Type I Polysomnography (PSG) is performed in a sleep lab, hospital, or other dedicated unit and supervised by a sleep technologist.  PSG includes measurements of oxygen saturation, electrocardiography (ECG), electroencephalography (EEG), electromyography (EMG), electrooculography (EOG), airflow, and respiratory effort measurements.  PSG's document sleep architecture, including rapid eye movement (REM)-related events, and quantify arousals, apneic episodes, oxygen desaturation, cardiac arrhythmias, limb movements, and seizure activity.  Home Portable Monitor (HPM) devices are also used to diagnose obstructive sleep apnea (OSA).  There are several different kinds of HPMs (Type II, III, and IV) which differ in the number of channels of information and types of measurements made. 

For information related to other technologies utilized in the treatment and management of sleep-related disorders, please see:

• MED.00002 Multiple Sleep Latency Testing (MSLT) and other Sleep Testing Services;
• SURG.00074 Nasal Surgery for the Treatment of Obstructive Sleep Apnea (OSA) and Snoring;
• SURG.00129 Oral, Pharyngeal and Maxillofacial Surgical Treatment for Obstructive Sleep Apnea;
• CG-DME-27 Bi-Level Positive Airway Pressure (BPAP) Respiratory Assist Devices;
• CG-DME-32 Continuous Positive Airway Pressure (CPAP) and Auto-titrating Positive Airway Pressure (APAP) Devices.

Section A: Home Portable Monitoring Devices

Medically Necessary:

The following Home Portable Monitoring (HPM) devices are considered medically necessary when used for a medically necessary purpose according to the criteria in Section B below:

• Type II HPM devices; and
• Type III HPM devices with a minimum of 4 parameters, including ventilation or airflow (at least 2 channels of respiratory movement, or respiratory movement and airflow), heart rate or ECG, and oxygen saturation.  

Not Medically Necessary:

The following HPM devices are considered not medically necessary for all indications:

• Type III HPM devices which do not meet medical necessity criteria above; and
• Type IV HPM devices. 

Note:  Use of the term "HPM" in the clinical indications section of this document, except where specifically indicated, refers to medically necessary HPM devices that satisfy the criteria in this section A.

Section B: Evaluation of Obstructive Sleep Apnea and Upper Airways Resistance Syndrome using PSG and HPM

Medically Necessary: 

HPM devices which meet the medical necessity criteria in Section A above, or PSG, are considered medically necessary in the evaluation of suspected obstructive sleep apnea (OSA) or upper airways resistance syndrome (UARS) when the criteria specified in subsections 1) AND 2) below are met:

1. For HPM and PSG, one or more of the following clinical indications are present:
   1. Witnessed apnea during sleep greater than 10 seconds in duration; OR
   2. Any combination of two or more of the following symptoms of OSA {i. through v.}:
      1. Excessive daytime sleepiness as evidenced by:
         1. inappropriate daytime napping (e.g., during driving, conversation, or eating); or
         2. sleepiness that interferes with daily activities when not explained by other conditions, such as poor sleep hygiene, medication, drugs, alcohol, psychiatric or psychological disorders, or
         3. an Epworth Sleepiness Scale score greater than 10;  or
      2. Persistent or frequent socially disruptive snoring or choking or gasping episodes associated with awakenings;  or
      3. Obesity (BMI greater than or equal to 30 kg/m²); or
      4. Unexplained hypertension; or
      5. Craniofacial or upper airway soft tissue abnormalities. 
         AND
2. For HPM devices only, all the criteria in a), b), and c) below are met:
   1. The individual is an adult; and
   2. There is no suspicion of other sleep disorder (e.g., narcolepsy, central sleep apnea, or periodic limb movement disorder);  and
   3. There is no evidence of a significant medical comorbidity (e.g., CHF, chronic pulmonary disease, or neuromuscular disease), except when testing by PSG is either not feasible or the individual is unable to tolerate the PSG (note:  this exception applies to the comorbidity requirement only).

Split-Night PSG for adults is considered medically necessary when the apnea hypopnea index (AHI) or respiratory disturbance index (RDI) is expected to be greater than or equal to 20 per hour based on at least 2 hours of PSG study.

Repeat PSG or HPM is considered medically necessary under any of the following circumstances:

• To re-evaluate an individual with failure of resolution of symptoms or recurrence of symptoms during treatment; OR
• To evaluate the impact of uvulopalatopharyngoplasty (UPPP) or other corrective surgeries for OSA after appropriate recovery from surgery; OR
• To evaluate the impact of an oral appliance when the Apnea-Hypopnea Index (AHI) or Respiratory Disturbance Index (RDI) was greater than15 pre-treatment; OR
• To titrate continuous positive airway pressure (CPAP) following an initial PSG where OSA was demonstrated and a split night study was not feasible; OR
• To reevaluate the diagnosis of OSA and need for continued CPAP in a person previously diagnosed by PSG and currently using CPAP, if a significant weight loss has occurred since the initial study; OR
• To titrate CPAP prescription when half night or "split night" PSG with titration of CPAP performed in the second part of the study is not possible due to AHI or RDI less than 20 per hour or when initial PSG was not diagnostic in time to allow for at least 3 hours of CPAP titration including both REM and non-REM sleep. 

Not Medically Necessary:

PSG or HPM is considered not medically necessary for the evaluation of suspected OSA or UARS when criteria above are not met.

A split-night PSG (to titrate CPAP in the second half of the study) is considered not medically necessary when the criteria above are not met.

Repeat PSG or HPM is considered not medically necessary when the criteria above are not met.

Repeat PSG or HPM is considered not medically necessary in the follow-up of individuals with OSA treated with CPAP when symptoms attributable to OSA have resolved. 

PSG or HPM is considered not medically necessary for the following symptoms or conditions existing alone in the absence of other features suggestive of OSA:

• Snoring; 
• Obesity; 
• Hypertension; 
• Morning headaches; 
• Decrease in intellectual functions; 
• Memory loss; 
• Frequent nighttime awakenings; 
• Other sleep disturbances, such as insomnia (acute or chronic), night terrors, sleep walking, epilepsy where nocturnal seizures are not suspected;
• Common uncomplicated non-injurious parasomnias.

