WORKUP

Lab Studies:

• Routine laboratory evaluation

• Routine laboratory tests usually are not helpful unless a specific indication is present.

• Consider obtaining a thyroid-stimulating hormone level if clinically indicated, particularly in elderly individuals.

• An arterial blood gas determination should be obtained if obesity hypoventilation syndrome (or another cause of significant pulmonary hypertension) is suspected.

Imaging Studies:

• The modalities available for identifying the site of obstruction include lateral cephalometry, endoscopy, fluoroscopy, CT scan, and MRI.

• The accuracy of these methods in identifying the site(s) of obstruction is not clear.

• Currently, UA imaging is used primarily as a research tool.

• Routine radiographic imaging of the UA in the initial evaluation of SDB is of uncertain benefit currently and should not be performed unless a specific indication is present.

• UA imaging studies (cephalometrics, MRI, CT scan) should be performed in patients being evaluated for UA and craniofacial surgery. Cephalometrics may be useful in some patients being evaluated for oral appliance therapy.

Other Tests:

• Standard diagnostic nocturnal polysomnography

• In-laboratory overnight PSG has been the standard method for evaluating SDB for many years. Complete PSG is a multichannel recording of sleep and breathing and usually involves in-laboratory measurement of sleep architecture and EEG arousals, eye movements, chin movements, airflow, respiratory effort, oximetry, ECG, body position, snoring, and leg movements.

• The ASDA has published standards and guidelines for performing PSGs. The ASDA recommends the following:

   

  • PSG is indicated for the diagnosis of possible OSA.

     

  • A minimum duration of 6 hours of PSG evaluation is required for diagnosis.

     

  • Standard diagnostic PSG may be performed in a health care facility or in the patient's home with a trained technician in attendance.

• Data are collected in the laboratory in the presence of a qualified technician (full PSG with attended monitoring); this protocol provides the opportunity for direct observation of a variety of sleep-associated disturbances (eg, apneas, periodic leg movements, seizures, rapid eye movement [REM] behavior disorder). Patients who regularly work night shifts should have PSG performed during the day, to match their normal sleep-wake cycle.

• Arousals detected on PSG are important to help evaluate the degree of sleep fragmentation. They may be the only clue to UA resistance syndrome in a patient with daytime hypersomnolence if esophageal pressure monitoring is not performed. Esophageal pressure monitoring is not performed routinely in most laboratories due to the invasive nature of the procedure.

• The following PSG findings are characteristic of OSA:

   

  • Apneic episodes occur in the presence of respiratory muscle effort (see Image 2).

     

  • Apneic episodes of longer than 10 seconds in duration are considered clinically significant. Apneic episodes usually are approximately 20-40 seconds in duration, rarely lasting up to several minutes.

     

  • Apneic episodes are more prevalent during REM sleep and, in some patients, may occur exclusively during REM sleep.

     

  • Patients may experience a combination of apneas and hypopneas, or they may experience one or the other exclusively.

     

  • Mixed apneas may occur. Mixed apneas are a combination of central sleep apnea and OSA in a single apnea episode.

     

  • Sleep disruption due to arousals usually is seen at the termination of an apnea.

• Split-night study PSG

• In an attempt to reduce costs, the trend has been to perform split-night studies (ie, single-night studies), in which the initial part of the study is used for diagnosis of OSA and the latter part is used for continuous positive airway pressure (CPAP) titration. Recent data suggest that this approach is cost effective.

• ASDA guidelines for split-night studies include the following:

   

  • Patients with an RDI greater than 40 events per hour during the first 2 hours of a diagnostic PSG receive a split-night study PSG. The final portion of the study is used for CPAP titration.

     

  • Split-night studies may be considered for patients with an RDI of 20-40 events per hour, based on clinical observations, such as the occurrence of obstructive events of prolonged duration or the occurrence of marked oxygen desaturation.

     

  • A minimum of 3 hours of sleep is preferred to adequately titrate CPAP after this treatment is initiated.

     

  • Split-night studies require recording and analysis of the same parameters as a standard diagnostic PSG.

     

  • A single split-night study may not permit adequate titration of CPAP therapy. If treatment does not control symptoms, an additional full-night CPAP titration may be required.

• Indications for repeat PSG are as follows:

• Symptoms persist despite adequate compliance with prescribed CPAP treatment.

   

• PSG can be used to assess response to UA surgical procedures.

   

• It also can be used to assess response to oral appliance therapy.

   

• If a significant sustained weight change (>15%) occurs, PSG should be repeated.

   

• If the first PSG is of poor quality, a repeat is indicated.

