Sleep during and following critical illness: A narrative review

Abstract

Sleep is a complex process influenced by biological and environmental factors. Disturbances of sleep quantity and quality occur frequently in the critically ill and remain prevalent in survivors for at least 12 mo. Sleep disturbances are associated with adverse outcomes across multiple organ systems but are most strongly linked to delirium and cognitive impairment. This review will outline the predisposing and precipitating factors for sleep disturbance, categorised into patient, environmental and treatment-related factors. The objective and subjective methodologies used to quantify sleep during critical illness will be reviewed. While polysomnography remains the gold-standard, its use in the critical care setting still presents many barriers. Other methodologies are needed to better understand the pathophysiology, epidemiology and treatment of sleep disturbance in this population. Subjective outcome measures, including the Richards-Campbell Sleep Questionnaire, are still required for trials involving a greater number of patients and provide valuable insight into patients’ experiences of disturbed sleep. Finally, sleep optimisation strategies are reviewed, including intervention bundles, ambient noise and light reduction, quiet time, and the use of ear plugs and eye masks. While drugs to improve sleep are frequently prescribed to patients in the ICU, evidence supporting their effectiveness is lacking.

Unmasking the hidden aftermath: postintensive care unit sequelae, discharge preparedness, and long-term follow-up

“…(10) However, currently, there is limited evidence available to guide the prevention of postsepsis morbidity or the management of patients who survive hospitalization for sepsis ( Table 3 ). ( 88 - 90 )…”

“…( 10 ) No entanto, atualmente, há poucas evidências disponíveis para orientar a prevenção de morbidade pós-sepse ou o manejo de pacientes que sobreviveram à internação por sepse ( Tabela 3 ). ( 88 - 90 )…”

Propofol improves sleep deprivation‐induced sleep structural and cognitive deficits via upregulating the BMAL1 expression and suppressing microglial M1 polarization

“… 3 Especially in the intensive care unit (ICU), 59–80% of ICU patients experience sleep disruptions such as sleep latency, fragmentation and circadian rhythm disturbances, 4 , 5 which are even in ICU patient survivors for at least 12 months. 6 The physical and psychological effects of sleep deprivation (SD) include cognitive impairment, 7 anxiety, 8 depression, 9 systemic inflammation, 10 and oxidative stress. 8 Besides, SD is closely associated with other common ICU complications, such as delirium.…”

“…According to the World Health Organization (WHO), the global rate of sleep disorders reaches 27%, and it is estimated that short‐term insomnia affects 30–50% of the population 3 . Especially in the intensive care unit (ICU), 59–80% of ICU patients experience sleep disruptions such as sleep latency, fragmentation and circadian rhythm disturbances, 4,5 which are even in ICU patient survivors for at least 12 months 6 . The physical and psychological effects of sleep deprivation (SD) include cognitive impairment, 7 anxiety, 8 depression, 9 systemic inflammation, 10 and oxidative stress 8 .…”