Section C: Additional Indications for PSG 

Medically Necessary: 

PSG  is considered medically necessary in individuals with any of the following clinical presentations:

1. Sleep paralysis, hypnagogic hallucinations, cataplexy or other symptoms suggestive of Narcolepsy;  OR
2. Unusual/atypical parasomnias, such as sleep-related violent or injurious behavior, REM behavior disorder or suspected nocturnal seizures;  OR
3. Nocturnal oxygen desaturation with unexplained right heart failure, polycythemia, cardiac arrhythmias during sleep or pulmonary hypertension;  OR
4. Suspected periodic limb movements during sleep or suspected idiopathic hypersomnia, when excessive daytime sleepiness is demonstrated by any of the following:
   1. Inappropriate daytime napping (e.g., during driving, conversation, or eating), or
   2. Sleepiness that interferes with daily activities when not explained by other conditions, such as poor sleep hygiene, medication, drugs, alcohol, psychiatric or psychological disorders, or
   3. Epworth Sleepiness Scale score greater than 10. 

Not Medically Necessary: 

HPM devices are considered not medically necessary for diagnosis of conditions other than OSA or UARS.

Section D: Additional Indications for PSG in Children (Age less than 18) 

Medically Necessary:

PSG for children is considered medically necessary for the diagnosis of sleep disorders when one or more of the following indications are present:

1. Habitual snoring associated with one or more of the following (a. through e.):
   1. Restless or disturbed sleep; or
   2. Behavioral disturbance, or learning disorders including deterioration in academic performance, hyperactivity, or attention deficit disorder; or
   3. Enuresis; or
   4. Frequent awakenings; or
   5. Failure to thrive or growth impairment; OR
2. Witnessed apnea greater than 2 respiratory cycle times (inspiration and expiration); OR
3. Excessive daytime somnolence, or altered mental status unexplained by other conditions or etiologies; OR
4. Polycythemia unexplained by other conditions or etiologies; OR
5. Cor pulmonale unexplained by other conditions or etiologies; OR
6. Increased respiratory efforts, labored breathing, or sternal or intercostal retractions during sleep; OR
7. Hypertrophy of tonsils and adenoids associated with noisy daytime respirations where surgical removal poses a significant risk and would be avoided in the absence of sleep disordered breathing; OR
8. Suspected congenital central alveolar hypoventilation syndrome or sleep related hypoventilation due to neuromuscular disorders or chest wall deformities; OR
9. Clinical evidence of a sleep related breathing disorder in infants who have experienced an apparent life-threatening event.

Repeat PSG for children is considered medically necessary in the following circumstances:

• Initial PSG is inadequate or non-diagnostic and the accompanying caregiver reports that the child's sleep and breathing patterns during the testing were not representative of the child's sleep at home; OR
• A child with previously diagnosed and treated OSA who continues to exhibit persistent snoring or other symptoms of sleep disordered breathing. In the case of adenotonsillectomy, repeat PSG should also be performed if the pre-operative OSA was severe (RDI or AHI greater than 19 per hour). [If the treatment was surgical, testing should be deferred for 6 to 8 weeks post-operatively]; OR
• To periodically re-evaluate the appropriateness of CPAP settings based on the child's growth pattern or the presence of recurrent symptoms while on CPAP; OR
• If obesity was a major contributing factor and significant weight loss has been achieved, repeat testing may be indicated to determine the need for continued therapy.                                                                                                       

Not Medically Necessary:

Repeat PSG is considered not medically necessary in the follow-up of children with OSA treated with CPAP when symptoms attributable to sleep apnea have resolved. 

PSG for children is considered not medically necessary for the following:

• Sleep walking or night terrors;  or
• Routine evaluation of adenotonsillar hypertrophy alone without other clinical signs or symptoms suggestive of obstructive sleep disordered breathing;  or
• Routine follow-up for children whose symptoms have resolved post-adenotonsillectomy unless the pre-operative RDI or AHI was greater than 19 per hour or the child continues to snore post-operatively or other symptoms related to pre-operative sleep disordered breathing persist or recur. 

Split-night PSG for children is considered not medically necessary for all indications.

Section E: HPM in Children (Age less than 18)

Not Medically Necessary: 

HPM devices are considered not medically necessary for children for all indications including, but not limited to as an alternative to PSG.

The following codes for treatments and procedures applicable to this document are included below for informational purposes.  Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy.  Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member. 

Future ICD-10 coding (effective 10/01/2013)
A draft of ICD-10 Coding related to this document, as it might look today, is available for reference and comments at: Appendix 1: Future ICD-10 coding

Description of Sleep Disorders

Sleep disorders have a significant impact on quality of life, productivity, and health.  There are many different types of sleep-related disorders including obstructive sleep apnea (OSA), upper airway resistance syndrome (UARS), insomnia, narcolepsy, nocturnal movement disorders, such as Restless Leg Syndrome (RLS) and Periodic Limb Movement Disorder (PLMD), unexplained excessive daytime sleepiness, and arousal disorders (parasomnias). Most, if not all, of these sleep-related disorders are treatable once diagnosed.

Both PSG and HPM are used to diagnosis sleep disturbances.  These tests monitor various parameters, including heart and respiratory rate, body position and movement, to gain an understanding of the conditions under which sleep disturbances occur.  OSA occurs as the result of physical occlusion of the upper airway during sleep which interferes with normal breathing.  The occlusion is usually in the back of the tongue and/or flabby tissue in the upper airway.  This condition is associated with frequent awakening and often with daytime sleepiness.

Clinically significant OSA in adults, defined by an Apnea-Hypopnea Index (AHI) or Respiratory Disturbance Index (RDI) of at least 5 per hour associated with excessive daytime somnolence, is found in 4% of males and 2% of females in the 30 – 60 year old age group.  According to the American Academy of Sleep Medicine (AASM), definitions of OSA severity are provided as follows:

• Mild OSA: AHI of 5-15 per hour (Involuntary sleepiness during activities that require little attention, such as watching TV or reading);
• Moderate OSA: AHI of 15-30 per hour (Involuntary sleepiness during activities that require some attention, such as meetings or presentations);
• Severe OSA: AHI of more than 30 per hour (Involuntary sleepiness during activities that require more active attention, such as talking or driving).  (AASM, 2008)

Upper airway resistance syndrome (UARS) is a very similar but less severe sleep disorder than OSA and is also characterized by airway resistance to breathing during sleep. However, the parameters used to determine severity in OSA (AHI or RDI and oxygen saturation levels) are less severely affected in UARS than in OSA.  The primary symptoms of UARS include daytime sleepiness and excessive fatigue.  Untreated UARS can progress to the diagnosis of OSA. 

Description of Sleep Studies 

Standard PSG (also known as a Type I study) may be performed in a hospital, free-standing facility, or even in an office setting.  During the test, sensors monitor breathing, heart rate, and other measurements during a period of directly observed sleep.  Throughout the test, technicians record and monitor the readings received from the sensors.  Technicians may need to re-attach loosened sensors if any should need adjustment. 