• Unattended polysomnography

• According to the ASDA polysomnography task force report, unattended portable PSG in the patient's home may be effective for the diagnosis of severe SDB when used by a qualified sleep specialist as part of a comprehensive sleep consultation.

• Any patient initially tested using unattended portable PSG studies who does not have a satisfactory diagnosis must have easy and automatic access to a comprehensive sleep consultation and additional diagnostic testing. Therefore, a home-testing program dedicated to quality care should either originate from or have some formal affiliation with a comprehensive sleep disorders center so that the continuum of patient care is ensured.

• Limited polysomnography studies

• A portable monitoring device is being used for limited-channel in-laboratory diagnostic PSG studies (cardiopulmonary monitoring). ASDA guidelines suggest that limited PSG should include (1) oronasal airflow, (2) chest wall respiratory effort, (3) ECG, and (4) oxyhemoglobin saturation.

• In-laboratory limited PSG studies show fairly good correlation with standard PSG, but limited data are available to compare unattended cardiopulmonary recordings in the home setting with standard PSG in the sleep laboratory. The role of unattended PSG studies for the diagnosis of SDB is uncertain at present because of a lack of supportive data. These studies may be indicated for the following:

   

  • Patients with severe symptoms indicative of OSA require limited studies when initiation of treatment is urgent and standard PSG is not readily available.

     

  • Patients with established OSA who require follow-up studies should have limited PSG.

     

  • Patients who are unable to be studied in the sleep laboratory should have limited PSG.

   

• Limited-channel studies are less accurate than the standard PSG in determining obstructive events, particularly hypopneas. Also, they are not helpful for detecting non-OSA sleep disorders that may coexist with OSA.

• Evaluation of sleepiness

• The multiple sleep latency test traditionally has been used to quantify sleepiness in patients with symptoms of daytime hypersomnolence.

   

  • It must be performed on the day following a standard PSG.

     

  • The patient is instructed to attempt sleeping for 20 minutes on each of 4 separate naps, each nap being 2 hours apart.

     

  • The average latency to stage 1 sleep is determined for the 4 naps, and a mean sleep latency of less than 5 minutes is considered abnormal (ie, indicative of pathological sleepiness).

     

  • A mean sleep latency of more than 10 minutes is normal.

     

  • The test is not performed routinely following PSG for the diagnosis of OSA.

• The Epworth sleepiness scale is a self-administered questionnaire that measures predisposition towards sleep (ie, subjective measure of sleep).

   

  • It may be useful when excessive daytime somnolence complaints are out of proportion to actual OSA findings on PSG.

     

  • This test does not appear to correlate well with the RDI or the multiple sleep latency test. Therefore, its usefulness as a general screening tool for SDB is questionable.

TREATMENT

Medical Care: Little evidence supports the treatment of asymptomatic patients with an RDI that is in the mild range. Patients with mixed apneas should be treated as if they have OSA because OSA is most life-threatening and central sleep apnea abates commonly with OSA treatment. Only health care professionals with adequate training in the evaluation and management of OSA should prescribe therapy for patients with SDB. CPAP should not be prescribed without PSG confirmation of the correct CPAP pressure level because no standardized pressure value exists based on age or body mass index.

The primary treatment for OSA is positive pressure therapy, and nasal CPAP is the most commonly prescribed type of therapy. Other forms of positive airway pressure include bilevel positive airway pressure and variable CPAP. Nightly use of at least 4 hours of CPAP is required to produce consistent ameliorative effects. Data show that compliance at 1 month predicts compliance at 3 months. Whether patients like CPAP depends on their perception of improvement, not on the severity of their disease as judged by the clinician.

Variable CPAP (sometimes called autoCPAP) is administered through a new device whose niche has yet to be defined. The basis for variable CPAP is that changes in pressures needed by a patient depend on factors such as body position, sleep stages, sleep deprivation, sedative use, and alcohol use, among others.

• Nonsurgical therapy

   

  • General/behavioral measures such as weight loss and avoidance of alcohol, sedatives, and supine position are elements of nonsurgical treatment.

     

  • Mechanical measures include (1) positive airway pressure therapy with CPAP or bilevel positive airway pressure or (2) oral appliance therapy.

     

  • Pharmacologic therapy is not part of treatment. No clinically useful drug therapy is currently available.

   

• Nasal CPAP therapy - General considerations

   

  • Initially described in 1981, this is currently the treatment of choice for patients with OSA and UA resistance syndrome.

