Delirium. Advances in diagnosis, pathophysiology, and treatment

Cytokines and inflammatory biomarkers and their association with post-operative delirium: a meta-analysis and systematic review

Delirium is a prevalent cognitive disorder among older patients and a common phenomenon following major surgical procedures. This study aimed to identify the significant proteomic biomarkers and examine their association with postoperative delirium (POD). Four electronic databases were used to identify the published articles between 1st January 2000 and 31st December 2023. Among the included 40 studies, the meta-analysis investigated 13 potential cytokines and inflammatory biomarker proteins linked with postoperative delirium. The Hedge's g standardized mean difference (SMD) was applied to calculate the effect size, with 95% confidence intervals (CIs), under the fixed effect or random effect model based on the heterogeneity index of I2. Patients with POD exhibited significantly higher elevated levels of inflammatory biomarkers IL-6 (SMD = 1.45), CRP (SMD = 1.26), GFAP (SMD = 1.15), IL-1B (SMD = 0.95), IL-10 (SMD = 0.57), IL-8 (SMD = 0.56), MCP-1 (SMD = 0.39), and NFL (SMD = 0.44), suggesting that these proteins may play an inevitable role in delirium-associated cytokines and inflammatory response, development and progression of delirium. Conversely, a reduction in IGF-1 protein level (SMD =  - 0.24) was also significantly associated with POD, suggesting a potential vulnerability to delirium. This study paves the way for future research aimed at early diagnosis, personalized treatment, and the development of novel therapeutic strategies to manage delirium effectively.

Delirium care in hospitals in Ireland on World Delirium Awareness Day 2023

BACKGROUND

Acute, transient, but sometimes persistent, delirium is characterized by a sharp disruption in attention, consciousness, and cognitive function, and can be caused by many medications and disorders. Delirium occurrence and negative consequences, such as falls and functional decline, can be decreased with multifactorial prevention and timely detection.

AIMS

To describe current clinical practice in relation to the prevention, assessment, and management of delirium in Irish hospitals; awareness-raising and educational activities; and barriers to good practice.

METHODS

On World Delirium Awareness Day (15th March 2023), a global survey was conducted of delirium prevalence and care. A senior clinical staff member on each participating ward reported on delirium prevalence at 8AM and 8PM, and on usual ward practice; this data was entered into an online survey by a data collector (typically a clinician from the site, visiting several wards to record data). This study reports data from Irish hospitals.

RESULTS

In total, 132 wards from 15 hospitals across Ireland participated. Almost 60% of wards used 'personal judgment' for delirium assessment. Having at least one delirium training session in the preceding year was associated with greater use of a formal assessment tool (60.3% versus 18.8%; p < 0.001). Wards reported staff training/education as the main priority to improve care, but 72.7% of wards identified insufficient time to train staff as a key barrier.

CONCLUSIONS

Clinical practice related to delirium care requires improvement. Awareness raising and staff training require more focus and time in busy clinical settings.

Tapentadol Versus Oxycodone for Opioid-Related Adverse Drug Events and Clinical Outcomes After Inpatient Surgery

Oxycodone is a commonly prescribed opioid for postoperative pain. However, there has been a marked increase in the use of tapentadol over the previous decade due to a perceived superior safety profile of tapentadol compared to oxycodone. There is limited real-world evidence on the safety of tapentadol compared to oxycodone after surgery. The primary objective was to examine the impact of tapentadol compared to oxycodone use on the incidence of opioid-related adverse drug events after surgery. Data for adult surgical patients receiving tapentadol or oxycodone during hospitalization between January 1, 2018, and December 31, 2021, were collected from electronic medical records of 3 tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events. Patients receiving tapentadol or oxycodone were matched using nearest-neighbour propensity score matching. In the matched cohorts (n = 1,530 vs n = 2,775; mean [standard deviation] age 62.3 [17.0] years vs 61.9 [standard deviation 17.9] years; 43% vs 45% male for the tapentadol vs oxycodone groups, respectively), patients given tapentadol experienced a similar incidence of adverse events overall (14.4%, 220/1,530 vs 12.6%, 349/2,775; P = .100; 95% CI -.35% to 3.95%). Secondary outcomes included an increased risk of delirium (2.7%, 41/1,530 vs 1.3%, 37/2,775), arrhythmias (3.4%, 52/1,530 vs 2.2%, 62/2,775), and length of hospital stay (5 [range 1-201] vs 4 [range 1-226] days) compared with oxycodone use. Further real-world studies are warranted to determine the impact of tapentadol use on a broad range of patient outcomes. PERSPECTIVE: This study provides an early signal that tapentadol use may be associated with an increased risk of some adverse events and a longer length of stay. Further research is needed to examine the impact of tapentadol use on a broad range of patient outcomes in clinical practice settings.

