Obstructive Sleep Apnea
Sleep apnea is the term used for periods in which a person temporarily stops breathing while asleep. Obstructive sleep apnea occurs when something is blocking the airway. It is the most common type of sleep apnea.
What is going on in the body?
Obstructive sleep apnea occurs when tissue in the upper airways blocks the breathing passages. The blockage may come from a collapsed uvula. The uvula is the soft tissue that hangs down at the back of the throat. Large tonsils or other excess tissue may also block the airway.
When the muscles relax during sleep, excess tissue can drop into the air passage and interrupt breathing. The person continues to try to breathe around the blockage but cannot take in enough oxygen. Carbon dioxide builds up in the person's blood. This problem corrects itself as soon as normal breathing is restored.
What are the causes and risks of the condition?
Obstructive sleep apnea occurs when the airway is blocked by excess tissue. Seventy percent of individuals with this problem are overweight. Symptoms often improve or go away entirely if some of this excess weight is lost.
Other risk factors for sleep apnea include:
- drinking excessive amounts of alcohol
- enlarged tonsils
- lung diseases, such as emphysema
- sleeping on the back
- smoking cigarettes
- using sleep medications
Obstructive sleep apnea occurs 3 to 20 times more often in men than in women. The women who do get it are most often past menopause.
What can be done to prevent the condition?
Weight management can prevent some cases of obstructive sleep apnea. It may be helpful for people with narrow breathing passages to have their tonsils and adenoids removed.
How is the condition diagnosed?
If a person exhibits symptoms of obstructive sleep apnea, a sleep study
, called a polysomnogram (PSG), may be recommended. This test measures the following body functions during sleep:
- airflow and respiratory effort
- blood oxygen levels
- blood pressure and heart rate
- electrical activity in the brain
- eye movement
- muscle movement
A multiple sleep latency test (MSLT) measures the speed of falling asleep. An arterial blood gas test may also be performed to check levels of carbon dioxide and oxygen.
Long Term Effects
What are the long-term effects of the condition?
Sleep deprivation can lower a person's quality of life and increase the risk for injuries. Up to 50% of the individuals with obstructive sleep apnea have high blood pressure. They are also at increased risk for the following disorders:
arrhythmia, or irregular heart rhythm, which may be fatal
cor pulmonale, a condition in which the heart is so weakened that it cannot pump blood through the lungs
pulmonary hypertension, or high blood pressure in the lungs
right ventricular hypertrophy, that is, enlargement and weakening of the right side of the heart
What are the risks to others?
Obstructive sleep apnea is not contagious and poses no risk to others.
What are the treatments for the condition?
Treatment is focused on reducing airway blockage and increasing the amount of oxygen in the body. The first step is often a serious attempt at losing weight. Dental appliances may be used to reposition the tongue and lower jaw. It is also crucial to avoid alcohol and sleeping pills.
If these measures do not help, the person may need a continuous positive airway pressure (CPAP) machine. The individual wears a mask over the nostrils and/or mouth that pumps in pressurized air. This increases the amount of oxygen entering the lungs and also relieves the symptoms of obstruction. The technique can be used with or without supplemental oxygen.
A number of surgical procedures are available. One of the most common, uvulopalatopharyngoplasty, abbreviated as UPPP, is a type of surgery that removes excess tissue at the back of the throat. If all other methods fail, a tracheostomy may be done. This involves cutting a small hole in the neck surgically, through which the person can breathe.
What are the side effects of the treatments?
If the person responds well to treatment, there are no side effects. The individual will sleep better and symptoms will disappear.
What happens after treatment for the condition?
If the sleep apnea is improved by weight loss, it is important that the individual keep the excess weight off. Some treatments, such as the use of a CPAP machine, can be lifelong.
How is the condition monitored?
Any new or worsening symptoms should be reported to the healthcare professional.