     

  • Continuous positive pressure is applied to the (UA) with a nasal mask, nasal pillows, or a mask that covers both the nose and mouth (ie, oronasal mask)

     

  • CPAP acts as a pneumatic splint to maintain UA patency during sleep, and it is very effective in the treatment of SDB.

     

  • CPAP consists of a blower unit that produces positive-pressure airflow. This usually is applied at the nose, and the airflow is then directed down through the UA.

     

  • CPAP increases airway caliber in the retropalatal and retroglossal regions. It increases the lateral dimensions of the UA and thins out the lateral pharyngeal walls. The lateral pharyngeal walls are thicker in patients with OSA than in patients without OSA.

     

  • Application of adequate levels of nasal CPAP during sleep almost always results in resolution of (1) obstructive apnea/hypopnea, (2) oxyhemoglobin desaturation, and (3) RERAs from sleep and results in adequate sleep continuity.

   

• CPAP therapy - Efficacy and compliance

   

  • CPAP therapy improves daytime hypersomnolence, daytime alertness, and neuropsychiatric functioning.

     

  • It improves right heart function, left heart function in patients with left ventricular dysfunction, and systemic and pulmonary hypertension.

     

  • Patients have improvement in their quality of life.

     

  • Some studies report improved survival rates.

     

  • The beneficial effects parallel those observed following tracheostomy.

     

  • CPAP therapy is effective for treating mixed apneas and some central apneas.

     

  • Compliance may be poor. Although an average of 20-40% of patients do not use the prescribed therapy, some sleep disorders centers have achieved greater than 90-95% compliance rates with CPAP therapy. In the authors’ experience, regular, close, and personalized follow-up greatly enhances compliance.

   

• CPAP therapy - Complications and adverse effects

   

  • Pressure/airflow-related complications include (1) the sensation of suffocation/claustrophobia, (2) difficulty exhaling, (3) the inability to sleep, (4) musculoskeletal chest discomfort, (5) aerophagia, and (6) sinus discomfort. Pneumothorax/pneumomediastinum (extremely rare), pneumoencephalos (isolated case report), and tympanic membrane rupture (very rare) can occur.

     

  • Mask-related problems could include skin abrasions, rash, and conjunctivitis (due to air leak).

     

  • Nasal problems can include (1) rhinorrhea, (2) nasal congestion, (3) epistaxis, and (4) nasal/oral dryness.

     

  • Other problems include noise and spousal intolerance.

• Nasal CPAP therapy – Guidelines for use

• Patients with severe SDB (RDI >20-30) should be treated irrespective of symptoms because of the increased risk of cardiovascular morbidity.

   

• Patients with an RDI of 5-20 should be treated if symptomatic or if coexistent cardiovascular disease is present. Patients with UA resistance syndrome may need CPAP therapy.

   

• CPAP titration is performed following the diagnostic portion of a split-night protocol or on a separate night following a diagnostic PSG.

   

• Proper titration includes identifying the minimum CPAP level that abolishes obstructive apneas/hypopneas, oxyhemoglobin desaturation, RERAs, and snoring in all sleep stages and in all sleep positions. Typically, the pressure needed is 5-20 cm water.

• Bilevel positive airway pressure therapy

   

  • In contrast to CPAP, which delivers a constant pressure during both inspiration and expiration, bilevel positive airway pressure permits independent adjustment of the pressures delivered during inspiration and expiration.

     

  • The ability to set independent inspiratory positive airway pressure (IPAP) and expiratory positive airway pressure (EPAP) levels results in lower mean airway pressures compared to CPAP.

     

  • In a given patient, the EPAP level that needs to be applied is lower than the corresponding CPAP level that will be required to maintain airway patency.

     

  • No studies have conclusively demonstrated improved compliance with bilevel positive airway pressure devices compared to CPAP therapy.

     

  • A trial is warranted in patients who are unable to tolerate CPAP. However, it is too expensive to be used as first-line therapy and has no distinct advantages over CPAP therapy.

• Oral appliance therapy

• The 2 main groups of oral appliances are tongue repositioning devices (TRD) and anterior mandibular positioners (AMP)/mandibular advancing devices.

   

• Oral appliances are believed to be effective for the following reasons:

   

  • They increase the size of the UA by moving (pulling) the tongue forward (ie, TRD) or by moving the mandible and soft palate anteriorly (ie, AMP).

     

  • Oral appliances cause thinning of the lateral pharyngeal walls by exerting traction. According to imaging studies, the size of the lateral pharyngeal fat pads and the thickness of the lateral pharyngeal muscular walls are greater in patients with apnea than in healthy subjects.

   

• The biomechanical factors responsible for the efficacy of oral appliances are not completely understood.

