Sleep Loss and Circadian Rhythm Disruption in the Intensive Care Unit

Pharmacologic Sleep Aids in the Intensive Care Unit: A Systematic Review

Background: Patients in the intensive care unit (ICU) often experience poor sleep quality. Pharmacologic sleep aids are frequently used as primary or adjunctive therapy to improve sleep, although their benefits in the ICU remain uncertain. This review aims to provide a comprehensive assessment of the objective and subjective effects of medications used for sleep in the ICU, as well as their adverse effects. Methods: PubMed, Web of Science, Scopus, Embase, and Cochrane Central Register of Controlled Trials were systematically searched from their inception until June 2023 for comparative studies assessing the effects of pharmacologic sleep aids on objective and subjective metrics of sleep. Results: Thirty-four studies with 3498 participants were included. Medications evaluated were melatonin, ramelteon, suvorexant, propofol, and dexmedetomidine. The majority of studies were randomized controlled trials. Melatonin and dexmedetomidine were the best studied agents. Objective sleep metrics included polysomnography (PSG), electroencephalography (EEG), bispectral index, and actigraphy. Subjective outcome measures included patient questionnaires and nursing observations. Evidence for melatonin as a sleep aid in the ICU was mixed but largely not supportive for improving sleep. Evidence for ramelteon, suvorexant, and propofol was too limited to offer definitive recommendations. Both objective and subjective data supported dexmedetomidine as an effective sleep aid in the ICU, with PSG/EEG in 303 ICU patients demonstrating increased sleep duration and efficiency, decreased arousal index, decreased percentage of stage N1 sleep, and increased absolute and percentage of stage N2 sleep. Mild bradycardia and hypotension were reported as side effects of dexmedetomidine, whereas the other medications were reported to be safe. Several ongoing studies have not yet been published, mostly on melatonin and dexmedetomidine. Conclusions: While definitive conclusions cannot be made for most medications, dexmedetomidine improved sleep quantity and quality in the ICU. These benefits need to be balanced with possible hemodynamic side effects.

Circadian rhythms in solid organ transplantation

Circadian rhythms are daily cycles in physiology that can affect medical interventions. This review considers how these rhythms may relate to solid organ transplantation. It begins by summarizing the mechanism for circadian rhythm generation known as the molecular clock, and basic research connecting the clock to biological activities germane to organ acceptance. Next follows a review of clinical evidence relating time of day to adverse transplantation outcomes. The concluding section discusses knowledge gaps and practical areas where applying circadian biology might improve transplantation success.

Sleep, anxiety, depression, and stress in critically ill patients: a descriptive study in a Portuguese intensive care unit

BACKGROUND

Sleep disorders are common among patients admitted to intensive care units (ICUs). This study aimed to assess the perceptions of sleep quality, anxiety, depression, and stress reported by ICU patients and the relationships between these perceptions and patient variables.

METHODS

This cross-sectional study used consecutive non-probabilistic sampling to select participants. All patients admitted for more than 72 hours of ICU hospitalization at a Portuguese hospital between March and June 2020 were asked to complete the "Richard Campbell Sleep Questionnaire" and "Anxiety, depression, and Stress Assessment Questionnaire." The resulting data were analyzed using descriptive statistics, Pearson's correlation coefficient, Student t-tests for independent samples, and analysis of variance. The significance level for rejecting the null hypothesis was set to α ≤0.05.

RESULTS

A total of 52 patients admitted to the ICU for at least 72 hours was recruited. The mean age of the participants was 64 years (standard deviation, 14.6); 32 (61.5%) of the participants were male. Approximately 19% had psychiatric disorders. The prevalence of self-reported poor sleep was higher in women (t[50]=2,147, P=0.037) and in participants with psychiatric problems, although this difference was not statistically significant (t[50]=-0.777, P=0.441). Those who reported having sleep disorders before hospitalization had a worse perception of their sleep.

CONCLUSIONS

Sleep quality perception was worse in female ICU patients, those with psychiatric disorders, and those with sleep alterations before hospitalization. Implementing early interventions and designing nonpharmacological techniques to improve sleep quality of ICU patients is essential.

Using routinely collected clinical data for circadian medicine: A review of opportunities and challenges

A wealth of data is available from electronic health records (EHR) that are collected as part of routine clinical care in hospitals worldwide. These rich, longitudinal data offer an attractive object of study for the field of circadian medicine, which aims to translate knowledge of circadian rhythms to improve patient health. This narrative review aims to discuss opportunities for EHR in studies of circadian medicine, highlight the methodological challenges, and provide recommendations for using these data to advance the field. In the existing literature, we find that data collected in real-world clinical settings have the potential to shed light on key questions in circadian medicine, including how 24-hour rhythms in clinical features are associated with-or even predictive of-health outcomes, whether the effect of medication or other clinical activities depend on time of day, and how circadian rhythms in physiology may influence clinical reference ranges or sampling protocols. However, optimal use of EHR to advance circadian medicine requires careful consideration of the limitations and sources of bias that are inherent to these data sources. In particular, time of day influences almost every interaction between a patient and the healthcare system, creating operational 24-hour patterns in the data that have little or nothing to do with biology. Addressing these challenges could help to expand the evidence base for the use of EHR in the field of circadian medicine.

Enteral feeding strategies in patients with acute gastrointestinal injury: From limited to progressive to open feeding

Acute gastrointestinal injury (AGI) is very common in critically ill patients, and its severity is positively correlated with mortality. Critically ill patients with digestive and absorption dysfunction caused by AGI face higher nutritional risks, making nutritional support particularly important. Early enteral nutrition (EN) support is extremely important because it can promote the recovery of intestinal function, protect the intestinal mucosal barrier, reduce microbiota translocation, reduce postoperative complications, shorten hospital stay, and improve clinical prognosis. In recent years, many nutritional guidelines have been proposed for critically ill patients; however, there are few recommendations for the implementation of EN in patients with AGI, and their quality of evidence is low. The use of EN feeding strategies in critically ill patients with AGI remains controversial. The aim of this review was to elaborate on how EN feeding strategies should transition from limited to progressive to open feeding and explain the time window for this transition.

Changes in Body Temperature Patterns Are Predictive of Mortality in Septic Shock: An Observational Study

Biological rhythms are important regulators of immune functions. In intensive care unit (ICU), sepsis is known to be associated with rhythm disruption. Our objectives were to determine factors associated with rhythm disruption of the body temperature and to assess the relationship between temperature and mortality in septic shock patients; In a cohort of septic shock, we recorded body temperature over a 24-h period on day 2 after ICU admission. For each patient, the temperature rhythmicity was assessed by defining period and amplitude, and the adjusted average (mesor) of the temperature by sinusoidal regression and cosinor analysis. Analyses were performed to assess factors associated with the three temperature parameters (period, amplitude, and mesor) and mortality. 162 septic shocks were enrolled. The multivariate analysis demonstrates that the period of temperature was associated with gender (women, coefficient -2.2 h, p = 0.031) and acetaminophen use (coefficient -4.3 h, p = 0.002). The mesor was associated with SOFA score (coefficient -0.05 °C per SOFA point, p = 0.046), procalcitonin (coefficient 0.001 °C per ng/mL, p = 0.005), and hydrocortisone use (coefficient -0.5 °C, p = 0.002). The amplitude was associated with the dialysis (coefficient -0.5 °C, p = 0.002). Mortality at day 28 was associated with lower mesor (adjusted hazard ratio 0.50, 95% CI 0.28 to 0.90; p = 0.02), and higher amplitude (adjusted hazard ratio 5.48, 95% CI 1.66 to 18.12; p = 0.005) of temperature. Many factors, such as therapeutics, influence the body temperature during septic shock. Lower mesor and higher amplitude were associated with mortality and could be considered prognostic markers in ICU. In the age of artificial intelligence, the incorporation of such data in an automated scoring alert could compete with physicians to identify high-risk patients during septic shock.

