Treatment of Obstructive Sleep Apnea

There are four recognized treatment regimens for obstructive sleep apnea: oral appliances, lifestyle changes, continuous positive airway pressure and surgery.

Decisions on treatment are customized for each patient based on the medical history, sleep specialist's examination, results of the sleep lab study, the individual's unique needs, preferences, health problems and life style. Success of the selected treatment can and should be verified by a repeat study in the sleep lab.

Oral Appliances for the treatment of apnea, hypopnea and snoring are fabricated and fitted by dentists. There are two main categories of oral appliances - Tongue Retaining Devices (TRDs) and Mandibular Advancement Devices (MADs). Both result in the tongue being in a more forward position than normal and the mouth being held open beyond its normal rest position. They presumably keep the airway open by preventing collapse of the tongue on the soft palate and throat.

TRDs utilize the suction generated into a rubber bulb to actively pull and hold the tongue into a forward position protruding beyond the incisor teeth. The lower jaw, which is attached to the tongue, is passively pulled forward. Because the mouth must be sealed around the TRD to sustain the necessary suction, its use is absolutely contraindicated in patients who are mouth breathers. A patent nasal airway is a cardinal principle in prescribing a TRD.

MADs are fabricated over the teeth so the lower jaw is held more open and protrusive than in the normal biting position. In the MAD the mandible is actively pulled forward and the anterior repositioning of the tongue is passive. Scientific studies have demonstrated that MADs dilate pharyngeal muscles, thus helping prevent collapse of a drooping soft palate. The modified jaw position in a MAD raises the hyoid bone relative to cranial base and extends the neck to a position similar to the one in which CPR is initiated, thus helping maintain an open airway. MADs lower elevator muscle activity, reducing clenching and preventing bruxism. They increase volume of space for the tongue in the mouth. Further, some MADs correct dysfunctional swallowing and some have been shown to increase nasal airflow.

	Mandibular Advancement Device

Both MADs and TRDs have advantages and disadvantages. At the present time there are over fifty different mandibular advancement devices available for dentists to choose from. No one yet is the perfect device. MADs are generally more comfortable and better tolerated by most patients than TRDs. MADs can be made for patients with nasally compromised breathing. The overwhelming majority of oral appliances currently being prescribed for apnea and snoring are MADs.

Whichever oral appliance is prescribed for OSA and snoring, as with all other alternative treatment regimens, there is no guarantee of success. Various home monitors are available to objectively evaluate progress each time the device is adjusted. After the dentist has adjusted the oral appliance to maximum performance a final study should be done in the sleep lab to confirm results. The gold standard is still polysomnography.

Oral appliances are not always as effective as CPAP. The importance of titration adds to the cost. Because it is time consuming for the dentist to repeatedly adjust and then measure outcome each time, their cost may be higher than CPAP.

There are side effects to the use of oral appliances. There is an initial accommodation period of getting used to sleeping with a foreign device in the mouth. Symptoms such as tooth discomfort and excessive salivation are common. In the morning when the appliance is removed, there is often a period of 15 - 45 minutes necessary for the jaw to reprogram itself from the forward bite to the habitual bite. Occasionally, there is some tooth movement and bite change as a side effect. Rarely are they serious enough to discontinue using the appliance, but regular, semi-annual check-up visits to the dentist are important.

One problem with oral appliances is that dental work done after fitting and adjustment has been completed may seriously compromise fit and function. Major dental work done subsequent to fitting the appliance could necessitate a remake. Any anticipated dental work should be done before fabrication of an oral appliance for snoring and/or apnea.

Continuous Positive Airway Pressure (CPAP) is the most common long term treatment recommended for obstructive sleep apnea, hypopnea, upper airway resistance syndrome, snoring and even central apnea. The patient wears a mask over their nose, or nose and mouth during sleep. The CPAP machine blows air via a tube through the mask, and the pressure is adjusted to a level sufficient to prevent the airway from collapsing during sleep. Polysomnography is used to set the appropriate CPAP level during a night's sleep at the sleep lab. The advantage of CPAP is that it almost always works, its cost is reasonable and it is easily titrated. One of the few contraindications is a patient with complete nasal blockade. Among its disadvantages are that patient compliance is low. It is difficult to travel with CPAP, it seems to be a deterrent to sex life, the mask is often uncomfortable, The masks can develop air leaks, skin can become irritated from the mask, excessive morning dry mouth is possible, some complain of abdominal bloat and noise of the pump is obtrusive.

	Different Models of CPAP Mask

Lifestyle Changes should not be overlooked as an important part of a comprehensive program to treat OSA. Positive lifestyle changes do work, but based on the human psyche, they are difficult to maintain and keep. They require a strong lifetime commitment. They should be utilized, but in perspective to each patient. They usually are most effective as augmentation to other physical regimens.

• No alcohol - alcohol relaxes the muscles of the upper airway during sleep
• No sedatives - sedatives also relax the muscles of the upper airway during sleep, thus facilitating airway collapse
• Eliminate the source of nasal congestion - irritants and allergens can stimulate an allergic reaction, swelling nasal membranes and blocking nasal airflow
• No smoking - smoking causes inflammations and swelling of the upper airway which restricts airflow.
• Regulate sleep hours - the body regulated by a circadian rhythm cycle, a natural internal body clock; there are patterns of brain wave activity and hormone regulation and regeneration that depend on cues given by the biological clock; upsetting these rhythms can disrupt normal biological function and distress the entire system
• Weight loss - excessive weight causes deposition of fat in the pharyngeal tissue, adding to a narrower airway passage and increased chance of collapse
• Sleep on the side - in some patients the apnea or snoring only occurs when they sleep on their back; there are some physical devices of the market to help but retraining sleep position to the side is of major importance

Surgery is a widely utilized treatment regimen for OSA, hypopnea, UARS and snoring. The goal of surgery is to prevent the airway from collapsing during sleep. The many different surgical procedures are directed at increasing airway size and stiffness, eliminate excess tissue in the airway, and correcting jaw deformities that predispose or contribute to compromised airway function.

The key to success is to correctly identify before surgery, the tissue that is causing the airway collapse so the correct procedure can be performed. At this point in the state of the science surgery by most estimates is successful at eliminating OSA 40 - 50% of the time. More than one procedure is often tried before the patient perceives any benefit.

There is debate in the medical literature whether OSA is an anatomic problem or not. Some academics argue that upper airway obstructers are not essential to have apnea. Their position is that apnea is based on a reduced neural compensation by the brain that initially lowers the muscle activity before the actual airway collapse. To strengthen their case they point out that all people with narrow airways and large tonsils get apnea. They believe that is why surgery is not more successful. The focus of their research is directed at optimizing neural drive to the muscles that maintain airway patency during sleep. "Keep the airway awake and let the brain sleep" is their operative goal.

Certainly apnea and snoring are difficult and complex problems. No regimen currently in use is successful on all patients. Each treatment modality has its successes and its not so successful results. OSA, if untreated will not get better and it will get worse. The life threatening morbidity of obstructive sleep disorders means the one alternative that is not acceptable is ignoring the problem.

 Comparison chart for recognized treatment regimens for obstructive sleep apnea.