Sleep apnea is a sleeping disorder which is characterized by abnormal pauses in the breathing pattern, or instances of abnormally low breathing during sleep. Each pause between successive breaths is called an “apnea” – a word derived from the Greek word “apnoia” which means “without breath”. In case of normal breathing, the frequency of pauses is constant and regular. When the normal breathing pattern changes due to various reasons, and the intervals between successive pauses start becoming irregular, it leads to sleep apnea disorder. Each irregular pause of breath is referred to as “hypopnea.” So, in case of normal breathing, each interval or pause is termed as an “apnea”, while in case of abnormal breathing it is termed as “hypopnea.”
Symptoms of sleep apnea
Individuals suffering from the disorder often do not know they have it. Certain symptoms can ascertain whether the individual is suffering from the disorder. The major symptoms include:
- Restless sleeping patterns
- Choking or gasping during sleep
- Night sweats
- Feeling excessively sleepy during the day
- Snoring frequently and loudly
- Trouble in breathing during sleep
Other symptoms indicating a possible disorder are:
- Morning headaches
- Loss of memory
- Difficulty in learning new things
- Inability to concentrate for long
- Mood swings and/or personality changes
- Dry throat when awaking
- Frequent urination during the night
Causes of sleep apnea
The disorder generally occurs due to a fat buildup, or a loss of the muscle tone, especially during old age. In this particular disorder, the tracheal muscles (“trachea” is the windpipe), the soft palate muscles at the base of the tongue, and the uvula (“uvula” is the triangular shaped small fleshy tissue hanging from the center in the back of the throat) relax to a considerable extent and collapse during the breathing activity. In simple terms, the windpipe becomes taut, or the layers of the windpipe adhere which restricts the flow of air into the lungs. The disorder can also occur due to a malfunction of neurons controlling the breathing process during sleep. This sleep disorder can be diagnosed by an overnight polysomnogram test – a sleep test which is extensively used to detect sleeping disorders and related problems.
Effects of sleep apnea
Even though the sleep disorder might appear to be a common and not-so-serious, it can lead to some serious health problems. If left untreated, the disorder can result in:
- Sexual dysfunction
- High blood pressure
- Irregular heart beats
- Coronary Heart Disease
- Chronic Heart Failure
- Worsening of Attention Deficit Hyperactivity Disorder (ADHD)
Types of sleep apnea
There are three types of sleep apnea:
- Obstructive sleep apnea (OSA)
- Central sleep apnea (CSA)
- Mixed sleep apnea (MSA)
Even though all the three types of sleeping disorders differ as far as their causes and treatment is concerned, one aspect remain common – some parts of the respiratory system narrow down and impair the percentage of oxygen reaching the subject’s lungs.
Obstructive sleep apnea (OSA)
This is a highly common form of the disorder found in majority of the individuals suffering from sleeping disorder. Obstructive sleep apnea is a physical disorder. This form of disorder is typically characterized by individuals who have:
- More weight (overweight)
- Small jaw line
- A small air passage in the trachea (windpipe)
- Large tongue
The main cause of OSA is the same as stated above for sleep apnea. The condition can further worsen if the subject consumes alcohol, ingests tranquilizers and sleeping pills.
Central sleep apnea (CSA)
This is a comparatively rare form of the sleeping disorder in which the tracheal muscles do not sag to much extent, and the air passage remains large enough so that enough air can pass through. However, in this particular disorder the diaphragm and the chest muscles temporarily fail to function effectively, which results in reduced oxygen levels in the blood. The decreased oxygen level affects normal metabolic working of the body, and the brain too receives less oxygen so the subject suffers from memory loss, slow learning, sluggish reflexes, and inability to concentrate for long.
Mixed sleep apnea (MSA)
In very rare cases, some individuals experience both obstructive sleep apnea and central sleep apnea simultaneously. In such cases, both the sleep disorders manifest themselves by interspersing with each other, and the individual may experience the effects of either of the disorders at one particular instance, or a combined effect of both. The pathological or psychological effects of this disorder cannot be predetermined or ascertained since many factors affect its manifestation.
Sleep apnea treatment
The treatment for the sleep disorder varies in accordance to the level to which the individual is suffering from it. Generally, the treatment can be administered in the form of therapies and surgeries depending upon how much the disorder is affecting the individual. The treatment consists of:
Continuous positive airway pressure (CPAP)
This therapy is generally used if the individual has moderate to severe sleep disorder. The therapy consists of a machine which delivers air (oxygen) through a mask placed over the nose while asleep. The air pressure remains greater than that of the surrounding air, and is just strong enough to keep the air passages open.
Adjustable airway pressure devices
In this therapy, a special type of air pressure device automatically adjusts the air pressure and oxygen levels while asleep. The basic functioning of the device is similar to that used for CPAP therapy, however it is a more advanced model and supports bi-level positive airway pressure (BPAP). The device provides more pressure while inhaling and reduces the pressure while exhaling.
Adaptive servo-ventilation (ASV)
This airflow device learns and understands the normal breathing pattern, and subsequently stores the information in a built-in computer. While asleep, the machine regulates the air pressure to normalize the breathing pattern, and prevents any pauses in the breathing activity. ASV is more successful than CPAP while treating central sleep apnea in some individuals.
This therapy involves wearing an oral appliance specially designed to keep the throat “open”. Oral appliances are easier to use. Some appliances are specially designed to keep the throat open by bringing the jaw forward, which can at times even relieve snoring as well as prevent mild obstructive sleep apnea.
The main objective of sleep apnea related surgery is to remove any excess tissues from the nose or the throat which may be causing the blockage of the air passage. The surgical options include:
During this surgical procedure, excessive tissue is removed from the rear of your mouth, and from the top of the throat. At times, the tonsils and adenoids are also removed. This type of surgery can be successful in preventing snoring, however, from clinical findings it is observed to be less successful in treating sleep apnea, since the tissues farther down the trachea (windpipe) may still block the air passage. UPPP procedure is generally performed in a hospital, and requires administration of general anesthesia.
In this procedure, the jaw is moved forward from the remaining facial bones. This enlarges the space behind the tongue and the soft palate, reducing the air obstruction. This procedure may require the services of an oral surgeon and/or an orthodontist, and may be combined with other surgical procedures to improve the likelihood of success.
This is a critical surgery, and it is only recommended when other treatments fail and the subject has severe or life-threatening sleep apnea disorder. In this procedure, an opening is made in the neck and a metal or plastic tube is inserted into the trachea through which we breathe. The opening is covered during the day, and at night, it is uncovered to allow air into the lungs. The tube helps to bypass the blocked air passage.