Society of Anesthesia and Sleep Medicine Position Paper on Patient Sleep During Hospitalization

This article addresses the issue of patient sleep during hospitalization, which the Society of Anesthesia and Sleep Medicine believes merits wider consideration by health authorities than it has received to date. Adequate sleep is fundamental to health and well-being, and insufficiencies in its duration, quality, or timing have adverse effects that are acutely evident. These include cardiovascular dysfunction, impaired ventilatory function, cognitive impairment, increased pain perception, psychomotor disturbance (including increased fall risk), psychological disturbance (including anxiety and depression), metabolic dysfunction (including increased insulin resistance and catabolic propensity), and immune dysfunction and proinflammatory effects (increasing infection risk and pain generation). All these changes negatively impact health status and are counterproductive to recovery from illness and operation. Hospitalization challenges sleep in a variety of ways. These challenges include environmental factors such as noise, bright light, and overnight awakenings for observations, interventions, and transfers; physiological factors such as pain, dyspnea, bowel or urinary dysfunction, or discomfort from therapeutic devices; psychological factors such as stress and anxiety; care-related factors including medications or medication withdrawal; and preexisting sleep disorders that may not be recognized or adequately managed. Many of these challenges appear readily addressable. The key to doing so is to give sleep greater priority, with attention directed at ensuring that patients' sleep needs are recognized and met, both within the hospital and beyond. Requirements include staff education, creation of protocols to enhance the prospect of sleep needs being addressed, and improvement in hospital design to mitigate environmental disturbances. Hospitals and health care providers have a duty to provide, to the greatest extent possible, appropriate preconditions for healing. Accumulating evidence suggests that these preconditions include adequate patient sleep duration and quality. The Society of Anesthesia and Sleep Medicine calls for systematic changes in the approach of hospital leadership and staff to this issue. Measures required include incorporation of optimization of patient sleep into the objectives of perioperative and general patient care guidelines. These steps should be complemented by further research into the impact of hospitalization on sleep, the effects of poor sleep on health outcomes after hospitalization, and assessment of interventions to improve it.

Actigraphy-based sleep and activity measurements in intensive care unit patients randomized to ramelteon or placebo for delirium prevention

Patients in the ICU often sleep poorly for various reasons, which may predispose to delirium. We previously conducted a clinical trial in which we tested the efficacy of ramelteon, a melatonin-receptor agonist used to treat insomnia, versus placebo, in preventing ICU delirium in patients who underwent elective pulmonary thromboendarterectomy (PTE) surgery. Here we examine sleep, activity, and circadian patterns, measured with actigraphy, to understand changes in these metrics with our intervention and in those with and without delirium. Participants wore wrist actigraphy devices while recovering post-operatively in the ICU. For sleep analysis, we extracted total sleep time and sleep fragmentation metrics over the 22:00 to 06:00 period nightly, and daytime nap duration from the daytime period (0:600 to 22:00) for each participant. For activity analyses, we extracted the following metrics: total daytime activity count (AC), maximum daytime AC, total nighttime AC, and maximum nighttime AC. Next, we performed a nonparametric circadian analysis on ACs over each 24-h day and extracted the following: interdaily stability (IS), intra-daily variability (IV), relative amplitude (RA), and low and high periods of activity (L5 and M10) as well as their start times. These metrics were compared between patients who received ramelteon versus placebo, and between patients who became delirious versus those who did not develop delirium. We additionally made comparisons between groups for daytime and nighttime light levels. No differences in sleep, activity, circadian metrics or light levels were found between drug groups. Delirious patients, when compared to those who were never delirious, had a lower IS (0.35 ± 0.16 vs. 0.47 ± 0.23; P = 0.006). Otherewise, no differences in IV, L5, M10, or RA were found between groups. L5 and M10 activity values increased significantly over the post-extubation for the whole cohort. No differences were found for daytime or nighttime light levels between groups. Overall, ramelteon did not impact sleep or circadian metrics in this cohort. Consistent with clinical experience, delirious patients had less inter-daily stability in their rest-activity rhythms. These data suggest that actigraphy might have value for individual assessment of sleep in the ICU, and for determining and detecting the impact of interventions directed at improving sleep and circadian activity rhythms in the ICU.Trial registration: REGISTERED at CLINICALTRIALS.GOV: NCT02691013. Registered on February 24, 2016 by principal investigator, Dr. Robert L. Owens.

Psychometric properties of the Turkish version of modified Freedman questionnaire for sleep quality

To investigate the psychometric characteristics of the modified Freedman Sleep Quality Questionnaire (mFSQQ) to assess sleep in Turkish intensive care unit (ICU) patients. This prospective cross-sectional study was conducted between December 2020 and August 2021 with patients older than 18 years, who stayed in the ICU for ≥ 24 h and were cooperative with a Glasgow Coma Scale score ≥ 10 in medical and surgical ICUs of a university hospital. During the adaptation of the items of the mFSQQ, language, content, and construct validity were examined, and the test-retest method and internal consistency were used to examine its reliability. The content validity index of the questionnaire was 0.82. The Kaiser-Meyer-Olkin measure of sampling adequacy was 0.71, which indicates adequate sampling; Bartlett's test of sphericity was χ2 = 2868.97, p < 0.001. The Turkish version had three subscales. The factor loadings of the items were above 0.30, and the factors explained 60.59% of the total variance. The test-retest reliability coefficient was 0.85, indicating high consistency. The Cronbach α reliability coefficient was 0.80, indicating high reliability. The item-total correlations were found to be sufficient (between 0.25 and 0.78). The Turkish version of the mFSQQ showed good psychometric characteristics and can be used as a routine evaluation instrument to determine sleep quality by the ICU team and to promote sleep.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-022-00389-2.

Patients' Self-Reported Recovery After an Environmental Intervention Aimed to Support Patient's Circadian Rhythm in Intensive Care

BACKGROUND

Patients in intensive care units (ICUs) are among the most vulnerable, and they require support to start their recovery. The design of the patient area in the ICU can play a prominent role in both the quality of care and patients' recovery. The lighting environment has the opportunity to restore and strengthen the natural human circadian rhythm and health.

AIM

To evaluate patients' self-reported recovery after being cared for in an ICU room rebuilt according to evidence-based design principles that promote recovery.

METHOD

An intervention was set up in a two-bed patient room including a cycled lighting system. Self-reported recovery was reported at 6 and 12 months after discharge. Data were analyzed using a 2(mechanically ventilated, nonmechanically ventilated) × 2(intervention room, ordinary room) analysis of covariance (ANCOVA) and 2(male, women) × 2(intervention room, ordinary room) ANCOVA.

