How common is fainting for kids?

Today’s guest blogger is Gina Baffa, MD, a pediatric cardiologist and director of echocardiography at Nemours Cardiac Center, Alfred I duPont Hospital for Children in Wilmington, Del.

Fainting episodes are alarming, but not uncommon in children, especially teens. About 20 percent of children and adults will experience one or more fainting spells, most of which are benign.

What happens when you faint? When someone faints, it's usually because changes in the nervous system and circulatory system cause a temporary drop in the amount of blood reaching the brain. When the blood supply to the brain is decreased, a person loses consciousness and falls over. After lying down, a person's head is at the same level as the heart, which helps restore blood flow to the brain. A person then usually recovers after a minute or two.

Why do people faint? Here are some common reasons:

  • Physical triggers: Getting too hot or being in a crowded, poorly ventilated setting are common causes of fainting in teens. People can also faint after exercising too much or working out in excessive heat and not drinking enough fluids because they’ve become dehydrated.
  • Emotional stress: Emotions like fright, pain, anxiety, or shock can affect the body's nervous system, causing blood pressure to drop. This is the reason why people faint when something frightens or horrifies them, like the sight of blood.
  • Hyperventilation: A person who is hyperventilating is taking fast breaths, which causes carbon dioxide (CO2) to decrease in the blood. This can make a person faint. People who are extremely stressed out, in shock, or have certain anxiety disorders may faint as a result of hyperventilation. 

How do I know if a fainting episode is serious? Circumstances are key with syncope, the medical term for fainting. Was the patient sitting, standing, changing position from sitting to standing, or exercising at the time the event occurred? Syncope when upright or with a change in position is often related to a disturbance in how the nerves regulate the cardiovascular system, which has the effect of lowering blood pressure.  This is a benign condition.

Fainting that occurs at the sight of blood or something gory is also usually benign. In addition to these circumstances, it’s important to know what the child felt just before passing out.  Did they have some warning symptoms? Did bystanders notice any repetitive movements of the extremities or face to suggest a seizure? How much fluid was taken prior to the incident can also provide clues. If the patient was strenuously exercising and then fainted, this is of greater concern and will require additional testing.

How is fainting treated? Most patients with benign fainting episodes can be treated with increased oral fluid intake. We recommend at least 64 ounces of decaffeinated fluids throughout the day, mostly water but also some 100 percent juice or skim milk. As a rule of thumb, kids should drink two 8 oz. glasses in the morning, then at lunch, after school, and with dinner.

We give children notes allowing them to carry a water bottle during the school day.  If they are in sports, they need to pre-hydrate before the event and re-hydrate afterwards. If the fainting is repetitive despite increased fluid intake, then additional testing or medications may be considered.

See your pediatrician If your child has experienced multiple fainting episodes, if the fainting happened during exercise, or if it was accompanied by involuntary movements that may suggest seizure.

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