• A Type I PSG sleep test includes continuous and simultaneous attended monitoring and recording the following seven parameters:
  1. 1-4 lead electroencephalogram (EEG);
  2. Electro-oculogram (EOG);
  3. Submental electromyogram (EMG);
  4. Electrocardiogram (ECG);
  5. Airflow;
  6. Respiratory effort;
  7. Oxygen saturation with pulse oximetry.

PSG's may be performed for diagnosis on one night and titration of continuous positive airway pressure (CPAP is a treatment of sleep apnea) on a subsequent night.  Alternatively, a split-night sleep study may be performed where the first half of the night is a standard Type I PSG study, and, if the study confirms OSA, the second half of the study is used for a CPAP evaluation and titration.

HPM devices have been categorized into Type II, Type III and Type IV test devices:  

• Type II HPM devices monitor and record a minimum of seven parameters: EEG, EOG, EMG, ECG/heart rate, airflow respiratory movement/effort, and oxygen saturation.  These portable test devices are essentially similar to Type I PSG devices except that Type II HPM devices are performed in the home and are generally unattended.
  
• Type III HPM devices monitor and record a minimum of four parameters: respiratory movement/effort, airflow, ECG/heart rate, and oxygen saturation.  These portable HPM test devices provide an assessment of cardiorespiratory parameters but do not provide data on sleep staging.
  
• Type IV HPM devices measure three or more channels, only one of which is airflow.

Type II HPM studies differ from standard Type I facility-based PSG in that a technician is not in attendance.  Type II HPM studies measure the same seven parameters as a Type I PSG study. 

HPM's may measure other parameters, in addition to those mentioned above.  Some measure peripheral arterial tone (PAT), an indirect measure of airflow and apnea.  Devices using PAT measurement often do not directly measure respiratory effort or airflow, for example, the WATCH-PAT^™ System (Itamar-Medical, Inc., Franklin, MA) which received FDA 510(k) clearance in November 2001 as a diagnostic aid for the detection of sleep related breathing disorders and sleep staging. It is worn on the wrist with finger-mounted probes that measure peripheral arterial tone, blood oxygen saturation and actigraphy based on wrist motion.  Signals captured by the recorder sensors are analyzed using automated computerized algorithms that calculate the frequency of respiratory events per hour of actigraphy-determined sleep. In 2009, the California Technology Assessment Forum (CTAF) determined that the WATCH-PAT device met its criteria for safety, effectiveness and improvement in health outcomes in patients at very high risk for OSA and unlikely to have another cause for their sleepiness.  The CTAF report findings were based, in large part, on two randomized trials (Berry, 2008; Townsend, 2007), both of which have significant methodological limitations in that they were small, single center studies with significant loss to follow-up and lack of evaluation for the most important outcomes associated with OSA (motor vehicle accidents, strokes, sudden death, myocardial infarctions). 

Other devices may record noises made during sleep, such as the SNAP^™ Test (SNAP Laboratories, Glenview, IL).  This system obtained FDA clearance through the 510(k) approval process.  Earlier models of this HPM device were a sound collection and airflow device whereby data is recorded during sleep and returned to the SNAP laboratory for analysis.  Later models (SNAP Models 6^™ and 7^™ Testing Systems) contain additional channels of data recording, (including 3 respiratory parameters [air flow, effort, and audio] and two additional channels that monitor oxygen saturation and pulse with an optional body position channel).  As such, these newer SNAP Models (6 and 7) meet the definition of a medically necessary Type III HPM device found in this policy.. 

Evaluation of Sleep Disorders using PSG and HPM 

PSG is used for diagnosis of sleep-related disorders, including, but not limited to, obstructive sleep apnea (OSA), narcolepsy, nocturnal myoclonia, and for titration of continuous positive airway pressure (CPAP).  HPM, on the other hand, are only used for the diagnosis of OSA in adults.

It may be difficult to determine which individuals are appropriate candidates for PSG or HPM.  Numerous models have been proposed to reliably suggest the presence of OSA in adults.  The American Academy of Sleep Medicine (AASM) states that, "Adult patients with habitual snoring, excessive daytime sleepiness, a BMI greater than or equal to 30 and observed apneas are at high risk for OSA with at least a 75% likelihood of having an AHI (or RDI) equal to or greater than 10."  Netzer, in a 1999 article in the Annals of Internal Medicine, used the "Berlin Questionnaire" with three groups of questions: one regarding snoring, the second regarding daytime sleepiness, and the third regarding the presence of hypertension or obesity.  They found that positive responses in two out of the three categories had a sensitivity of 86%, a specificity of 77%, and a positive predictive value of 89%.

PSG testing is not warranted for individuals with only a single clinical feature, such as snoring, hypertension or obesity in isolation.  Snoring alone is said to occur in up to 40% of the population, and this increases over the age of 50 years.  Performing PSG in individuals who snore but do not have other associated findings suggestive of sleep apnea is not recommended.

In 2009, a Clinical Guideline for the Evaluation, Management and Long-term Care of Obstructive Sleep Apnea in Adults was prepared by the Adult OSA Task Force of the AASM (Epstein, 2009).  This document provides specific information regarding PSG and HPM.  The following is excerpted from the AASM document specific to PSG and split-night testing:

Full-night PSG is recommended for the diagnosis of a sleep related breathing disorder but a split-night study (initial diagnostic PSG followed by continuous positive airway pressure titration on the same night) is an alternative to one full night of diagnostic PSG. The split-night study may be performed if an AHI ≥ 40/hr is documented during 2 hours of a diagnostic study but may be considered for an AHI of 20-40/hr based on clinical judgment. In patients where there is a strong suspicion of OSA, if other causes for symptoms have been excluded, a second diagnostic overnight PSG may be necessary to diagnose the disorder. The diagnosis of OSA is confirmed if the number of obstructive events (apneas, hypopneas + respiratory event related arousals) on PSG is greater than 15 events/hr or greater than 5/hour in a patient who reports associated symptoms… (Epstein, 2009).

Additional excerpted information from this AASM document is as follows:

A diagnosis of OSA must be established by an acceptable method (Standard).The two accepted methods of objective testing are in-laboratory polysomnography (PSG) and home testing with portable monitors (PM).  PMs may be used to diagnose OSA when utilized as part of a comprehensive sleep evaluation in patients with a high pretest likelihood of moderate to severe OSA (Consensus).

PM testing is not indicated in patients with major comorbid conditions including, but not limited to, moderate to severe pulmonary disease, neuromuscular disease, or congestive heart failure, or those suspected of having a comorbid sleep disorder (Consensus).