RESULTS

Data from the different rooms showed no significant main effects for recovery after 6 months, p = .21; however, after 12 months, it become significant, p. < .05. This indicated that patient recovery was positively influenced for patients cared for in the intervention room (M = 8.88, SD = 4.07) compared to the ordinary room (M = 10.90, SD = 4.26). There were no interaction effects for gender or if the patients had been mechanically ventilated either at 6 or 12 months' postdischarge.

CONCLUSIONS

A cycled lighting system may improve patient self-reported recovery after ICU care; however, more research on the topic is needed.

Non-pharmacological sleep interventions for adult patients in intensive care Units: A systematic review

OBJECTIVES

To synthesize and evaluate current non-pharmacological sleep interventions for critically ill adult patients in intensive care units and provide recommendations for future studies of non-pharmacological means of improving this population's sleep quality.

RESEARCH METHODOLOGY/DESIGN

The literature search was conducted following PRISMA guidelines. Seven databases CINAHL, PsycINFO, Embase, Medline, Cochrane Library, Web of Science, and Scopus and three keywords, sleep, intervention and intensive care unit were employed. All possible combinations of the keywords and similar words were considered. Included studies were primary studies, involved adult intensive care unit patients, focused on non-pharmacological sleep interventions, measured subjective and/or objective sleep quality and were published in English between January 2010 and September 2020.

RESULTS

The 20 included studies examined different types of non-pharmacological sleep interventions involving use of earplugs, an eye mask, white noise, music, aromatherapy, massage, acupressure, light intensity, a sleep hygiene protocol, quiet time and minimization of nursing care. Of 18 studies employing an experimental design, most reported that non-pharmacological interventions improved sleep quality. All these interventions involved environmental factors or complementary relaxation strategies.

CONCLUSIONS

Non-pharmacological sleep interventions can have a positive influence on sleep quality in critically ill patients, but more research is needed to determine their effectiveness.

A Prospective Study Evaluating Sleep Quality and Disorders in Post-ARDS Patients

Introduction

Critically ill patients are predisposed to developing sleep disorders due to multiple factors like pre-existing sleep disorders, severe acute illness, sleep-altering medical interventions, and the disturbing intensive care unit (ICU) environment. In the current study, a multi-modality approach has been attempted to capture the different aspects of sleep disturbances, including insomnia (using ISI), daytime sleepiness (using ESS), sleep quality (using PSQI), sleep architecture, and SDB (using PSG).

Materials and Methods

The eligible ARDS survivor patients were updated about the study's design prior to hospital discharge. At admission, data regarding demographic details, clinical history, etiology of ARDS, and PaO₂/FiO₂ (P/F) ratio at presentation, Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores was collected. All enrolled patients were evaluated twice (early-within 7 days of admission and late-after 6 weeks of discharge) by the Richards-Campbell Sleep Questionnaire (RCSQ), Insomnia severity index (ISI), and level 1 PSG. Additionally, ESS questionnaire and the Pittsburgh Sleep Quality Index (PSQI) were also recorded in late evaluation. Abnormal sleep was defined if one or more of the following characteristics met: ISI > 15, ESS > 10, global PSQI > 5, AHI ≥ 5 events/h.

Results

Thirty patients were recruited out of the total of 88 ARDS patients screened at admission. The median (IQR) PaO₂/FiO₂ ratio and APACHE II scores were 176 (151-191.5) and 14 (14-16), respectively. The median (IQR) duration of stay in the ICU was 10 (7.3-19.5) days. The median RCSQ score in the early and late evaluation was 42 and 69, respectively. The mean ISI score in the early evaluation was 16.67 ± 4.72, which decreased to 11.70 ± 5.03 in late evaluation (p < 0.05). ISI score > 15 (clinical insomnia) was found in 18 out of 30 subjects (60%) in early evaluation and 11 out of 30 (36%) in late evaluation. During the early evaluation, sleep efficiency was low (median 59.9% and predominantly N1 and N2) which improved in late evaluation (median 80.6%). Of the 30 patients, only 4 had AHI > 5 in early evaluation and none in late evaluation. Neither of P/F ratio, SOFA, and APACHE II scores did correlate with ICU events in the early and late evaluations. Regression analysis showed subjects with ICU stay more than 10 days, duration of IMV more than 7 days, Fentanyl more than 7 mg, duration of sedative use more than 7 days was independently associated with poor objective sleep quality (low sleep efficiency, low TST and high arousal index) during the early and late evaluations after ICU discharge compared to counterparts (p value < 0.05).

Conclusion

We conclude that sleep quality in ARDS survivors was poor within 7 days of ICU discharge, characterized by severe disruption of sleep architecture and sleep-disordered breathing. After 6 weeks of ICU discharge sleep quality showed significant improvement in the N3 stage and AHI, however persistent insomnia was observed even at 6 weeks. Therefore, prior identification of risk factors and early diagnosis of sleep quality disorders in post-ARDS patients is essential.

Sleep and circadian rhythm disturbances in intensive care unit (ICU)-acquired delirium: a case-control study

OBJECTIVE

The relationships among sleep, circadian rhythm, and intensive care unit (ICU)-acquired delirium are complex and remain unclear. This study aimed to examine the pathophysiological mechanisms of sleep and circadian rhythm disturbances in patients with ICU-acquired delirium.

METHODS

This study included critical adult patients aged 18 to 75 years who were treated in the ICU. Twenty-four-hour polysomnography was performed and serum melatonin and cortisol levels were measured six times during polysomnography. Receiver operating characteristic curves and binomial logistic regression were used to evaluate the potential of sleep, melatonin, and cortisol as indicators of delirium in the ICU.

RESULTS

Patients with delirium (n = 24) showed less rapid eye movement (REM) sleep compared with patients without delirium (n = 24, controls). Melatonin levels were lower and cortisol levels were higher in the delirium group than in the control group. REM sleep, melatonin, and cortisol were significantly associated with delirium. The optimal cutoff values of REM sleep and mean melatonin and cortisol levels that predicted delirium were ≤1.05%, ≤422.09 pg/mL, and ≥212.14 ng/mL, respectively.

CONCLUSIONS

REM sleep, and melatonin and cortisol levels are significantly associated with the risk of ICU-acquired delirium. Improved sleep and readjustment of circadian rhythmicity may be therapeutic targets of ICU-acquired delirium.

A Timely Call to Arms: COVID-19, the Circadian Clock, and Critical Care

We currently find ourselves in the midst of a global coronavirus disease 2019 (COVID-19) pandemic, caused by the highly infectious novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Here, we discuss aspects of SARS-CoV-2 biology and pathology and how these might interact with the circadian clock of the host. We further focus on the severe manifestation of the illness, leading to hospitalization in an intensive care unit. The most common severe complications of COVID-19 relate to clock-regulated human physiology. We speculate on how the pandemic might be used to gain insights on the circadian clock but, more importantly, on how knowledge of the circadian clock might be used to mitigate the disease expression and the clinical course of COVID-19.

Nurses' autonomy in sleep management improves patients' sleep quality: A cross-sectional study

BACKGROUND

The current literature indicates that intensive care (ICU) patients' sleep quality is generally poor, which is associated with serious physical and psychological consequences.