   

• A review of the literature by the ASDA indicates the following summary:

   

  • Overall, 51% of patients studied achieved an RDI of less than 10 per hour with oral appliance therapy.

     

  • Of patients who had a pretreatment RDI greater than 20, 39% continued to have an RDI above this level despite oral appliance therapy.

     

  • No patient characteristics were found that predicted success with oral appliance therapy.

     

  • No particular oral appliance had any advantages over the others studied.

   

• Subsequent prospective controlled clinical trials comparing oral appliance therapy to nasal CPAP therapy for the treatment of OSA and snoring demonstrated the following:

   

  • Treatment was successful in 55% of patients using an adjustable AMP and in 48% of patients using a nonadjustable AMP. Treatment success was defined as a posttreatment RDI equal to or less than 10 events per hour, with symptomatic relief.

     

  • CPAP therapy was superior to AMP therapy in normalizing the RDI, reducing snoring, and improving oxygenation.

     

  • Daytime sleepiness was improved equally by CPAP and AMP therapy.

     

  • The majority of patients preferred AMP therapy to CPAP therapy.

     

  • Treatment success with AMPs appears to be inversely related to the initial RDI.

   

• The most recent trial, the largest to date, evaluated the effectiveness of an adjustable mandibular positioning device; no comparison was made to CPAP therapy.

   

  • Treatment with the device was successful in 51% of patients (posttreatment RDI <10/h), 86% of patients continued to use the appliance nightly approximately 1 year after trial commencement, and up to 32% of patients had teeth discomfort with the appliance.

     

  • Six of 21 patients with severe OSA (RDI 50-115/h) were treated successfully with this device (posttreatment RDI <10/h).

   

• The 1995 ASDA practice parameters for the treatment of snoring and OSA with oral appliances include the following:

   

  • Oral appliances are indicated for use in patients with primary snoring or mild OSA who do not respond to or are not appropriate candidates for treatment with behavioral measures such as weight loss or sleep-position change.

     

  • Patients with moderate-to-severe OSA should have an initial trial of nasal CPAP therapy because greater effectiveness has been shown with this intervention than with the use of oral appliances.

     

  • Oral appliances are indicated for patients with moderate-to-severe OSA who are intolerant of or refuse treatment with nasal CPAP. Oral appliances also are indicated for patients who refuse or are not candidates for tonsillectomy and adenoidectomy, craniofacial operations, or tracheostomy.

   

• According to the above guidelines, the major role for oral appliance therapy appears to be in patients with mild-to-moderate OSA who are intolerant of CPAP (and bilevel positive airway pressure) therapy. These devices are less likely to benefit patients with severe OSA.

   

  • Clinicians and patients prefer a titratable device such as an AMP because it can be adjusted to improve both efficacy and comfort.

     

  • Patients should have a complete evaluation by a sleep disorders specialist and a dental professional, both of whom should be experienced in oral appliance therapy; close collaboration is required.

     

  • Follow-up PSG after final adjustment of the device is recommended to ensure that OSA has been treated adequately, particularly in patients with moderate-to-severe OSA.

     

  • These devices may abolish snoring without adequately treating OSA.

   

• Complications and/or adverse effects include the following:

   

  • Excessive salivation has been reported, as has dental misalignment.

     

  • Temporomandibular joint pain/discomfort is possible. The patient should not have significant discomfort or difficulty opening the jaw upon waking in the morning.

     

  • Patients may object to having an appliance in their mouth throughout the night.

Surgical Care: A specific space-occupying lesion causing UA obstruction is found in only 3 of 200 adult patients with OSA. Although surgical correction of such an abnormality (ie, tonsillectomy) could potentially cure OSA, the majority of adult patients do not have such correctible lesions.

A functional division of the pharynx into retropalatal/oropharyngeal (region posterior to the soft palate) and retrolingual/hypopharyngeal (region posterior to the vertical portion of the tongue) regions has been proposed.

The level of obstruction in patients with SDB is classified into 3 types. Type I is obstruction in the retropalatal region only. Type II is obstruction in both the retropalatal and retrolingual regions. Type III is obstruction in the retrolingual region only.

Different surgical procedures have been proposed for patients with different levels of obstruction. Uvulopalatopharyngoplasty (UPPP) may correct type I obstruction. Genioglossus advancement with hyoid myotomy (GAHM) may correct type III obstruction. Maxillomandibular advancement osteotomy (MMO) may correct obstruction at all levels.

