Quantity and quality of sleep in the surgical intensive care unit: are our patients sleeping?

Sleep and critical care

PURPOSE OF REVIEW

Sleep distortion has been studied as an independent risk factor for morbidity and mortality; however, this role in the ICU patients is unclear. These patients suffer from psychological and physiological stressors and significant disturbance in sleep. We conducted a systematic review of all recent data over the last decade to elaborate the extent and implications of sleep disruption in the ICU.

RECENT FINDINGS

Despite adequate data proving that ICU patients have poor quality of sleep over the last three decades, the implications of the sleep distortion in this patient population remains misunderstood. Recently, the Whitehall cohort trial has raised interest in sleep and mortality and substantial data have surfaced regarding prevalence of sleep disturbance in the ICU.

SUMMARY

This article discusses the available data on sleep disruption in patients in the ICU and implications with discussion of effects of ventilators and commonly used medications in the ICU. We will conclude with interventions to improve sleep in the intensive care setting.

An evaluation of the neuroendocrine response to sleep in pediatric burn patients

INTRODUCTION

Previous work demonstrated reduced stage 3+4 and rapid eye movement (REM) sleep following burn injury. This study evaluated the hormonal effects of drug intervention on measures of endocrine status. A secondary objective examined the relationship between hormones and sleep stage distribution.

METHODS

Forty patients 3-18 years of age with a mean percent total body surface area burn of 50.1 +/- 2.9 were randomly assigned to zolpidem or haloperidol utilizing a blinded crossover design. Polysomnography was performed 6 nights, 3/week over 2 weeks. Each week's first night of monitoring was conducted without medication, serving as a baseline. Hormonal levels (epinephrine, norepinephrine, growth hormone, melatonin, dehydroepiandrosterone [DHEA], serotonin, cortisol) were obtained at 0600 h each study day.

RESULTS

Both drugs were associated with increased DHEA levels (P < .03); no other hormones were affected by medication. Significant inverse correlation was observed between REM sleep and epinephrine (r = -.34, P = .004) and norepinephrine levels (r = -.45, P = .02). A positive relationship existed between serotonin and sleep stage 3+4 (r = 0.24, P = .01) and REM (r = 0.48, P = .01). No other significant associations were identified between hormones and sleep.

CONCLUSIONS

This work characterizes the relationship between sleep deprivation and select endocrine parameters postburn. Drug interventions utilized in this study were either ineffective or insufficient in modulating improved hormonal response. Significance of zolpidem's and haloperidol's effect on serum levels of DHEA is unclear. The inverse correlation of epinephrine with REM may suggest that hypermetabolism associated with burns is partly due to lack of REM sleep. Questions remain regarding the effects of sleep deprivation on metabolism and clinical outcome.

Sleep and delirium in ICU patients: a review of mechanisms and manifestations

Sleep deprivation and delirium are conditions commonly encountered in intensive care unit patients. Sleep in these patients is characterized by sleep fragmentation, an increase in light sleep, and a decrease of both slow wave sleep and rapid eye movement sleep. The most common types of delirium in this population are hypoactive and mixed-type. Knowledge about the mechanisms of sleep and delirium has evolved over time, but these phenomena are not yet well understood. What is known, however, is that different areas in the brainstem transmit information to the thalamus and cortex necessary for sleep-wake regulation. Delirium is related to an imbalance in the synthesis, release, and inactivation of some neurotransmitters, particularly acetylcholine and dopamine. The relationship between sleep deprivation and delirium has been studied for many years and has been viewed as reciprocal. The link between them may be ascribed to shared mechanisms. An imbalance in neurotransmitters as well as alteration of melatonin production may contribute to the pathogenesis of both phenomena. A better understanding of the mechanisms and factors that contribute to sleep deprivation and delirium can guide the development of new methods and models for prevention and treatment of these problems and consequently improve patient outcomes.

Psychiatric aspects of heart and lung disease in critical care

Psychiatric issues are important in the management of patients with heart and lung disease in acute, intensive, and critical care. Adjustment disorders, anxiety disorders, depression, and delirium, sometimes in association with substance abuse and withdrawal problems, are the most common issues, and may affect risk and prognosis of the associated general medical conditions and management in the acute care setting. In children with lung and heart diseases requiring critical care, appreciation of cognitive and social-psychologic developmental milestones is necessary to provide adequate care.

Sleep in hospitalized medical patients, part 1: factors affecting sleep

BACKGROUND

Multiple factors lead to sleep disturbances in hospitalized medical patients. Inadequate sleep can lead to both psychological and physiological consequences.

