Dynamic prevalence of sleep disturbance among critically ill patients in intensive care units and after hospitalisation: A systematic review and meta-analysis

BackgroundSleep disturbance is a common complaint among critically ill patients in intensive care units and after hospitalisation. However, the prevalence of sleep disturbance among critically ill patients varies widely.ObjectiveTo estimate the prevalence of sleep disturbance among critically ill patients in the intensive care unit and after hospitalisation.MethodsElectronic databases were searched from their inception until 15 August 2022. Only observational studies with cross-sectional, prospective, and retrospective designs investigating sleep disturbance prevalence among critically ill adults (aged ≥ 18 years) during intensive care unit stay and after hospitalisation were included.ResultsWe found 13 studies investigating sleep disturbance prevalence in intensive care units and 14 investigating sleep disturbance prevalence after hospitalisation, with 1,228 and 3,065 participants, respectively. The prevalence of sleep disturbance during an ICU stay was 66 %, and at two, three, six and ≥ 12 months after hospitalisation was 64 %, 49 %, 40 %, and 28 %, respectively. Studies using the Richards–Campbell Sleep Questionnaire detected a higher prevalence of sleep disturbance among patients in intensive care units than non-intensive care unit specific questionnaires; studies reported comparable sleep disturbance prevalence during intensive care stays for patients with and without mechanical ventilation.ConclusionSleep disturbance is prevalent in critically ill patients admitted to an intensive care unit and persists for up to one year after hospitalisation, with prevalence ranging from 28 % to 66 %. The study results highlight the importance of implementing effective interventions as early as possible to improve intensive care unit sleep quality.     

The accuracy of simple,feasible alternatives to polysomnography for assessing sleep in intensive care: An observational study

BackgroundSleep disturbance is common in intensive care patients. Understanding the accuracy of simple, feasible sleep measurement techniques is essential to informing their possible role in usual clinical care.ObjectiveThe aim of the study was to investigate whether sleep monitoring techniques such as actigraphy (ACTG), behavioural assessments, and patient surveys are comparable with polysomnography (PSG) in accurately reporting sleep quantity and quality among conscious, intensive care patients.MethodsAn observational study was conducted in 20 patients admitted to the intensive care unit (ICU) for a minimum duration of 24 h, who underwent concurrent sleep monitoring via PSG, ACTG, nursing-based observations, and self-reported assessment using the Richards–Campbell Sleep Questionnaire.ResultsThe reported total sleep time (TST) for the 20 participants measured by PSG was 328.2 min (±106 min) compared with ACTG (362.4 min [±62.1 min]; mean difference = 34.22 min [±129 min]). Bland–Altman analysis indicated that PSG and ACTG demonstrated clinical agreement and did not perform differently across a number of sleep variables including TST, awakening, sleep-onset latency, and sleep efficiency. Nursing observations overestimated sleep duration compared to PSG TST (mean difference = 9.95 ± 136.3 min, p > 0.05), and patient-reported TST was underestimated compared to PSG TST (mean difference = −51.81 ± 144.1 7, p > 0.05).ConclusionsAmongst conscious patients treated in the ICU, sleep characteristics measured by ACTG were similar to those measured by PSG. ACTG may provide a clinically feasible and acceptable proxy approach to sleep monitoring in conscious ICU patients.     

Clinical review: Sleep measurement in critical care patients: research and clinical implications

Sleep disturbances are common in critically ill patients and have been characterised by numerous studies using polysomnography. Issues regarding patient populations, monitoring duration and timing (nocturnal versus continuous), as well as practical problems encountered in critical care studies using polysomnography are considered with regard to future interventional studies on sleep. Polysomnography is the gold standard in objectively measuring the quality and quantity of sleep. However, it is difficult to undertake, particularly in patients recovering from critical illness in an acute-care area. Therefore, other objective (actigraphy and bispectral index) and subjective (nurse or patient assessment) methods have been used in other critical care studies. Each of these techniques has its own particular advantages and disadvantages. We use data from an interventional study to compare agreement between four of these alternative techniques in the measurement of nocturnal sleep quantity. Recommendations for further developments in sleep monitoring techniques for research and clinical application are made. Also, methodological problems in studies validating various sleep measurement techniques are explored. Trial registration: Current Controlled Trials ISRCTN47578325.     