Based on the recognition that several sites of obstruction could be responsible, a systematic approach for selecting surgery has been developed. This is the Riley-Powell-Stanford surgical protocol designed in 1988. The protocol has 2 phases. Phase I consists of the UPPP and GAHM procedures, and phase II consists of the more complicated MMO procedure. Patients who are not adequately treated with phase I surgery are offered phase II surgery.

For phase I surgery, perform UPPP for patients with type I obstruction, GAHM for patients with type III obstruction, and simultaneous UPPP and GAHM for patients with type II obstruction. The overall success rate for phase I surgery is approximately 61%, although patients with severe OSA (RDI >60, lowest oxyhemoglobin saturation <70%) have a success rate of only 42%.

Phase II surgery consists of MMO, which advances the jaw anteriorly. Using the phased protocol, the success rate has been in excess of 90% for phase II surgery.

In some patients, tracheostomy or continuous positive air pressure (CPAP) therapy is required in the perioperative period to ensure a safe airway.

The success of these surgical procedures depends on accurate identification of the site of obstruction in the UA. The modalities available for identifying the site of obstruction include lateral cephalometry, endoscopy, fluoroscopy, CT scan, and MRI. The accuracy of these methods in identifying the site(s) of obstruction is not clear. Success rates for UPPP have been only approximately 50% despite preselection of patients with type I obstruction based on these studies.

Data on surgical therapy for OSA are mainly from case series. The phased protocol of Riley-Powell-Stanford holds promise for achieving cure in patients with OSA, but further data from controlled clinical trials are needed to decide its role in the overall management of OSA.

The success rates quoted are from select centers with surgeons highly skilled in these special procedures; these results cannot be extrapolated to the general population of patients with OSA. All patients undergoing surgery for treatment of OSA should have a follow-up PSG.

• Uvulopalatopharyngoplasty

• UPPP is the most common surgical procedure performed for adults with OSA and was introduced to the United States by Fujita and colleagues in 1981. It involves removal of the tonsils (if present), uvula, distal margin of the soft palate, and redundant pharyngeal tissue and reshaping of the soft tissues in the lateral pharyngeal walls.

   

• The surgical success rate is approximately 50% when surgical success is defined as both 50% reduction in RDI/AI and a postoperative RDI of less than 20 (or an AI <10); this is despite preselection of patients with type I obstruction using imaging and endoscopic studies. This highlights the inadequacy of the methods available to identify sites of UA obstruction. The outcome of UPPP is difficult to predict.

   

• Although the procedure usually is well tolerated and uneventful, complications can include the following:

   

  • Pain upon swallowing and pain with speech, usually for 1-2 weeks postoperatively

     

  • Hemorrhage (2-4%)

     

  • Swallowing difficulties, particularly regurgitation of food

     

  • Long-term pharyngeal discomfort

     

  • Disturbance in taste

     

  • Numbness of tongue

     

  • Nasopharyngeal stenosis

   

• Silent apnea may result. UPPP may abolish snoring but have no significant effect on sleep-associated obstructive episodes. It is imperative that patients have a postoperative PSG to rule out persistent OSA.

   

• The ASDA recommendations for UPPP are as follows: “The UPPP, with or without tonsillectomy, may be appropriate for patients with narrowing or collapse in the retropalatal region. Good preoperative evaluation does not guarantee surgical success; the effectiveness of the UPPP is variable, and the procedure should be considered when non-surgical treatment options, such as CPAP have been considered.”

   

• Prior UPPP surgery reduces the maximal level of pressure tolerated by patients requiring CPAP therapy; it also may compromise subsequent CPAP therapy by promoting mouth leaking.

   

• Uvulopalatopharyngoglossoplasty (UPPPG) is a modified UPPP with limited resection of the base of the tongue, enlarging both the retropalatal and retrolingual regions of the UA.

• Genioglossus advancement with hyoid myotomy

   

  • The genioglossus muscle is repositioned anteriorly through an inferior mandibular osteotomy (genioglossus advancement). This places the pharyngeal muscles and the base of the tongue on tension and results in airway expansion.

     

  • The hyoid is suspended to the superior edge of the larynx and fixed in this position, adding to the effect of genioglossus advancement.

• Maxillomandibular advancement osteotomy

• The midface, palate, and mandible are moved forward in this procedure, increasing the space behind the tongue and also increasing the tension on the genioglossus muscle.

   

• This surgery is more extensive than any of the others described. It usually is reserved for patients in whom other modalities of treatment fail.

• Tracheostomy

• This procedure bypasses the UA and is the most effective surgical procedure for treatment of OSA; it is virtually 100% effective.

   

• Unfortunately, it is a disfiguring procedure and results in decreased quality of life.