A PM should, at a minimum, record airflow, respiratory effort, and blood oxygenation. The type of biosensors used to monitor these parameters for in-laboratory PSG are recommended for use in PMs and include an oronasal thermal sensor to detect apneas, a nasal pressure transducer to measure hypopneas, oximetry, and, ideally, calibrated or uncalibrated inductance plethysmography for respiratory effort (Consensus).

The diagnosis of OSA is confirmed and severity determined using the same criteria as used for PSG… OSA severity is defined as mild for a Respiratory Disturbance Index (RDI) greater than or equal to 5 and less than 15, moderate for RDI greater than or equal to 15 and less than or equal to 30, and severe for RDI greater than 30/hr (Consensus).

The term RDI has been defined differently when used with PMs than when used with PSG. The RDI in PM is the number of apneas plus hypopneas/total recording time rather than total sleep time. As a result, PMs are likely to underestimate the severity of events compared to the Apnea/Hypopnea Index (AHI) by PSG. Due to the known rate of false negative PM tests, in-laboratory PSG should be performed in cases where PM is technically inadequate or fails to establish the diagnosis of OSA in patients with a high pretest probability (Consensus).  (Epstein, 2009)

A 2007 technology assessment performed for the Centers for Medicare and Medicaid Services (CMS) by the Agency for Healthcare Research and Quality (AHRQ) addressed HPM testing compared to PSG for diagnosing OSA in adults (Trikalinos, 2007). The AHRQ report concluded that, based on limited data, Type III HPM devices have a high positive likelihood ratio and low negative likelihood ratio for identifying an AHI suggestive of OSA. Also, for individuals with a high probability of OSA, the use of PSG does not result in better outcomes over an ambulatory approach to diagnosis and CPAP titration. The increased accuracy of PSG does not translate into more accurate predictions of the response to CPAP based on quality of life outcome measures. However, the assessment makes several statements that suggest that Type III HPM devices are less accurate than PSG, particularly when performed in the home setting, and states there may be substantial differences in the AHI compared to PSG. Unsatisfactory studies were more common in the home, and this AHRQ report noted, "…Inadequate or missing data precluding adequate interpretation was reported in 13%-20%c of studies for Type III test devices."

In 2011, another AHRQ report was issued entitled, Diagnosis and Treatment of Obstructive Sleep Apnea in Adults. Comparative Effectiveness Review.  This comparison of HPM devices and PSG provided the following:

HPM accurately predict elevated AHI suggestive of OSA (but cannot estimate exact AHI values as measured by sleep-laboratory PSG/Type I monitors):

††Type II HPM monitors. Strength of Evidence is low; (There are very few studies, or existing studies are flawed.)

††Type III and IV HPM monitors. Strength of Evidence is moderate; (Findings are supported, but further research could change the conclusions.)

††There is insufficient evidence to compare the types of at-home monitors. Strength of Evidence is insufficient. (Research is either unavailable or does not permit estimation of a treatment effect.)

• The strength of evidence is moderate that Type III and IV HPM monitors are generally accurate to diagnose OSA (as defined by PSG), but have a wide and variable bias in estimating the actual AHI. The evidence is insufficient to adequately compare specific monitors to each other. 
• The strength of evidence is low that Type II HPM monitors are accurate to diagnose OSA (as defined by PSG), but have a wide and variable bias in estimating the actual AHI.

This document concluded:

The more recent studies do not substantially change the conclusions from the Tufts Evidence-based Practice Center's 2007 Technology Assessment on Home Diagnosis of Obstructive Sleep Apnea-Hypopnea Syndrome. Although most of the tested portable monitors fairly accurately predict OSA, it is unclear whether any of these monitors can replace laboratory based PSG. The evidence suggests that the measured AHI from portable monitors is variable compared with PSG-derived AHI, but the source of this variability is unclear. So far, no studies have evaluated the predictive ability for clinical outcomes or response to treatment by portable monitors (Balk, 2011).

In general, there is a preponderance of literature suggesting that Type III HPM devices can be used to "rule in" OSA in individuals with a high pre-test probability of moderate to severe OSA. However, high probability individuals with negative or indeterminate Type III HPM results would then require a diagnostic, Type I attended, facility-based PSG to "rule out" a clinically significant sleep disorder.

In 2008, the AASM published another guidance document entitled, Clinical Guideline for the Evaluation and Management of Chronic Insomnia in Adults (Schutte-Rodin, 2008), in which the following comments were made:

Polysomnography and daytime multiple sleep latency testing (MSLT) are not indicated in the routine evaluation of chronic insomnia, including insomnia due to psychiatric or neuropsychiatric disorders.

Polysomnography is indicated when there is reasonable clinical suspicion of breathing (sleep apnea) or movement disorders, when initial diagnosis is uncertain, treatment fails (behavioral or pharmacologic), or precipitous arousals occur with violent or injurious behavior (AASM, 2008).

The above document updates the former AASM guidance (Kushida, 2005) which had determined that PSG is not indicated for the routine evaluation of transient insomnia, chronic insomnia, or insomnia associated with psychiatric disorders (AASM, 2005). 

PSG and HPM Testing in Children 

OSA occurs in approximately 2% of children at a peak of 2 to 6 years of age (habitual snoring occurs in 3% to 12% of preschool age children).  Most children with OSA will have habitual snoring, and this may be accompanied by labored breathing or restlessness during sleep.  Daytime manifestations of OSA in children are more subtle and may be more diverse than in adults.  Symptoms may include behavioral problems and neuro-cognitive dysfunction with a nearly three-fold increase in children with OSA.  Although the precise relationship between OSA and attention deficit hyperactivity disorder (ADHD) is unknown, it appears that the presence of OSA may exacerbate ADHD, and that some children with hyperactivity caused by OSA may be misdiagnosed as having ADHD.  The possible relationship is strengthened by the observation that children with ADHD have high rates of sleep complaints and disturbances.  It is recommended that children who snore and carry a diagnosis of ADHD should be evaluated for the possibility that OSA is causing or exacerbating the behavioral symptoms.  While excessive daytime sleepiness may be present in approximately 20% of children with OSA, this symptom occurs less frequently than in adults.

Although OSA in children is commonly related to the presence of adenotonsillar hypertrophy, other factors related to dynamic airway collapse appear to be involved.  In otherwise normal children with OSA, it is felt that adenotonsillar hypertrophy causes airway narrowing that, when superimposed on subtle abnormalities of upper airway motor control or tone, leads to clinically significant dynamic airway obstruction during sleep.  However, the adenotonsillar size or volume, in and of itself, has not been shown to have a simple relationship with the presence of OSA in children.  Routine PSG in children with adenotonsillar hypertrophy, in the absence of other signs or symptoms suggestive of OSA, is not recommended.  By the same token, routine PSG post-adenotonsillectomy, in a child with pre-existing mild to moderate OSA whose symptoms have resolved post-operatively, is not recommended.  However, follow-up PSG is recommended post-operatively in the case of a child with pre-existing severe OSA (RDI or AHI greater than 19 per hour).