2022 Society of Critical Care Medicine Clinical Practice Guidelines on Prevention and Management of Pain, Agitation, Neuromuscular Blockade, and Delirium in Critically Ill Pediatric Patients With Consideration of the ICU Environment and Early Mobility

RATIONALE

A guideline that both evaluates current practice and provides recommendations to address sedation, pain, and delirium management with regard for neuromuscular blockade and withdrawal is not currently available.

OBJECTIVE

To develop comprehensive clinical practice guidelines for critically ill infants and children, with specific attention to seven domains of care including pain, sedation/agitation, iatrogenic withdrawal, neuromuscular blockade, delirium, PICU environment, and early mobility.

DESIGN

The Society of Critical Care Medicine Pediatric Pain, Agitation, Neuromuscular Blockade, and Delirium in critically ill pediatric patients with consideration of the PICU Environment and Early Mobility Guideline Taskforce was comprised of 29 national experts who collaborated from 2009 to 2021 via teleconference and/or e-mail at least monthly for planning, literature review, and guideline development, revision, and approval. The full taskforce gathered annually in-person during the Society of Critical Care Medicine Congress for progress reports and further strategizing with the final face-to-face meeting occurring in February 2020. Throughout this process, the Society of Critical Care Medicine standard operating procedures Manual for Guidelines development was adhered to.

METHODS

Taskforce content experts separated into subgroups addressing pain/analgesia, sedation, tolerance/iatrogenic withdrawal, neuromuscular blockade, delirium, PICU environment (family presence and sleep hygiene), and early mobility. Subgroups created descriptive and actionable Population, Intervention, Comparison, and Outcome questions. An experienced medical information specialist developed search strategies to identify relevant literature between January 1990 and January 2020. Subgroups reviewed literature, determined quality of evidence, and formulated recommendations classified as "strong" with "we recommend" or "conditional" with "we suggest." Good practice statements were used when indirect evidence supported benefit with no or minimal risk. Evidence gaps were noted. Initial recommendations were reviewed by each subgroup and revised as deemed necessary prior to being disseminated for voting by the full taskforce. Individuals who had an overt or potential conflict of interest abstained from relevant votes. Expert opinion alone was not used in substitution for a lack of evidence.

RESULTS

The Pediatric Pain, Agitation, Neuromuscular Blockade, and Delirium in critically ill pediatric patients with consideration of the PICU Environment and Early Mobility taskforce issued 44 recommendations (14 strong and 30 conditional) and five good practice statements.

CONCLUSIONS

The current guidelines represent a comprehensive list of practical clinical recommendations for the assessment, prevention, and management of key aspects for the comprehensive critical care of infants and children. Main areas of focus included 1) need for the routine monitoring of pain, agitation, withdrawal, and delirium using validated tools, 2) enhanced use of protocolized sedation and analgesia, and 3) recognition of the importance of nonpharmacologic interventions for enhancing patient comfort and comprehensive care provision.

Double standard: why electrocardiogram is standard care while electroencephalogram is not?

PURPOSE OF REVIEW

Major adverse cardiovascular and cerebrovascular events (MACCE) significantly affect the surgical outcomes. Electrocardiogram (ECG) has been a standard intraoperative monitor for 30 years. Electroencephalogram (EEG) can provide valuable information about the anesthetized state and guide anesthesia management during surgery. Whether EEG should be a standard intraoperative monitor is discussed in this review.

RECENT FINDINGS

Deep anesthesia has been associated with postoperative delirium, especially in elderly patients. Intraoperative EEG monitoring has been demonstrated to reduce total anesthesia drug use during general anesthesia and postoperative delirium.

SUMMARY

Unlike ECG monitoring, the EEG under general anesthesia has not been designated as a standard monitor by anesthesiologist societies around the world. The processed EEG technology has been commercially available for more than 25 years and EEG technology has significantly facilitated its intraoperative use. It is time to consider EEG as a standard anesthesia monitor during surgery.

