Sleep apnea

Sleep apnea
Specialty	Pulmonology, otorhinolaryngology

Sleep apnea
Specialty	Pulmonology, otorhinolaryngology

Sleep apnea (alternatively sleep apnoea) is a sleep disorder characterized by brief interruptions of breathing during sleep. These episodes, called apneas (literally, "without breath"), each last long enough so one or more breaths are missed. The episodes occur repeatedly throughout sleep. There are two forms of sleep apnea: Central and Obstructive. Breathing is interrupted by the lack of effort in Central Sleep Apnea, but from a physical block to airflow despite all efforts in Obstructive Sleep Apnea. (There are also mixed forms of apnea, discussed in the detailed section on Obstructive Sleep Apnea below). Regardless of type, the affected individual with sleep apnea is rarely (if ever) aware of having difficulty breathing, even upon awakening. Sleep apnea is recognized as a problem by others witnessing the individual during episodes, or is suspected because of its effects on the body (sequelae).The definitive diagnosis of sleep apnea is made by polysomnography.

Central Sleep Apnea

In pure Central Sleep Apnea, the brain's control centers "forget" to breathe during sleep. The clinical picture of a sleeping individual with Central Sleep Apnea is of someone asleep who stops breathing, and then starts again. There is no effort made to breathe during the pause in breathing, no chest movements, no struggling to get air, just stillness. After the episode of apnea, breathing may be faster for a period of time.

Breathing is regular in a healthy person at rest, and oxygen levels and carbon dioxide levels in the bloodstream stay fairly constant. That's because a sudden drop in oxygen or excess of carbon dioxide strongly stimulates the brain's respiratory centers to breathe. In apnea, those basic controls are not working correctly. If the pause in breathing is long enough, the percentage of oxygen in the circulation will drop to a lower than normal level (hypoxia) and the concentration of carbon dioxide will build to a higher than normal level (hypercapnia). In turn, these conditions will trigger additional effects on the body. Since brain cells need oxygen to live, if the level of blood oxygen goes low enough for long enough, the terrible consequences of brain damage, and death can occur. Fortunately, Central Sleep Apnea is more often a chronic condition that causes much milder effects than sudden death. The exact effects of the condition will depend on how severe the apnea is, and the individual characteristics of the person having the apnea. Several examples are discussed below, and more about the nature of the condition is presented in the section on Clinical Details.

In any person, hypoxia and hypercapnea have certain common effects on the body. The heart rate will increase, unless there are severe co-existing problems with the heart or autonomic nervous sytem that make this impossible. The more translucent areas of the body will show a bluish or dusky cast from cyanosis, which is the change in hue that occurs with a massive build-up of carbon dioxide. Overdoses of drugs that are respiratory depressants (such as heroin and other opiates) kill by dampening the activity of the brain's respiratory control centers. In Central Sleep Apnea, the effects of sleep alone can remove the brains' mandate for the body to breathe. Fortunately, even in severe cases of central sleep apnea, the effects almost always result in pauses that make breathing irregular, rather than the total cessation of breathing.

• Normal Respiratory Drive: After exhalation, the blood level of oxygen decreases and that of carbon dioxide increases. Exchange of gasses with a lungful of fresh air is necessary to replenish oxygen and rid the bloodstream of built-up carbon dioxide. How do the changing blood levels of oxygen and carbon dioxide result in a breath? In any healthy animal, including humans, oxygen and carbon dioxide receptors in the blood stream (called chemoreceptors) send nerve impulses to the brain, which then signals reflex opening of the larynx (so that the opening between the vocal cords enlarges) and movements of the rib cage muscles and diaphragm. These muscles expand the thorax (chest cavity) so that a partial vacumn is made within the lungs and air rushes in to fill it. The body inhales.
• Physiologic effects of Central Apnea: During central apneas, the central respiratory drive is absent, and the brain does not respond to changing blood levels of the respiratory gasses. No breath is taken despite the normal signals to inhale. The immediate effects of Central Sleep apnea on the body depend on how long the failure to breathe endures. At worst, central sleep apnea may cause sudden death. Short of death, drops in blood oxygen may trigger seizures- even in the absence of epilepsy. In people with epilepsy, the hypoxia caused by apnea may trigger seizures that had previously been well controlled by medications. In other words, a seizure disorder may become unstable in the presence of sleep apnea. In adults with coronary artery disease, a severe drop in blood oxygen level can cause angina, arrythmias, or heart attacks (myocardial infarction).With longstanding recurrent episodes of apnea, increases in carbon dioxide levels may change the pH of the blood enough to cause a metabolic acidosis.

