What is Sleep Apnea?

Firstly described in 1965, sleep apnea is a potentially life-threatening disorder that is far more common than expected. It is characterized by brief interruptions of breathing during sleep. It owes its name to a Greek word, apnea, meaning "want of breath."

There are two types of sleep apnea: central and obstructive.

Central sleep apnea, is relatively less common. It occurs when the brain fails to send the appropriate signals to the breathing muscles to initiate respirations.

Obstructive sleep apnea (OSA) is very common. It occurs when air flow cannot get into or out of the person's nose or mouth despite the effort of breathing continues.

In a given night, the number of involuntary breathing pauses or "apneic events" may be as high as 20 to 30 or more per hour. We have seen a patients stop his own breathing more than 60 times per hours. These breathing pauses usually accompany with snoring. Snoring occurs between apnea episodes. However, not everyone who snores has OSA. Choking or choking sensation is another common symptom for sleep apnea. The frequent interruptions of deep, restorative sleep often lead to early morning headaches and excessive daytime sleepiness.

Early recognition and treatment of sleep apnea is important because it may be associated with irregular heartbeat, high blood pressure, heart attack, and stroke. Each single condition can be lethal or causing severe disability.


Why Sleep Apnea?
Mechanical and structural problems in the airway can cause interruptions of breathing during sleep. In some people, apnea occurs during the throat muscles and tongue relax in sleep and it partially block the opening of the airway.

When the muscles of the soft palate at the base of the tongue and the uvula (the small fleshy tissue hanging from the center of the back of the throat) relax and sag, the airway becomes blocked. It makes the breathing laborious and noisy. Sometimes, it just stopped altogether.

Sleep apnea also can occur in obese people who has excessive amount of tissue in the airway and makes it narrowed. The narrowed airway makes the air cannot easily flow into or out through the airway. This results in heavy snoring, periods of no breathing, and frequent arousals causing abrupt changes from deep sleep to light sleep. All these is unknown to the patients with sleep apnea. The condition can be aggregated by ingestion of alcohol and sleeping pills.

WHO GETS SLEEP APNEA?

Sleep apnea can occur in ALL age groups and both sexes, although it is more common in men. It has been estimated that as many as 18 million Americans and 3-4% of Hong Kong population are suffering from sleep apnea.

People most likely to have sleep apnea include those who snore loudly and also are overweight, or have high blood pressure, or have some physical abnormality in the nose, throat, or other parts of the upper airway. Sleep apnea seems to run in some families, suggesting a possible genetic basis.

WHAT HAPPEN DURING APNEA?

The result of stop breathing (apnea) is reducing levels of oxygen and increasing levels of carbon dioxide. The reduction in oxygen and increase in carbon dioxide can alert the brain to resume breathing and cause an arousal (waking up from sleep). During each arousal, a signal is sent from the brain to the upper airway muscles, to open the airway and breathing can be resumed. It is often associated with a loud snort or gasp. These frequent arousals prevent the patient from getting enough restorative, deep sleep.


Because of the serious disturbances of normal sleep, sufferers of sleep apnea often feel very sleepy during the day. It affects their concentration and daytime performance.

The consequences of sleep apnea range from annoying to life-threatening. Here is an abbreviated list of effects of sleep apnea:


Depression

Irritability

Sexual Dysfunction

Learning and memory difficulties

Falling asleep while at work, on the phone, or driving

Arrhythmia (irregular heartbeat)

High blood pressure

Heart attack

Stroke

All you Need To Know About Sleep Disorder

Obstructive Sleep Apnea: Obstructive sleep apnea, also called OSA, is the result of an airway blockage. The most common cause of this blockage is a collapse of the soft tissue at the rear of the throat during sleep, which can also be caused by tongue, tonsil or uvula positioning. OSA is the most common type of apnea.

Central Sleep Apnea: Central sleep apnea is caused by a failure on the part of the brain to control breathing. With Central sleep apnea there is no physical blockage but the result is still an inability to breath.

Mixed Sleep Apnea: Mixed sleep apnea occurs when the apnea is caused by a combination of physical blockage and a stoppage in breathing caused by a lack of signal from the brain.

Consequences of Sleep Apnea

Depending on the severity of the apnea, and the duration for which the condition goes untreated, the condition can lead to several severe medical problems. In the short term, patients with apnea often experience extreme fatigue, memory problems and general impairment that can lead to secondary health issues such as car crashes. Longer term, untreated apnea has been directly linked to high blood pressure, stroke and other cardiopulmonary disease as well as weight gain, impotence and headaches.

Symptoms of Sleep Apnea

Often, people with sleep apnea are unaware of the condition for a long time since they may not realize that they are waking regularly during the night. Many times, someone else sleeping in the home can help identify symptoms of sleep apnea before the person suffering from the condition can.

Some of the symptoms of this common condition include:

Heavy snoring
Gasping or pauses in breathing during sleep
Extreme sleepiness or fatigue during the day

Some related secondary symptoms may include:
Morning headaches
High blood pressure
Weight Gain
Heartburn
Insomnia
Excessive perspiration during sleep
Dry mouth in the morning

Diagnosis of Sleep Apnea

If you have symptoms of sleep apnea, you should speak with your doctor. Your doctor can refer you to a sleep specialist for a sleep study. During the study, sleep technicians will monitor your sleep and any waking that occurs. They have specialized equipment that can not only diagnose apnea, but help determine the best course of treatment.

Treatments for Sleep Apnea

Most commonly sleep apnea is treated by having the patient sleep with a C-PAP. A C-PAP (continuous positive airway pressure) is a machine that blows a constant stream of air into the patient's airway keeping it from being obstructed. The patient wears a mask either over the nose or over both the nose and mouth that funnels the airflow. Another type of machine known as a Bi-level is sometimes used for patients with severe apnea.

There are also surgical treatments for obstructive sleep apnea, where the structure of the throat is modified in order to prevent blockage. Surgery is usually only recommended for those who are unable to use a C-PAP or other non-surgical measures.

Patients may also see improvement in apnea by losing weight, and by avoiding alcohol and sleep medications. In addition, people are more likely to have apnea episodes when they sleep on their backs, so side sleeping can help.