What I notice in my clinical practice is that many of my patients who complain of feeling faint have overbreathing or hyperventilation.
We normally breathe automatically but external events or stresses can change our breathing pattern and make us feel short of breath, anxious, or ready to faint. When this happens, it’s called hyperventilation, or overbreathing.
We breathe in oxygen and breathe out carbon dioxide. In situations where there is overbreathing, we will lose too much carbon dioxide in the air that we breathe out. This causes carbon dioxide level in the blood to drop to a low level, and the blood vessel in the brain will then constrict, causing us to feel faint or giddy. The quick solution here is to learn to slow down our breathing so that the carbon dioxide level in the blood will become normal again.
Hyperventilation happens most often to people 15 to 55 years old. It can come about when you feel nervous, anxious, or stressed. It may happen more often when a woman is pregnant, but the problem usually goes away on its own after the baby is born.
Fainting happens when a person loses consciousness for a short amount of time because his brain is not getting enough oxygen. A fainting spell generally lasts from a few seconds to a few minutes. Feeling lightheaded, dizzy, weak, or nauseous sometimes happens before the person faints.
Fainting can be triggered by a number of factors, including severe pain, fear or other emotional trauma, a sudden drop in blood pressure, low blood glucose level, hyperventilation, dehydration, standing in one position for too long, sudden change of posture, physical exertion in hot temperatures, coughing too hard, straining during a bowel movement, fits, drinking alcohol, etc.
Three common types of fainting are encountered in clinical practice:
- The first is vasovagal syncope, where the vagus nerve is involved. It can be triggered by emotional trauma, stress, the sight of blood, or prolonged standing.
- The second is carotid sinus syncope where the carotid artery in the neck is constricted, usually after turning the head to one side or wearing a collar that is just too tight.
- The third is situational syncope, which occurs due to straining while coughing, urinating, or passing motion.