AIMS AND OBJECTIVES

To describe the practices nurses use to provide good-quality sleep to adult ICU patients and assess nurses' perceptions of patients' sleep quality and nurses' professional autonomy in sleep management.

DESIGN

A descriptive-correlational, cross-sectional study.

METHODS

A total of 232 ICU nurses from four hospitals in Poland were recruited. Data were collected between May and August 2019 using a previously developed questionnaire and analysed using descriptive statistics and non-parametric tests.

RESULTS

A total of 119 nurses took part in the study (response rate: 51%). On average, nurses rated patients' sleep quality as moderate (4.44 ± 2.23, scale 0-10). Most of the respondents (95.8%) said they did not use any sleep protocol. Various strategies to improve patients' sleep were used sporadically (2.64 ± 1.55, scale 1-5). The use of sleep quality assessment methods was positively correlated with patients' sleep quality (rho = 0.22, P = .02). Nurses' professional autonomy regarding sleep management was assessed as average (4.34 ± 2.43, scale 0-10) and was correlated with the patients' sleep quality (rho = 0.25, P < .01). Nurses who rated their autonomy in patients' sleep management more highly (rho = 0.29, P < .01) and more often influenced patients' sleep decisions (rho = 0.24, P < .01) used more methods to improve patients' sleep.

CONCLUSIONS

Strengthening the professional autonomy of ICU nurses and creating a reliable sleep assessment and improvement tool, which would describe strategies nurses can implement independently could increase sleep quality among ICU patients.

RELEVANCE TO CLINICAL PRACTICE

Addressing organizational problems, which hamper the patients' sleep management by ICU nurses could result in using more strategies to provide good-quality sleep to ICU patients. There is a need for clinical guidelines regarding patients' sleep management to help educate and guide nurses how to independently use sleep improvement methods.

Metabolomics Pilot Study Identifies Desynchronization of 24-H Rhythms and Distinct Intra-patient Variability Patterns in Critical Illness: A Preliminary Report

Background: Synchronized circadian rhythms play a key role in coordinating physiologic health. Desynchronized circadian rhythms may predispose individuals to disease or be indicative of underlying disease. Intensive care unit (ICU) patients likely experience desynchronized circadian rhythms due to disruptive environmental conditions in the ICU and underlying pathophysiology. This observational pilot study was undertaken to determine if 24-h rhythms are altered in ICU patients relative to healthy controls by profiling 24-h rhythms in vital signs and plasma metabolites.

Methods: We monitored daily rhythms in 5 healthy controls and 5 ICU patients for 24 h. Heart rate and blood pressure were measured every 30 min, temperature was measured every hour, and blood was sampled for mass spectrometry-based plasma metabolomics every 4 h. Bedside sound levels were measured every minute. Twenty-four hours rhythms were evaluated in vitals and putatively identified plasma metabolites individually and in each group using the cosinor method.

Results: ICU patient rooms were significantly louder than healthy controls' rooms and average noise levels were above EPA recommendations. Healthy controls generally had significant 24-h rhythms individually and as a group. While a few ICU patients had significant 24-h rhythms in isolated variables, no significant rhythms were identified in ICU patients as a group, except in cortisol. This indicates a lack of coherence in phases and amplitudes among ICU patients. Finally, principal component analysis of metabolic profiles showed surprising patterns in plasma sample clustering. Each ICU patient's samples were clearly discernable in individual clusters, separate from a single cluster of healthy controls.

Conclusions: In this pilot study, ICU patients' 24-h rhythms show significant desynchronization compared to healthy controls. Clustering of plasma metabolic profiles suggests that metabolomics could be used to track individual patients' clinical courses longitudinally. Our results show global disordering of metabolism and the circadian system in ICU patients which should be characterized further in order to determine implications for patient care.

Practices for promoting sleep in intensive care units in Brazil: a national survey

Objective

To conduct a national survey of intensive care professionals to identify the practices for promoting sleep in adult intensive care units in Brazil and describe the professionals’ perceptions of the importance of sleep for patients.

Methods

An electronic questionnaire was distributed by the clinical research cooperation network of the Associação de Medicina Intensiva Brasileira and by the Brazilian Research in Intensive Care Network to physicians and nurses registered with the association. The questionnaire evaluated the profile of the respondents, the profile of their intensive care units, whether protocols for promoting sleep were present, the pharmacological and nonpharmacological measures typically employed in the unit, and the professionals’ perceptions regarding sleep in critically ill patients.

Results

A total of 118 questionnaires were evaluated. The Southeast region of the country was the most represented (50 questionnaires, 42.4%). The majority of units had a clinical-surgical profile (93 questionnaires; 78.8%), and 26 had a continuous visitation policy (22.0%). Only 18 intensive care units (15.3%) reported having protocols for promoting sleep. The most cited measure for sleep promotion was reducing light during the night (95 questionnaires; 80.5%), which was more often performed in private intensive care units. Almost all of the responders (99%) believed that poor-quality sleep has a negative impact on patient recovery.

Conclusion

The responses to this Brazilian survey revealed that few intensive care units had a program for promoting sleep, although almost all participants recognized the importance of sleep in patient recovery.

Ramelteon for Prevention of Postoperative Delirium: A Randomized Controlled Trial in Patients Undergoing Elective Pulmonary Thromboendarterectomy

OBJECTIVES

To assess the efficacy of ramelteon in preventing delirium, an acute neuropsychiatric condition associated with increased morbidity and mortality, in the perioperative, ICU setting.

DESIGN

Parallel-arm, randomized, double-blinded, placebo-controlled trial.

SETTING

Academic medical center in La Jolla, California.

PATIENTS

Patients greater than or equal to 18 years undergoing elective pulmonary thromboendarterectomy.

INTERVENTIONS

Ramelteon 8 mg or matching placebo starting the night prior to surgery and for a maximum of six nights while in the ICU.

MEASUREMENTS AND MAIN RESULTS

Incident delirium was measured twice daily using the Confusion Assessment Method-ICU. The safety outcome was coma-free days assessed by the Richmond Agitation-Sedation Scale. One-hundred twenty participants were enrolled and analysis completed in 117. Delirium occurred in 22 of 58 patients allocated to placebo versus 19 of 59 allocated to ramelteon (relative risk, 0.8; 95% CI, 0.5-1.4; p = 0.516). Delirium duration, as assessed by the number of delirium-free days was also similar in both groups (placebo median 2 d [interquartile range, 2-3 d] vs ramelteon 3 d [2-5 d]; p = 0.181). Coma-free days was also similar between groups (placebo median 2 d [interquartile range, 1-3 d] vs ramelteon 3 d [2-4 d]; p = 0.210). We found no difference in ICU length of stay (median 4 d [interquartile range, 3-5 d] vs 4 d [3-6 d]; p = 0.349), or in-hospital mortality (four vs three deaths; relative risk ratio, 0.7; 95% CI, 0.2-3.2; p = 0.717), all placebo versus ramelteon, respectively.

CONCLUSIONS

Ramelteon 8 mg did not prevent postoperative delirium in patients admitted for elective cardiac surgery.

