Polysomnography in acutely ill intensive care unit patients

Clinical Practice Guidelines for the Prevention and Management of Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU

OBJECTIVE

To update and expand the 2013 Clinical Practice Guidelines for the Management of Pain, Agitation, and Delirium in Adult Patients in the ICU.

DESIGN

Thirty-two international experts, four methodologists, and four critical illness survivors met virtually at least monthly. All section groups gathered face-to-face at annual Society of Critical Care Medicine congresses; virtual connections included those unable to attend. A formal conflict of interest policy was developed a priori and enforced throughout the process. Teleconferences and electronic discussions among subgroups and whole panel were part of the guidelines' development. A general content review was completed face-to-face by all panel members in January 2017.

METHODS

Content experts, methodologists, and ICU survivors were represented in each of the five sections of the guidelines: Pain, Agitation/sedation, Delirium, Immobility (mobilization/rehabilitation), and Sleep (disruption). Each section created Population, Intervention, Comparison, and Outcome, and nonactionable, descriptive questions based on perceived clinical relevance. The guideline group then voted their ranking, and patients prioritized their importance. For each Population, Intervention, Comparison, and Outcome question, sections searched the best available evidence, determined its quality, and formulated recommendations as "strong," "conditional," or "good" practice statements based on Grading of Recommendations Assessment, Development and Evaluation principles. In addition, evidence gaps and clinical caveats were explicitly identified.

RESULTS

The Pain, Agitation/Sedation, Delirium, Immobility (mobilization/rehabilitation), and Sleep (disruption) panel issued 37 recommendations (three strong and 34 conditional), two good practice statements, and 32 ungraded, nonactionable statements. Three questions from the patient-centered prioritized question list remained without recommendation.

CONCLUSIONS

We found substantial agreement among a large, interdisciplinary cohort of international experts regarding evidence supporting recommendations, and the remaining literature gaps in the assessment, prevention, and treatment of Pain, Agitation/sedation, Delirium, Immobility (mobilization/rehabilitation), and Sleep (disruption) in critically ill adults. Highlighting this evidence and the research needs will improve Pain, Agitation/sedation, Delirium, Immobility (mobilization/rehabilitation), and Sleep (disruption) management and provide the foundation for improved outcomes and science in this vulnerable population.

Bed Rest and Hypoxic Exposure Affect Sleep Architecture and Breathing Stability

Objective: Despite over 50 years of research on the physiological effects of sustained bed rest, data characterizing its effects on sleep macrostructure and breathing stability in humans are scarce. This study was conducted to determine the effects of continuous exposure to hypoxia and sustained best rest, both individually and combined, on nocturnal sleep and breathing stability.

Methods: Eleven participants completed three randomized, counter-balanced, 21-days trials of: (1) normoxic bed rest (NBR, P_IO₂ = 133.1 ± 0.3), (2) hypoxic ambulatory confinement (HAMB, P_IO₂ = 90.0 ± 0.4) and (3) hypoxic bed rest (HBR, P_IO₂ = 90.0 ± 0.4; ~4,000 m equivalent altitude). Full objective polysomnography was performed at baseline, on Night 1 and Night 21 in each condition.

Results: In NBR Night 1, more time was spent in light sleep (10 ± 2%) compared to baseline (8 ± 2%; p = 0.028); Slow-wave sleep (SWS) was reduced from baseline in the hypoxic-only trial by 18% (HAMB Night 21, p = 0.028) and further reduced by 33% (HBR Night 1, p = 0.010), and 36% (HBR Night 21, p = 0.008) when combined with bed rest. The apnea-hypopnea index doubled from Night 1 to Night 21 in HBR (32–62 events·h⁻¹) and HAMB (31–59 events·h⁻¹; p = 0.002). Those who experienced greatest breathing instability from Night 1 to Night 21 (NBR) were correlated to unchanged or higher (+1%) night SpO₂ concentrations (R² = 0.471, p = 0.020).

Conclusion: Bed rest negatively affects sleep macrostructure, increases the apnea-hypopnea index, and worsens breathing stability, each independently exacerbated by continuous exposure to hypoxia.

Surgical Intensive Care Unit Optimal Mobilisation Score (SOMS) trial: a protocol for an international, multicentre, randomised controlled trial focused on goal-directed early mobilisation of surgical ICU patients

INTRODUCTION

Immobilisation in the intensive care unit (ICU) leads to muscle weakness and is associated with increased costs and long-term functional disability. Previous studies showed early mobilisation of medical ICU patients improves clinical outcomes. The Surgical ICU Optimal Mobilisation Score (SOMS) trial aims to test whether a budget-neutral intervention to facilitate goal-directed early mobilisation in the surgical ICU improves participant mobilisation and associated clinical outcomes.