Other factors that may place the child at risk for OSA include: neuromuscular disease associated with either hypotonia or hypertonia; genetic syndromes associated with craniofacial abnormalities, such as midface hypoplasia, micrognathia or small nasopharynx; narrow high arched hard palate, long soft palate, or shallow pharyngeal area; prematurity or African-American ethnicity (in certain age groups).

The diagnosis of OSA in children is definitively established by performing overnight PSG in a sleep lab setting.  However, what constitutes normal or abnormal respiratory events during sleep, and the clinical significance and/or implications of these, are not as well established or defined as in the adult population.  The natural history of childhood OSA is not well understood, and the mortality rate in childhood OSA is unknown.  It should also be noted that normative PSG data in children differs from that in adults. 

Regarding pediatric applications for testing, the 2009 AASM guidance document specifies that its recommendations regarding HPM testing are directed at adults only, due to the lack of data on the use of HPM in the pediatric population (Epstein, 2009).  The 2002 Clinical Practice Guidelines entitled, Diagnosis and Management of Childhood Obstructive Sleep Apnea Syndrome from the American Academy of Pediatrics (AAP, 2002) state the following:  "Although we know which polysomnographic parameters are statistically abnormal, studies have not definitively evaluated which polysomnographic criteria predict morbidity."  Nevertheless, most children in whom a diagnosis is made will undergo adenotonsillectomy which will be corrective in 75% - 100% of cases.  This AAP document has not been updated since 2002.

In 2011, the AASM issued a new guideline entitled, Practice Parameters for the Respiratory Indications for Polysomnography in Children in which several recommendations and accompanying evidence ratings were made for use of PSG in children with respiratory conditions which align with the current indications in this document.  However, two additional recommendations were noted which are based on review of published evidence at the level of: "Guideline, (i.e., This is a patient-care strategy that reflects a moderate degree of clinical certainty and implies the use of Level 2 evidence or a consensus of Level 3 evidence)."  These recommendations have been added to the indications considered medically necessary for children as follows:

• PSG is indicated when the clinical assessment suggests the diagnosis of congenital central alveolar hypoventilation syndrome or sleep related hypoventilation due to neuromuscular disorders or chest wall deformities. It is indicated in selected cases of primary sleep apnea of infancy.
• PSG is indicated when there is clinical evidence of a sleep related breathing disorder in infants who have experienced an apparent life-threatening event (Aurora, 2011).

In 2011, the American Academy of Otolaryngology-Head and Neck Surgery (AAOHNS) issued a Clinical Practice Guideline entitled, Polysomnography for Sleep-Disordered Breathing Prior to Tonsillectomy in Children.  This document made several recommendations, however, those recommendations were based on low levels of evidence (Grade C: Observational studies (case control and cohort design)) and are not accepted for use in this document (Roland, 2011).

Another 2008 AASM guidance document entitled, Clinical Guidelines for the Manual Titration of Positive Airway Pressure in Patients with Obstructive Sleep Apnea (Kushida, 2008) applies to both adults and children, "The scope of these PAP titration recommendations is restricted to adult (≥ 12 years) and pediatric (< 12 years) patients with obstructive sleep apnea; these recommendations do not apply to patients with conditions, such as neuromuscular disease or intrinsic lung disease."  This document also states that there is no scientific basis to make any recommendations for performing split-night PSG in children less than 12 years of age (AASM, 2008).

The Epworth Sleepiness Scale 

One of the criteria for obtaining a sleep study is abnormal daytime sleepiness.  This is usually measured using a widely used tool called the Epworth Sleepiness scale (ESS).  An ESS score of greater than or equal to 21 is considered excessive daytime sleepiness, but in clinical practice a score of greater than 10 is considered abnormal and requiring medical attention.

The following scale is used to rate answers to the questions below:
0 = No chance of dozing, 1 = Slight chance of dozing, 2 = Moderate chance of dozing, 3 = High chance of dozing

_____ Sitting and reading;
_____ Watching TV;
_____ Sitting inactive in a public place (theater or a meeting);
_____ As a passenger in a car for an hour without a break;
_____ Lying down to rest in the afternoon when circumstances permit;
_____ Sitting and talking to someone;
_____ Sitting quietly after a lunch without alcohol;
_____ In a car, while stopped for a few minutes in traffic;
_____ Total Score.

The following scale is used to interpret the Total Score Level of Daytime Sleepiness:

0 - 7    Normal sleep function;
8 - 10  Mild daytime sleepiness;
11- 15 Moderate daytime sleepiness;
16- 20 Severe daytime sleepiness;
21- 24 Excessive daytime sleepiness.

Adults: 

Peer Reviewed Publications:

