Snoring and Obstructive Sleep Apnea
These terms 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 lies pathologic snoring and periods of complete closure of the airway called “apnea”.
The long-term effects of such disturbed breathing dramatically increases the risk of stroke, hypertension (high blood pressure), arteriosclerosis (hardening of the arteries), myocardial infarction (heart attack), cardiac arrhythmias (irregular pulse),Type II diabetes and others.
Sleep disordered breathing also disrupts the normal patterns of brain activity and relaxation, precluding restorative sleep. Overwhelming 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 is about 7 times that of a normal sleeper. Work productivity and safety suffer.
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. The snoring is primarily an inspiratory vibration of the uvula, soft palate, tonsils and throat walls against the tongue with reduced airflow, or a complete closure of the airway resulting in periods of silence. As the saturation of the oxy-hemoglobin of the blood decreases when the airway closes (apnea) or narrows significantly (hypopnea), the chemo- and baro-receptors in the carotid bodies, in response to hypoxemia or hypercapnia, induce the pituitary to engage the sympathetic nervous system.
Adrenaline and hormones are secreted. The result is an immediate rise in blood pressure and pulse rate, increase in insulin resistance and increase in brain activity. The sympathetic nervous system engages to ultimately increase the voluntary muscle tone of the pharynx. Once the airway patency is restored the brain again attempts to achieve sleep. The cycle repeats inducing damaging instability of the cardio-vascular system over time. More than 5 apnea or hypopnea events per hour is considered abnormal. Above 30 times per hour is considered severe OSA but it is common to see much more severe scoring up to and over 100.
Beyond all of the pathophysiologic damage, the ultimate result includes sleep deprivation and all the dangerous side effects of that condition.
How is Sleep Disordered Breathing Diagnosed?
The “gold standard” for diagnosis is attended overnight sleep testing in a specialized laboratory. The test is called polysomnography. Measurement of many 14-16 parameters of physiology, including cardio-pulmonary and neurologic, are performed during the subjects’ sleep.
It is now common to utilize portable, self-applied home sleep study (HST) equipment. Guidelines for sleep testing and interpretation are maintained by the American Academy of Sleep Medicine.
How is Sleep Disordered Breathing Treated?
Adjunctive therapies aside, there are only three recommended treatments or management techniques for Sleep Disordered Breathing. They are:
Airway collapsibility is reduced or eliminated by the incremental advancement of the mandible. The pharynx is dilated which slows airflow and increases pressure. The lateral walls of the pharynx are more resilient and the proximity of the tongue to the soft palate and posterior wall of the pharynx is reduced. The tone of the genio-glossus muscle (the tongue) is increased which reduces the collapse of the tongue base during the most relaxed stages of sleep.
There are many designs for custom and non-custom appliances.
They vary in materials used, method of mandibular advancement, fixed position or mobility for the protruded mandible. We invite you to contact Dr. Moore via email or telephone to discuss the options that exist.
Airway collapsibility is reduced by the application of increased air pressure which “splints” the airway open. Dr. Moore has innovated techniques for the management of the very high PAP cases by blending mandibular re-positioning with PAP. Dr. Moore invites questions or comments regarding the management of the full spectrum of OSA severity.
Surgery can be used to remove or reposition redundant tissue to reduce the noise of snoring and the potential for obstructions. Resulting airway volume increases may increase air pressure. Radio-frequency ablation (“Somnoplasty”) of the soft palate may reduce the volume of tissue while preserving its anatomy.
Nasal surgery can be a very effective adjunct therapy to either of the other methods.
Although not covered by guidelines of the AASM, Dr. Moore has documented significant improvements in OSA management using combined therapy (the addition of PAP to the Oral Appliance Therapy).
Compliance is often enabled or improved significantly, presumably due to a reduction in pressure requirement if the pharynx is already mechanically dilated. The synergism is undoubtable and will soon be appearing in conventional sleep medicine practices as the obvious benefits of pressure reduction (20-70%) and its concomitant leak and leak arousal reduction becomes well known. Claustrophobia can be effectively managed by the elimination of mask straps by attaching the interface directly to the oral appliance. This facilitates side sleep posture again reducing PAP pressure requirements.
Nasal airway management, weight loss and fitness training, position therapy, sleep environment management and of course PAP if needed.
How is the best treatment for individual patients determined?
It is important to be referred to a specialist in sleep medicine who can properly diagnose the severity of the disorder and to prescribe the appropriate therapy.
Dr. Richard W. Moore is retained by Comfort Acrylics, Inc as a consultant to assist visitors to our site or callers to our company. He will be able to help you find board certified sleep centers and physicians in your area to assist you. He can also help find dentists credentialed by the Academy of Dental Sleep Medicine who can assist you with oral appliance therapy and can answer or find answers to your questions in any aspect of sleep medicine.