Differential Thermoregulatory and Inflammatory Patterns in the Circadian Response to LPS-Induced Septic Shock

Sepsis is caused by a dysregulated host response to infection, and characterized by uncontrolled inflammation together with immunosuppression, impaired innate immune functions of phagocytes and complement activation. Septic patients develop fever or hypothermia, being the last one characteristic of severe cases. Both lipopolysaccharide (LPS) and Tumor Necrosis Factor (TNF)-α- induced septic shock in mice is dependent on the time of administration. In this study, we aimed to further characterize the circadian response to high doses of LPS. First, we found that mice injected with LPS at ZT11 developed a higher hypothermia than those inoculated at ZT19. This response was accompanied by higher neuronal activation of the preoptic, suprachiasmatic, and paraventricular nuclei of the hypothalamus. However, LPS-induced Tnf-α and Tnf-α type 1 receptor (TNFR1) expression in the preoptic area was time-independent. We also analyzed peritoneal and spleen macrophages, and observed an exacerbated response after ZT11 stimulation. The serum of mice inoculated with LPS at ZT11 induced deeper hypothermia in naïve animals than the one coming from ZT19-inoculated mice, related to higher TNF-α serum levels during the day. We also analyzed the response in TNFR1-deficient mice, and found that both the daily difference in the mortality rate, the hypothermic response and neuronal activation were lost. Moreover, mice subjected to circadian desynchronization showed no differences in the mortality rate throughout the day, and developed lower minimum temperatures than mice under light-dark conditions. Also, those injected at ZT11 showed increased levels of TNF-α in serum compared to standard light conditions. These results suggest a circadian dependency of the central thermoregulatory and peripheral inflammatory response to septic-shock, with TNF-α playing a central role in this circadian response.

Use of actigraphy to characterize inactivity and activity in patients in a medical ICU

BACKGROUND

In the intensive care unit (ICU), inactivity is common, contributing to ICU-acquired weakness and poor outcomes. Actigraphy may be useful for measuring activity in the ICU.

OBJECTIVES

To use actigraphy to characterize inactivity and activity in critically ill patients.

METHODS

This prospective observational study involved 48-h wrist actigraphy in medical ICU (MICU) patients, with activity data captured across 30-s epochs. Inactivity (zero-activity epochs) and activity (levels of non-zero activity) were summarized across key patient (e.g., age) and clinical (e.g., mechanical ventilation status) variables, and compared using multivariable regression.

RESULTS

Overall, 189,595 30-s epochs were collected in 34 MICU patients. Zero-activity (inactivity) comprised 122,865 (65%) of epochs; these epochs were 24% and 13% more prevalent, respectively, in patients receiving mechanical ventilation (versus none, p < 0.001) and in the highest (versus lowest) organ failure score tertile (p = 0.03). Ambulatory (versus non-ambulatory) patients exhibited more non-zero activity (35 more movements per epoch, p < 0.001), while those in the highest (versus lowest) organ failure score tertile exhibited less activity (22 fewer movements per epoch, p = 0.03). Significant inactivity/activity differences were not observed when evaluated based on age, sedation, or restraint status.

CONCLUSIONS

Actigraphy demonstrated that MICU patients are profoundly inactive, including those who are young, non-sedated and non-restrained. Hence, ICU-specific, non-patient-related factors may contribute to inactivity, an issue requiring further investigation.

Sleep and Circadian Rhythms in Survivors of Acute Respiratory Failure

Background: Little is known about sleep and circadian rhythms in survivors of acute respiratory failure (ARF) after hospital discharge. Objectives: To examine sleep and rest-activity circadian rhythms in ARF survivors 3 months after hospital discharge, and to compare them with a community-dwelling population. Methods: Sleep diary, actigraphy data, and insomnia symptoms were collected in a pilot study of 14 ARF survivors. Rest-activity circadian rhythms were assessed with wrist actigraphy and sleep diary for 9 days, and were analyzed by cosinor and non-parametric circadian rhythm analysis. Results: All participants had remarkable actigraphic sleep fragmentation, 71.5% had subclinical or clinical insomnia symptoms. Compared to community-dwelling adults, this cohort had less stable rest-activity circadian rhythms (p < 0.001), and weaker circadian strength (p < 0.001). Conclusion: Insomnia and circadian disruption were common in ARF survivors. Sleep improvement and circadian rhythm regularity may be a promising approach to improve quality of life and daytime function after ARF.

Perfect timing: circadian rhythms, sleep, and immunity - an NIH workshop summary

Recent discoveries demonstrate a critical role for circadian rhythms and sleep in immune system homeostasis. Both innate and adaptive immune responses - ranging from leukocyte mobilization, trafficking, and chemotaxis to cytokine release and T cell differentiation -are mediated in a time of day-dependent manner. The National Institutes of Health (NIH) recently sponsored an interdisciplinary workshop, "Sleep Insufficiency, Circadian Misalignment, and the Immune Response," to highlight new research linking sleep and circadian biology to immune function and to identify areas of high translational potential. This Review summarizes topics discussed and highlights immediate opportunities for delineating clinically relevant connections among biological rhythms, sleep, and immune regulation.

Brighter Days May Be Ahead: Continuous Measurement of Pediatric Intensive Care Unit Light and Sound

Objective: To describe light and sound characteristics in the rooms of critically ill children. Design: Prospective observational cohort study, with continuously measured light and sound levels. Setting: Tertiary care pediatric intensive care unit (PICU), with a newly constructed expansion and an older, pre-existing section. Patients: Critically ill patients 0-18 years old, requiring respiratory or cardiovascular support. Patients with severe cognitive pre-conditions were excluded. Measurements and Main Results: One hundred patients were enrolled, totaling 602 patient-days. The twenty-four hour median illuminance was 16 (IQR 5-53) lux (lx). Daytime (07:00-21:00) median light level was 27 lx (IQR 13-82), compared with 4 lx (IQR 1-10) overnight (22:00-06:00). Peak light levels occurred midday between 11:00 and 14:00, with a median of 48 lx (IQR 24-119). Daytime median illuminance trended higher over the course of admission, whereas light levels overnight were consistent. Midday light levels were higher in newly constructed rooms: 78 lx (IQR 30-143) vs. 26 lx (IQR 20-40) in existing rooms. The twenty-four hour median equivalent sound level (LAeq) was 60 (IQR 55-64) decibels (dB). Median daytime LAeq was 62 dB (IQR 58-65) and 56 dB (IQR 52-61) overnight. On average, 35% of patients experienced at least one sound peak >80 dB every hour from 22:00 to 06:00. Overnight peaks, but not median sound levels nor daytime peaks, decreased over the course of admission. There was no difference in sound between new and pre-existing rooms. Conclusions: This study describes continuously measured light and sound in PICU rooms. Light levels were low even during daytime hours, while sound levels were consistently higher than World Health Organization hospital room recommendations of <35 dB. Given the relevance of light and sound to sleep/wake patterns, and evidence of post-intensive care syndromes, the clinical effects of light and sound on critically ill children should be further explored as potentially modifiable environmental factors.

