Suddenly, you are no longer in control of your senses and all perception of the outside world disappears: fainting (Latin: syncope) is a frightening condition. There are some typical situations in which fainting is particularly common in humans. For example, fainting occurs more often with very low blood pressure or states of shock. But why do people faint in the first place? What processes in the organism are responsible for this?
Disturbance of cerebral blood flow as a cause of fainting.
A momentary loss of consciousness is called fainting because during this time one is “without power” over one’s mental and, as a result, physical processes. The most common cause of fainting is a momentary disturbance in cerebral blood flow.
The brain is a sophisticated and complex system, which reacts immediately to the slightest irregularity. The body knows how to protect itself and is programmed to maintain life-sustaining bodily functions in emergency situations. Thus, it reduces its higher brain functions to maintain processes essential for survival, such as breathing and heartbeat.
Possible cause: malfunction of a nerve center.
A short-term disturbance in cerebral blood flow may be caused by a malfunction of one of the nerve centers that control heart function and are located at the heart and the heart’s arteries. This is also where the center of blood pressure regulation is located. Here, malfunctions result in a brief drop in blood pressure.
Other causes of fainting
Syncope (brief loss of consciousness or fainting) differs depending on the affected nerve center. A distinction is made between:
- Vagovasal syncope (unconsciousness occurs due to a drop in blood pressure and pulse).
- Micturition syncope (the unconsciousness occurs during urination).
- Cough syncope
- Orthostatic syncope (unconsciousness occurs as soon as the affected person moves from horizontal to vertical) and
- The Adam Stokes seizure, in which our biological pacemaker in the heart briefly stops.
In clinical shock, fainting occurs due to blood loss after injury or by blood vessels becoming slack and the venous return of blood to the heart ceases.
To determine the medical cause of fainting, it is crucial to determine whether the fainting was followed by a fall, because a fall is typical of syncope, generalized seizures in epilepsy, as well as hypoglycemia in diabetes or increases in intracranial pressure, as can wrap up after bleeding in an accident.
Fainting and memory loss
The affected person’s memory is also affected by the brief shutdown of brain functions. Memory loss (amnesia) depends on the length of time the person was unconscious. The longer one has been unconscious, the more likely there will be a gap in memory, which in extreme cases can extend to several days.
Preventing fainting
If you suspect you will pass out in a few seconds or minutes, you should sit on the floor if possible. This will help you avoid injuries from falling. In addition, you should elevate your legs to allow blood to flow back toward your brain.
Help for fainting
If you are present while another person passes out, the best way to help them is to place them in the recovery position and check their breathing and pulse. Elevating the feet can also be helpful. An emergency physician should be called if the person does not regain consciousness quickly or has an irregular pulse or breathing. In addition, the emergency physician can also get to the bottom of the cause of the fainting.