METHODS

A PubMed search was conducted using the terms: ("sleep deprivation," "sleep," or "insomnia") and ("hospitalized," "inpatient," "critical illness," or "acute illness") to review the published data on the topic of sleep in hospitalized medical patients. The search was limited to English-language articles published between 1997 and 2008. Subsequent PubMed searches were performed to clarify the data described in the initial search, including the terms "hospital noise," "hospital environment," "obstructive sleep apnea," and "heart failure."

RESULTS

Few articles specifically addressed the topic of sleep in hospitalized medical patients. Data were limited to observational studies that included outcomes such as sleep complaints and staff logs of wakefulness and sleep. In Part 1, we review normal sleep architecture, and discuss how major medical disorders, the hospital environment, and medications can disrupt sleep during hospitalization. In Part 2, we will propose an evaluation and treatment algorithm to optimize sleep in hospitalized medical patients.

CONCLUSIONS

Hospitalization may severely disrupt sleep, which can worsen pain, cardiorespiratory status, and the psychiatric health of acutely ill patients. Like vital signs, the patient sleep quality reveals much about patients' overall well-being, and should be a routine part of medical evaluation.

The perioperative management of pain from intracranial surgery

Analgesic therapy following intracranial procedures remains a source of concern and controversy. Although opioids are the mainstay of the "balanced" general anesthetic techniques frequently used during intracranial procedures, neurosurgeons and others have been reluctant to administer opioid analgesics to patients following such procedures. This practice is supported by the concern that the sedation and miosis associated with opioid administration could mask the early signs of intracranial catastrophe, or even exacerbate it through decreased ventilatory drive, elevated arterial carbon dioxide levels, and increased cerebral blood flow. This reluctance to use opioids following intracranial surgery is enabled by decades of training and anecdote emphasizing that pain is minimal following these procedures. However, recent data suggests otherwise, and raises the question of how to provide safe and effective analgesia for these patients. Here, this data is reviewed along with the relevant pain pathways, analgesic drugs and techniques, and the available data on their use following intracranial surgery. Although pain following intracranial surgery appears to be more intense than initially believed, it is readily treated safely and effectively with techniques that have proven useful following other types of surgery, including patient-controlled administration of opioids. The use of multimodal analgesic therapy is emphasized not only for its effectiveness, but to reduce dosages and, therefore, side effects, primarily of the opioids, that could be of legitimate concern to physicians and affect the comfort of their patients.

Sleep and recovery from critical illness and injury: a review of theory, current practice, and future directions

OBJECTIVE

The objectives of this article were to describe the deleterious effects of sleep deprivation, characterize sleep in patients cared for in an intensive care unit (ICU) environment, and propose an integrated strategy to improve sleep in critical care units.

STUDY SELECTION

Clinical trials and review articles assessing sleep deprivation, sleep in a critical care setting, and interventions to improve sleep in the critical care environment were identified through an in depth PubMed search.

CONCLUSIONS

Sleep deprivation and disruption are particularly prevalent in patients cared for in the critical care environment. Although numerous observational studies during the past several decades have demonstrated that sleep in patients cared for in ICUs is highly abnormal, little is known about the effects of poor sleep quality on outcomes from critical illness or injury. Reasons for sleep deprivation during recovery from illness and injury in the ICU are multifactorial. Major contributing factors in this patient population are type and severity of underlying illness, the pathophysiology of acute illness/injury, pain from surgical procedures, and perhaps most importantly, the ICU environment itself. Sleep in ICU patients is characterized by prolonged sleep latencies, sleep fragmentation, decreased sleep efficiency, frequent arousals, a predominance of stage 1 and 2 nonrapid eye movement sleep, decreased or absent stage 3 and 4 nonrapid eye movement sleep, and decreased or absent rapid eye movement sleep. Optimizing patient comfort and ensuring that patients achieve adequate restorative sleep while cared for in the ICU is an arduous task. However, environmental alterations in the ICU may reliably improve sleep quality and subsequently alter outcomes during recovery from critical illness and injury.

Good night, sleep tight: the time is ripe for critical care providers to wake up and focus on sleep

The role of sleep during recovery from acute illness has been overlooked for decades. Advances in the support of critically ill patients have been made in mechanical ventilation, specialized nutrition support, highly specific antibiotic therapy, and early rehabilitation. However, the promotion of sleep – a basic tenet for survival – has been actively ignored by critical care providers. Bourne and coworkers recently conducted a small clinical trial that describes improved sleep efficiency with oral melatonin use in critically ill patients.