A syncope is the clinical name given to a brief blackout (visual greyout) or an episode of fainting or momentary collapse.
It is triggered when the brain does not receive enough blood for a short period or when there is a slight decrease in the amount of oxygen reaching the brain, says Medical News Today and top US medical centre Johns Hopkins Medicine.
It can happen for a variety of reasons and is often sudden, leaving the person temporarily unaware of their surroundings, states Cleveland Clinic, ranked as one of the best hospitals in the US.
Cleveland Clinic also explains, in most cases, such episodes are harmless and resolve on their own, meaning no further medical care is required.
But when fainting is linked to underlying problems -- particularly those involving the heart -- it should never be ignored, as prompt treatment may be necessary.
What you need to know about a syncope
1. What Is Pre-Syncope?
Pre-syncope refers to the warning phase before an actual blackout occurs, that unsettling moment when your body signals that you might lose consciousness.
During this spell, a person may feel woozy or unsteady, experience waves of nausea, light-headed or notice their vision dimming or narrowing, as per Johns Hopkins Medicine and WebMD.
2. Who Is More Likely To Experience A Cardiac Syncope?
Cardiac syncope carries a greater level of risk, particularly among men and adults aged over 60.
The chances are also higher for people with a history of coronary disease, abnormalities in the heart's structure, previous rhythm disturbances, or weakened pumping ability of the heart, informs American Heart Association.
3. Syncope Triggers
Fainting can occur due to prolonged standing, sudden posture changes, heat exposure, certain medication, dehydration, blood donation, the sight of blood, emotional disturbances, low salt levels, heavy meals, excess caffeine or alcohol, or underlying issues affecting the heart, lungs, brain, nerves, or spinal cord, points out Cleveland Clinic.
4. Vasovagal Syncope
There are many kinds of syncopes, says Medical News Today and Cleveland Clinic, like orthostatic syncope (from standing, or getting up too fast) or hypoxic syncope (oxygen defiiciency to the brain).
The most common fainting response is a vasovagal syncope that happens when the heart rate and blood pressure drop suddenly, briefly reducing blood flow to the brain.
It is usually harmless and can be triggered by stress/anxiety among other factors, but injuries can occur if a fall happens during an episode, according to Mayo Clinic and Cleveland Clinic, both leading US hospitals.
5. Preventing Syncope
Staying well hydrated and maintaining adequate salt levels can reduce fainting risk, especially in those who are dehydrated or sensitive to certain medicines, states American Heart Association.
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