Sleep–wake activity rhythm and health‐related quality of life among patients with coronary artery disease and in a population‐based sample—An actigraphy and questionnaire study

The aim of this study was to explore whether there are gender differences in sleep and health‐related quality of life in patients with coronary artery disease (CAD) and a matched population‐based sample and to see how subjectively rated sleep is associated with actigraphy. Secondly, to explore whether factors that predict patients' sleep quality could be identified. Fifty‐seven patients with stable CAD and 47 participants from a population‐based sample were included. All participants completed the Uppsala Sleep Inventory (USI), the Epworth Sleepiness Scale and the SF‐36. Actigraphy recordings and a sleep diary were performed for seven 24‐h periods. Multiple stepwise regression analysis showed that sleep duration, sleep onset latency, nocturnal awakenings, vitality (SF‐36) and body mass index explained 60% of the sleep quality outcome (USI). Sleep duration, sleep efficiency and fragmentation index assessed with actigraphy and sleep diary accounted for 36% of the sleep quality outcome (diary). The result can form the basis for a non‐pharmacological, self‐care programme supported and led by nurses.     

Sleep disruption in the intensive care unit

Subjective and objective measures of sleep quality indicate that the sleep of patients in the intensive care unit (ICU) is extraordinarily disturbed. Several studies spanning the past two decades have demonstrated that critically ill patients exhibit reduced sleep efficiency, reduced restorative sleep, and frequent arousals and awakenings. A number of potential sleep disrupters exist in the ICU environment, with noise being the predominant focus of investigation. Excessive noise levels in the ICU correlate with poor sleep quality in healthy subjects and patients. Medications, light, and frequent care-related activities can also interfere with a patient's ability to obtain good-quality sleep. Sleep disruption can have significant adverse consequences for critically ill patients, such as immune system compromise and respiratory abnormalities. Although several questions remain unanswered, including the impact of sleep disruption on the clinical outcome of patients in the ICU, there is a growing interest in developing new strategies to improve sleep quality.     

Repeated sleep‐quality assessment and use of sleep‐promoting interventions in ICU

To describe sleep quality using repeated subjective assessment and the ongoing use of sleep‐promoting interventions in intensive care. It is well known that the critically ill experience sleep disruption while receiving treatment in the intensive care unit. Both the measurement and promotion of sleep is challenging in the complex environment of intensive care unit. Repeated subjective assessment of patients' sleep in the intensive care unit and use of sleep‐promoting interventions has not been widely reported. An observational study was conducted in a 58‐bed adult intensive care unit. Sleep quality was assessed using the Richards‐Campbell Sleep Questionnaire (RCSQ) each morning. intensive care unit audit sleep‐promoting intervention data were compared to data obtained prior to the implementation of a sleep guideline. Patients answered open‐ended questions about the facilitators and deterrents of their sleep in intensive care unit. The sample (n = 50) was predominately male (76%) with a mean age: 62.6±16.9 years. Sleep quality was assessed on 2 days or more for 21 patients. The majority of patients (98%) received sleep‐promoting interventions. Sleep quality had not improved significantly since the guideline was first implemented. The mean Richards‐Campbell Sleep Questionnaire score was 47.9±24.1 mm. The main sleep deterrents were discomfort and noise. Frequently cited facilitators were nothing (i.e. nothing helped) and analgesia. The Richards‐Campbell Sleep Questionnaire was used on repeated occasions, and sleep‐promoting interventions were used extensively. There was no evidence of improvement in sleep quality since the implementation of a sleep guideline. The use of the Richards‐Campbell Sleep Questionnaire for the subjective self‐assessment of sleep quality in intensive care unit patients and the implementation of simple‐promoting interventions by intensive care unit clinicians is both feasible and may be the most practical way to assess sleep in the intensive care unit context.     

Measurement of sleep in critically ill patients

Research to evaluate interventions to promote sleep in critically ill patients has been restricted by the lack of brief, inexpensive outcome measures. This article describes the development and testing of an instrument to measure sleep in critically ill patients. A convenience sample of 70 alert, oriented, critically ill males was studied using polysomnography (PSG), the gold standard for sleep measurement, for one night. In the morning the patients completed the Richards-Campbell Sleep Questionnaire (RCSQ), a five-item visual analog scale. Internal consistency reliability of the RCSQ was .90 and principal components factor analysis revealed a single factor (Eigenvalue = 3.61, percent variance = 72.2). The RCSQ total score accounted for approximately 33% of the variance in the PSG indicator sleep efficiency index (p < .001). The data provide support for the reliability and validity of the RCSQ.     

