Institute for Continuing Education

The Evolution of Portable OSA Monitoring

Course Objectives

Upon successful completion of this module, you will be able to:

• Analyze the current definitions and diagnostic criteria for obstructive sleep apnea (OSA) according to the International Classification of Sleep Disorders (ICSD-3) and AASM guidelines, including severity classifications based on the apnea-hypopnea index (AHI) and recognition of clinical subtypes.
• Evaluate the classification system for sleep study types (Type I through Type IV) established by the American Academy of Sleep Medicine, comparing the technical specifications, monitoring capabilities, and appropriate clinical applications of each device category.
• Synthesize the evidence base supporting home sleep apnea testing (HSAT), including validation studies, diagnostic accuracy compared to polysomnography, cost-effectiveness analyses, and patient satisfaction data that inform current clinical practice guidelines.
• Apply the AASM clinical practice guidelines and appropriate use criteria for HSAT, including patient selection considerations, conditions where in-laboratory polysomnography remains indicated, and recognition of clinical scenarios requiring comprehensive attended studies.
• Assess the technical requirements for HSAT devices, including sensor specifications, data acquisition standards, scoring methodology, quality assurance protocols, and interpretation of limited-channel recordings in the context of clinical presentations.
• Compare and contrast the advantages and limitations of HSAT versus in-laboratory polysomnography, evaluating factors including diagnostic sensitivity and specificity, patient accessibility, cost considerations, workflow implications, and impact on treatment outcomes.
• Explain the role of sleep technologists in HSAT programs, including patient education and device instruction, data download and quality review, technical troubleshooting, collaboration with interpreting physicians, and integration of HSAT into comprehensive sleep disorder management pathways.

Course Information

In this module, the authors retrospectively evaluated patients who had been referred to their sleep laboratory after undergoing a home sleep study with a portable device (SNAP; SNAP Laboratories; Glenview, IL). The home sleep study had been ordered by each patient’s primary care physician. The results show that the SNAP results frequently differed considerably from the polysomnography results. In approximately 65% of the patients studied, the severity of sleep apnea had been misclassified by the SNAP device relative to polysomnography! These differences included both “overdiagnoses” and “underdiagnoses,” and have the potential for serious ramifications.

Obstructive sleep apnea (OSA) is a highly prevalent disease with estimates that 20% of white men and women with body mass index between 25 and 28 kg/m2 have an apnea-hypopnea index (AHI) of 5.1 In recent years, OSA has been associated with a number of common morbid conditions, including heart disease, stroke, diabetes, and motor vehicle accidents. These links and the fact that the disease is readily treatable with nasal continuous positive airway pressure (CPAP) have accelerated the need for prompt and accurate diagnosis.