Sleep Laboratory Findings in Central Sleep Apnea

Polysomnography in central sleep apnea shows pauses in breathing that are followed by drops in blood oxygen and increases in blood carbon dioxide. In adults, a pause must last 10 seconds to be scored as an apnea. However in young children, who normally breathe at a much faster rate than adults, the pause may be many seconds shorter and still be considered apnea. The cessation of airflow in central sleep apnea is not associated with chest movements. Airflow ceases at the nose and lips, and the chest remains still.

Clinical Details: Who gets Central Sleep Apnea? What happens to them?

Any individual, no matter how healthy, who is given enough of a central respiratory depressant drug may develop apnea on a central basis. Generally, drugs that are central respiratory depressants also have sedative actions, and so the individual taking a toxic dose of such a drug is likely to be asleep, or at least in an altered state of conciousness, when breathing becomes irregular. Alcohol is such a central respiratory depressant in large doses, so are opiates, barbituartes and many tranquilizers.

Premature infants with immature brains and reflex systems are at high risk for central sleep apnea syndrome, even if otherwise healthy. Fortunately, even those premature babies who have the syndrome will generally outgrow it as they mature, providing they receive careful enough monitoring and supportive care during infancy to survive.

Sudden Infant Death Syndrome (SIDS), a tragedy in which an apparently healthy baby dies in sleep, is sometimes caused by central sleep apnea. There are probably many causes of SIDS, however, and central apnea is only one of them.

Congenital Hypoventilation Syndrome: This rare, inborn condition involves a specific defect in the respiratory centers of the Central Nervous System. Congenital Hypoventilation ("Abnormally low"-" ventilation") Syndrome is treatable. The children who have it must have tracheotomies and access to mechanical ventilation on respirators while sleeping, but generally are free of the need to be attached to a respirator while awake. This form of sleep apnea has been called Ondine's curse.

Adults suffering from Congestive Heart Failure are at risk for a form of Central Sleep Apnea called Cheyne Stokes Respiration. This is periodic breathing with recurrent episodes of apnea alternating with rapid breathing. In those who have it, Cheyne Stokes Respirations occurs while both awake and asleep. There is good evidence that replacement of the failed heart cures central apnea in these patients.

A person who has some form of sleep apnea, including obstructive sleep apnea, is more likely to have dangerous levels of central sleep apnea if a drug that is a central respiratory depressant is taken. Should these individuals have general anesthesia, for example, they require prolonged montitoring after initial recovery, as compared to a perswon with no history of sleep apnea, because of the risk that apnea will be more severe with even low levels of the drugs in the system. Additionally, the use of a tranquilizer, alcohol or opiate dose which might be quite safe in a similar person without sleep apnea may cause breathing to stop in a person with sleep apnea.

References

1) Macey PM. Macey KE. Woo MA. Keens TG. Harper RM. Aberrant neural responses to cold pressor challenges in congenital central hypoventilation syndrome.[see comment]. [Journal Article] Pediatric Research. 57(4):500-9, 2005 Apr. 2)Bradley TD. Floras JS. Sleep apnea and heart failure: Part II: central sleep apnea. [Review] [55 refs] [Journal Article. Review] Circulation. 107(13):1822-6, 2003 Apr 8. 3) Mansfield DR. Solin P. Roebuck T. Bergin P. Kaye DM. Naughton MT. The effect of successful heart transplant treatment of heart failure on central sleep apnea.[see comment]. [Journal Article] Chest. 124(5):1675-81, 2003 Nov.