Sleep and Delirium in Older Adults

Purpose of Review

Poor sleep and delirium are common in older patients but recognition and management are challenging, particularly in the intensive care unit (ICU) setting. The purpose of this review is to highlight current research on these conditions, their inter-relationship, modes of measurement, and current approaches to management.

Recent Findings

Sleep deprivation and delirium are closely linked, with shared clinical characteristics, risk factors, and neurochemical abnormalities. Acetylcholine and dopamine are important neurochemicals in the regulation of sleep and wakefulness and their dysregulation has been implicated in development of delirium. In the hospital setting, poor sleep and delirium are associated with adverse outcomes; non-pharmacological interventions are recommended, but tend to be resource intensive and hindered by a lack of reliable sleep measurement tools. Delirium is easier to identify, with validated tools available in both ICU and non-ICU settings; however, an optimal treatment approach remains unclear. Antipsychotics are used widely to prevent and treat delirium, although the efficacy data are equivocal. Bundled non-pharmacologic approaches represent a promising framework for prevention and management.

Summary

Poor sleep and delirium are common problems in older patients. While these phenomena appear linked, a causal relationship is not clearly established. At present, there are no established sleep-focused guidelines for preventing or treating delirium. Novel interventions are needed that address poor sleep and delirium, particularly in older adults.

Processed Electroencephalogram Monitoring and Postoperative Delirium: A Systematic Review and Meta-analysis

WHAT WE ALREADY KNOW ABOUT THIS TOPIC

WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: Postoperative delirium complicates approximately 15 to 20% of major operations in patients at least 65 yr old and is associated with adverse outcomes and increased resource utilization. Furthermore, patients with postoperative delirium might also be at risk of developing long-term postoperative cognitive dysfunction. One potentially modifiable variable is use of intraoperative processed electroencephalogram to guide anesthesia. This systematic review and meta-analysis examines the relationship between processed electroencephalogram monitoring and postoperative delirium and cognitive dysfunction.

METHODS

A systematic search for randomized controlled trials was conducted using Ovid MEDLINE, PubMed, EMBASE, Cochrane Library, and Google search using the keywords processed electroencephalogram, Bispectral Index, postoperative delirium, postoperative cognitive dysfunction. Screening and data extraction were conducted by two independent reviewers, and risk of bias was assessed. Postoperative delirium combined-effect estimates calculated with a fixed-effects model were expressed as odds ratios with 95% CIs.

RESULTS

Thirteen of 369 search results met inclusion criteria. Postoperative cognitive dysfunction data were excluded in meta-analysis because of heterogeneity of outcome measurements; results were discussed descriptively. Five studies were included in the quantitative postoperative delirium analysis, with data pooled from 2,654 patients. The risk of bias was low in three studies and unclear for the other two. The use of processed electroencephalogram-guided anesthesia was associated with a 38% reduction in odds for developing postoperative delirium (odds ratio = 0.62; P < 0.001; 95% CI, 0.51 to 0.76).

CONCLUSIONS

Processed electroencephalogram-guided anesthesia was associated with a decrease in postoperative delirium. The mechanism explaining this association, however, is yet to be determined. The data are insufficient to assess the relationship between processed electroencephalogram monitoring and postoperative cognitive dysfunction.

Cholinesterase inhibitors for the treatment of delirium in non-ICU settings

BACKGROUND

Delirium is a common clinical syndrome defined as alterations in attention with an additional disturbance in cognition or perception, which develop over a short period of time and tend to fluctuate during the course of the episode. Delirium is commonly treated in hospitals or community settings and is often associated with multiple adverse outcomes such as increased cost, morbidity, and even mortality. The first-line intervention involves a multicomponent non-pharmacological approach that includes ensuring effective communication and reorientation in addition to providing reassurance or a suitable care environment. There are currently no drugs approved specifically for the treatment of delirium. Clinically, however, various medications are employed to provide symptomatic relief, such as antipsychotic medications and cholinesterase inhibitors, among others.

OBJECTIVES

To evaluate the effectiveness and safety of cholinesterase inhibitors for treating people with established delirium in a non-intensive care unit (ICU) setting.

SEARCH METHODS

We searched ALOIS, which is the Cochrane Dementia and Cognitive Improvement Group's Specialised Register, on 26 October 2017. We also cross-checked the reference lists of included studies to identify any potentially eligible trials.

