In October 2012 the AASM published the AASM Manual for the Scoring of Sleep and Associated Events: Rules, Terminology and Technical Specifications Version 2.0.  All AASM accredited sleep centers will be required to follow the new manual by October 1, 2013. 

New Hypopnea Scoring Rules: One of the significant changes in Version 2.0 of the AASM Scoring Manual is the change to how hypopneas are scored.    Per the manual, you are instructed to “score a respiratory event as a hypopnea if ALL of the following criteria are met:

    a)      The peak signal excursions drop by ≥30 percent of pre-event baseline using nasal pressure (diagnostic study), PAP device flow (titration study) or an alternative hypopnea sensor (diagnostic study).
    b)      The duration of the ≥30 percent drop in signal excursion is ≥ 10 seconds.
    c)      There is a ≥3 percent oxygen desaturation from pre-event baseline or the event is associated with an arousal.”

Impact on Payment and Patient care: If faced with an audit, sleep centers and DME suppliers must be able to document compliance with payer requirements.  Payers can deny payment and even deny patients their equipment if documentation doesn’t comply.

Although the AASM requires a ≥3 percent desaturation when scoring hypopneas, a number of payers, including Medicare, still require ≥4 percent desaturation for reimbursement.  In such cases, Version 2.0 of the AASM Scoring Manual recommends reporting of hypopneas according to both definitions in order to comply with both accreditation and payer requirements.  Complying with payer requirements is critical for initial coverage of diagnostic testing and continued coverage of PAP therapy and supplies.