Obstructive Sleep Apnea

Obstructive sleep apnea is not only much more common than central apnea, it occurs fairly frequently. If studied carefully in a sleep lab by polysomnography, approximately 1 in 5 American adults has at least mild OSA. Shamsuzzaman AS, Gersh BJ, Somers VK. Obstructive sleep apnea: implications for cardiac and vascular disease. JAMA. 2003;290:1906–1914. Since the muscle tone of the body ordinarily relaxes during sleep, and since,at the level of the throat, the human airway is composed of walls of soft tissue, which can collapse, it is easy to understand why breathing can be obstructed during sleep - particularly in the obese. Although many individuals experience episodes of obtructive sleep apnea at some point in life, a much smaller percentage of people are afflicted with chronic severe obstructive sleep apnea.

Normal sleep has different stages which range from light to deep. The deeper stages are required for the restorative effects of sleep, but are also the stages during which the muscle tone of the throat and neck is most reduced. If the airway collapses in deep sleep when muscles relax, either arousal to a lighter stage of sleep or awakening occurs. In severe cases of obstructive sleep apnea, very little time is spent in deep sleep and the result is sleep deprivation, no matter how many hours are spent sleeping in the lighter stages.

Many people experience obstructive sleep apnea for only a short period of time. This can be the result of an upper respiratory infection that causes nasal obstruction, along with swelling of the throat, or tonsillitis that temporarily produces very enlarged tonsils. The Epstein-Barr virus, for example, is known to be able to dramatically increase the size of lymphoid tissue during acute infection, and obstructive sleep apnea is fairly common in acute cases of severe infectious mononucleosis.

Sleep Laboratory Findings in Obstructive Sleep Apnea

Results of polysomnography in obstructive sleep apnea show pauses in breathing that may be followed by a decrease in blood oxygen (hypoxia) and an increase in the blood carbon dioxide (hypercapnia). Monitors for airflow at the nose and mouth with show cessation of airflow, but efforts to breathe are not only present, they are often exagerated. The chest muscles contract and the entire body may thrash and struggle, much as if an imaginary pillow was being used to suffocate the sleeper.

Who gets Obstructive Sleep Apnea? Populations at Risk

Individuals with decreased muscle tone, increased soft tissue around the airway, and structural features that give rise to a narrowed airway are at high risk for obstructive sleep apnea.

In adults, the most typical individual with obstructive sleep apnea syndrome is obese, with particular heaviness at the face and neck. The cartoon image of bearded Bluto, as compared to the thin necked cartoon companions, is an illustration of such a body type. In the filmed cartoons, Bluto actually did snore heavily with pauses in breathing! File:Popeye-floor-flusher.jpg

The hallmark symptom of obstructive sleep apnea syndrome in adults is excessive daytime sleepiness. Typically, an adult or adolescent with severe long-standing obstructive sleep apnea will fall asleep for very brief periods in the course of usual daytime activities -if given any opportunity to sit or rest. This behavior may be quite dramatic, sometimes occuring during conversations with others at social gatherings. Although this so called "hyper-somnolence" (excessive sleepiness) may also occur in children, it is not at all typical of younger children with sleep apnea. Toddlers and young children with severe obstructive sleep apnea instead ordinarily behave as if "over-tired" or "hyper". Adults and children with very severe obstructive sleep apnea also differ in typical body habitus. Adults are generally heavy, with particularly short and heavy necks. Young children, on the other hand, are generally not only thin but may have "failure to thrive", where growth is reduced. Poor growth occurs for two reasons: the work of breathing is high enough so that calories are burned at high rates even at rest, and the nose and throat are so obstructed that eating is both tasteless and physically uncomfortable. Obstructive sleep apnea in children, unlike adults, is almost always caused by obstructive tonsils and adenoids and is usually cured with tonsillectomy and adenoidectomy.

Additional signs of obstructive sleep apnea include restless sleep, and loud snoring (with periods of silence followed by gasps). Other symptoms are non-specific: morning headaches, trouble concentrating, irritability, forgetfulness, mood or behavior changes, weight gain, increased heart rate, anxiety, depression, increased frequency of urination, bedwetting, esophageal reflux and heavy sweating at night. Obstructive Sleep Apnea is somewhat more likely to occur in men than in women, and in people who are overweight or obese.

