Syncope (Fainting)

Also called: Passing Out, Syncopal Episode

Overview

What Is Syncope (Fainting)?

Syncope (SIN-kuh-pee), or fainting, is a temporary loss of consciousness. It happens when there isn't enough blood going to the brain because of a drop in blood pressure.

Top Things to Know

• Fainting is a short loss of consciousness that happens when not enough blood reaches the brain.
• Many kids feel dizzy, lightheaded, nauseated, or sweaty before they faint.
• Lying down, then sitting and drinking fluids may help stop fainting.
• Call a doctor if fainting happens often, causes an injury, or happens with chest pain or shortness of breath.

What Are the Warning Signs of Fainting?

Someone who is about to faint might:

• be dizzy, feel unsteady or lightheaded
• look pale
• have vision changes
• have a fast or irregular heartbeat
• sweat a lot
• have nausea and/or vomiting

Feeling like you’re about to pass out is called presyncope (pre-SIN-kuh-pee).

When Should I Call the Doctor?

Fainting is pretty common in kids and teens. Usually, there's no need to worry if your child or teen fainted:

• only once
• it was brief
• the reasons why are obvious (like being in a hot, crowded setting)

But if your child has a medical condition or is taking prescription medicines, it's a good idea to call the doctor.

Also call the doctor or get medical care if your child or teen:

• hurt themselves when they fainted (for example, hit their head really hard)
• has chest pain, palpitations (fast or irregular heartbeats), or shortness of breath
• had a seizure
• fainted during exercise or other physical activity
• has fainted more than once

When to Seek Emergency Care

Call 911 if your child or teen:

• is still unconscious after a few minutes
• passed out while exercising
• is having chest pain, trouble breathing, or a seizure

Causes & Prevention

Finding a Cause

The doctor will ask a few questions, do an exam, and might order some tests, such as:

• an EKG (a type of test for heart problems)
• a blood sugar test
• a blood test to check for anemia

Why Do People Faint?

Blood pressure can drop from dehydration, a quick change in position, standing or sitting still for a long period, or a sudden fear of something.

Common reasons for fainting include:

• Physical triggers. Getting too hot or being in a crowded, poorly ventilated setting are common causes of fainting. Sometimes just standing for a very long time or getting up too fast after sitting or lying down can cause someone to faint.
• Emotional stress. Emotions like fright, pain, anxiety, or shock can cause blood pressure to drop. This is the reason why people faint when something frightens them, like the sight of blood.
• Hyperventilation. A person who is hyperventilating is taking fast breaths. Carbon dioxide (CO₂) levels in the blood fall, causing blood vessels to narrow. Blood flow to the brain decreases, making a person faint.
• Medical conditions. Conditions such as heart problems, anemia, low blood sugar, or postural orthostatic tachycardia syndrome (POTS) can cause fainting.
• Pregnancy. During pregnancy, the body undergoes a lot of changes, including changes in the circulatory system. These may cause a woman to faint. And as the uterus grows, it can press on and partially block blood flow through large blood vessels, which can decrease blood supply to the brain.

Can Fainting Be Prevented?

If a person feels like they're going to faint, taking these steps might help stop it:

• If possible, lie down. This can help prevent a fainting episode, as it lets blood get to the brain, especially if the feet are propped up a bit. They should stand up again slowly when they feel better. Move to a sitting position for several minutes first, then to standing.
• Sit down with their head lowered forward between their knees. This also helps blood get to the brain, though it's not as good as lying down. When they feel better, they can move slowly into an upright seated position, then stand.
• Don't get dehydrated. Drink enough liquids throughout the day. Drink plenty of fluids before, during, and after exercise and in hot weather.
• Keep blood circulating. People who stand or sit for a long time should take breaks often and move around. Regularly tensing the leg muscles or crossing the legs can help improve blood flow.
• Avoid overheated, cramped, or stuffy environments, when possible.

How Can I Help My Child?

If your child or teen faints, help them lie down. Don't move them if they're injured from falling (that can make things worse). Instead, loosen any tight clothing, such as belts, collars, or ties. Propping their feet and lower legs up on a backpack or jacket also can help blood flow to the brain.

Someone who has fainted will usually recover quickly. Because it's normal to feel a bit weak after fainting, be sure your child lies down for a bit. Getting up too soon may bring on another fainting spell.