What is it?
The syndrome of Obstructive Sleep Apnea (OSA) is a breathing sleep problem that is characterized by repeated episodes of interrupted breathing, although the effort of breathing is still there. Obstructive apnea is a complete cessation of airflow through the nose and the mouth up to 10 seconds or more. A typical patient will have 5 or more apneas per hour of sleep. Among these breathing pauses, often the patient snores loudly. As night time sleep is subject to frequent interruptions, the patient usually have excessive daytime sleepiness.
The OSA can severely affect life quality and increase the risk of cardiovascular disease and sudden death. Furthermore these patients have more tendency to work and traffic accidents.
Being a serious and potential fatal situation, should be diagnosed and treated effectively.
There is another type of sleep apnea, central apnea, in which the airway is not obstructed, and that occurs when the brain fails to send the diaphragm stimulus for breathing. A central apnea is much less common than obstructive.
How it manifests itself?
The main manifestations of OSAS are during sleep time, and the patient are not aware of them. During the day, there are co-workers, family or friends who notice that the person falls asleep in less appropriate times. Since evolution is too slow, it can take several years, the patient only has the perception of the problem when a serious situation occurs (falling asleep when driving, industrial accident). It is very important that a person who shares the bedroom with the patient can testify the visible effort to breathe, the snoring characteristics and interruptions of breathing during the sleep time of the patient.
The snore (snoring) is the most important night symptom of OSA. Become with the vibration of the soft tissues of the throat when a person inhales, opening and closing the passage of air, alternating. The intensity and the tone of snore depend on the amount of air flowing in the airway, and the speed of the vibration.
In addition to the snore, the syndrome of sleep apnea can manifest itself during the night in a restless sleep with several interruptions, choking sense of crisis, urinate several times a night, increase sweating, gastroesophageal reflux (passage of stomach acid into the esophagus). Patients often complain of insomnia, as well as headaches, fatigue, and dry mouth upon waking.
Drowsiness is the most notorious day symptom in OSA and it’s a result of a fragmented and more superficial night sleep. A normal sleep has its own architecture evolving cycles throughout the night, going from light sleep to deep sleep, ending in the dream phase of sleep or REM sleep. In a patient with OSA, this normal sleep architecture can be changed by frequent awakenings.
During the day the OSA can also be manifested by a lack of concentration and performance, including at work or in driving cars. Sometimes, there’s memory loss and mood swings or personality (depression, irritability), and sexual disorders.
About 50% of people that suffers from sleep apnea have hypertension. The risk of heart attack or brain damage is huge on people with OSAS.
How often?
The OSA may exist at any age, even in children. It is estimated that in middle age (between 30 and 60 years) 2% of women and 4% of men have obstructive sleep apnea with daytime sleepiness.
People who are overweight, hypertension or have anatomical abnormalities of the nose or throat have more tendency to snore and to have OSA.
What are the causes?
When a person falls asleep, the pharyngeal muscles relax and become flabby, which leads to partial collapse and obstruction of air passageways (upper airways) causing restriction of snoring, breathing obstruction or complete obstruction (apnea). Nevertheless, the patient makes persistent efforts to breathe through the chest and abdomen muscles, particularly the diaphragm. Each time an apnea occurs there is a decrease of oxygen in the blood.
After a while (10-60 seconds), respiratory effort to overcome the obstruction leads to an alert to the brain, and a momentary awake occurs, which restores the tone of the muscles of the upper airways. So, the apnea is interrupted by this brief awake. Then the patient starts breathing again until he falls asleep again, and again a relaxation of the muscle of the pharynx occurs. This cycle of events can be repeated hundreds of times per night.
Structural conditions of the nose (septal deviation) or congestion due to allergies or a common cold, may, separately or in combination, increase the collapse of airways, increasing the snoring. Nasal obstruction leads to mouth breathing and to a displacement of the lower jaw, which make the base of the tongue touch the back of the throat, favoring apnea.
Obesity that causes fat deposits on the neck, the increase size of the tongue and the uvula ("bell"), certain jaw deformities (chin), tonsils and adenoids bulky, favor the development of OSA. Some drugs (tranquilizers, antihistamines), alcohol, inhaled irritants (cigarette smoke) have similar effect. Also some endocrine diseases predispose OSA.
How to prevent?
Prevention measures are all those that can amend the risk factors for sleep apnea: the removal of tonsils and adenoids in children and the reduction of weight in obese adults are the most important. The treatment of the nasal and pharyngeal anomalies or facial bone defects, as well as the avoidance of alcohol, sleeping pills and tobacco can prevent the beginning or the improving of sleep apnea.
What is evolution?
Snore is very common in both genders, but is twice common in males. Approximately 30% of 30 years old men and about 40% of people of both genders, with 50 years old, suffer from snoring.
It is common to snore and don’t have the need to do an OSA treatment; this only happens in 10-35% of cases. However there is always a motive to be concerned because, in any case, is an unnatural breathing during sleep time.
It is believed that snore can develop into OSAS. The typical story begins in the mid-20s with a continuous but innocent snoring. With age passing by and with some overweight, when they turn 40, the snoring is already intense but intermittent, because of the momentary awakenings. When you arrive to the 45 years old, you begin to notice daytime sleepiness. OSA is finally diagnosed on the later 50 or even later.
How is it diagnosed?
The polygraph study of nocturnal sleep is the best test for the diagnosis of sleep apnea. Through it, it is registered, for a whole night, a number of functions during sleep, such as the electrical activity of the brain, eye movements, muscle activity, electrocardiogram, the effort of the respiratory muscles, nasal and oral breathing and the oxygen level in the blood.
Polygraphic sleep studies are usually performed in specialized centers where the patient stays the night; its implementation implies an important technical differentiation.
It is now possible to make certain simplified studies at home with the patient handsets. Strictly speaking, these tests can not be considered sleep studies and give limited information.
What is the best treatment?
The therapy depends on the clinical characteristics of each individual and the results of the sleep study.
Avoid alcohol, tobacco and hypnotics, loss of weight and try not to sleep on his back, are part of the therapeutic program.
The most effective therapy is the ventiloterapia with continuous positive pressure in the nasal mask. It is one of the mechanical treatment in which the patient sleeps with a mask over the nose through which the air under pressure is forced to enter through the nostrils. The air pressure is generated by a simple apparatus, and is adjusted in order to be sufficient to prevent airway collapse. This treatment prevents apneas and allows a continuous and relaxed sleep. Its prescription requires a polygraph study of prior sleep.
In certain cases of mild OSA or snoring, dental arches can be the most effective solution. This device generally prepared by dentists, allow the repositioning of the lower jaw and tongue.
The ENT surgery may be useful in some well-selected cases. Its aim is to increase the diameter of the airway. There are several procedures, from removing tonsils and adenoids, polyps or other causes of obstruction, to the correction of structural deformities. The UPPP (UPPP) is the removal of excess soft tissue in the back of the oropharynx (tonsils, uvula, and soft palate part).
The uvulopalatoplasty laser (LAUP) or radio frequency energy (RFUP) is used especially in the treatment of snoring, but does not eliminate sleep apnea.
Whenever there is indication for surgical procedure, it should be done previously a polygraph study of sleep. The purpose of this study is to detect a possible apnea before the surgery eliminates the main symptom "label" of the OSA, the snore.
Some maxillofacial surgical procedures may be indicated when there are lower jaw deformities.