SELECTION CRITERIA

We included randomised controlled trials, published or unpublished, reported in English or Chinese, which compared cholinesterase inhibitors to placebo or other drugs intended to treat people with established delirium in a non-ICU setting.

DATA COLLECTION AND ANALYSIS

We used the standard methodological procedures expected by Cochrane. The primary outcomes were duration of delirium, severity of delirium, and adverse events. The secondary outcomes were use of rescue medications, persistent cognitive impairment, length of hospitalisation, institutionalisation, mortality, cost of intervention, leaving the study early, and quality of life. For dichotomous outcomes, we calculated the risk ratio (RR) with 95% confidence intervals (CIs); for continuous outcomes we calculated the mean difference (MD) with 95% CIs. We assessed the quality of evidence using GRADE to generate a 'Summary of findings' table.

MAIN RESULTS

We included one study involving 15 participants from the UK. The included participants were diagnosed with delirium based on the Confusion Assessment Method (CAM) criteria. Eight males and seven females were included, with a mean age of 82.5 years. Seven of the 15 participants had comorbid dementia at baseline. The risk of bias was low in all domains.The study compared rivastigmine with placebo. We did not find any clear differences between the two groups in terms of duration of delirium (MD -3.6, 95% CI -15.6 to 8.4), adverse events (nausea, RR 0.30, 95% CI 0.01 to 6.29), use of rescue medications (RR 0.13, 95% CI 0.01 to 2.1), mortality (RR 0.10, 95% CI 0.01 to 1.56), and leaving the study early (RR 0.88, 95% CI 0.07 to 11.54). Evidence was not available regarding the severity of delirium, persistent cognitive impairment, length of hospitalisation, cost of intervention, or other predefined secondary outcomes.The quality of evidence is low due to the very small sample size.

AUTHORS' CONCLUSIONS

There is insufficient evidence to support or refute the use of cholinesterase inhibitors for the treatment of delirium in non-ICU settings. No clear benefits or harms associated with cholinesterase inhibitors were observed when compared with placebo due to the lack of data. More trials are required.

Mechanisms involved in brain dysfunction in mechanically ventilated critically ill patients: implications and therapeutics

Critical illness may lead to significant long-term neurological morbidity and patients frequently develop neuropsychological disturbances including acute delirium or memory impairment after intensive care unit (ICU) discharge. Mechanical ventilation (MV) is a risk factor to the development of adverse neurocognitive outcomes. Patients undergoing MV for long periods present neurologic impairment with memory and cognitive alteration. Delirium is considered an acute form of brain dysfunction and its prevalence rises in mechanically ventilated patients. Delirium duration is an independent predictor of mortality, ventilation time, ICU length of stay and short- and long-term cognitive impairment in the ICU survivors. Although, neurocognitive sequelae tend to improve after hospital discharge, residual deficits persist even 6 years after ICU stay. ICU-related neurocognitive impairments occurred in many cognitive domains and are particularly pronounced with regard to memory, executive functions, attentional functions, and processing speed. These sequelae have an important impact on patients' lives and ICU survivors often require institutionalization and hospitalization. Experimental studies have served to explore the possible mechanisms or pathways involved in this lung to brain interaction. This communication can be mediated via a complex web of signaling events involving neural, inflammatory, immunologic and neuroendocrine pathways. MV can affect respiratory networks and the application of protective ventilation strategies is mandatory in order to prevent adverse effects. Therefore, strategies focused to minimize lung stretch may improve outcomes, avoiding failure of distal organ, including the brain. Long-term neurocognitive impairments experienced by critically ill survivors may be mitigated by early interventions, combining cognitive and physical therapies. Inpatient rehabilitation interventions in ICU promise to improve outcomes in critically ill patients. The cross-talk between lung and brain, involving specific pathways during critical illness deserves further efforts to evaluate, prevent and improve cognitive alterations after ICU admission, and highlights the crucial importance of tailoring MV to prevent adverse outcomes.

"I Can Remember Sort of Vivid People…but to Me They Were Plasticine." Delusions on the Intensive Care Unit: What Do Patients Think Is Going On?