The most serious consequence of obstructive sleep apnea is to the heart. In severe and prolonged cases, there are increases in pulmonary presures that are transmitted to the right side of the heart. This can result in a severe form of congestive heart failure (cor pulmonale).

Obstructive Sleep Apnea occurs more frequently in people with Down Syndrome than in the general population. A little over 50% of all people with Down Syndrome suffer from sleep apnea (de Miguel-Díez, et al 2003), and some advocate routine testing of this group (Shott, et al 2006).

Mixed Apnea

Some people with sleep apnea have a combination of both types. When obstructive sleep apnea syndrome is severe and longstanding, episodes of central apnea commonly develop.

History

The first reports of what is now called obstructive sleep apnea in the medical literature date only from 1965, when it was independently described by French and German investigators. However, the clinical picture of this condition has long been recognized as a character trait, without an understanding of the disease process. The term “Pickwickian syndrome”,that is sometimes used for the syndrome came from Charles Dickens' description of Joe, "the fat boy" in his novel, The Pickwick Papers.

The early reports of sleep apnea described individuals who were very severely affected, often presenting with severe hypoxemia, hypercapnia and congestive heart failure. Tracheostomy was the recommended treatment and, though it could be life-saving, post-operative complications in the stoma were frequent in these very obese and short-necked individuals.

The management of obstructive sleep apnea was revolutionized with the introduction of continuous positive airway pressure (CPAP), first described in 1981 by Colin Sullivan and associates in Sydney, Australia. The first models were bulky and noisy but the design was rapidly improved and by the late 1980s CPAP was widely adopted. The availability of an effective treatment stimulated an aggressive search for affected individuals and led to the establishment of hundreds of specialized clinics dedicated to the diagnosis and treatment of sleep disorders. Though many types of sleep problems are recognized, the vast majority of patients attending these centers have sleep disordered breathing.

Obstructive sleep apnea (OSA)

File:Apnea2Min.jpg

Two minute epoch representing continuous OSA. Click on this image for larger version.

Recurrent airway obstruction gives rise to the obstructive sleep apnea (OSA) syndrome, the most common category of sleep-disordered breathing, with 2% of female and 4% of male subjects meeting the minimal diagnostic criteria for OSA of at least 10 apneic events per hour. An "event" can be either an apnea, characterised by complete cessation of airflow for at least 10 seconds, or a hypopnea in which airflow decreases by 50 percent for 10 seconds or decreases by 30 percent if there is an associated decrease in the oxygen saturation or an arousal from sleep (American Academy of Sleep Medicine Task Force, 1999). To grade the severity of sleep apnea the number of events per hour is reported as the apnea-hypopnea index (AHI). An AHI of less than 5 is considered normal. An AHI of 5-15 is mild; 15-30 is moderate and more than 30 events per hour characterizes severe sleep apnea.

Diagnosis

Almost everybody who has obstructive sleep apnea is a snorer, often a very heavy snorer. Pauses in breathing during sleep are commonly noticed by a bed partner but this history is often lacking and up to five "events" per hour are considered normal. One of the more consistent symptoms is "nonrestorative sleep," meaning that the patient wakes in the morning feeling unrefreshed no matter how much he slept during the night. Excessive daytime sleepiness is common in sleep apnea of any severity, but some patients complain of fatigue rather than sleepiness and others notice neither. Other symptoms include hypertension, anxiety/depression, trouble concentrating, and nocturnal awakenings.

The most accurate diagnostic tool, polysomnography, can establish the diagnosis and assist in identifying the type of sleep apnea present. This test is usually done overnight in specialized sleep laboratories, either freestanding or in a hospital. Portable sleep recording systems that can perform unattended polysomnography in the patient's home or hospital bed are used in certain circumstances, but in-laboratory testing with a technician present remains the gold standard and is required by many insurers, (eg. Medicare of the United States) before they will pay for treatment of the condition.

Screening devices, measuring fewer parameters than traditional polysomnography, are sometimes used to determine if patients are likely to test positive for obstructive sleep apnea. The value of such devices is the subject of debate and study among sleep medicine professionals. Some feel that such devices can reduce costs and conserve resources, while others feel that the devices are unnecessary: a positive result leads to polysomnography anyway, while a negative result cannot be trusted if the patient still complains of symptoms.

