Title:Disruption of Circadian Rhythms and Delirium, Sleep Impairment and Sepsis in Critically ill Patients. Potential Therapeutic Implications for Increased Light-Dark Contrast and Melatonin Therapy in an ICU Environment
Volume: 21
Issue: 24
Author(s): Carlos J. Madrid-Navarro, Rosa Sanchez-Galvez, Antonio Martinez-Nicolas, Ros Marina, Jose A. Garcia, Juan A. Madrid and Maria A. Rol
Affiliation:
Keywords:
Chronodisruption, chronoenhancement, circadian light, circadian rhythms, intensive care unit, melatonin.
Abstract: The confinement of critically ill patients in intensive care units (ICU) imposes environmental constancy
throughout both day and night (continuous light, noise, caring activities medications, etc.), which has a negative
impact on human health by inducing a new syndrome known as circadian misalignment, circadian disruption or
chronodisruption (CD). This syndrome contributes to poor sleep quality and delirium, and may impair septic states
frequently observed in critically ill patients. However, and although the bidirectional crosstalk between CD with
sleep impairment, delirium and inflammation in animal models has been known for years and has been suspected
in ICU patients, few changes have been introduced in the environment and management of ICU patients to improve
their circadian rhythmicity. Delirium, the most serious condition because it has a severe effect on prognosis and increases
mortality, as well as sleep impairment and sepsis, all three of them linked to disorganization of the circadian system in critically
ill patients, will be revised considering the functional organization of the circadian system, the main input and output signals that synchronize
the clock, including a brief description of the molecular circadian clock machinery, the non-visual effects of light, and the ICU
light environment. Finally, the potential usefulness of increased light/dark contrast and melatonin treatment in this context will be analyzed,
including some practical countermeasures to minimize circadian disruption and improve circadian system chronoenhancement,
helping to make these units optimal healing environments for patients.