INTRODUCTION

Patients who develop intensive care unit (ICU) acquired delirium stay longer in the ICU, and hospital, and are at risk of long-term mental and physical health problems. Despite guidelines for patient assessment, risk limitation, and treatment in the ICU population, delirium and associated delusions remain a relatively common occurrence on the ICU. There is considerable information in the literature describing the incidence, suspected causes of, and discussion of the benefits and side-effects of the various treatments for delirium in the ICU. But peer-reviewed patient-focused research is almost non-existent. There is therefore a very limited understanding of the reality of delusions in the intensive care unit from the patient's point of view.

METHOD

A secondary analysis of the original interviews conducted by the University of Oxford Health Experiences Research Group was undertaken to explore themes relating specifically to sleep and delirium.

RESULTS

Patients describe a liminal existence on the ICU. On the threshold of consciousness their reality is uncertain and their sense of self is exposed. Lack of autonomy in an unfamiliar environment prompts patients to develop explanations and understandings for themselves with no foothold in fact.

CONCLUSION

Patients on the ICU are perhaps more disoriented than they appear and early psychological intervention in the form of repeated orientation whilst in the ICU might improve the patient experience and defend against development of side-effects.

Interventions for preventing delirium in hospitalised non-ICU patients

BACKGROUND

Delirium is a common mental disorder, which is distressing and has serious adverse outcomes in hospitalised patients. Prevention of delirium is desirable from the perspective of patients and carers, and healthcare providers. It is currently unclear, however, whether interventions for preventing delirium are effective.

OBJECTIVES

To assess the effectiveness of interventions for preventing delirium in hospitalised non-Intensive Care Unit (ICU) patients.

SEARCH METHODS

We searched ALOIS - the Cochrane Dementia and Cognitive Improvement Group's Specialized Register on 4 December 2015 for all randomised studies on preventing delirium. We also searched MEDLINE (Ovid SP), EMBASE (Ovid SP), PsycINFO (Ovid SP), Central (The Cochrane Library), CINAHL (EBSCOhost), LILACS (BIREME), Web of Science core collection (ISI Web of Science), ClinicalTrials.gov and the WHO meta register of trials, ICTRP.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of single and multi- component non-pharmacological and pharmacological interventions for preventing delirium in hospitalised non-ICU patients.

DATA COLLECTION AND ANALYSIS

Two review authors examined titles and abstracts of citations identified by the search for eligibility and extracted data independently, with any disagreements settled by consensus. The primary outcome was incidence of delirium; secondary outcomes included duration and severity of delirium, institutional care at discharge, quality of life and healthcare costs. We used risk ratios (RRs) as measures of treatment effect for dichotomous outcomes; and between group mean differences and standard deviations for continuous outcomes.

MAIN RESULTS

We included 39 trials that recruited 16,082 participants, assessing 22 different interventions or comparisons. Fourteen trials were placebo-controlled, 15 evaluated a delirium prevention intervention against usual care, and 10 compared two different interventions. Thirty-two studies were conducted in patients undergoing surgery, the majority in orthopaedic settings. Seven studies were conducted in general medical or geriatric medicine settings.We found multi-component interventions reduced the incidence of delirium compared to usual care (RR 0.69, 95% CI 0.59 to 0.81; seven studies; 1950 participants; moderate-quality evidence). Effect sizes were similar in medical (RR 0.63, 95% CI 0.43 to 0.92; four studies; 1365 participants) and surgical settings (RR 0.71, 95% CI 0.59 to 0.85; three studies; 585 participants). In the subgroup of patients with pre-existing dementia, the effect of multi-component interventions remains uncertain (RR 0.90, 95% CI 0.59 to 1.36; one study, 50 participants; low-quality evidence).There is no clear evidence that cholinesterase inhibitors are effective in preventing delirium compared to placebo (RR 0.68, 95% CI, 0.17 to 2.62; two studies, 113 participants; very low-quality evidence).Three trials provide no clear evidence of an effect of antipsychotic medications as a group on the incidence of delirium (RR 0.73, 95% CI, 0.33 to 1.59; 916 participants; very low-quality evidence). In a pre-planned subgroup analysis there was no evidence for effectiveness of a typical antipsychotic (haloperidol) (RR 1.05, 95% CI 0.69 to 1.60; two studies; 516 participants, low-quality evidence). However, delirium incidence was lower (RR 0.36, 95% CI 0.24 to 0.52; one study; 400 participants, moderate-quality evidence) for patients treated with an atypical antipsychotic (olanzapine) compared to placebo (moderate-quality evidence).There is no clear evidence that melatonin or melatonin agonists reduce delirium incidence compared to placebo (RR 0.41, 95% CI 0.09 to 1.89; three studies, 529 participants; low-quality evidence).There is moderate-quality evidence that Bispectral Index (BIS)-guided anaesthesia reduces the incidence of delirium compared to BIS-blinded anaesthesia or clinical judgement (RR 0.71, 95% CI 0.60 to 0.85; two studies; 2057 participants).It is not possible to generate robust evidence statements for a range of additional pharmacological and anaesthetic interventions due to small numbers of trials, of variable methodological quality.