Investigation of sleep disturbance in chronic low back pain: an age- and gender-matched case-control study over a 7-night period

Sleep disturbance is frequently reported by people with chronic low back pain (>12 weeks; CLBP), but few studies have comprehensively investigated sleep in this population. This study investigated differences in subjectively and objectively measured sleep patterns of people with CLBP, and compared this to age- and gender matched controls. Thirty-two consenting participants (n = 16 with CLBP, n = 16 matched controls), aged 24–65 years (43.8% male) underwent an interview regarding sleep influencing variables, completed the Pittsburgh Sleep Quality Index, Insomnia Severity Index, Pittsburgh Sleep Diary, SF36-v2, Hospital Anxiety and Depression Scale, Oswestry Disability Index, Numerical Pain Rating Scales, and underwent seven consecutive nights of actigraphic measurement in the home environment. Compared to controls, people with CLBP had, on self-report measures, significantly poorer sleep quality [Pittsburgh Sleep Quality Index (range 0–21) mean (SD) 10.9 (4.2)], clinical insomnia [Insomnia Severity Index mean (range 0–28) 13.7 (7.6)], lower sleep efficiency, longer sleep onset latency, more time awake after sleep onset, and more awakenings during sleep (p < 0.05). However, no significant differences between groups were found on objective actigraphy (p > 0.05). The findings provide some evidence to support self-reported sleep assessment as an outcome measure in CLBP research, while further research is needed to determine the validity of objective sleep measurement in this population.     

Sleep continuity: a new metric to quantify disrupted hypnograms in non-sedated intensive care unit patients

Introduction

Sleep in intensive care unit (ICU) patients is severely altered. In a large proportion of critically ill patients, conventional sleep electroencephalogram (EEG) patterns are replaced by atypical sleep. On the other hand, some non-sedated patients can display usual sleep EEG patterns. In the latter, sleep is highly fragmented and disrupted and conventional rules may not be optimal. We sought to determine whether sleep continuity could be a useful metric to quantify the amount of sleep with recuperative function in critically ill patients with usual sleep EEG features.

Methods

We retrospectively reanalyzed polysomnographies recorded in non-sedated critically ill patients requiring non-invasive ventilation (NIV) for acute hypercapnic respiratory failure. Using conventional rules, we built two-state hypnograms (sleep and wake) and identified all sleep episodes. The percentage of time spent in sleep bouts (<10 minutes), short naps (>10 and <30 minutes) and long naps (>30 minutes) was used to describe sleep continuity. In a first study, we compared these measures regarding good (NIV success) or poor outcome (NIV failure). In a second study performed on a different patient group, we compared these measurements during NIV and during spontaneous breathing.

Results

While fragmentation indices were similar in the two groups, the percentage of total sleep time spent in short naps was higher and the percentage of sleep time spent in sleep bouts was lower in patients with successful NIV. The percentage of total sleep time spent in long naps was higher and the percentage of sleep time spent in sleep bouts was lower during NIV than during spontaneous breathing; the level of reproducibility of sleep continuity measures between scorers was high.

Conclusions

Sleep continuity measurements could constitute a clinically relevant and reproducible assessment of sleep disruption in non-sedated ICU patients with usual sleep EEG.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0628-4) contains supplementary material, which is available to authorized users.     

Sleep and nursing care activities in an intensive care unit

This study aimed to describe the quality of sleep of non‐intubated patients and the night‐time nursing care activities in an intensive care unit. The study also aimed to evaluate the effect of nursing care activities on the quality of sleep. An overnight polysomnography was performed in 21 alert, non‐intubated, non‐sedated adult patients, and all nursing care activities that involved touching the patient were documented by the bedside nurse. The median (interquartile range) amount of sleep was 387 (170, 486) minutes. The portion of deep non‐rapid‐eye‐movement (non‐REM) sleep varied from 0% to 42% and REM sleep from 0% to 65%. The frequency of arousals and awakenings varied from two to 73 per hour. The median amount of nursing care activities was 0.6/h. Every tenth activity presumably awakened the patient. Patients who had more care activities had more light N1 sleep, less light N2 sleep, and less deep sleep. Nursing care was often performed while patients were awake. However, only 31% of the intervals between nursing care activities were over 90 min. More attention should be paid to better clustering of care activities.     