METHODS AND ANALYSIS

The SOMS trial is an international, multicentre, randomised clinical study being conducted in the USA and Europe. We are targeting 200 patients. The primary outcome is average daily SOMS level and key secondary outcomes are ICU length of stay until discharge readiness and 'mini' modified Functional Independence Measure (mmFIM) at hospital discharge. Additional secondary outcomes include quality of life assessed at 3 months after hospital discharge and global muscle strength at ICU discharge. Exploratory outcomes will include: ventilator-free days, ICU and hospital length of stay and 3-month mortality. We will explore genetic influences on the effectiveness of early mobilisation and centre-specific effects of early mobilisation on outcomes.

ETHICS AND DISSEMINATION

Following Institutional Review Board (IRB) approval in three institutions, we started study recruitment and plan to expand to additional centres in Germany and Italy. Safety monitoring will be the domain of the Data and Safety Monitoring Board (DSMB). The SOMS trial will also explore the feasibility of a transcontinental study on early mobilisation in the surgical ICU.

RESULTS

The results of this study, along with those of ancillary studies, will be made available in the form of manuscripts and presentations at national and international meetings.

REGISTRATION

This study has been registered at clinicaltrials.gov (NCT01363102).

[Quality of sleep in patients hospitalized in an intensive care unit]

INTRODUCTION

Trouble sleeping is common in the elderly population and is attributed to changes that aging brings in the sleep architecture and circadian rhythm. The prevalence of insomnia shows a marked increase with advancing age, in a proportion of 14 to 32% among those over 65 years. If we add these physiological changes of sleep with those found in patients admitted to the Intensive Care Unit (ICU), the problem worsens. The prevalence of these disorders in these units is from 22 - 61%. Sleep deprivation may contribute to worsening of the patients. The main objective is to describe the quality of sleep of patients admitted to the Coronary ICU of the Hospital Miguel Servet and the environmental factors that contribute to these disorders.

MATERIAL AND METHODS

A total of 75 conscious and oriented patients in the Coronary ICU Hospital Miguel Servet were included. Data was collected between February 17 and April 30, 2011. The subjects were asked to state if they had slept well by means of a survey and to score the environmental factors that may have bothered them.

RESULTS AND DISCUSSION

Most patients said they had slept well (66.7%). Noise was the environmental factor that bothered them most. In analyzing the different noises, patients identified hearing people talking as being the most annoying.

CONCLUSION

Changes must be implemented in the unit that would favor restful sleep.

Factors affecting sleep quality of patients in intensive care unit

INTRODUCTION

Sleep disturbance is a frequently overlooked complication of intensive care unit (ICU) stay.

AIM

To evaluate sleep quality among patients admitted to ICU and investigate environmental and non-environmental factors that affect sleep quality in ICU.

METHODS

Over a 22-month period, we consecutively recruited patients who spent ≥ 2 nights post-endotracheal extubation in ICU and who were orientated to time, place, and person on the day of discharge. Self-reported sleep quality, according to a modified Freedman questionnaire, which provided data on self-reported ICU sleep quality in ICU and environmental factors affecting sleep quality in the ICU, were collected. We also investigated non-environmental factors, such as severity of illness, ICU interventions, and medications that can affect sleep quality.

RESULTS

Fifty males and 50 females were recruited with a mean (± SD) age of 65.1 ± 15.2 years. APACHE II score at admission to ICU was 18.1 ± 7.5 with duration of stay 6.7 ± 6.5days. Self-reported sleep quality score at home (1 = worst; 10 = best) was 7.0 ± 2.2; this decreased to 4.0 ± 1.7 during their stay in ICU (p < 0.001). In multivariate analysis with APACHE III as severity of illness (R(2) = 0.25), factors [exp(b)(95% CI), p value] which significantly affected sleep in ICU were sex [0.37(0.19-0.72), p < 0.01], age and sex interaction [1.02(1.01-1.03), p < 0.01], bedside phone [0.92(0.87-0.97), p < 0.01], prior quality of sleep at home [1.30(1.05-1.62), p = 0.02], and use of steroids [0.82(0.69-0.98), p = 0.03] during the stay in ICU.

CONCLUSION

Reduced sleep quality is a common problem in ICU with a multifactorial etiology.

[Acute hypercapnic respiratory failure in patients with sleep apneas]

INTRODUCTION

Acute hypercapnic respiratory failure (AHRF) is a serious condition observed in some patients with sleep apnea-hypopnea syndrome (SAHS). The objective of the present study was to study the clinical characteristics of SAHS patients who develop AHRF and their prognosis.