Treatment

There are a variety of treatments for sleep apnea, depending on an individual’s medical history, the severity of the disorder and the specific cause of the obstruction.

In acute infectious mononucleosis, for example, although the airway may be severely obstructed in the first 2 weeks of the illness, the presence of the tissue (suddenly enlarged tonsils and adenoids) blocking the throat is most likely only temporary. A course of anti-inflammatory steroids such as prednisone (or another kind of glucocorticoid drug) is often given to reduce this lymphoid tissue. Although the effects of the steroids are only temporary, in most affected individuals, so is the tonsillar and adenoidal enlargement. In unusual cases where the enlarged lymphoid tissue persists after resolution of the infection, or in which medical treatment does not adequately relieve the obstruction, tonsillectomy and adenoidectomy may be required.

The treatment for obstructive sleep apnea in the case of adults with poor oropharyngeal airways secondary to body type is varied.

Some treatments involve lifestyle changes, such as avoiding alcohol and medications that relax the central nervous system (for example, sedatives and muscle relaxants), losing weight, and quitting smoking. Some people are helped by special pillows or devices that keep them from sleeping on their backs, or oral appliances to keep the airway open during sleep. If these conservative methods are inadequate, doctors often recommend continuous positive airway pressure (CPAP), in which a face mask is attached to a tube and a machine that blows pressurized air into the mask and through the airway to keep it open. There are also surgical procedures that can be used to remove tissue and widen the airway, but the success rate is not high. Some individuals may need a combination of therapies to successfully treat their sleep apnea.

Physical intervention

The most widely used current therapeutic intervention is positive airway pressure whereby a breathing machine pumps a controlled stream of air through a mask worn over the nose, mouth, or both. The additional pressure splints or holds open the relaxed muscles, just as air in a balloon inflates it. There are several variants:

• (CPAP), or Continuous Positive Airway Pressure, in which a controlled air compressor generates an airstream at a constant pressure. This pressure is prescribed by the patient's physician, based on an overnight test or titration. Newer CPAP models are available which slightly reduce pressure upon exhalation to increase patient comfort and compliance. CPAP is the most common treatment for obstructive sleep apnea.
• (VPAP), or Variable Positive Airway Pressure, also known as bilevel or BiPAP, uses an electronic circuit to monitor the patient's breathing, and provides two different pressures, a higher one during inhalation and a lower pressure during exhalation. This system is more expensive, and is sometimes used with patients who have other coexisting respiratory problems and/or who find breathing out against an increased pressure to be uncomfortable or disruptive to their sleep.
• (APAP), or Automatic Positive Airway Pressure, is the newest form of such treatment. An APAP machine incorporates pressure sensors and a computer which continuously monitors the patient's breathing performance. It adjusts pressure continuously, increasing it when the user is attempting to breathe but cannot, and decreasing it when the pressure is higher than necessary. Although FDA approved, these devices are still considered experimental by many and are not covered by most insurances.

A second type of physical intervention, a Mandibular advancement splint (MAS), is sometimes prescribed for mild or moderate sleep apnea sufferers. The device is a mouthguard similar to those used in sports to protect the teeth. For apnea patients, it is designed to hold the lower jaw slightly down and forward relative to the natural, relaxed position. This position holds the tongue farther away from the back of the airway, and may be enough to relieve apnea or improve breathing for some patients.

The FDA accepts only 16 oral devices for the treatment of sleep apnea. A listing is available at their website

Oral appliance therapy is less effective than CPAP, but is more 'user friendly'. Side-effects are common but rarely is the patient aware of them.

Medical (pharmaceutical) treatment

Few drug-based treatments of obstructive sleep apnea are known despite over two decades of research and tests.

Oral administration of the methylxanthine theophylline (chemically similar to caffeine) can reduce the number of episodes of apnea, but can also produce side effects such as palpitations and insomnia. Theophylline is generally ineffective in adults with OSA, but is sometimes used to treat Central Sleep Apnea (see below), and infants and children with apnea.