Sleep and Delirium in Adults Who Are Critically Ill: A Contemporary Review

Sleep is important to health and well-being, and studies in healthy adults have demonstrated that sleep deprivation impacts respiratory, immune, and cognitive function. Historically, because of the nature of critical illness, sleep has not been considered a priority for patient care in the ICU. More recently, research has demonstrated that sleep is markedly abnormal in patients who are critically ill. In addition, there is often disruption of circadian rhythms. Delirium is a syndrome of acute alteration in mental status that occurs in the setting of contributing factors such as serious illness, medication, and drug or alcohol intoxication or withdrawal. Delirium is a frequent occurrence in critical illness, and research has demonstrated several adverse outcomes associated with delirium including persistent cognitive impairment and increased mortality. Sleep deprivation and delirium share many common symptoms. The similarity in symptoms between sleep disruption and delirium have prompted experts to draw links between the two and question both the relationship and its direction. In addition, the inclusion of sleep disturbance to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition in its constellation of symptoms used in diagnosing delirium has increased awareness of the link between sleep and delirium. This paper will review the literature on sleep in critical illness and the potential mechanisms and pathways that may connect sleep and delirium.

Untreated Relative Hypotension Measured as Perfusion Pressure Deficit During Management of Shock and New-Onset Acute Kidney Injury-A Literature Review

Maintaining an optimal blood pressure (BP) during shock is a fundamental tenet of critical care. Optimal BP targets may be different for different patients. In current practice, too often, uniform BP targets are pursued which may result in inadvertently accepting a degree of untreated relative hypotension, i.e., the deficit between patients' usual premorbid basal BP and the achieved BP, during vasopressor support. Relative hypotension is a common but an under-recognized and an under-treated sign among patients with potential shock state. From a physiological perspective, any relative reduction in the net perfusion pressure across an organ (e.g., renal) vasculature has a potential to overwhelm autoregulatory mechanisms, which are already under stress during shock. Such perfusion pressure deficit may consequently impact organs' ability to function or recover from an injured state. This review discusses such pathophysiologic mechanisms in detail with a particular focus on the risk of new-onset acute kidney injury (AKI). To review current literature, databases of Medline, Embase, and Google scholar were searched to retrieve articles that either adjusted BP targets based on patients' premorbid BP levels or considered relative hypotension as an exposure endpoint and assessed its association with clinical outcomes among acutely ill patients. There were no randomized controlled trials. Only seven studies could be identified and these were reviewed in detail. These studies indicated a significant association between the degree of relative hypotension that was inadvertently accepted in real-world practice and new-onset organ dysfunction or subsequent AKI. However, this is not a high-quality evidence. Therefore, well-designed randomized controlled trials are needed to evaluate whether adoption of individualized BP targets, which are initially guided by patient's premorbid basal BP and then tailored according to clinical response, is superior to conventional BP targets for vasopressor therapy, particularly among patients with vasodilatory shock states.

Pilot study: an intensive care unit sleep promotion protocol

Purpose

Disturbances, such as in-room activity and sound, are significant sources of sleep disruption among critically ill patients. These factors are potentially modifiable. We tested the impact of an intensive care unit (ICU) sleep promotion protocol on overnight in-room disturbance.

Methods

Our protocol restricted non-urgent bedside care from 00:00 to 03:59. Patients were assigned to usual care (n=30) or the sleep protocol (n=26). The primary outcomes were measures of in-room activity, sound and light. These three types of disturbance were compared between arms during a baseline time block (20:00–23:59) and a rest time block (00:00–03:59). We assessed the sleep protocol effect with generalised linear models.

Results

Usual care and sleep protocol patients had equivalent levels of in-room activity, sound and light during the baseline time block (20:00–23:59). In contrast, during the rest time block (00:00–03:59), the sleep protocol arm had 32% fewer room entries (rate ratio (RR) 0.68, p=0.001) and 9.1 fewer minutes of in-room activity (p=0.0002). Also, the length of time between room entrances increased from 26.4 to 45.8 min (p=0.0004). The sleep protocol arm also had lower sound during the rest time block. Mean A-weighted sound was 2.5 decibels lower (p=0.02), and there were 36% fewer peaks (RR 0.64, p=0.02). Light levels were highly variable and not changed by the sleep protocol.

Conclusions

Sleep promotion protocols can improve in-room activity and sound. This provides a better sleep opportunity and may, therefore, improve ICU sleep.

Trial registration number

1112009428

Psychogenic stress in hospitalized veterinary patients: Causation, implications, and therapies

OBJECTIVE

To review the sources, adverse effects, diagnosis, treatment, and prevention of psychogenic stress in hospitalized human and veterinary patients.

DATA SOURCES

Data were collected by searching PubMed for veterinary and human literature from the past 10 years.

HUMAN DATA SYNTHESIS

Psychogenic stress has been linked to immune suppression; gastrointestinal, cardiovascular, and cutaneous diseases; delayed wound healing; alterations in pain perception; and neurologic impairment. Sources of psychogenic stress include environmental alterations such as excessive noise and light, social and physical factors, sleep disruption, drugs, and underlying disease. Nonpharmacologic options for stress reduction include environmental and treatment modifications, music therapy, and early mobilization. Pharmacologic options include sedation with benzodiazepines and dexmedetomidine. Trazodone and melatonin have been examined for use in sleep promotion but are not currently recommended as standard treatments in ICU.

VETERINARY DATA SYNTHESIS

Activation of the stress response in veterinary patients is largely the same as in people, as are the affected body systems. Possible sources of stress can include social, physical, and environmental factors. No gold standard currently exists for the identification and quantification of stress. A combination of physical examination findings and the results of serum biochemistry, CBC, and biomarker testing can be used to support the diagnosis. Stress scales can be implemented to identify stressed patients and assess severity. Nonpharmacologic treatment options include low-stress handling, pheromones, environmental modifications, and sleep promotion. Pharmacologic options include trazodone, benzodiazepines, dexmedetomidine, and melatonin.

CONCLUSION

The prevalence and clinical significance of psychogenic stress in hospitalized veterinary patients is unknown. Future studies are needed to specifically examine the causative factors of psychogenic stress and the effects of various therapies on stress reduction. The recognition and reduction of psychogenic stress in veterinary patients can lead to improvements in patient care and welfare.

Sleep in Hospitalized Patients

Hospitalized patients frequently have disordered and poor-quality sleep due to a variety of both intrinsic and extrinsic factors. These include frequent nighttime intrusions, insomnia related to pain and unfamiliar environments, dark conditions during the day with loss of natural light, and disruption of the natural sleep cycle due to illness. Sleep wake disturbances can result in a deleterious consequence on physical, emotional, and cognitive status, which may impact patient satisfaction, clinical recovery, and hospital length of stay. Despite this, clinicians frequently fail to document sleep disturbances and are generally unaware of the best practices to improve sleep quality in the hospital. A PubMed search was conducted using the terms: ("sleep and hospitalized patients") and ("sleep and hospitalization") to review the published data on the topic of sleep in hospitalized medical patients. The search was limited to English-language articles published between 2000 and 2018. Subsequent PubMed searches were performed to clarify the data described in the initial search, including the terms "hospital sleep protocols," "hospitalized patients sleep documentation," and "hospitalized patients sleep quality". The purpose of this review is to discuss sleep disturbances in hospitalized patients with a focus on causes of sleep disturbance, the effect of poor-quality sleep, high risk populations, considerations for surveillance and prevention, and pharmacologic and non-pharmacologic options for treatment.