   

• Tracheostomy is now reserved for patients with very severe OSA in whom other medical and surgical treatment modalities have failed. Tracheostomy also is used for airway protection during UA reconstructive surgery.

• Other surgery options

   

  • Laser-assisted uvulopalatoplasty: Although successful in reducing snoring in 90% of patients, the success rate in patients with SDB is not clear. It may give rise to more scarring than UPPP and could potentially worsen apnea. Increased OSA severity in the early postoperative period following laser-assisted uvulopalatoplasty has been noted. It is not recommended for treatment of OSA until further data are available.

     

  • Laser midline glossectomy and lingualplasty: These 2 procedures enlarge the retrolingual region by using a laser to remove a portion of the posterior tongue. The role of the procedures in the management of SDB has yet to be defined.

     

  • Nasal surgery: This includes septoplasty, turbinectomy, and polypectomy and may be useful as an adjunct to other procedures or to improve CPAP compliance. Nasal surgery by itself is rarely effective for the treatment of OSA.

• Radiofrequency volumetric tissue reduction of the soft palate (somnoplasty)

   

  • Recent interest has been generated in this new technique pioneered by Powell and associates that used radiofrequency energy to ablate the soft palate. This procedure has US Food and Drug Administration (FDA) approval for the treatment of snoring and OSA.

     

  • A midline soft palate submucosal scar is created by the use of a needle electrode inserted near the border of the hard palate and directed toward the uvula. Pulses of radiofrequency energy are delivered, resulting in tissue necrosis and needle tract fibrosis over subsequent weeks to months.

     

  • A study in 22 patients with mild SDB demonstrated a reduction in the volume of palatal tissue and improvement in symptoms in all subjects, but no data are available regarding improvement of RDI and oxyhemoglobin saturation.

     

    • Long-term follow-up (12-18 mo) revealed that approximately 41% of patients undergoing radiofrequency volumetric reduction of the soft palate develop recurrence of snoring.

       

    • Evidence showed postsurgical improvement in the severity of esophageal pressure swings, indicating that this treatment may be useful in patients with UA resistance syndrome.

     

  • A more recent study of radiofrequency volumetric reduction of the soft palate (12 patients) again demonstrates success in treating snoring, but data regarding adequate treatment of SDB are lacking. Data from larger controlled studies are required before this technique can be recommended for the treatment of SDB; it appears to be associated with less morbidity than UPPP, laser-assisted uvulopalatoplasty, and lingualplasty.

     

  • Animal studies of radiofrequency volumetric reduction of the tongue have shown volume reduction in tongue tissue after treatment. Results of human studies are pending.

• The ASDA recommendations for surgery

   

  • Nasal CPAP is the recommended initial therapy for patients with moderate-to-severe OSA (RDI >20, lowest oxyhemoglobin saturation <85%). Patients with symptomatic mild OSA also may prefer nasal CPAP therapy.

     

  • Surgery is indicated in patients who have a specific underlying abnormality that is causing the OSA.

     

  • Surgery may be indicated if noninvasive medical therapy (nasal CPAP or oral appliance) has failed or has been rejected, provided the patient desires such therapy and is medically stable enough to undergo the procedure. If the patient has OSA that is moderately severe or severe (RDI >40 or lowest oxyhemoglobin saturation <80%), the patient requires perioperative airway protection with either nasal CPAP or a tracheostomy.

     

  • Surgery is indicated as initial therapy for patients with mild OSA (RDI <20, lowest oxyhemoglobin saturation >90%) if medical therapy has been refused or rejected, provided they are medically stable enough to undergo the procedure.

Consultations:

• Patients should have a complete evaluation by a sleep disorders specialist and a dental professional, both of whom should be experienced in oral appliance therapy; close collaboration is required.

Diet:

• Obesity (body mass index >29 kg/m²) is the most important predictor of sleep apnea. In patients who are obese, OSA may be reduced or corrected by weight reduction. In these patients, a 10% reduction in weight has been shown to reduce sleep apnea/hypopnea indices in half.

   

• Some of the benefits of weight reduction in patients with SDB include the following:

• Decreased RDI

   

• Lower blood pressure

   

• Improvements in pulmonary function and arterial blood gas values

   

• Improvements in sleep structure and snoring

• The required optimum CPAP pressure may be reduced with weight loss.

• One of the most important determinants of relapse of OSA following surgical treatment is weight gain. Although accomplishing and maintaining weight reduction are difficult, the results are extremely beneficial when patients are able to do so.

• The treatment approach to SDB would not be complete if weight reduction is not addressed in patients who are obese.

Activity:

• Restriction of body position during sleep

• SDB is worse in the supine position, and some patients have apnea only in this position.