Effect of virtual reality meditation on sleep quality of intensive care unit patients: A randomised controlled trial

ObjectiveThis study aimed to investigate the effect of virtual reality meditation on sleep quality of intensive care unit patients.MethodsThis randomised controlled trial included 48 cardiac intensive care unit patients in a university hospital in Korea randomly allocated to the experimental (24) and the control group (24). For the experimental group, meditation was provided for 30 minutes using a head-mounted display for virtual reality, on the evening of the admission day.Main outcome measuresThe sleep quality of both groups was measured by self-report using Sleep Scale A and the activity tracker FitBit Charge 2.ResultsThe experimental group reported significantly higher subjective sleep quality than did the control group. Activity tracker assessment indicated that total sleep time and light sleep time did not differ between the groups. However, the awake time was shorter, deep sleep time was longer and sleep efficiency was significantly higher in the experimental group than in the control group.ConclusionVirtual reality meditation positively affected the sleep quality of intensive care unit patients. Critical care nurses should consider using virtual reality meditation as a nursing intervention to improve the patient’s sleep quality.     

神经外科监护室标准化交接班流程的设计与应用

目的:探讨标准化流程在神经外科ICU护士床边交接班中的应用效果。方法:2012年7~12月采用标准化床边交接班流程,规范神经外科重症监护室患者交接班过程。将实施后的交接班问题发生率、护士交接班满意度与实施前进行回顾性对比分析。结果:应用标准化床边交接班流程后,危重患者交接班的问题发生率由原来的20.09%降低至5.26%,交接双方护理人员的满意度平均得分由原来的(86.83±3.90)分提高到(95.25±3.28)分,经比较均有统计学意义(P0.05)。结论:标准化床边交接班流程避免了交接班遗漏,规范了患者转出交接流程,提高了护理工作效率,保证了重症患者连续性护理质量,保证了患者安全,促进了团队协作。     

Sleep in the intensive care unit

Abnormalities of sleep are extremely common in critically ill patients, but the mechanisms are poorly understood. About half of total sleep time occurs during the daytime, and circadian rhythm is markedly diminished or lost. Judgments based on inspection consistently overestimate sleep time and do not detect sleep disruption. Accordingly, reliable polygraphic recordings are needed to measure sleep quantity and quality in critically ill patients. Critically ill patients exhibit more frequent arousals and awakenings than is normal, and decreases in rapid eye movement and slow wave sleep. The degree of sleep fragmentation is at least equivalent to that seen in patients with obstructive sleep apnea. About 20% of arousals and awakenings are related to noise, 10% are related to patient care activities, and the cause for the remainder is not known; severity of underlying disease is likely an important factor. Mechanical ventilation can cause sleep disruption, but the precise mechanism has not been defined. Sleep disruption can induce sympathetic activation and elevation of blood pressure, which may contribute to patient morbidity. In healthy subjects, sleep deprivation can decrease immune function and promote negative nitrogen balance. Measures to improve the quantity and quality of sleep in critically ill patients include careful attention to mode of mechanical ventilation, decreasing noise, and sedative agents (although the latter are double-edged swords).     

Bench-to-bedside review: Delirium in ICU patients - importance of sleep deprivation

Delirium occurs frequently in critically ill patients and has been associated with both short-term and long-term consequences. Efforts to decrease delirium prevalence have been directed at identifying and modifying its risk factors. One potentially modifiable risk factor is sleep deprivation. Critically ill patients are known to experience poor sleep quality with severe sleep fragmentation and disruption of sleep architecture. Poor sleep while in the intensive care unit is one of the most common complaints of patients who survive critical illness. The relationship between delirium and sleep deprivation remains controversial. However, studies have demonstrated many similarities between the clinical and physiologic profiles of patients with delirium and sleep deprivation. This article aims to review the literature, the clinical and neurobiologic consequences of sleep deprivation, and the potential relationship between sleep deprivation and delirium in intensive care unit patients. Sleep deprivation may prove to be a modifiable risk factor for the development of delirium with important implications for the acute and long-term outcome of critically ill patients.     

Factors affecting sleep in the critically ill: An observational study

Purpose

The aims of the current study were to describe the extrinsic and intrinsic factors affecting sleep in critically ill patients and to examine potential relationships with sleep quality.

Materials and Methods

Sleep was recorded using polysomnography (PSG) and self-reports collected in adult patients in intensive care. Sound and illuminance levels were recorded during sleep recording. Objective sleep quality was quantified using total sleep time divided by the number of sleep periods (PSG sleep period time ratio). A regression model was specified using the “PSG sleep period time ratio” as a dependent variable.

Results

Sleep was highly fragmented. Patients rated noise and light as the most sleep disruptive. Continuous equivalent sound levels were 56 dB (A). Median daytime illuminance level was 74 lux, and nighttime levels were 1 lux. The regression model explained 25% of the variance in sleep quality (P = .027); the presence of an artificial airway was the only statistically significant predictor in the model (P = .007).

