The first change appears in the coverage criteria section where CMS clarifies the definition of Central Sleep Apnea (CSA). Central Sleep Apnea is defined by the following criteria:
- The sum total of central apneas plus central hypopneas is greater than 50% of the total apneas and hypopneas; and
- A central apnea-central hypopnea index (CAHI) is greater than or equal to 5 events per hour; and
- The presence of at least one of the following:
- Difficulty initiating or maintaining sleep, frequent awakenings, or non-restorative sleep
- Awakening short of breath
- Witnessed apneas
- There is no evidence of daytime or nocturnal hypoventilation
- With use of a positive airway pressure device without a backup rate (E0601 or E0470), the polysomnogram (PSG) shows a pattern of apneas and hypopneas that demonstrates the persistence or emergence of central apneas or central hypopneas upon exposure to CPAP (E0601) or a bi-level device without backup rate (E0470) device when titrated to the point where obstructive events have been effectively treated (obstructive AHI less than 5 per hour).
- After resolution of the obstructive events, the sum total of central apneas plus central hypopneas is greater than 50% of the total apneas and hypopneas; and
- After resolution of the obstructive events, a central apnea-central hypopnea index (CAHI) greater than or equal to 5 per hour.
Additional language was included to qualify a patient with Severe COPD. In the prior policy, it states that before initiating therapy, Obstructive Sleep Apnea and treatment with a CPAP must be considered and ruled out. This statement is modified in the new policy to add a note indicating “Formal sleep testing is not required if there is sufficient information in the medical record to demonstrate that the beneficiary does not suffer from some form of sleep apnea (Obstructive Sleep Apnea (OSA), CSA and/or Comp SA) as the predominant cause of awake hypercapnia or nocturnal arterial oxygen desaturation.”
Criteria for qualifying a patient with Hypoventilation Syndrome for an E0470 and E0471 have also been modified significantly to address the use of a Home Sleep Study to determine oxygen saturation. The revision applies to the Hypoventilation diagnosis group, and the Coverage Guidance stipulates that not all types of HST are appropriate for CSA or Complex Sleep Apnea diagnosis groups). Under the prior policy, only a facility based PSG was allowed as a qualifying test for hypoventilation. The update adds a significant section on defining different types of sleep studies and defining which studies can be used to qualify a patient in specific diagnostic scenarios. This section also breaks down who may interpret the study (the same four parameters that exist in the PAP LCD: ABMS, ABSM, staff privileges at an accredited lab or residents waiting for their first exam in sleep medicine).
Throughout the policy, greater than and less than symbols are replaced with the written form.
It is important to consider these changes and how they will impact current protocols. In some cases these clarifications require additional scrutiny of the testing data and in others it opens the door to less restrictive requirements. Currently, the E0470 (Respiratory Assist Device) is under prepayment review in Jurisdiction D; however, when the data supports examination, other contractors often follow suite and initiate reviews for these codes.