The effects of poor sleep are dauntingly pleiotropic. Inasmuch as sleep deprivation can behaviorally and physiologically mimic delirium in the ICU, there is concern that sleep deprived ICU patients are at risk for the increased mortality, longer hospital stays and worsened physical and mental outcomes of hospitalized patients who experience delirium during their admission. Furthermore, lack of sleep has been associated with decrements in FEV1, FVC and maximal inspiratory pressure in non-ICU COPD patients, increases in respiratory muscle fatigue in healthy volunteers and blunted response to hypercapnea in healthy volunteers. Finally, theoretical concerns exist regarding sleep loss putting patients at risk for prolonged bedrest, adverse cardiovascular events, derangement of metabolism and endocrine function as well as immune suppression; though supported by animal models and brief studies in healthy volunteers, no ICU data exists.