When other treatments do not completely treat the OSA, drugs are sometimes prescribed to treat a patient's daytime sleepiness or somnolence. These range from stimulants such as amphetamines to modern anti-narcoleptic medicines. The anti-narcoleptic modafinil is seeing increased use in this role as of 2004.

In some cases, weight loss will reduce the number and severity of apnea episodes, but for most patients excessive weight is an aggravating factor rather than the cause of OSA. In the morbidly obese, a major loss of weight (such as what occurs after bariatric surgery) can sometimes cure the condition.

Neurostimulation

Many researchers believe that OSA is at root a neurological condition, in which nerves that control the tongue and soft palate fail to sufficiently stimulate those muscles, leading to over-relaxation and airway blockage. A few experiments and trial studies have explored the use of pacemakers and similar devices, programmed to detect breathing effort and deliver gentle electrical stimulation to the muscles of the tongue.

This is not a common mode of treatment for OSA patients as of 2004, but it is an active field of research.

Surgical intervention

A number of different surgeries are often tried to improve the size or tone of the patient's airway. For decades, tracheostomy was the only effective treatment for sleep apnea. It is used today only in very rare, intractable cases that have withstood other attempts at treatment. Modern treatments try one or more of several options, tailored to the patient's needs. Often the long term success rate is low, prompting many doctors to favour CPAP as the gold standard.

• Nasal surgery, including turbinectomy (removal or reduction of a nasal turbinate), or straightening of the nasal septum, in patients with nasal obstruction or congestion which reduces airway pressure and complicates OSA.
• Tonsilectomy and/or adenoidectomy in an attempt to increase the size of the airway.
• Removal or reduction of parts of the soft palate and some or all of the uvula, such as uvulopalatopharyngoplasty (UPPP) or laser-assisted uvulopalatoplasty (LAUP). Modern variants of this procedure sometimes use radiofrequency waves to heat and remove tissue.
• Reduction of the tongue base, either with laser excision or radiofrequency ablation.
• Genioglossus Advancement, in which a small portion of the lower jaw which attaches to the tongue is moved forward, to pull the tongue away from the back of the airway.
• Hyoid Suspension, in which the hyoid bone in the neck, another attachment point for tongue muscles, is pulled forward in front of the larynx.
• Maxillomandibular advancement (MMA). A more invasive surgery usually only tried in difficult cases where other surgeries have not relieved the patient's OSA, or where an abnormal facial structure is suspected as a root cause. In MMA, the patient's upper and lower jaw are detached from the skull, moved forward, and reattached with pins and/or plates.
• Pillar procedure, three small inserts are injected into the soft palate to offer support, potentially reducing snoring and mild to moderate sleep apnea[1].

Obstructive sleep apnea and craniofacial malformations

Even though OSA is not uncommon to the general population, it is much more often found in patients with craniofacial anomalies and repaired cleft palate. More often than not this patient population consists mainly of children, but adults can still acquire OSA after a surgery to improve velopharyngeal insufficiency (VPI). The diagnosis of OSA is based upon clinical observation (including extensive case history) as well as objective diagnostic measures. Bell & Turvey (2001) emphasize that an accurate diagnosis including place of obstruction is best determined through detailed history taking, clinical evaluation, and evaluation of the upper airway and skeletal relationships with endoscopy, plain radiography, computed tomography, and polysomnography when indicated. Other possible measures include magnetic resonance imaging and bronchoscopy. Since OSA is a multifaceted disorder spread across all populations, it is often necessary for the patient to undergo most if not all of the above diagnostic measures. Because of the complex anatomy and physiology of children and adults with craniofacial anomalies and/or cleft palate, the previous list is often required in its entirety.