PATIENTS AND METHOD

A total of 70 consecutive SAHS patients who survived an AHRF episode and 70 SAHS patients paired by age with no previous history of AHRF were prospectively studied and followed up for 3 years.

RESULTS

The deterioration of lung function due to obesity or concomitant chronic obstructive pulmonary diseases (COPD) was common in SAHS patients with AHRF. In the multivariate analysis, the risk factors associated with AHRF were baseline PaO(2,) the theoretical percentage value of the forced vital capacity, alcohol consumption, and benzodiazepines. The mortality during follow up was higher among patients who had AHRF than in the control group. The main cause of death was respiratory, and the coexistence of COPD was identified as a mortality risk factor.

CONCLUSIONS

The development of AHRF in SAHS patients is associated with a deterioration in lung function and with alcohol and benzodiazepine consumption. The patients had a higher mortality after the AHRF episode, mainly a respiratory cause. New studies are required that evaluate the different available therapeutic options in these patients.

Sleep in the ICU: potential mechanisms and clinical implications

Patients in the ICU are known to have severely disrupted sleep with disturbed circadian pattern, decreased nocturnal sleep time, abnormally increased stages 1 and 2 sleep, and reduced or absent deep sleep. Recent data reveal that a subpopulation of critically ill patients manifests unique EEG sleep patterns. The etiology of sleep disruption in the ICU includes the inherent nature of the environment, medications, ventilator-patient interaction, and the effect of acute illness. How sleep disruption contributes to outcomes in critically ill patients, such as recovery time and weaning from mechanical ventilation, is unknown. This article reviews the literature describing sleep in ICU patients, including recent investigations in patients who require mechanical ventilation, factors that affect sleep in critically ill patients, and the potential mechanisms and clinical implications of disturbed sleep in the ICU setting with directions to consider for future investigations.

Adverse effects of sleep deprivation in the ICU

The hospital is not conducive to sleep. Patients in the ICU are particularly susceptible to sleep disruption secondary to environmental and medical issues. Despite the frequency of sleep disruption in the ICU, the quality of critically ill patients' sleep is often overlooked. This article discusses the following issues essential to understanding the factors associated with sleep loss in the ICU: (1) core elements to consider from the baseline sleep history, (2) impact of the ICU environment on the ICU patient's sleep pattern, and (3) overall systematic impact of sleep deprivation on the ICU patient.

Moving beyond empiric continuous positive airway pressure (CPAP) trials for central sleep apnea: a multi-modality titration study

There is no universally accepted method to determine effective therapy for central sleep apnea (CSA). Continuous positive airway pressure (CPAP) applied acutely most often does not eliminate apneas and hypopneas. We hypothesized that the application of two or more therapeutic modalities after the diagnostic phase of polysomnography, a multi-modality titration study (MMTS), would identify a successful CSA treatment more often than a standard split-night study (SNS) and obviate the need for additional polysomnograms to determine a successful therapy. We retrospectively analyzed polysomnograms of patients diagnosed with CSA at our Sleep Disorders Center. We defined a therapy trial that resulted in an apnea-hypopnea index < 10 with at least one treatment modality as a therapeutic success. One hundred fifteen patients with CSA were studied. Sixty-six patients (57.4%) underwent a SNS, and 49 patients (42.6%) underwent a MMTS. SNS yielded only 8/66 (12.1%) successes on the first night, whereas a MMTS yielded 19/49 (38.8%) successes (p = 0.001, two-tailed Fishers exact). Patients who underwent a SNS eventually had similar rate of success as patients studied with MMTS (60.6 vs 63.3%, NS), but required more testing. Adaptive servo-ventilation was the most successful modality tested, yielding 36/46 (78.3%) successes. Trials of additional modalities following a failed trial of CPAP often produce a successful option that may guide therapy in patients with CSA. This approach may lead to establishing the diagnosis and treatment plans faster, while reducing unnecessary testing.

Sleep in Critically Ill Chemically Paralyzed Patients Requiring Mechanical Ventilation

OBJECTIVE

To determine sleep characteristics in patients receiving mechanical ventilation who require a neuromuscular blocking agent (NMBA).

DESIGN

Observational study.

SETTING

Adult medical ICU at a university hospital.

PARTICIPANTS

Eighteen patients with respiratory failure requiring mechanical ventilation were classified into three groups based on medication regimen determined a priori: intermittent sedation (IS), continuous sedation (CS), or CS and an NMBA.

