title: Clinical review: Sleep measurement in critical care patients: research and clinical implications.
abstract: Sleep disturbances are common in critically ill patients and have been characterised by numerous studies using polysomnography. Issues regarding patient populations, monitoring duration and timing (nocturnal versus continuous), as well as practical problems encountered in critical care studies using polysomnography are considered with regard to future interventional studies on sleep. Polysomnography is the gold standard in objectively measuring the quality and quantity of sleep. However, it is difficult to undertake, particularly in patients recovering from critical illness in an acute-care area. Therefore, other objective (actigraphy and bispectral index) and subjective (nurse or patient assessment) methods have been used in other critical care studies. Each of these techniques has its own particular advantages and disadvantages. We use data from an interventional study to compare agreement between four of these alternative techniques in the measurement of nocturnal sleep quantity. Recommendations for further developments in sleep monitoring techniques for research and clinical application are made. Also, methodological problems in studies validating various sleep measurement techniques are explored.
  
  
  BACKGROUND
  Current Controlled Trials ISRCTN47578325.
authors.affiliation: Sheffield Teaching Hospitals, Critical Care Directorate, Royal Hallamshire Hospital, Glossop Road, Sheffield, UK, S10 2JF. richard.bourne@sth.nhs.uk
authors.forename: Richard S
authors.initials: RS
authors.lastname: Bourne
authors.forename: Cosetta
authors.initials: C
authors.lastname: Minelli
authors.forename: Gary H
authors.initials: GH
authors.lastname: Mills
authors.forename: Rosalind
authors.initials: R
authors.lastname: Kandler
mesh_terms: D003422:Critical Care / Q000379:methods*; D004569:Electroencephalography / Q000379:methods; D006801:Humans; D009730:Nursing Assessment / Q000379:methods; D017286:Polysomnography / Q000379:methods; D012893:Sleep Wake Disorders / Q000175:diagnosis* / Q000451:nursing