(LifeWire) - Your child faints. Is a serious condition the cause? Not usually.
Seeing a needle, or blood, or some other common object of childhood fear can trigger the generally harmless event we call fainting, but in medical terms doctors call it "vasovagal syncope."
Here's how it works:
The vagus nerve, which runs all the way from head to abdomen by way of the neck and chest, can be overstimulated by physical or psychological distress.The vagus nerve is a part of the "autonomic" nervous system, which controls involuntary bodily actions like breathing and heart rate -- all the automatic actions that have to take place without our being aware of them, behind the scenes, to keep us alive.
Stress on the vagus nerve, and the results are that:
- the heart pumps more slowly,
- blood vessels in the legs expand,
- less blood and the oxygen it carries go to the brain,
Studies in young medical students have shown that up to a quarter of the males and half of the females had experienced at least one fainting episode.
Although fainting is seldom serious in children or adults, it should always be brought to a doctor's attention. In rare cases, it can signal a heart condition such as irregular heartbeat, a structural problem in the heart, cardiac inflammation or a valve malfunction.
When vasovagal syncope is suspected, a tilt table evaluation is often performed. Heart rate and blood pressure are monitored while the person being tested is strapped to a mechanized table that is placed into an upright position for 20 to 30 minutes.
The test is not perfect, but if you faint while the table is upright, it is likely that vasovagal syndrome is the correct diagnosis of your condition.
Treatment for the vasovagal syndrome varies by patient and doctor because there is no settled agreement on what constitutes optimal therapy for this condition. Preventive measures include increasing fluid and salt intake to boost blood pressure, and the prescription of any of a variety of medications.
Drugs that alter blood pressure are often prescribed. And sometimes patients are given antidepressants, which act on the central nervous system and can prevent fainting.Here is a more detailed list of potential triggers that may lead to vasovagal fainting:
- Urinating or having a bowel movement, especially if a significant amount of strain is involved
- Coughing strenuously
- Fear of medical procedures
- Severe pain
- Heat exposure or dehydration
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