   

• Preventing the patient from assuming the supine position by using devices such as a snore ball (a tennis ball sewed onto the pajama back) or a gravity-activated position monitor may be useful, but these devices are cumbersome and appear to benefit only patients with very mild OSA.

   

• Patients with marked obesity may benefit from sleeping in an upright position.

   

• More recently, the FDA has approved a specially designed pillow (PillowPositive) for the treatment of snoring and mild OSA. This device maintains head and neck position during sleep to optimize UA patency.

• Patients should avoid alcohol and other sedatives known to make apnea worse.

   

• Patients should avoid smoking.

• Smoking increases the risk of snoring and apnea.

• Smoking cessation appears to decrease risk.

   

• Individuals who smoke also are more likely that those who do not smoke to complain of problems going to sleep, problems maintaining sleep, and increased daytime somnolence.

• Patients should avoid sleep deprivation.

MEDICATION

Although acetazolamide, medroxyprogesterone, fluoxetine, and protriptyline have been used for the treatment OSA, none of these therapies is recommended.

FOLLOW-UP

Further Outpatient Care:

• Nasal CPAP therapy

• Many patients note an immediate improvement in alertness, concentration, and memory; but achieving maximum improvement in neurocognitive symptoms may take as long as 2 months of CPAP therapy.

   

• Adequate adherence is defined as more than 4.5 hours of CPAP use per night, routinely.

   

• Follow-up visits should be scheduled at least once following initiation of CPAP treatment and at least yearly thereafter. Follow-up evaluation is required to ensure symptomatic improvement, CPAP compliance, and equipment maintenance.

• CPAP therapy - Compliance issues

• Nasal congestion can be treated with antihistamines and/or topical corticosteroids.

   

• Nasal dryness can be treated with topical saline sprays or humidification.

   

• If the air generated by unit is too cold, the patient should use a heated humidifier.

   

• If excessive air leak through mouth occurs, patients should use a chin strap to keep their mouths closed, or, they should try the oronasal mask. Consider consultation with an otolaryngologist to rule out sinus dysfunction.

   

• If a poorly fitting mask causes skin break down and/or air leaks, patients should try different mask sizes and models; a variety of interfaces are now available.

   

• For claustrophobia, patients may try nasal pillows or behavioral management.

   

• If patients feel a sensation of increased resistance to expiration, use of a CPAP unit with a ramp feature is indicated. This permits the patient to fall asleep with little or no pressure applied, and the pressure gradually increases to the set optimal level over a predetermined time interval (usually 15-30 min). Alternatively, bilevel positive pressure may be used.

• Oral appliance therapy

• Regular follow-up with a dental professional allows for adjustment of the dental appliance, initially based on symptoms. Follow-up helps ensure compliance with therapy and helps identify adverse effects/complications, device deterioration, or maladjustment.

   

• Follow-up PSG after the final adjustment of the oral appliance ensures that OSA has been adequately treated. However, PSG should be deferred until adequate symptom response and patient comfort have been achieved with adjustments to the appliance.

   

• Follow-up with a sleep disorders specialist ensures that OSA has been adequately treated. Regular follow-up is required until patient’s symptoms have resolved and PSG evaluation shows no evidence of significant SDB. It also helps determine if another treatment modality is required, due to treatment failure or intolerance.

   

• Close collaboration is required between the sleep disorders specialist and dental professional.

• Pay attention to compliance, comfort, dental complications, and evidence of recurrent OSA.

• Surgery

• Follow-up with a sleep disorders specialist ensures that OSA has resolved.

• Follow-up PSG is essential to determine if OSA has been treated adequately. It should be performed once the surgical site has healed adequately. The most effective timing appears to be 4-6 months postoperatively to ensure steady body weight, completion of healing, and stabilization of sleep architecture.

Patient Education:

• Nasal CPAP therapy: Patients should be trained by a physician, trained technician, or nurse for at least the first month of CPAP therapy. This promotes long-term adherence with treatment.

MISCELLANEOUS

Medical/Legal Pitfalls:

• The following is a summary of the American Thoracic Society (ATS) guidelines on sleep apnea, sleepiness, and driving risks.

• Laws regarding impaired drivers, including those with OSA, vary from state to state. In some states, the physician is obligated to report patients under specific conditions (ie, mandatory reporting statute) while other states permit reporting but do not require it (ie, permissive reporting statute).

   

• Mandatory statutes take 1 of the 2 following approaches:

   

  • Categorical approach: The physician is obligated to report patients who have specified medical conditions, such as epilepsy. In these states, the reporting obligation is based on diagnosis alone.