MEASUREMENTS

Twenty-four-hour polysomnography was performed to determine sleep architecture and fragmentation. Measurement of severity of illness, laboratory indexes, patient-care interventions, and drug dosage were compared between groups, and the effects on sleep staging and fragmentation were analyzed. Sleep stages were scored manually using criteria of Rechtschaffen and Kales, as well as by a modified 50-muV voltage criteria for scoring delta activity.

RESULTS

All patients demonstrated abnormal sleep architecture. In each group of patients, the total sleep time (TST) was > 10 h. There was no statistical difference in the delta activity between the two scoring methods; delta activity was increased in all groups: 32.9%, 49.6%, and 43.7% in the IS, CS, and CS/NMBA groups, respectively. Patients receiving NMBAs spent 22% of the sleep period awake. Rapid eye movement sleep could not be detected in the patients receiving NMBAs and was reduced in the other two groups (3.5%). TST, sleep stage, or arousal/awakening index were not statistically correlated with either severity of illness, clinical laboratory indexes, drug dosage, patient-care interventions, or mode of mechanical ventilation.

CONCLUSION

TST during a 24-h period is not reduced in patients requiring mechanical ventilation. Delta activity is increased and may reflect age, drug, or a contributing metabolic process. The effect of wakefulness in patients receiving chemical paralysis on recovery and weaning from mechanical ventilation, and overall clinical outcome is unknown.

Sleep in acute care units

Patients in the acute care units (ACU) are usually critically ill, making them more susceptible to the unfavorable atmosphere in the hospital. One of these unfavorable factors is sleep disruption and deprivation. Many factors may affect sleep in the ACU, including therapeutic interventions, diagnostic procedures, medications, the underlying disease process, and noise generated in the ACU environment. Many detrimental physiological effects can occur secondary to noise and sleep deprivation, including cardiovascular stimulation, increased gastric secretion, pituitary and adrenal stimulation, suppression of the immune system and wound healing, and possible contribution to delirium. Over the past few years, many studies have endeavored to objectively assess sleep in the ACUs, as well as the effect of mechanical ventilation and circadian rhythm changes critically ill patients. At this time, therefore, it is important to review published data regarding sleep in ACUs, in order to improve the knowledge and recognition of this problem by health care professionals. We have therefore reviewed the methods used to assess sleep in ACUs, factors that may affect sleep in the ACU environment, and the clinical implications of sleep disruption in the ACU.

Sleep-related breathing disorders in obese patients presenting with acute respiratory failure

INTRODUCTION

The study was conducted to assess the clinical and polysomnographic characteristics of patients with sleep-related breathing disorders who presented to the intensive care unit (ICU) with acute respiratory failure and the practicability of performing polysomnography for such patients.

MATERIAL AND METHODS

We analyzed clinical presentation, cause of admission to the ICU, ICU course and outcome of 11 subjects with acute respiratory failure who were diagnosed to have sleep disordered breathing based on polysomnography between October 1999 and January 2003. Subjects were compared to 11 patients with obstructive sleep apnea syndrome matched to each subject using body mass index, age and apnea hypopnea index measured at the time of diagnosis (matched comparison group). Repeated arterial blood gases and polysomnography were done for 8 subjects compliant to treatment 6-8 months after discharge from ICU.

RESULTS

The reason for ICU admission for all subjects was hypercapnic respiratory failure. pH and daytime PaO2 were significantly lower in studied subjects compared to the matched comparison group while awake daytime PaCO2 was significantly higher. Subjects had frequent episodes of hypoventilation. Follow up arterial blood gases and polysomnography 6-8 months after treatment (non-invasive ventilation) in compliant subjects showed significant improvement in all blood gases parameters.

CONCLUSIONS

Early polysomnography (or portable cardio-respiratory monitoring) allows accurate diagnosis and institution of the appropriate ventilation method Further studies should assess the evolution of respiratory drive in patients with sleep disordered breathing and hypercapnia under therapy (non-invasive ventilation).

Sleep-related breathing disorders in patients who are critically ill

This descriptive study describes the frequency and severity of sleep-related breathing disorders in men who are hemodynamically stable who have an acute cardiovascular illness and are hospitalized in a critical care unit. Sixty-four males, aged 55-79 years, with an acute cardiovascular illness, stable hemodynamics, and no ongoing chest pain or history of sleep apnea were studied for 1 night in the critical care unit using polysomnography. Forty-seven percent of the sample had an apnea-hypopnea index > or = 5, with events of both obstructive and central etiologies, including Cheyne-Stokes respiration. Oxygen desaturation to < or = 90% occurred in 61% of the sample. There were no episodes of chest pain, ventricular tachycardia, or heart block associated with apneic or hypopneic events; however, dysrhythmias, including sinus bradycardia, supraventricular tachycardia, and premature ventricular beats, were associated with apneic and hypopneic events.

