How to Practice Parameter Indications for Polysomnography

A polysomnography or sleep study monitors a patient overnight to confirm or disprove a diagnosis of sleep apnea. In a Stanford University study done in 2005, there were several diagnostic indications for conducting a sleep study, including apneic episodes, narcolepsy, periodic limb movement, neuromuscular disorders with accompanying seizures and depressive episodes with insomnia. Conversely, there are instances when polysomnography is contraindicated; these parameters include to diagnose chronic respiratory diseases, restless leg syndrome, parasomnias (sleep walking) and nonspecific seizures

Instructions

• 1

  Evaluate the patient's symptoms in the context of a sleep-related disorder. Patients who exhibit the classic symptoms of sleep apnea, including daytime sleepiness, narcolepsy, hypertension, limb movements while sleeping, anecdotal evidence of apneic episodes and obesity, generally meet the guidelines and parameters of a polysomnography.

• 2

  Rule out a diagnosis not related to sleep apnea. For example, a chronic lung condition, such as emphysema or asthma, will not meet the criteria for a sleep study due to the nature of the disease. No matter the organic cause of the apneic event, the patient must have enough qualifying events during the overnight polysomnography for the sleep apnea diagnosis. Medicare guidelines, generally considered the gold standard for insurance reimbursement, define a qualifying diagnosis of sleep apnea with an Apnea Hypopnea Index (AHI) of 15 or more events per hour or between five to 14 events with daytime somnolence (sleepiness). A simple oximetry or an overnight study will establish a respiratory condition not related to sleep apnea, such as Chronic Obstructive Pulmonary Disease (COPD) or Congestive Heart Failure (CHF).

• 3

  Establish that the patient meets the criteria for a diagnosis of sleep apnea. With regard to periodic limb movements, differentiate between restless leg syndrome and limb movements accompanying sleep apnea. According to the National Institutes of Health, restless leg syndrome occurs primarily in middle-aged adults and has no known cause. It may or may not produce insomnia in patients who experience no relief from the sensation unless they move their legs periodically. On the other hand, limb movements related to hypersomnia with sleep apnea have a source and accompany a 780.53 diagnosis.

• 4

  Identify neuromuscular disorders. Some disorders, such as Amyotrophic Lateral Sclerosis (ALS), can be treated via Bi-level Positive Airway Pressure (BiPAP) and require a qualifying polysomnography for insurance coverage. Due to the degenerative effects of ALS, BiPAP has been found efficacious in terms of promoting Activities of Daily Living by increasing the patient's quality of sleep.

• 5

  Rule out seizure disorders and sleep walking events that are unrelated to a diagnosis of sleep apnea. These do not meet the parameters indicated for a polysomnography because they generally do not obtain the qualifying AHI for a sleep apnea diagnosis. A sleep study may show seizure activity but should be undertaken by a neurologist and not a sleep medicine clinician.