Conclusions

The presence of an artificial airway during sleep monitoring was the only significant predictor in the regression model and may suggest that although potentially uncomfortable, an artificial airway may actually promote sleep. This requires further investigation.     

体动仪的临床应用

体动仪的应用始于20世纪70年代,是一种可以记录一段时间内身体活动的穿戴式设备,可计算睡眠、能量消耗等诸多参数。与传统多导睡眠监测相比,体动仪有着独特的优势。本文从体动仪的特点,使用中的注意事项,数据分析,临床应用等方面介绍了目前体动仪发展概况,并针对现有问题和不足进行了探讨。供睡眠医学相关临床工作人员和相关技术工程领域专业人士参考。     

The effect of earplugs on sleep measures during exposure to simulated intensive care unit noise.

BACKGROUND: Sleep deprivation may contribute to impaired immune function, ventilatory compromise, disrupted thermoregulation, and delirium. Noise levels in intensive care units may be related to disturbed sleep patterns, but noise reduction has not been tested in this setting. OBJECTIVE: To measure the effect of a noise reduction intervention on the sleep of healthy subjects exposed to simulated intensive care unit noise. METHODS: After digital audiotape recording of noise and development of the noise reduction intervention, 5 nocturnal 8-hour periods of sleep were measured in 6 paid, healthy volunteers at 7-day intervals in a sleep disorders center. Polysomnographic data were collected by experienced sleep disorders technicians and scored by certified raters. After the first 3 quiet nights, earplugs were randomly assigned to be worn on the fourth and fifth nights during exposure to the recorded noise. Sound pressure levels were measured during all 5 nights. RESULTS: Sleep architecture and sound measurements on quiet nights did not differ significantly. Sound levels were significantly lower on quiet nights than on noise nights. Exposure to the noise increased the number of awakenings, percentage of stage 2 sleep, and rapid eye movement latency and decreased time asleep, sleep maintenance efficiency index, and percentage of rapid eye movement sleep. Earplugs worn during exposure to the noise produced a significant decrease in rapid eye movement latency and an increase in the percentage of rapid eye movement sleep. CONCLUSION: The results provide a reasonable basis for testing the effects of earplugs on the sleep of critically ill subjects.     

Sleep disturbances and fatigue in critically ill patients

Sleep disturbances and fatigue are significant problems for critically ill patients. Existing sleep disorders, underlying medical/surgical conditions, environmental factors, stress, medications, and other treatments all contribute to a patient's inability to sleep. Sleep disturbance and debilitating fatigue that originate during acute illness may continue months after discharge from intensive care units (ICUs). If these issues are unrecognized, lack of treatment may contribute to chronic sleep problems, impaired quality of life, and incomplete rehabilitation. A multidisciplinary approach that incorporates assessment of sleep disturbances and fatigue, environmental controls, appropriate pharmacologic management, and educational and behavioral interventions is necessary to reduce the impact of sleep disturbances and fatigue in ICU patients. Nurses are well positioned to identify issues in their own units that prevent effective patient sleep. This article will discuss the literature related to the occurrence, etiology, and risk factors of sleep disturbance and fatigue and describe assessment and management options in critically ill adults.     

Effects of propofol on sleep quality in mechanically ventilated critically ill patients: a physiological study

Purpose

To access the effect of propofol administration on sleep quality in critically ill patients ventilated on assisted modes.

Methods

This was a randomized crossover physiological study conducted in an adult ICU at a tertiary hospital. Two nights’ polysomnography was performed in mechanically ventilated critically ill patients with and without propofol infusion, while respiratory variables were continuously recorded. Arterial blood gasses were measured in the beginning and at the end of the study. The rate of propofol infusion was adjusted to maintain a sedation level of 3 on the Ramsay scale. Sleep architecture was analyzed manually using predetermined criteria. Patient–ventilator asynchrony was evaluated breath by breath using the flow–time and airway pressure–time waveforms.

Results

Twelve patients were studied. Respiratory variables, patient–ventilator asynchrony, and arterial blood gasses did not differ between experimental conditions. With or without propofol all patients demonstrated abnormal sleep architecture, expressed by lack of sequential progression through sleep stages and their abnormal distribution. Sleep efficiency, sleep fragmentation, and sleep stage distribution (1, 2, and slow wave) did not differ with or without propofol. Compared to without propofol, both the number of patients exhibiting REM sleep (p?=?0.02) and the percentage of REM sleep (p?=?0.04) decreased significantly with propofol.

Conclusions

In critically ill patients ventilated on assisted modes, propofol administration to achieve the recommended level of sedation suppresses the REM sleep stage and further worsens the poor sleep quality of these patients.