The normally structured airway receives contributions from hard and soft tissue anatomy, centrally and peripherally mediated neuromuscular factors, and sleep-associated muscular relaxation (Bell & Turvey, 2001). Obstructive sleep apnea occurring in patients with craniofacial anomalies is due to an obstruction in the upper airway caused by some abnormal structure and/or function. The location of obstruction may vary in size and significance and also depend on head position, respiratory phase variation, and stage of sleep (Shepard & Thawley, 1990). Many of these patients can be medically fragile but unless there is an associated neurologic dysfunction, the child is less likely to present with a central or peripheral neuromuscular cause of the sleep apnea. The most common neuromuscular factor that contributes to OSA is an alteration in muscle tone caused by generalized hypotonia (e.g., Prader-Willi syndrome) or hypertonia (Sher, 1990).

Various craniofacial disorders resulting in midface deformities (i.e., bilateral maxillary hypoplasia and/or bilateral mandibular hypoplasia) include but are not limited to: Pierre Robin sequence, Crouzon syndrome, Treacher Collins syndrome, Cerebrocostomandibular syndrome, CHARGE association, and various episodes of craniofacial synostosis (e.g., Apert’s syndrome). Maxillomandibular hypoplasia often results in a reduction of the dimensions of the oropharyngeal airspace (e.g., glossoptosis as seen in mandibular hypoplasia) and gives rise to significant breathing difficulties while awake and more often during sleep. While asleep the pharyngeal musculature relaxes and partially collapses upon itself. Combined with a predisposed narrow pharyngeal airspace, breathing difficulties are apt to arise. Patients with Down syndrome often have some amount of obstruction of the oral cavity due to macroglossia which can become quite severe in some cases. Contributions to obstruction in the nasal airway include choanal atresia, septal deviation, and pyriform aperture stenosis. Shortening of the anterior cranial base and an acute cranial base angle is known to narrow the nasopharynx and oropharynx in all dimensions (Cohen & Kreiborg, 1992). According to Perkins et al. (1997), the combination of nasal airway compromise, skull-base involvement, narrowing of the nasopharynx and oropharynx, and tracheal abnormalities (e.g., fused tracheal rings, laryngeal/tracheal malacia) puts these patients at significant risk for airway obstruction. Another common risk factor for OSA in all children includes adenotonsillar hypertrophy which, combined with midface hypoplasia and a narrow pharyngeal airspace, predisposes the child to significant breathing problems.

Treatment for OSA in Craniofacial Malformations

Treatments for OSA resultant from craniofacial anomalies are widely variable and are dependent on the site and severity of obstruction, as well as the patient’s other pre-morbid conditions. Initial non-surgical interventions for mild-to-moderate obstruction include positioning therapy and a nasopharyngeal or oral airway while severe obstruction typically requires endotracheal intubation and some patients will require further intervention including: topical vasoconstrictive therapy, choanal atresia repair, glossopexy, hyoid suspension, tonsillectomy and/or adenoidectomy, and tracheotomy (Perkins et al., 1997).

Skeletal advancement in an effort to physically increase the pharyngeal airspace is often an option for this population. The authors caution that even though skeletal advancement is not contraindicated in the presence of distal obstructions, clinical improvement may not be expected by skeletal advancement alone. Also, accurate diagnosis is fundamental to the success or failure of any intervention, be it surgical or therapeutic. Another conclusion made by the authors is that the method of skeletal advancement may not be significant to the outcome, but in order to obtain a better success rate, skeletal expansion should be accompanied by some form of soft tissue reduction at the site of obstruction.

Public Examples

Here's a list of notable people and fictional characters afflicted with sleep apnea.

• Jerry Garcia
• Glen Milstead (Divine)
• Anne Rice
• Junior Soprano (Corrado, AKA Uncle June)
• William Howard Taft
• Johnny Grunge
• William Tarmey (Jack Duckworth, Coronation Street)

References

• American Academy of Sleep Medicine Task Force (1999). "Sleep-related breathing disorders in adults: recommendations for syndrome definition and measurement techniques in clinical research". Sleep. 22 (5): 667–89. PMID 10450601.
  • Bell, R. B., & Turvey, T. A. (2001). Skeletal advancement for the treatment of

obstructive sleep apnea in children. Cleft Palate-Craniofacial Journal, 38(2), 147-54.

• Caples S, Gami A, Somers V (2005). "Obstructive sleep apnea". Ann Intern Med. 142 (3): 187–97. PMID 15684207.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Cohen, M. M. J., & Kreiborg, S. (1992). Upper and lower airway compromise in the

Apert syndrome. American Journal of Medical Genetics, 44, 90-93.