     

  • Functional approach: The physician is required to report patients with certain medical conditions only if the physician believes that a condition impairs the patient's driving ability.

• Irrespective of whether statutory reporting is required, physicians may be liable for damages if a patient with OSA injures himself or someone else while driving.

   

• Assess the risk of driving in any patient with OSA. Criteria that increase this risk are as follows:

• The patient has had previous motor vehicle accidents.

   

• The patient has had near-miss incidents while driving.

   

• Evidence of severe daytime sleepiness or impaired driving performance is present.

• The following should be undertaken in patients with OSA:

   

  • Assess the patient's risk for motor vehicle accidents. In patients at highest risk, the physician should immediately warn the patient of the potential risk of driving until effective therapy is instituted.

     

  • Warn any patient with OSA of the potential dangers of driving while sleepy. Inform the patient of the potential personal and social risk.

     

  • Additional counseling is required depending on other risk factors (eg, occupation).

     

  • Advise patients to not drive until their OSA has been treated adequately.

     

  • Additional counseling to family members may be appropriate, and alternatives to driving may need to be explored for those who are unaware of their sleepiness or unwilling to acknowledge their increased risk.

     

  • Patients should be diagnosed and treated expeditiously.

     

  • Document in writing any warnings, concerns, and/or recommendations given to the patient. This reinforces the importance of the message to the patient and helps reduce the risk of legal liability for medical personnel.

     

  • Have a plan of follow-up to determine the effectiveness of therapy and compliance with therapy, on a routine basis. Ascertain that daytime sleepiness has been significantly reduced or eliminated. Evaluations should be continued at regular intervals until therapy has controlled the condition.

   

• Whether and under what circumstances patients with sleep apnea should be reported to the licensing authority depend on the laws of the state in which the physician practices.

• Physicians taking care of patients with OSA must be aware of state statutes or regulations regarding reporting of high-risk drivers.

   

• Each physician is obligated to adhere to the requirements of the law in the specific state of practice, even if those laws do not reflect sound public policy or medical evidence.

• The ATS guidelines on reporting of patients to the appropriate state authorities are as follows:

• In states with permissive reporting mechanisms, at a minimum, the physician should notify the state’s department of motor vehicles if a highest-risk patient (ie, OSA with severe daytime sleepiness and a previous motor vehicle accident/near-miss incident) is unwilling to restrict driving until effective treatment has been instituted, is not compliant or unwilling to accept treatment, or has an untreatable condition or one that is not amenable to expeditious treatment (within 2 mo of diagnosis).

   

• Increased occupational exposure to driving or increased occupational risk for an accident of significant importance to the public (eg, truck drivers transporting hazardous waste, school bus drivers) may be other indications for reporting.

• According to the ATS guidelines, a diagnosis of OSA without additional risk factors for impaired driving should not be the basis for reporting a patient unless required by state law.

• Categorical reporting may be more appropriate in the context of occupational licenses, but this also is arguable; at a minimum, the threshold for suspicion of increased driving risk due to sleepiness should be lower, given the increased hazard.

   

• The US Department of Transportation convened a group of respiratory experts at a Conference on Pulmonary/Respiratory Disorders in Commercial Drivers in September of 1990. The report from this group recommends that operators with suspected sleep apnea should not be medically qualified for commercial vehicle operation "until the diagnosis has been eliminated or accurately treated."

   

• A US Federal Aviation Administration specification letter entitled "Sleep Apnea Evaluation Specifications" states that the complications of OSA present a risk to flying safety and recommends an initial workup, acceptable treatments, and follow-up for pilots being evaluated for OSA.

Special Concerns:

• Following the rule of least invasive (and effective) to more invasive (and effective), a summary of treatment is as follows:

• All patients first should be offered nasal CPAP therapy.

• In patients with mild-to-severe OSA who refuse or reject nasal CPAP therapy, bilevel positive airway pressure should be tried next. If this therapy fails or is rejected/refused, then oral appliance therapy should be considered.

• Oral appliances may be considered first-line therapy for patients with mild OSA, particularly if they are unwilling to try nasal CPAP therapy.

• All interventions to improve tolerance of CPAP therapy should be attempted prior to deciding that treatment has failed in a particular patient.

• Patients in whom noninvasive medical therapy (eg, positive airway pressure, oral appliances) fails should be offered surgical options. Patients should be made aware of the success rates for each surgical procedure. They should be informed that they might require more than one surgical procedure (some fairly extensive) to cure OSA. Only refer patients to centers that have personnel experienced in these special surgical techniques.