By Adam Powell, MD, pediatric cardiologist at Cincinnati Children’s
Pediatric Fainting (Syncope):
Fainting (also called syncope) is very common in the teenage and young adult years. Around 20% of young adults report having passed out at least once in their life. Fortunately, fainting is rarely a sign of a dangerous condition. Despite being common and rarely dangerous, fainting can cause a great deal of worry and stress for the affected child and their parents, who often fear that people who faint have an increased risk of sudden death. The most common cause of non-cardiac syncope is called vasovagal syncope. Other non-cardiac causes of syncope can include seizures, neurological problems and stress.
Vasovagal Syncope: Vasovagal syncope (or neurocardiogenic syncope) is the most common cause of non-cardiac fainting and accounts for more than 90% of fainting in childhood. It is caused by a sudden drop in blood pressure. For a brief moment, the brain does not have enough oxygen, which leads to fainting. Sometimes this can occur because of changes in the normal involuntary (autonomic) reflexes, which can lead to the blood vessels dilating and decreasing blood pressure when they normally should not. This is exceedingly common in the teen years and is likely due to a combination of rapid height change, hormonal changes during puberty, dietary choices and increased stress. Children and young adults who experience this often describe feeling dizzy, lightheaded or having muffled hearing prior to passing out. It tends to occur when going from sitting to standing or during periods of prolonged standing such as in the shower or in church.
While frightening, this problem is not dangerous and is highly treatable. The majority of children with this type of fainting will outgrow their symptoms. The vast majority of children who faint will have dramatic improvement by increasing their water intake (goal of 80 to 100 ounces a day). Additional dietary changes that can lead to improvement include limiting caffeine, increasing salt intake and eating three meals a day. Regular exercise, particularly strength training of the lower extremities can result in improvement in symptoms. Occasionally the use of compression garments can help. Stress reduction techniques and counseling can help manage the stress and anxiety that these events can cause.
Cardiac-related Causes of Syncope: There are a few different cardiac causes of syncope. For one, it can be due to abnormal heart rhythms (arrhythmias). These often present as sudden fainting without symptoms or sometimes with palpitations immediately prior to the syncope. Often, there are multiple family members who have a cardiac diagnosis, pacemaker or implantable defibrillator. Additionally, an EKG can help to diagnose this type of syncope. An additional cause of fainting is due to a blockage of blood flow like that seen in more complex heart conditions, such as aortic valve disease or hypertrophic cardiomyopathy. This type of fainting typically happens during exercise and is sudden without many preceding symptoms. Often, there can be abnormalities such as murmurs present in the physical exam, in a child who faints due to this cause. Lastly, fainting can occur in people who have reduced heart function, such as in other types of cardiomyopathy or anomalous coronary arteries. This type of syncope also tends to happen only with exercise, and the child may also have progressive fatigue with exercise.
Reasons to See a Physician: In addition to the description above, the below symptoms should warrant an evaluation by a physician:
Fainting that occurs during exercise
Fainting that occurs without warning
Fainting that results in a severe injury
Fainting and a family history of sudden cardiac death at a young age
Ultimately, most children and young adults do not have a life-threatening reason for their fainting. Most fainting is improved by increasing water intake and other various dietary and lifestyle changes. Additionally, the majority of children and young adults with syncope will improve by themselves. Anyone who faints during exercise or suddenly without warning, has a serious injury as a result of their fainting, or faints while also having a family member with previous sudden cardiac death, should see their physician to see if a referral to a cardiologist is needed.
About the Author: Cincinnati Children’s now offers a pediatric heart clinic at Rush Memorial, led by Dr. Adam Powell, who is a pediatric cardiologist. Dr. Powell specializes in general cardiology and pediatric exercise cardiology and has published multiple papers regarding the exercise performance of children with and without heart disease. Prior to his time at Cincinnati Children’s, he served in the United States Air Force as a general pediatrician for 7 years. When he is not doctoring, Dr. Powell lives an active lifestyle involving early morning runs, coaching youth sports and chasing his 4 young children.