Sudden Fainting

Fainting and thus losing control of oneself for a moment is disturbing. Yet behind the unconsciousness are usually quite harmless causes, such as low blood pressure. Often, symptoms such as dizziness, sweating or nausea appear shortly before the person faints. In the case of other causes, such as cardiac arrhythmia, fainting does not announce itself in advance, but occurs quite suddenly. We reveal what causes can be behind a fainting and how you should behave in an emergency.

Causes of fainting

A short fainting spell – usually lasting only a few seconds – is called syncope. If unconsciousness lasts longer, it is called a coma. Syncope is caused by a temporary circulatory disturbance in the brain. The causes of this circulatory disturbance are varied and cannot always be determined with certainty in retrospect. In addition to harmless triggers such as low blood pressure, serious diseases are also possible causes. In general, the causes of fainting can be divided into four groups:

  • Orthostatic syncope
  • Vasovagal syncope
  • Cardiac syncope
  • Cerebrovascular syncope

Orthostatic and vasovagal syncope

Fainting is often caused by a collapse of the circulation – a circulatory collapse. This is favored by various factors, such as low blood pressure. But a lack of fluids and varicose veins are also considered risk factors. Typically, fainting in such a case occurs when changing too quickly from lying or sitting to standing. Blood pools in the leg vessels and the brain is no longer supplied with sufficient oxygen. Vasovagal syncope is caused by the body’s reflex response being too strong. When certain stimuli occur, the vagus nerve automatically causes the blood vessels to widen and the heart rate to decrease. As a result, the blood sinks and the brain is no longer supplied with sufficient blood – fainting occurs. Triggers can include mental stress, cold, pain, fear, bad news or a joyful event.

Cardiac and cerebrovascular syncope.

Cardiac syncope is caused by a disturbance in heart function and is therefore particularly dangerous. Most often, it is cardiac arrhythmias that affect the circulation. However, structural changes in the heart tissue can also trigger fainting. The dangerous thing is that in cardiac syncope, the heart stops without warning. As a result, fainting occurs suddenly and without prior symptoms. If the heart then continues to beat, the affected person wakes up again. However, this is not always the case – sometimes sudden cardiac death (secondary death) occurs. In cerebrovascular syncope, fainting is triggered by what is known as a tapping phenomenon. A tapping phenomenon manifests itself as follows: A vascular occlusion in the body causes an undersupply to the area behind it. This area therefore taps the blood supply of another area via another vessel. If blood is tapped from a vessel that supplies the brain, there may be an undersupply in the brain and consequently fainting.

Fainting in pregnancy

In pregnant women, fainting may occur from time to time, especially toward the end of pregnancy. The cause is the so-called vena cava compression syndrome. In this case, the pressure of the child on the inferior vena cava impairs blood flow to the heart. If the heart is no longer sufficiently filled with blood, this can cause fainting. The syndrome usually occurs in the last trimester of pregnancy, when the baby is already of an appropriate weight. Since the vena cava is located behind the uterus, unconsciousness is caused by prolonged lying in a supine position. Therefore, pregnant women should prefer to lie on their sides when lying down.

Nausea and dizziness as symptoms

Shortly before fainting, symptoms may appear that indicate impending syncope. Typical alarm signs include pallor, fatigue, ringing in the ears, sweating, dizziness, blurred vision and nausea. However, fainting can also occur without prior symptoms – this is usually the case with fainting spells that occur due to a disease of the heart.At the first symptoms of fainting, you should immediately sit down or, even better, lie down. Keep your legs elevated – this will help the blood flow back toward your head more quickly. If there is no place to sit or lie down nearby, it also helps to strongly tense the muscles. This compresses the vessels and forces the blood toward the heart. For example, you can do the following exercises:

  1. Cross your legs while standing and then tense the muscles of your abdomen, legs and buttocks.
  2. Put your hands in front of your chest, interlock your fingers, and then pull outward as hard as you can with both arms.
  3. Take a rubber ball or other object in your hand and knead it vigorously.

Fainting: what to do?

After fainting, you should always consult a doctor. He can make sure that it is actually a syncope and not a vascular circulatory disorder in the brain. The classic clinical picture in such a case is a stroke. In addition, the physician can check whether a disease of the heart – for example cardiac arrhythmia – is a possible cause. If this is the case, the disease must be treated accordingly. A pacemaker or defibrillator may then have to be inserted. However, do not take a fainting spell lightly, even if it has a harmless trigger. After all, loss of consciousness is always associated with risks – injuries to the head, broken bones and bruises can occur as a result of a fall. That’s why you should seek advice from your doctor on how to prevent another fainting spell. You can prevent fainting especially if it is orthostatic syncope. On the one hand, your doctor can prescribe medication to strengthen your circulation. On the other hand, you can also do something yourself to stabilize your circulation: Helpful, for example, regular exercise, alternating showers and drinking plenty of fluids.

React correctly

If you see a person fainting, it is important to react quickly and correctly. First, check to see if the person is actually fainting. To do this, it is best to tap her on the cheeks or gently shake her shoulders. Also make sure that she gets fresh air. If there is only a slight fainting, the person will wake up quickly. If the person does not wake up immediately when breathing on their own, they should be placed in the recovery position. If the person does not respond to shaking and and you cannot detect breathing, an emergency physician must be notified immediately and resuscitative measures initiated. Caution: when giving first aid to an unconscious person, keep in mind that there are other types of unconsciousness besides syncope. In diabetics, for example, fainting can also be caused by hypoglycemia shock.