Impact of a Nurse Intervention to Improve Sleep Quality in Intensive Care Units: Results From a Randomized Controlled Trial

BACKGROUND

Patients of adult intensive care units (ICUs) often suffer from a lack of sleep. Reducing anxiety by promoting adaptation to the ICU prior to admission may be an appropriate way to increase sleep quality.

OBJECTIVE

The aim of this study was to evaluate the impact on sleep quality of a brief nurse intervention.

METHODS

This was a pilot randomized controlled trial in Spain. Forty patients admitted in hospital for valve cardiac surgery were randomly allocated to (1) control group (n = 20), receiving usual care, and to (2) experimental group (EG, n = 20), receiving a nurse intervention the day before surgery and admission in the ICU. The intervention was based on Roy Adaptation Model. A trained nurse anticipated the stressful stimulus to patients in order to develop functional adaptive behaviors. A set of photographs and videos was used to illustrate the environment and assistance in the ICU. Sleep quality in the ICU was measured with the Richards-Campbell Sleep Questionnaire and usual sleep quality with the Pittsburgh Sleep Quality Index.

RESULTS

After the intervention, sleep quality was lower in the EG compared with the control group (-4 points in Richards-Campbell Sleep Questionnaire, P = .69). Adjustment for main confounders led this reduction to -1.9 points (P = .87) among patients in EG. Stratified analyses shown a positive impact for people who usually slept well (+5.2 points, P = .77), but negative for those who had previous poor sleep quality (-20.0 points, P = .24).

CONCLUSION

A nurse intervention prior to ICU admission did not increase patients' sleep quality. In addition, the intervention could have incremented anxiety over the patients who used to sleep poorly at their homes.

Non-circadian signals in the intensive care unit: Point prevalence morning, noon and night

BACKGROUND

Intensive care unit (ICU) sleep disturbance is severe and potentially related to abnormal light and sound exposure.

OBJECTIVES

To assess the prevalence of measures of light and sound disturbance in ICU patient rooms, and whether these could be modified by a sleep-promotion intervention.

METHODS

This observational study with a before and after design for a quality improvement initiative surveyed environmental factors in ICU rooms at 01:00 08:00, and 12:00. Surveys assessed light usage, television usage, window shade position, and room door/curtain position. Factors were compared before and after an ICU sleep-promotion intervention.

RESULTS

990 (pre-intervention) and 819 (post-intervention) occupied rooms were surveyed. Pre-intervention, the prevalence of night-time factors included: bright lights on (21%), television on (46%), and room door open (94%). Post-intervention, more rooms had all lights off at night (41% v 50%, p = 0.04), and fewer rooms had open door curtains (57% v 42%, p = 0.001) and window shades (78% v 62%, p = 0.002).

CONCLUSIONS

Disruptive environmental factors are common in the ICU. Some factors improve with sleep-promotion interventions.

Sleep Disturbance after Hospitalization and Critical Illness: A Systematic Review

RATIONALE

Sleep disturbance during intensive care unit (ICU) admission is common and severe. Sleep disturbance has been observed in survivors of critical illness even after transfer out of the ICU. Not only is sleep important to overall health and well being, but patients after critical illness are also in a physiologically vulnerable state. Understanding how sleep disturbance impacts recovery from critical illness after hospital discharge is therefore clinically meaningful.

OBJECTIVES

This Systematic Review aimed to summarize studies that identify the prevalence of and risk factors for sleep disturbance after hospital discharge for critical illness survivors.

DATA SOURCES

PubMed (January 4, 2017), MEDLINE (January 4, 2017), and EMBASE (February 1, 2017).

DATA EXTRACTION

Databases were searched for studies of critically ill adult patients after hospital discharge, with sleep disturbance measured as a primary outcome by standardized questionnaire or objective measurement tools. From each relevant study, we extracted prevalence and severity of sleep disturbance at each time point, objective sleep parameters (such as total sleep time, sleep efficiency, and arousal index), and risk factors for sleep disturbance.

SYNTHESIS

A total of 22 studies were identified, with assessment tools including subjective questionnaires, polysomnography, and actigraphy. Subjective questionnaire studies reveal a 50-66.7% (within 1 mo), 34-64.3% (>1-3 mo), 22-57% (>3-6 mo), and 10-61% (>6 mo) prevalence of abnormal sleep after hospital discharge after critical illness. Of the studies assessing multiple time points, four of five questionnaire studies and five of five polysomnography studies show improved aspects of sleep over time. Risk factors for poor sleep varied, but prehospital factors (chronic comorbidity, pre-existing sleep abnormality) and in-hospital factors (severity of acute illness, in-hospital sleep disturbance, pain medication use, and ICU acute stress symptoms) may play a role. Sleep disturbance was frequently associated with postdischarge psychological comorbidities and impaired quality of life.

CONCLUSIONS

Sleep disturbance is common in critically ill patients up to 12 months after hospital discharge. Both subjective and objective studies, however, suggest that sleep disturbance improves over time. More research is needed to understand and optimize sleep in recovery from critical illness.

Validity of a single PTSD checklist item to screen for insomnia in survivors of critical illness

BACKGROUND

There is no insomnia screening tool validated in intensive care unit (ICU) survivors.

OBJECTIVES

To examine the validity of a single item from the PTSD checklist-Civilian version (PCL-C) to detect insomnia by Insomnia Severity Index (ISI) METHODS: We performed a secondary analysis of data from a longitudinal investigation in 120 medical-surgical ICU survivors. At 1 year post-ICU, patients completed ISI, PCL-C, and Medical Short-Form 12 (SF-12) by telephone. A single PCL-C item rates difficulty initiating or maintaining sleep over the past month. We compared performance characteristics of this PCL-C item to ISI-defined insomnia (ISI ≥15).

RESULTS

A score of ≥3 on the PCL-C sleep item exhibited 91% sensitivity and 67% specificity for ISI-defined insomnia (ISI ≥ 15), and it demonstrated construct validity by correlation to related QOL indices.

CONCLUSIONS

A single PCL-C sleep item score ≥ 3 is a reasonable screen to identify insomnia symptoms in ICU survivors.

Creating Naptime: An Overnight, Nonpharmacologic Intensive Care Unit Sleep Promotion Protocol

Introduction:

Patients in the intensive care unit (ICU) have significantly disrupted sleep. Sleep disruption is believed to contribute to ICU delirium, and ICU delirium is associated with increased mortality. Experts recommend sleep promotion as a means of preventing or shortening the duration of delirium. ICU Sleep promotion protocols are highly complex and difficult to implement. Our objective is to describe the development, pilot implementation, and revision of a medical ICU sleep promotion protocol.

Methods:

Naptime is a clustered-care intervention that provides a rest period between 00:00 and 04:00. We used literature review, medical chart review, and stakeholder interviews to identify sources of overnight patient disturbance. With stakeholder input, we developed an initial protocol that we piloted on a small scale. Then, using protocol monitoring and stakeholder feedback, we revised Naptime and adapted it for unitwide implementation.

Results:

We identified sound, patient care, and patient anxiety as important sources of overnight disturbance. The pilot protocol altered the timing of routine care with a focus on medications and laboratory draws. During the pilot, there were frequent protocol violations for laboratory draws and for urgent care. Stakeholder feedback supported revision of the protocol with a focus on providing 60- to 120-minute rest periods interrupted by brief clusters of care between 00:00 and 04:00.