1. Ayas NT, Pittman S, MacDonald M, White DP.  Assessment of a wrist-worn device in the detection of obstructive sleep apnea.  Sleep Med. 2003; 4(5):435-442.
2. Bar A, Pillar G, Dvir I, et al. Evaluation of a portable device based on peripheral arterial tone for unattended home sleep studies. Chest. 2003; 123(3):695-703.
3. Berry RB, Hill G, Thompson L, McLaurin V.  Portable monitoring and autotitration versus polysomnography for the diagnosis and treatment of sleep apnea.  Sleep. 2008; 31(10):1423-1431.
4. Bruyneel M, Sanida C, Art G, et al.  Sleep efficiency during sleep studies: results of a prospective study comparing home-based and in-hospital polysomnography.  J Sleep Res. 2011; 20(1 Pt 2):201-206.
5. Campbell AJ, Neill AM.  Home set-up polysomnography in the assessment of suspected obstructive sleep apnea.  J Sleep Res. 2011; 20(1 Pt 2):207-213.
6. Chesson AL Jr., Ferber RA, Fry JM, et al. The indications for polysomnography and related procedures. Sleep. 1997; 20(6):423-487.
7. Flemons WW. Clinical practice. Obstructive sleep apnea, N Engl J Med. 2002; 347(7):498-504.
8. Fletcher EC, Stich J, Yang KL. Unattended home diagnosis and treatment of obstructive sleep apnea without polysomnography. Arch Fam Med. 2000; 9(2):168-174.
9. Fry JM, DiPhilipo MA, Curran K, et al.  Full polysomnography in the home.  Sleep. 1998; 21(6):635-642.
10. Guilleminault C, Abad VC. Obstructive sleep apnea syndromes. Med Clin North Am. 2004; 88(3):611-630.
11. Gagnadoux F, Pelletier-Fleury N, Philippe C, et al. Home unattended vs. hospital telemonitored polysomnography in suspected obstructive sleep apnea syndrome: a randomized crossover trial. Chest. 2002; 121(3):753-758.
12. Iber C, Redline S, Kaplan Gilpin AM, et al. Polysomnography performed in the unattended home versus the attended laboratory setting--Sleep Heart Health Study Methodology. Sleep. 2004; 27(3):536-540.
13. Khawaja IS, Olson EJ, van der Walt C, et al. Diagnostic accuracy of split-night polysomnograms. J Clin Sleep Med. 2010;  6(4):357-362.
14. Kuna ST. Portable-monitor testing: an alternative strategy for managing patients with obstructive sleep apnea. Respir Care. 2010; 55 (9):1196-1215. Available at: http://www.rcjournal.com/contents/09.10/09.10.1196.pdf. Accessed on September 5, 2011.
15. Kushida CA. A predictive morphometric model for the obstructive sleep apnea syndrome.  Ann Int Med. 1997; 127(8)Pt1:581-587.
16. Levendowski D, Steward D, Woodson BT, et al. The impact of obstructive sleep apnea variability measured in-lab versus in-home on sample size calculations. Int Arch Med. 2009; 2 (1):2.
17. Liesching TN, Carlisle C, Marte A, et al.  Evaluation of the accuracy of SNAP technology sleep sonography in detecting obstructive sleep apnea in adults compared to standard polysomnography. Chest. 2004; 125(3):886-891.
18. Michaelson PG, Allan P, Chaney J, Mair EA. Validations of a portable home sleep study with twelve-lead polysomnography: comparisons and insights into a variable gold standard. Ann Otol Rhinol Laryngol. 2006; 115(11):802-809.
19. Millman RP.  Full polysomnography in the home: has it come of age?  Chest. 1999; 115(1):6-7.
20. Netzer NC, Stoohs RA, Netzer CM, et al. Using the Berlin Questionnaire to identify patients at risk for the sleep apnea syndrome. Ann Intern Med. 1999; 131(7):485-491.
21. Pang KP, Gourin CG, Terris DJ. A comparison of polysomnography and the Watch PAT in the diagnosis of obstructive sleep apnea.  Otolaryngol Head Neck Surg. 2007; 137(4):665-668.
22. Pillar G, Bar A, Shlitner A, et al.  Autonomic arousal index: an automated detection based on peripheral arterial tonometry.  Sleep. 2002; 25(5):541-547.
23. Pittman SD, Ayas NT, MacDonald MM, et al.  Using a wrist-worn device based on peripheral arterial tonometry to diagnose obstructive sleep apnea: in-laboratory and ambulatory validation. Sleep. 2004; 27(5):923-933.
24. Rodway GW, Sanders MH. The efficacy of split-night sleep studies. Sleep Med Rev. 2003; 7(5):391-401. 
25. Series F. Accuracy of an unattended home CPAP titration in the treatment of obstructive sleep apnea. Am J Respir Crit Care Med. 2000; 162(1):94-97.
26. Strollo PJ Jr. Indications for treatment of obstructive sleep apnea in adults. Clin Chest Med. 2003, 24(2):307-313.
27. Su S, Baroody FA, Kohrman M, Suskind D. A comparison of polysomnography and a portable home sleep study in the diagnosis of obstructive sleep apnea syndrome. Otolaryngol Head Neck Surg. 2004; 131(6); 844-850.
28. Townsend D, Sharma A, Brauer E, et al.  Assessing efficacy, outcomes and cost savings for patients with obstructive sleep apnea using two diagnostic and treatment strategies.  Sleep Diag Ther. 2007; 1:1-8.
29. Watanabe T, Kumano-Go T, Suganuma N, et al.  The relationship between esophageal pressure and apnea hypopnea index in obstructive sleep apnea-hypopnea syndrome.  Sleep Res Online. 2000; 3(4):169-172.
30. Yamashiro Y, Kryger MH. CPAP titration for sleep apnea using a split night protocol.  Chest. 1995, 107(1):62-66.
31. Young T, Skatrud J, Peppard PE. Risk factors for obstructive sleep apnea in adults. JAMA. 2004; 291(16):2013-2016.
32. Zou D, Grote L, Peker Y, et al. Validation of a portable monitoring device for sleep apnea diagnosis in a population based cohort using synchronized home polysomnography.  Sleep. 2006; 29(3):367-374.

Government Agency, Medical Society, and Other Authoritative Publications:

