Sleep in the Intensive Care Unit measured by polysomnography.

Background: Sleep deprivation has deleterious effects on most organ systems. Patients in the Intensive care unit (ICU) report sleep deprivation as the second worst experience during their stay only superseded by pain. The aim of the review is to provide the clinician with knowledge of the optimal sleep-friendly care and environment.

Methods: Pubmed was systematically searched. Studies regarding polysomnography in ICU populations or healthy volunteers exposed to ICU conditions were included.

Results: Thirty-eight studies were identified. The patients were qualitatively but not necessarily quantitatively sleep deprived with loss of circadian rhythm and extreme sleep fragmentation. Sedation, care interventions, noise, disease and mechanical ventilation are the most contributing factors to sleep deprivation.

Conclusion: Sedation should be kept at a minimum and interrupted once daily. Care interventions should be clustered and noise reduced and/or masked with earplugs. NAVA, proportional assist+ or assist-control ventilation should be preferred to pressure support ventilation and adjusted to allow smaller tidal volumes, thus avoiding central apnoeas.