Synonyms
Vasovagal syncope, blackout, fainting, circulatory collapse, collapse, blackout before eyes
Definition
Vegetative syncope is a short-term unconsciousness due to an intrinsically harmless maladjustment of the circulation through the autonomic nervous system in case of emotional stress, exhaustion, long periods of standing still (guardsman) or pain. Due to an excessive activation of the vagus nerve, the veins dilate and the blood, following the force of gravity, sinks into the legs. At the same time, vagus activation reduces the heart‘s pumping capacity, the circulation is unable to provide the brain with an adequate blood supply, resulting in a brief fainting. Since sufficient blood reaches the brain again when lying down, the unconsciousness is usually short-lived. However, because syncope (= unconsciousness) can also be a symptom of a serious underlying disease, in certain cases extensive diagnostics are performed.
Epidemiology
Vegetative or vasovagal syncope accumulates in childhood and adolescence and in old age. Overall, the frequency of fainting fits of any kind is reported to be 0.7% per year, the most common cause being vegetative dysregulation.
Symptoms
The signs can be paleness, trembling, cold sweat, flickering or blackening before the eyes or a ringing in the ear. In a fainting spell, the affected person sinks to the ground, rarely there are twitches or cramps in the limbs. The unconsciousness lasts only for a short time, and the affected persons are quickly reoriented afterwards.
Differential diagnosis
Especially in elderly people with pre-existing conditions, vegetative syncope is an exclusionary diagnosis because a fainting spell can also be a symptom of a serious illness. Possible organic causes of syncope can be
- Cardiovascular system: low blood pressure, orthostatic dysregulation (misregulation of cardiovascular coordination when getting up), cardiac arrhythmia, heart attack, heart failure, pulmonary embolism
- Brain: circulatory disorders such as TIA, PRIND (precursors of stroke), stroke, cerebral hemorrhages, cerebral pressure increases, epilepsy
- Metabolic diseases: Metabolic derailment, hypoglycaemia, anemia, mineral imbalances, medication
