Sleep-Disordered Breathing (SDB)

Snoring and Sleep Apnea are common terms that help to describe parts of the continuum of sleep-disordered breathing. This spectrum ranges from slight vibration of tissues at its mildest to death from asphyxiation at its severe extreme. Between these two lay (pathologic) snoring, partial closure (hypopnea) or complete closure (apnea) of the airway resulting in increased airway resistance or complete and partial cessation of breathing.

The long-term effects of such disturbed breathing dramatically increase the risk of (among others) stroke, hypertension, arteriosclerosis, myocardial infarction, cardiac arrhythmias, pulmonary hypertension, congestive heart failure, depression, heart- burn and diabetes. Recent research and publications suggest that there are several other medical conditions associated with Sleep-Disordered Breathing.

Sleep-Disordered Breathing also disrupts the normal patterns of brain activity and relaxation preventing achievement of restorative sleep. Excessive daytime sleepiness contributes to the risk of accident and injury from decreased attention span, judgment, and reflex. The risk of automobile accident in the untreated sleep apneic patient is about 7 times that of a normal sleeper. This very comparable to impaired driving caused by alcohol misuse. Work productivity and safety suffer, not to mention the decrease of quality of life.

What causes Sleep-Disordered Breathing?

During the increasing muscular relaxation of deepening sleep, the airway can become very flaccid. The relaxation of the tongue can cause it to fall back, touching the back of the throat, which either partially or completely closes the airway. This is Obstructive Sleep Apnea (OSA).

Snoring is vibration of the uvula, soft palate, and throat walls against the tongue resulting in reduced airflow. In the apneic patient, the snoring can stop for between 10 seconds and two minutes. During this silent period, the patient is unable to breathe. When the body "realizes" it is suffocating due to this restricted or closed airway, adrenaline is secreted to raise blood pressure, arouse the sleeper to a less deep level of sleep, and cause body movements in an attempt to restart or improve breathing. In the severe Sleep Apnea patient, this process may be repeated 300-400 times per night, resulting in severe disruptions of normal sleep and brain wave activity. The ultimate result is sleep fragmentation and deprivation and all the dangerous side effects of that condition.

How is sleep-disordered breathing diagnosed?

According to the American Academy of Sleep Medicine (AASM) and the Academy of Dental Sleep Medicine (ADSM) the gold standard for diagnosis of Sleep-Disordered Breathing is overnight sleep testing. The test is called overnight polysomnography (PSG). This test is done in special facilities where the patient will stay overnight. The patient will then be hooked up by a sleep technician to a polysomnograph machine; this machine records (among others) your breathing, heartrate, oxygen blood saturation, limb movements and brainwaves during your sleep.A Sleep specialist will then review the records and make a diagnosis.  An alternate method is to do a home sleep study; this study is limited in channels and is sometimes used for screening purposes. Some Sleep Centers requires a limited overnight home study before they accept the patient for the more expensive in-lab full overnight polysomnography.

 

Treatment options for Sleep-Disordered Breathing (SDB)

Depending on the diagnosis (pathologic snoring, upper airway resistance syndrome, mild, moderate or severe sleep apnea) and other clinical findings there are several options for treatment modalities. The most common advice is weight loss and increased physical fitness; obesity is highly associated with SDB. Secondly changing sleep position; some patients show a remarkably decrease of snoring and apneic events when they are sleeping on their side instead of their back. The gold standard of treatment options is the use of CPAP (Continuous Positive Airway Pressure); this is a device that blows air into the airway through a mask, maintaining patency of the airway allowing the patient to breathe. When the diagnosis is moderate to severe sleep apnea, the AASM and ADSM recommends the use of CPAP.  In case the diagnosis is mild to moderate Sleep Apnea, there are options in the treatment modalities; some will benefit from CPAP and others will be able to use an oral appliance.This will be determined by the treatment team, consisting of a trained dentist and a sleep specialist.If the diagnosis is mild Sleep Apnea, upper airway resistance syndrome (UARS) or pathologic snoring, then oral appliances are indicated; however the dental condition of patient must meet some minimum requirement. There are many designs of oral appliances and it is the task of the trained dentist to choose the most appropriate design for the patient. Last option of treatment is surgery; this can vary from removal of tonsils and / or adenoid to jaw surgery. A team consisting of a trained dentist and a medical specialist (ENT, Respirologist, and Oral Surgeon) will determine what the best option is for the patient.