1. Agency for Healthcare Policy and Research (AHCPR). Systematic review of the literature regarding the diagnosis of sleep apnea. Evidence Report/Technology Assessment No. 1. AHCPR Publication No. 99-E002. Bethesda, MD: AHCPR; December 1998.  Current as of January 2005.  Available at:  http://www.ahrq.gov/clinic/epcsums/apneasum.htm.  Accessed on September 6, 2011.
2. American Academy of Sleep Medicine (AASM). Obstructive Sleep Apnea. 2008. Available at: http://www.aasmnet.org/Resources/FactSheets/SleepApnea.pdf.  Accessed on September 6, 2011.
3. American Academy of Sleep Medicine (AASM). Standards for Accreditation of Out of Center Sleep Testing (OCST) in Adult Patients. 2011.  Available at:  http://www.aasmnet.org/ocststandards.aspx.  Accessed on September 6, 2011.
4. American Academy of Sleep Medicine. Practice parameters for the use of portable monitoring devices in the investigation of suspected obstructive sleep apnea in adults.  Sleep. 2003; 26(7):907-913.
5. American Sleep Disorders Association, Standards of Practice Committee. Practice parameter for the use of portable recording of the assessment of obstructive sleep apnea. Sleep. 1994; 17(4):372-377.
6. Balk EM, Moorthy D, Obadan NO, et al.  Diagnosis and Treatment of Obstructive Sleep Apnea in Adults.  Comparative Effectiveness Review No. 32. (Prepared by Tufts Evidence-based Practice Center under Contract No. 290-2007-100551). AHRQ Publication No. 11-EHC052-EF. Rockville, MD: Agency for Healthcare Research and Quality. July 2011. Available at:  www.effectivehealthcare.ahrq.gov/reports/final.cfm.  Accessed on September 6, 2011.
7. Blue Cross and Blue Shield Assoc. Technology Evaluation Center (TEC) assessments. Portable sleep studies for the diagnosis of obstructive sleep apnea syndrome. 1996; 11(2).
8. Canadian Agency for Drugs and Technologies in Health (CADTH).  Portable Monitoring Devices for Diagnosis of Obstructive Sleep Apnea at Home: Review of Accuracy, Cost-Effectiveness, Guidelines, and Coverage in Canada.  December 2009.  Available at:  http://www.cadth.ca/media/pdf/M0002_Portable_Monitoring_Devices_Obstructive_Sleep_Apnea_L3_e.pdf.  Accessed on September 6, 2011.
9. Centers for Medicare & Medicaid Services. CMS Manual System. Pub 100-3, manual section 240.4.1. Medicare National Coverage Determination. Sleep testing for obstructive sleep apnea (OSA). Effective March 3, 2009. Available at: http://www.cms.gov/medicare-coverage-database/details/ncd-details.aspx?NCDId=330&ncdver=1&DocID=240.4.1&bc=gAAAAAgAAAAA&. Accessed on September 6, 2011.
10. Centers for Medicare and Medicaid Services. National Coverage Determination: Continuous Positive Airway Pressure (CPAP) Therapy for Obstructive Sleep Apnea (OSA). NCD #240.4. Effective March 13, 2008. Available at: http://www.cms.gov/medicare-coverage-database/details/ncd-details.aspx?NCDId=226&ncdver=3&DocID=240.4&bc=gAAAAAgAAAAA&. Accessed on September 6, 2011.
11. Chesson AL Jr, Berry RB, Pack A; American Academy of Sleep Medicine; American Thoracic Society; American College of Chest Physicians. Practice parameters for the use of portable monitoring devices in the investigation of suspected obstructive sleep apnea in adults. Sleep. 2003; 26(7):907-913.Collop NA, Anderson WM, Boehlecke B, et al. Portable Monitoring Task Force of the American Academy of Sleep Medicine. Clinical guidelines for the use of unattended portable monitors in the diagnosis of obstructive sleep apnea in adult patients. J Clin Sleep Med. 2007; 3(7):737-747. Available at: http://www.aasmnet.org/jcsm/AcceptedPapers/PMProof.pdf.  Accessed on September 6, 2011.
12. Epstein LJ, Kristo D, Strollo PJ, et al. Clinical guideline for the evaluation, management and long-term care of obstructive sleep apnea in adults. J Clin Sleep Med. 2009; 5(3):263-276.  Available at:  http://www.aasmnet.org/Resources/ClinicalGuidelines/OSA_Adults.pdf.  Accessed on September 6, 2011.
13. Flemons WW, Littner MR, Rowley JA, et al.  Home diagnosis of sleep apnea: a systematic review of the literature. An evidence review cosponsored by the American Academy of Sleep Medicine, the American College of Chest Physicians, and the American Thoracic Society. Chest. 2003; 124(4):1543-1579.
14. Gay P, Weaver T, Loube D, Iber C.  Evaluation of Positive Airway Pressure Treatment for Sleep Related Breathing Disorders in Adults.  A Review by the Positive Airway Pressure Task Force of the Standards of Practice Committee of the American Academy of Sleep Medicine (AASM).  Sleep. 2006; 29(3):381-401.  Available at:  http://www.aasmnet.org/Resources/PracticeParameters/Review_PositiveAirwayPressure.pdf.  Accessed on September 6, 2011.
15. Hailey D, Tran K, Dales R, et al. A review of guidelines for referral of patients to sleep laboratories. Technology Report. Issue 55. Ottawa, ON: Canadian Coordinating Office for Health Technology Assessment (CCOHTA); 2005. Available at: http://www.cadth.ca/index.php/en/publication/519.  Accessed on September 6, 2011.
16. Iber C, Ancoli-Israel S, Chesson AL, Quan SF. The AASM manual for the scoring of sleep and associated events: rules, terminology and technical specifications. Westchester, IL: American Academy of Sleep Medicine; 2007.
17. Kushida CA, Chediak A, Berry RB, et al. Positive Airway Pressure Titration Task Force of the American Academy of Sleep Medicine. Clinical guidelines for the manual titration of positive airway pressure in patients with obstructive sleep apnea. J Clin Sleep Med. 2008; 4(2):157-171.  http://www.aasmnet.org/Resources/ClinicalGuidelines/040210.pdf.  Accessed on September 6, 2011.
18. Kushida CA, Littner MR, Morgenthaler T, et al.  Practice Parameters for the Indications for Polysomnography and Related Procedures:  An update for 2005.  American Academy of Sleep Medicine.  Sleep. 2005; 28(4):499-521.  Available at:  http://www.aasmnet.org/Resources/PracticeParameters/PP_Polysomnography.pdf  Accessed on September 6, 2011.
19. Littner M, Hirshkowitz M, Kramer M, et al. Practice parameters for using polysomnography to evaluate insomnia: an update. Sleep. 2003 26(6):754-760.
20. Morgenthaler TI, Aurora RN, Brown T, et al. Standards of Practice Committee of the American Academy of Sleep Medicine (AASM).  Practice parameters for the use of autotitrating continuous positive airway pressure devices for titrating pressures and treating adult patients with obstructive sleep apnea syndrome: an update for 2007. An American Academy of Sleep Medicine Report. Sleep. 2008; 31(1):141-147. Available at: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2225554/pdf/aasm.31.1.141.pdf.  Accessed on September 6, 2011.
21. Schutte-Rodin S, Broch L, Buysse D, et al. Clinical guideline for the evaluation and management of chronic insomnia in adults. J Clin Sleep Med. 2008; 4(5):487-504.  Available at:  http://www.aasmnet.org/Resources/ClinicalGuidelines/040515.pdf.  Accessed on September 6, 2011.
22. Tice JA.  California Technology Assessment Forum (CTAF).  Portable Devices used for Home Testing in Obstructive Sleep.  March 11, 2009.  Available at:  http://www.ctaf.org/content/assessment/detail/1038. Accessed on September 6, 2011.
23. Trikalinos TA, Ip S, Raman G, et al. Home diagnosis of obstructive sleep apnea-hypopnea syndrome. AHRQ Technology Assessment Program. Agency for Healthcare Research and Quality (AHRQ), Rockville, MD; August 8, 2007. Available at: http://www.cms.hhs.gov/determinationprocess/downloads/id48TA.pdf.  Accessed on September 6, 2011.
24. U.S. Department of Health and Human Services, National Institutes of Health (NIH), National Heart, Lung and Blood Institute (NHLBI). Sleep apnea: Is your patient at risk? NIH Pub. No. 95-3803. Bethesda, MD: NIH; September 1995. Available at: http://www.nhlbi.nih.gov/health/prof/sleep/slpaprsk.pdf.  Accessed on September 6, 2011.
25. U.S. Food and Drug Administration 510(k) Premarket Notification Database.  Summary of Safety and Effectiveness. SNAP Model 6^™ Testing System.  No. K002095. Rockville, MD: FDA. March 2, 2001. Available at:   http://www.accessdata.fda.gov/cdrh_docs/pdf/K002095.pdf.  Accessed on September 5, 2011.
26. U.S. Food and Drug Administration 510(k) Premarket Notification Database.  SNAP Model 7™ Testing System.  No. K080321. Rockville, MD: FDA. May 23, 2008. Available at: http://www.accessdata.fda.gov/cdrh_docs/pdf8/K080321.pdf.   Accessed on September 5, 2011.
27. U.S. Food and Drug Administration 510(k) Premarket Notification Database.  WATCH-PAT™ 200S-2 (Itamar-Medical Inc., Franklin, MA) No.  K081982. Rockville, MD: FDA. August 14, 2008. Available at: http://www.accessdata.fda.gov/cdrh_docs/pdf8/K081982.pdf.  Accessed on September 3, 2011.