AUTHORS' CONCLUSIONS

There is strong evidence supporting multi-component interventions to prevent delirium in hospitalised patients. There is no clear evidence that cholinesterase inhibitors, antipsychotic medication or melatonin reduce the incidence of delirium. Using the Bispectral Index to monitor and control depth of anaesthesia reduces the incidence of postoperative delirium. The role of drugs and other anaesthetic techniques to prevent delirium remains uncertain.

[Delirium: an interdisciplinary challenge]

Delirium, the acute deterioration of cognitive function and attention, is the most frequent mental disorder in elderly. Its correct diagnosis and adequate management are of crucial importance for the patient's health and functional outcome. First of all, one has to be aware of the possibilities of preventing this complex, potentially life-threatening problem, which means recognizing the patient at risk, avoiding environmental stress and causal factors (i.e., anticholinergic medication) in cognitively impaired patients, and timely reaction to prodromal symptoms. Causal therapy (i.e., treatment of the causal condition and/or eliminating the precipitating situation) is imperative. It must be accompanied by nursing and environmental measures and, if necessary, by antipsychotic and/or sedating symptomatic treatment.

Optimizing perioperative care for patients with hip fracture

Hip fracture is one of the most common orthopedic conditions associated with significant morbidity and mortality. Patients with hip fracture are usually older, with significant comorbidities. Delayed surgical treatment beyond 48 hours after admission is associated with significantly higher mortality. Hereby clinicians are presented with the challenge to optimize the complex hip fracture within a short time period. This article reviews the evidence regarding preoperative, intraoperative, and postoperative considerations, and provides insights into the best strategies with which to optimize the patient's condition and improve perioperative outcomes.

Sleep disorders and acute nocturnal delirium in the elderly: a comorbidity not to be overlooked

Delirium is a disturbance of consciousness and cognition that results in a confusional state. It tends to fluctuate in intensity and is often observed in older patients. Sleep is a window of vulnerability for the occurrence of delirium and sleep disorders can play a role in its appearance. In particular, delirious episodes have been associated with obstructive sleep apnoea syndrome, which is reported to be frequent in the elderly. Hereby, we present a case-report documenting the sudden onset of a confusional state triggered by obstructive sleep apnoea-induced arousal, together with a review of the literature on the topic. We emphasise that, among the many pathogenic factors implicated in delirium, it is worth considering the possible link between nocturnal delirium and the occurrence of impaired arousals. Indeed, the complex confusional manifestations of delirium could be due, in part, to persistence of dysfunctional sleep activity resulting in an inability to sustain full arousal during behavioural wakefulness. Arousals can be triggered by sleep disturbances or other medical conditions. Clinicians should be aware that older patients may present disordered sleep patterns, and make investigation of sleep patterns and disorders potentially affecting sleep continuity a key part of their clinical workup, especially in the presence of cognitive comorbidities. Correct diagnosis and optimal treatment of sleep disorders and disrupted sleep can have a significant impact in the elderly, improving sleep quality and reducing the occurrence of abnormal sleep-related behaviours.

Pediatric delirium: monitoring and management in the pediatric intensive care unit

This review article updates the pediatric medical community on the current literature regarding diagnosis and treatment of delirium in critically ill children. This information will be of value to pediatricians, intensivists, and anesthesiologists in developing delirium monitoring and management protocols in their pediatric critical care units.

Role of Dexmedetomidine for the Prevention and Treatment of Delirium in Intensive Care Unit Patients

OBJECTIVE:

To review recent clinical studies regarding the role of dexmedetomidine for prevention and treatment of delirium in intensive care unit (ICU) patients.