Sleep-related breathing disorders in acute respiratory failure assisted by non-invasive ventilatory treatment: utility of portable polysomnographic system

In the majority of patients admitted to an Intensive Care Unit with acute respiratory failure (ARF), the aetiology for ARF is quite evident. In a minority of patients no obvious aetiology is apparent at presentation. In this group a previously unrecognized sleep-related breathing disorder (SRBD) may be the cause of the ARF. In spite of clinical suspicion SRBD remains infrequently diagnosed in ARF also because the technology necessary for this type of diagnosis (polysomnography) is usually unavailable in Intensive Care Units. The aim of this study was to evaluate the utility of portable polysomnography system (PSGp) in a group of patients with ARF of unclear aetiology and with a clinical suspicion of SRBD. We studied a selected group of 14 patients (eight males, six females) admitted to an Intermediate Intensive care unit with varying degree of acute respiratory failure. Mean (SD) age was 57 (13) years, pH 7.28 (0.04), PaO2 5.6 (0.7) kPa), PaO2 (8.8 (1.6) kPa), Body mass index 42.7 (9.6) kg m(-2). The patients had no history of skeletal, neuromuscular or cardiovascular disease. None of them had a history of overt chronic lung diseases or had obvious respiratory tract infections. They were submitted to cardiac and respiratory functional evaluation and to nightly PSGp (VITALOG HMS 5000, Respironics Inc., Redwood City, CA, U.S.A.) which was performed in an intermediate intensive care unit. Ten subjects had obstructive sleep apnoea-hypopnoea syndrome (OSAS), with mean respiratory disorder index h(-1) (RDI) 60.1 (25.9) [in five associated with obesity-hypoventilation syndrome (OHS)]; two had central sleep apnoea with mean RDI 45 (28.3) (one with hypothyroidism and one with cerebral multiple infarctions and right hemidiaphragmatic paralysis) and two had OHS with mean RDI 12.5 (3.5). Nocturnal hypoventilation was present in almost all patients. Continuous positive airway pressure (CPAP) was effective in three patients. Eight patients needed to be treated with BILEVEL (BiPAP, Respironics Inc.) airway positive pressure in timed or spontaneous/timed modes. Two patients required intubation and mechanical ventilatory treatment. In one patient with hypothyroidism was sufficient to institute hormonal therapy. Our study shows that acute respiratory failure due to SRBD is not exceptional in an Intermediate Intensive Care Unit and that if clinical suspicion is strong, portable polysomnography may yield diagnostic confirmation and help in establishing appropriate treatment and in avoiding the invasive ventilatory treatment.

Patient perception of sleep quality and etiology of sleep disruption in the intensive care unit

The etiology of sleep disruption in patients in intensive care units (ICUs) is poorly understood, but is thought to be related to environmental stimuli, especially noise. We sampled 203 patients (121 males and 82 females) from different ICUs (cardiac [CCU], cardiac stepdown [CICU], medical [MICU], and surgical [SICU]) by questionnaire on the day of their discharge from the unit, to determine the perceived effect of environmental stimuli on sleep disturbances in the ICU. Perceived ICU sleep quality was significantly poorer than baseline sleep at home (p = 0.0001). Perceived sleep quality and daytime sleepiness did not change over the course of the patients' stays in the ICU, nor were there any significant differences (p > 0.05) in these parameters among respective units. Disruption from human interventions and diagnostic testing were perceived to be as disruptive to sleep as was environmental noise. In general, patients in the MICU appeared to be more susceptible to sleep disruptions from environmental factors than patients in the other ICUs. Our data show that: (1) poor sleep quality and daytime sleepiness are problems common to all types of ICUs, and affect a broad spectrum of patients; and (2) the environmental etiologies of sleep disruption in the ICU are multifactorial.

Sleep in the intensive care unit

The most critically ill patients in the hospital are located in the ICU. Due to intensive individualized care and monitoring, these patients often suffer from severe sleep deprivation. The amount and continuity of sleep as well as normal sleep architecture are all affected. Moreover, by impairing protein synthesis, cell division, and cellular immunity, sleep deprivation can affect the healing process and thus contribute to an increased morbidity and mortality. Reasons for sleep deprivation appear to be multifactorial and include the following: the patient's chronic underlying illness, an acute superimposed illness or surgical procedure, medications used in treatment of the primary illness, and the ICU environment itself. Therapeutic interventions need to address each of these potential causes, with an emphasis placed on providing an environment that is both diurnal and focused on the importance of uninterrupted sleep.