Understanding the Condition

It is vital to remember that each individual case is different. The individual that you are responsible for may not experience the exact symptoms detailed here and the causes may differ. Specific information can be gained from the individual and their family.


If someone loses consciousness for a short time, they are often said to have experienced a ‘blackout’. 

There are three main causes of ‘blackouts’: dysfunction of the cardiovascular system (syncope), dysfunction of the brain (neurological, as with epilepsy) or psychogenic dysfunction (mental, psychological factors).

Syncope [sin-co-pee]

‘Syncope’ is the medical term for a blackout that is caused by an interruption of the oxygenated blood supply flowing to the brain, resulting in sudden loss of consciousness, but with a quick and usually complete recovery.
The interruption to the blood supply can be caused by a problem with the heart’s rhythm, or by a problem in the regulation of blood pressure. 


Why does a syncopal episode happen?
Syncope can be triggered by a number of different stimuli, particular to the individual case; pain, heat and dehydration are examples.

For those affected by syncope, these triggers cause over-stimulation of the vagus nerve. This sets off an automatic reflex, causing a drop in blood pressure, or a stoppage, change, or reduction in rate of the heart’s rhythm, depending on the individual’s condition. This can cause a drop in the amount of blood pumped by the heart or a decrease in the amount of oxygen carried in the blood. Consequently, there is an insufficient flow of oxygenated blood to the brain, thus a blackout occurs.

What happens?
If the blood flow to the brain is tapered off- as when there is a fall in blood pressure- the individual often experiences warning signs such as light-headedness before they lose consciousness.

The heart can slow down and in some cases can come to an abrupt, complete, but temporary stop. In these circumstances, there is often no time for any warning symptoms. This type of syncopal episode can be more dramatic and those affected may experience fit-like ‘jerks’ and ‘spasms’. The eyes can roll in the head, the complexion can turn pale, the individual can become blue around the mouth and eyes, and in some cases, suffer incontinence.

This type of episode is often referred to as a reflex anoxic seizure. The symptoms may resemble an epileptic seizure but the causes of epilepsy and syncope are very different. It is vital that each is accurately diagnosed.

What are ‘near misses’?
The individual sometimes experiences ‘pre-syncopal’ warning signs, such as light-headedness, but they do not lose consciousness; they are able to ‘bring themselves back’. Near misses can easily go unnoticed.

Get in touch for more help and information

+44 (0) 1789 867 503info@stars.org.uk


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