Children: 

Peer Reviewed Publications:

1. Bass JL, Corwin M, Gozal D, et al.  The effect of chronic or intermittent hypoxia on cognition in childhood:  a review of the evidence.  Pediatrics. 2004; 114(3):805-816.
2. Carroll JL. Obstructive sleep-disordered breathing in children: new controversies, new directions. Clin Chest Med. 2003; 24(2):261-282.
3. D'Andrea LA. Diagnostic studies in the assessment of pediatric sleep-disordered breathing: techniques and indications. Pediatr Clin North Am. 2004; 51(1):169-186.
4. Goldstein NA, Pugazhendhi V, Rao SM, et al.  Clinical assessment of pediatric obstructive sleep apnea.  Pediatrics. 2004; 114:33-43.  Available at:  http://pediatrics.aappublications.org/content/114/1/33.full.pdf.  Accessed on September 6, 2011.
5. Gozal D, Kheirandish-Gozal L. Obesity and excessive daytime sleepiness in prepubertal children with obstructive sleep apnea.  Pediatrics. 2009; 123:13–18.  Available at:  http://pediatrics.aappublications.org/content/123/1/13.full.pdf.  Accessed on September 6, 2011.
6. Gozal D, Wang M, Pope DW Jr. Objective sleepiness measures in pediatric obstructive sleep apnea. Pediatrics. 2001; 108(3):613-617.
7. Hatzakis GE, Karsan N, Cook J, et al.  Acoustic reflectance of pharyngeal structures in children.  Int J Pediatr Otorhinolaryngol. 2003; 67(4):373-381.
8. 8.   Kotagal S. Sleep disorders in childhood. Neurol Clin. 2003; 21(4):961-981.7. Marcus CL, et al. Respiratory sleep studies in children. Establishment of normative data and polysomnographic predictors of morbidity. Am J Resp Crit Care Med. 1999, 160:1381-1387. 
9. Melendres CS, Lutz JM, Rubin ED, Marcus CL.  Daytime sleepiness and hyperactivity in children with suspected sleep-disordered breathing.  Pediatrics. 2004; 114:768-775.
10. O'Brien LM, Holbrook CR, Mervis CB, et al.  Sleep and neurobehavioral characteristics of 5- to 7-year old children with parentally reported symptoms of attention-deficit/hyperactivity disorder.  Pediatrics. 2003; 111(3):554-563.
11. Owens J, Opipari L, Nobile C, Spirito A.  Sleep and daytime behavior in children with obstructive sleep apnea and behavioral sleep disorders.  Pediatrics. 1998; 102(5):1178-1184.
12. Ray RM, Bower CM.  Pediatric obstructive sleep apnea: the year in review. Curr Opin Otolaryngol Head Neck Surg. 2005; 13(6):360-365.
13. Rosen CL. Obstructive sleep apnea syndrome in children: controversies in diagnosis and treatment. Pediatr Clin North Am. 2004; 51(1):153-167.
14. Sterni LM, Tunkel DE.  Obstructive sleep apnea in children: an update. Pediatr Clin North Am. 2003; 50(2):427-443.

Government Agency, Medical Society, and Other Authoritative Publications:

1. American Thoracic Society (ATS). Standards and indications for cardiopulmonary sleep studies in children.  Am J Respir Crit Care Med. 1996; 153(2):866-878.
2. American Academy of Pediatrics (AAP). Clinical practice guideline: Diagnosis and management of childhood obstructive sleep apnea syndrome. Pediatrics. 2002; 109(4):704-712. Available at: http://pediatrics.aappublications.org/cgi/content/full/109/4/704.  Accessed on September 6, 2011.
3. Aurora RN, Zak RS, Karippot A, et al.  American Academy of Sleep Medicine (AASM).  Practice parameters for the respiratory indications for polysomnography in children.  Sleep. 2011; 34(3):398A-398AW.  Available at:  http://guideline.gov/content.aspx?f=rss&id=33568.  Accessed on September 12, 2011.
4. Marcus CL. Obstructive sleep apnea syndrome: differences between children and adults. Sleep. 2000; 23(4 Suppl):S140-S141.
5. Marcus CL, Chapman D, Ward SD, et al. American Academy of Pediatrics. Clinical Practice Guideline: Diagnosis and management of childhood obstructive sleep apnea syndrome. Pediatrics. 2002, 109(4):704-712.  Available at:  http://aappolicy.aappublications.org/cgi/reprint/pediatrics;109/4/704.pdf.  Accessed on September 30, 2011.
6. Marcus CL, England A, Annett RD, et al. Cardiorespiratory sleep studies in children. Establishment of normative data and polysomnographic predictors of morbidity. Am J Respir Crit Care Med. 1999; 160(4):1381-1387.
7. Roland PS, Rosenfeld RM, Brooks LJ, et al.  American Academy of Otolaryngology- Head and Neck Surgery (AAOHNS).  Clinical Practice Guideline: Polysomnography for Sleep-Disordered Breathing Prior to Tonsillectomy in Children. Published online ahead of print: June 15, 2011.  Available at:  http://oto.sagepub.com/content/early/2011/06/02/0194599811409837.full.pdf.  Accessed on September 6, 2011.
8. Schecthter M.  American Academy of Pediatrics (AAP).  Technical Report:  Diagnosis and management of childhood obstructive sleep apnea syndrome.  Pediatrics. 2002; 109(4):1-41.  Available at:  http://pediatrics.aappublications.org/cgi/reprint/109/4/e69.  Accessed on September 6, 2011.

ARES Unicorder, Apnea Risk Evaluation System
Polysomnography
Portable Monitoring
Sleep Studies
Sleep Testing
SNAP^™
WATCH-PAT^™