DATA SOURCES:

MEDLINE and PubMed searches (1988-Feburary 2013) were conducted, using the key words delirium, dexmedetomidine, Precedex, agitation, α-2 agonists, critical care, and intensive care. References from relevant articles were reviewed for additional information.

STUDY SELECTION AND DATA EXTRACTION:

Clinical trials comparing dexmedetomidine with other sedatives/analgesics or with antipsychotics for delirium were selected. Studies that evaluated the use of dexmedetomidine for sedation for more than 6 hours were included in this review.

DATA SYNTHESIS:

Dexmedetomidine is a highly selective α-2 receptor agonist that provides sedation, anxiolysis, and modest analgesia with minimal respiratory depression. Its mechanism of action is unique compared with that of traditional sedatives because it does not act on γ-aminobutyric acid receptors. In addition, dexmedetomidine lacks anticholinergic activity and promotes a natural sleep pattern. These pharmacologic characteristics may explain the possible antidelirium effects of dexmedetomidine. Eight clinical trials, including 5 double-blind randomized trials, were reviewed to evaluate the impact of dexmedetomidine on ICU delirium.

CONCLUSIONS:

Currently available evidence suggests that dexmedetomidine is a promising agent, not only for prevention but also for treatment of ICU-associated delirium. However, larger, well-designed trials are warranted to define the role of dexmedetomidine in preventing and treating delirium in the ICU.

The impact of intra- and postoperative albumin levels as a biomarker of delirium after cardiopulmonary bypass: results of an exploratory study

In this prospective study the frequency of delirium after cardiac surgery with cardiopulmonary bypass (CPB) was determined. Furthermore, we investigated the impact of intra- and postoperative levels of albumin as a biomarker of delirium. Thirty-four patients who underwent elective CPB at the Department of Cardiac Surgery, Ludwig-Maximilians-University of Munich, Germany, were enroled in this prospective study. During the intensive care unit (ICU) stay and shortly after discharge from the ICU, delirious state was evaluated daily using the Delirium-Rating-Scale. Albumin was assayed pre-anaesthesia, immediately after induction of anaesthesia, at the beginning of the heart-lung-apparatus period, immediately before the opening and 5min after the opening of the aortic clamp, 24h and 48h postoperatively and on the day before discharge. After CPB, a clinical significant delirious state was observed in 11 patients (32.4%). The albumin level decreased during the surgical intervention and increased postoperatively with a maximum level at the time of discharge. CPB patients with delirious state showed a significantly lower albumin level 24h and 48h postoperatively than those without delirium. A low level of postoperative albumin seems to be a useful biomarker to identify patients with high risk of delirious state after CPB.

Evaluation of patients with delirium in the emergency department

OBJECTIVE

Delirium is a neuropsychiatric syndrome characterized by acute onset and a fluctuating course of globally altered mental status. It has been reported that the frequency of delirium among patients hospitalized with any disorder ranges from 2 to 30%. However, in the literature, few studies have evaluated the frequency of delirium in hospitalized patients, including those older than 65 years. According to our knowledge, this is the first study on adult patients in all age groups in an emergency department. We aimed to classify delirium according to its etiological causes and to compare the age groups for frequency and these causes.

MATERIAL AND METHODS

Forty-three patients were included in the study; they had been diagnosed with delirium according to the Diagnostic and Statistical Manual of Mental Disorders (DSM)-IV in an emergency department from December 2002 to December 2003. The patients were divided into two groups (group I: age <65 years, group II: age ≥65 years). Following a detailed history, each patient underwent a physical and neurological examination. Additionally, the Mini-Mental State Examination was administered. Radiological and hematological examinations were conducted on all patients who had indications for such testing.

RESULTS

Of the patients with delirium, 18 were female and 25 were male. Mean age was 61.18 years (range 18 to 90 years). Of the 43 patients, 21 were in group I and 22 were in group II. The most common causes of delirium were metabolic disorders. There was no significant difference between group I and II for the frequency or etiological causes of delirium.

CONCLUSION

In emergency departments, all patients with delirium should be evaluated for etiological factors, especially metabolic disorders, as treatment of the underlying cause is essential in delirium.

Derivation and validation of a clinical prediction rule for delirium in patients admitted to a medical ward: an observational study

OBJECTIVES

To develop and validate a simple clinical prediction rule, based on variables easily measurable at admission, to identify patients at high risk of developing delirium during their hospital stay on an internal medicine ward.