Discussion:

Four-hour blocks of rest may not be possible for all medical ICU patients, but interruptions can be minimized to a significant degree. Involvement of all stakeholders and frequent protocol reevaluation are needed for successful adoption of an overnight rest period.

Effects of music during daytime rest in the intensive care unit

BACKGROUND

Sleep is essential to the recovery of patients in the intensive care unit. Patients in the intensive care unit frequently experience poor sleep, characterized by sleep deprivation, sleep fragmentation and abnormal sleep architecture. Factors affecting sleep are multifactorial.

AIM

To investigate the effects of music on self-reported quality of sleep during daytime rest among patients in the intensive care unit.

STUDY DESIGN

A randomized controlled trial.

METHODS

The study was conducted between February and April 2016 in two Danish multidisciplinary intensive care units. The study sample consisted of 37 patients (19 in the control group and 18 in the intervention group) who complied with the criteria of inclusion for the study. Patients were randomly assigned to either an intervention group or a control group. The intervention group listened to music for 30 min during daytime rest while the control group rested without music. The Richards-Campbell Sleep Questionnaire was used to measure the subjective quality of sleep.

RESULTS

Significant differences in the mean scores of the subjective quality of sleep were found between the intervention group and the control group (p < 0·02). Significant differences were also found between groups in three items of sleep scores: sleep depth (p < 0·02), awakenings (p < 0·00) and the overall perceived quality of sleep (p < 0·01). The perceived noise level score was higher in the intervention group compared with the control group, although not statistically significant (p < 0·67).

CONCLUSION

Listening to music during daytime rest improves subjective sleep in patients in the intensive care unit. Furthermore, there are indications that listening to music reduces the subjective experience of noise in some patients.

RELEVANCE TO CLINICAL PRACTICE

The result of this study implies that music can be an effective practice for nurses to improve sleep among patients in the intensive care unit.

Delivering Prolonged Intensive Care to a Non-human Primate: A High Fidelity Animal Model of Critical Illness

Critical care needs have been rising in recent decades as populations age and comorbidities increase. Sepsis-related admissions to critical care contribute up to 50% of volume and septic shock carries a 35–54% fatality rate. Improvements in sepsis-related care and mortality would have a significant impact of a resource-intensive area of health care delivery. Unfortunately, research has been hampered by the lack of an animal model that replicates the complex care provided to humans in an intensive care unit (ICU). We developed a protocol to provide full ICU type supportive care to Rhesus macaques. This included mechanical ventilation, continuous sedation, fluid and electrolyte management and vasopressor support in response to Ebolavirus-induced septic shock. The animals accurately recapitulated human responses to a full range of ICU interventions (e.g. fluid resuscitation). This model can overcome current animal model limitations by accurately emulating the complexity of ICU care and thereby provide a platform for testing new interventions in critical care and sepsis without placing patients at risk.

Cycles of circadian illuminance are sufficient to entrain and maintain circadian locomotor rhythms in Drosophila

Light at night disrupts the circadian clock and causes serious health problems in the modern world. Here, we show that newly developed four-package light-emitting diodes (LEDs) can provide harmless lighting at night. To quantify the effects of light on the circadian clock, we employed the concept of circadian illuminance (CIL). CIL represents the amount of light weighted toward the wavelengths to which the circadian clock is most sensitive, whereas visual illuminance (VIL) represents the total amount of visible light. Exposure to 12 h:12 h cycles of white LED light with high and low CIL values but a constant VIL value (conditions hereafter referred to as CH/CL) can entrain behavioral and molecular circadian rhythms in flies. Moreover, flies re-entrain to phase shift in the CH/CL cycle. Core-clock proteins are required for the rhythmic behaviors seen with this LED lighting scheme. Taken together, this study provides a guide for designing healthful white LED lights for use at night, and proposes the use of the CIL value for estimating the harmful effects of any light source on organismal health.

The effects of intensive care environment on postoperative nightmare

PURPOSE

We retrospectively investigated the incidence of postoperative nightmares and evaluated the impact of postoperative intensive care on the incidence of during subsequent hospital stay. To reduce the effect of selection bias, we compared the incidence of nightmares in propensity-matched pairs with postoperative management in ICUs or in surgical wards.

METHODS

This is a retrospective review of an institutional registry containing 21,606 anesthesia cases and was conducted with ethics board approval. Outcomes of surgical patients treated in ICUs and in postsurgical wards (ICU admission vs non ICU admission) were compared first for nightmares using the initial 12,508 patients. To avoid channeling bias, propensity score analysis was used to generate a set of matched cases (ICU admission) and controls (non ICU admission), yielding 642 matched patient pairs. The incidence rate of nightmares was compared as the primary outcome.

RESULTS

Before adjusting patients' characteristics, ICU environment exposure increased the incidence of nightmares compared with non-ICU environment during subsequent hospital stay [ICU vs non-ICU: 101/718 (12.3 %) vs 1147/10,542 (9.81 %)]. The odds ratio (95 % CIs) for ICU was 1.29 (1.03-1.61) for nightmares (p = 0.022). After propensity score matching, however, an equal rate of nightmares occurred in the ICU environment exposure compared to the non-ICU environment [ICU vs non-ICU: 81/561 (12.6 %) vs 73/569 (11.4 %)]. The odds ratio and 95 % CIs for ICU were 1.13 (0.80-1.58) for nightmares (p = 0.54).

CONCLUSIONS

The incidence of nightmares did not become more evident during subsequent hospital stay after ICU environment exposure.

Comparing average levels and peak occurrence of overnight sound in the medical intensive care unit on A-weighted and C-weighted decibel scales

PURPOSE

Sound levels in the intensive care unit (ICU) are universally elevated and are believed to contribute to sleep and circadian disruption. The purpose of this study is to compare overnight ICU sound levels and peak occurrence on A- vs C-weighted scales.

MATERIALS AND METHODS

This was a prospective observational study of overnight sound levels in 59 medical ICU patient rooms. Sound level was recorded every 10 seconds on A- and C-weighted decibel scales. Equivalent sound level (Leq) and sound peaks were reported for full and partial night periods.

RESULTS

The overnight A-weighted Leq of 53.6 dBA was well above World Health Organization recommendations; overnight C-weighted Leq was 63.1 dBC (no World Health Organization recommendations). Peak sound occurrence ranged from 1.8 to 23.3 times per hour. Illness severity, mechanical ventilation, and delirium were not associated with Leq or peak occurrence. Equivalent sound level and peak measures for A- and C-weighted decibel scales were significantly different from each other.

CONCLUSIONS

Sound levels in the medical ICU are high throughout the night. Patient factors were not associated with Leq or peak occurrence. Significant discordance between A- and C-weighted values suggests that low-frequency sound is a meaningful factor in the medical ICU environment.

Sleep Disturbances and Critical Illness

Sleep disturbances are common in the intensive care unit setting. This article describes the causal factors associated with alterations in sleep in the intensive care setting, effects of sleep disturbances for patients, and strategies to mitigate sleep disturbances. A review of normal sleep architecture is provided, as is a discussion of the methods of measuring sleep in the critical care setting.