• de Miguel-Díez J, Villa-Asensi J, Alvarez-Sala J (2003). "Prevalence of sleep-disordered breathing in children with Down syndrome: polygraphic findings in 108 children" (PDF). Sleep. 26 (8): 1006–9. PMID 14746382.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Mathur R, Douglas N (1994). "Relation between sudden infant death syndrome and adult sleep apnoea/hypopnoea syndrome". Lancet. 344 (8925): 819–20. PMID 7916096.
• Mortimore I, Douglas N (1997). "Palatal muscle EMG response to negative pressure in awake sleep apneic and control subjects". Am J Respir Crit Care Med. 156 (3 Pt 1): 867–73. PMID 9310006.
• Perkins, J. A., Sie, K. C. Y., Milczuk, H., & Richardson, M. A. (1997). Airway

management in children with craniofacial anomalies. Cleft Palate-Craniofacial Journal, 34(2), 135-40.

• Sculerati N. Gottlieb MD. Zimbler MS. Chibbaro PD. McCarthy JG. Airway management in children with major craniofacial anomalies. [Journal Article] Laryngoscope. 108(12):1806-12, 1998 Dec.
• Shepard, J. W., & Thawley, S. E. (1990). Localization of upper airway collapse during sleep in patients with obstructive sleep apnea. American Review of Respiratory Disorders, 141, 1350-55.
• Sher, A. (1990). Obstructive sleep apnea syndrome: a complex disorder of the upper airway. Otolaryngologic Clinics of North America, 24, 600.
• Shott S, Amin R, Chini B, Heubi C, Hotze S, Akers R (2006). "Obstructive sleep apnea: Should all children with Down syndrome be tested?". Arch Otolaryngol Head Neck Surg. 132 (4): 432–6. PMID 16618913.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Slovis B. & Brigham K. (2001). "Disordered Breathing". In ed Andreoli T. E. (ed.). Cecil Essentials of Medicine. Philadelphia: W.B. Saunders. pp. pp210-211. {{cite book}}: |pages= has extra text (help)
• Strollo P, Rogers R (1996). "Obstructive sleep apnea". N Engl J Med. 334 (2): 99–104. PMID 8531966.
• Sullivan C, Issa F, Berthon-Jones M, Eves L (1981). "Reversal of obstructive sleep apnoea by continuous positive airway pressure applied through the nares". Lancet. 1 (8225): 862–5. PMID 6112294.{{cite journal}}: CS1 maint: multiple names: authors list (link)

See also

• Hypopnea
• Sleep
• Polysomnography

External links

• SleepApneaInfo and "Sleep Well, Be Healthy" campaign
• American Sleep Apnea Association
• The National Sleep Foundation "Sleeptionary" entry on sleep apnea
• Alertness Matters: Sleep apnea symptoms, related sleep disorders and treatment
• LeadingpProvider authoritative information, resources and support on Sleep Apnea
• Australian Snoring and Sleep Apnoea Discussion Forum
• Sleep Apnea: Symptoms, Causes, Diagnosis, and Treatment
• All about Obstructive Sleep Apnea and Polysomnogram Test
• Li K, Riley R, Powell N, Guilleminault C (2000). "Maxillomandibular advancement for persistent obstructive sleep apnea after phase I surgery in patients without maxillomandibular deficiency". Laryngoscope. 110 (10 Pt 1): 1684–8. PMID 11037825.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• Sleep apnea self-assessment quiz
• Lungs Online - Sleep Apnea
• Clinical and Alternative Treatment Options for Sleep Apnea
• A worldwide listing of doctors certified by the American Board of Sleep Medicine
• Awake In America a national non-profit (U.S.) organization focused on sleep and sleep disorders, with the primary focus of helping establish community education and support groups throughout the United States.
• Apnea Board - an open, non-profit discussion forum devoted exclusively to Sleep Apnea patients
• Sleep Apnea Treatment
• Sleep Apnea in Down Syndrome
• Talk About Sleep: Authoratative sleep apnea information