, and fainting if not enough blood is getting to the brain. Diseases and medications can also cause low blood pressure. When the flow of blood is too low to deliver enough oxygen and nutrients to vital organs such as the brain, heart, and kidneys; the organs do not function normally and may be permanently damaged.
Migraine headache is a type of headache associated with a sensitivity to light, smells, or sounds, eye pain, severe pounding on one side of the head, and sometimes nausea and vomiting. The exact cause of migraine headaches is not known. Triggers for migraine headaches include certain foods, stress, hormonal changes, strong stimuli (loud noises), and oversleeping. Treatment guidelines for migraines include medicine, pain management, diet changes, avoiding foods that trigger migraines, staying hydrated, getting adequate sleep, and exercising regularly. Prevention of migraine triggers include getting regular exercise, drinking water daily, reducing stress, and avoiding trigger foods.
Palpitations (Causes and Symptoms)
Palpitations are uncomfortable sensations of the heart beating hard, rapidly, or irregularly. Some types of palpitations are benign, while others are more serious. Palpitations are diagnosed by taking the patient history and by performing an EKG or heart monitoring along with blood tests. An electrophysiology study may also be performed. Treatment of palpitations may include lifestyle changes, medication, ablation, or implantation of a pacemaker. The prognosis if palpitations depends on the underlying cause.
Parkinson's disease is a slowly progressive neurological disease characterized by a fixed inexpressive face, a tremor at rest, slowing of voluntary movements, a gait with short accelerating steps, peculiar posture and muscle weakness, caused by degeneration of an area of the brain called the basal ganglia, and by low production of the neurotransmitter dopamine. Most patients are over 50, but at least 10 percent are under 40.
POTS (POT Syndrome, Postural Orthostatic Tachycardia Syndrome)
POT syndrome (POTS, postrual orthostatic tachycardia syndrome) is a nervous system disorder that causes lightheadedness and fainting when a person stands up. Treatment may include increasing blood volume and regulating circulatory problems that are responsible for the disorder.
Pulmonary hypertension is elevated pressure in the pulmonary arteries that carry blood from the lungs to the heart. The most common symptoms are fatigue and difficulty breathing. If the condition goes undiagnosed, more severe symptoms may occur. As pulmonary hypertension worsens, some people with the condition have difficulty performing any activities that require physical exertion. While there is no cure for pulmonary hypertension, it can be managed and treated with medications and supplemental oxygen to increase blood oxygen levels.
Medical shock is a life-threatening medical condition. There are several types of medical shock, including: septic shock, anaphylactic shock, cardiogenic shock, hypovolemic shock, and neurogenic shock. Causes of shock include: heart attack, heart failure, heavy bleeding (internal and external), infection, anaphylaxis, spinal cord injury, severe burns, chronic vomiting or diarrhea. Low blood pressure is the key sign of sock. Treatment is dependant upon the type of shock.
A stroke is an interruption of the blood supply to part of the brain caused by either a blood clot (ischemic) or bleeding (hemorrhagic). Symptoms of a stroke may include: weakness, numbness, double vision or vision loss, confusion, vertigo, difficulty speaking or understanding speech. A physical exam, imaging tests, neurological exam, and blood tests may be used to diagnose a stroke. Treatment may include administration of clot-busting drugs, supportive care, and in some instances, neurosurgery. The risk of stroke can be reduced by controlling high blood pressure, high cholesterol, diabetes, and stopping smoking.
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