What is a Blackout?

A Blackout is a transient loss of consciousness. Synonymous terms are faint, collapse, and syncope.

How common are Blackouts?

Blackouts are very common, occurring primarily in two age groups: the teenage years and older age. About 40-50% of all people will have a blackout or near blackout event.

What are the Causes?

There are many causes of blackouts. Most cases are due to common faints caused by a short-term reduction in blood pressure in the brain.

Abnormal heart rhythms (arrhythmias) can cause blackouts; in that case, things are more serious.

Neurological disorders such as epilepsy and cerebrovascular events-strokes are not uncommon and have a completely different presentation but need immediate attention.

Psychogenic blackouts are caused by excessive stress that controls the brain and makes the body collapse without an organic pathological cause.

Are blackouts dangerous?

Most Blackouts are entirely benign and, hence, not dangerous. Some require treatment with a good long-term prognosis. Few can be life-threatening and need urgent attention from a blackout specialist (Cardiologist/Electrophysiologist, and/or Neurologist)

Do I need to have any tests?

Most people can be reassured after history and examination by a specialist. In that case, no tests are needed.

In general, it is a good idea to have an ECG (Electrocardiogram) and an ECHO (echocardiogram) as these two tests are related to a good long-term prognosis if they are normal.

If symptoms suggest an arrhythmia, i.e., palpitations, collapsing in a sitting position, a monitor can be fitted to record the heart rhythm over a prolonged period.

If a blackout occurs during exercise, then an Exercise Tolerance Test is an option.

If a Neurological cause is suspected, an EEG (Electroencephalography) or brain

Imaging (CT, MRI) might be required.

How can Blackouts be prevented or treated?

You can manage Blackouts in various ways, but this depends on the cause. The specialist can identify the cause, and the treatment can then vary from lifestyle measures (such as increasing salt and fluid intake and avoiding prolonged standing) to medications (antiepileptics) or implantable devices (pacemakers, defibrillators).