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Clinical value of polysomnography.
N J Douglas1, S Thomas, M A Jan
1Department of Medicine (RIE), City Hospital, Edinburgh, UK.
Lancet (London, England)
|February 8, 1992
Summary
Polysomnography
Area of Science:
- Sleep Medicine
- Respiratory Physiology
Background:
- Polysomnography is increasingly used for diagnosing sleep apnoea/hypopnoea syndrome (SAHS).
- Critical assessment of its diagnostic value is needed.
Purpose of the Study:
- To prospectively evaluate the diagnostic utility of electrophysiological and respiratory monitoring during polysomnography for SAHS.
Main Methods:
- Prospective study of 200 adult patients undergoing polysomnography.
- Analysis of electrophysiological recordings and respiratory events (apnoeas + hypopnoeas, A + H).
Main Results:
- Electrophysiological sleep recording provided no diagnostic value for SAHS.
- SAHS could be accurately defined by A + H per time in bed, not just time asleep.
- Oximetry alone diagnosed 66% of SAHS patients, but some with moderate SAHS were missed.
Conclusions:
- Neurophysiological sleep recording is unnecessary for SAHS diagnosis.
- Oximetry alone has limited value; comprehensive polysomnography is essential for accurate SAHS assessment and treatment planning.
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