DESIGN

Prospective study of two cohorts of patients admitted between 1 May and 30 June 2008 (derivation cohort), and between 1 May and 30 June 2009 (validation cohort).

SETTING

A tertiary hospital in Donostia-Gipuzkoa (Spain).

PARTICIPANTS

In total 397 patients participated in the study. The mean age and incidence of delirium were 75.9 years and 13%, respectively, in the derivation cohort, and 75.8 years and 25% in the validation cohort.

MAIN OUTCOME MEASURES

The predictive variables analysed and finally included in the rule were: being aged 85 years old or older, being dependent in five or more activities of daily living, and taking two or more psychotropic drugs (antipsychotics, benzodiazepines, antidepressants, anticonvulsant and/or antidementia drugs). The variable of interest was delirium as defined by the short Confusion Assessment Method, which assesses four characteristics: acute onset and fluctuating course, inattention, disorganised thinking and altered level of consciousness.

RESULTS

We developed a rule in which the individual risk of delirium is obtained by adding one point for each criterion met (age≥85, high level of dependence, and being on psychotropic medication). The result is considered positive if the score is ≥1. The rule accuracy was: sensitivity=93.4% (95% CI 85.5% to 97.2%), specificity=60.6% (95% CI 54.1% to 66.8%), positive predictive value=44.4% (95% CI 36.9% to 52.1%) and negative predictive value=96.5% (95% CI: 92% to 98.5%). The area under the receiver operator characteristic (ROC) curve was 0.85 for the validation cohort.

CONCLUSIONS

The presence or absence of any of the three predictive factors (age≥85, high level of dependence and psychotropic medication) allowed us to classify patients on internal medicine wards according to the risk of developing delirium. The simplicity of the variables in our clinical prediction rule means that the data collection required is feasible in busy medicine units.

Delirium: an emerging frontier in the management of critically ill children

Delirium is a syndrome of acute brain dysfunction that commonly occurs in critically ill adults and most certainly is prevalent in critically ill children all over the world. The dearth of information about the incidence, prevalence, and severity of pediatric delirium stems from the simple fact that there have not been well-validated instruments for routine delirium diagnosis at the bedside. This article reviewed the emerging solutions to this problem, including description of a new pediatric tool called the pCAM-ICU. In adults, delirium is responsible for significant increases in both morbidity and mortality in critically ill patients. The advent of new tools for use in critically ill children will allow the epidemiology of this form of acute brain dysfunction to be studied adequately, will allow clinical management algorithms to be developed and implemented following testing, and will present the necessary incorporation of delirium as an outcome measure for future clinical trials in pediatric critical care medicine.

Association between contact precautions and delirium at a tertiary care center

OBJECTIVE

To investigate the relationship between contact precautions and delirium among inpatients, adjusting for other factors.

DESIGN

Retrospective cohort study.

SETTING

A 662-bed tertiary care center.

PATIENTS

All nonpyschiatric adult patients admitted to a tertiary care center from 2007 through 2009.

METHODS

Generalized estimating equations were used to estimate the association between contact precautions and delirium in a retrospective cohort of 2 years of admissions to a tertiary care center.

RESULTS

During the 2-year period, 60,151 admissions occurred in 45,266 unique nonpsychiatric patients. After adjusting for comorbid conditions, age, sex, intensive care unit status, and length of hospitalization, contact precautions were significantly associated with delirium (as defined by International Classification of Diseases, Ninth Revision), medication, or restraint exposure (adjusted odds ratio [OR], 1.40 [95% confidence interval {CI}, 1.24-1.51]). The association between contact precautions and delirium was seen only in patients who were newly placed under contact precautions during the course of their stay (adjusted OR, 1.75 [95% CI, 1.60-1.92]; P < .01) and was not seen in patients who were already under contact precautions at admission (adjusted OR, 0.97 [95% CI, 0.86-1.09]; P = .06).

CONCLUSIONS

Although delirium was more common in patients who were newly placed under contact precautions during the course of their hospital admission, delirium was not associated with contact precautions started at hospital admission. Patients newly placed under contact precautions after admission but during hospitalization appear to be at a higher risk and may benefit from proven delirium-prevention strategies.

Diagnosing delirium in elderly Thai patients: utilization of the CAM algorithm

Background

Delirium is a common illness among elderly hospitalized patients. However, under-recognition of the condition by non-psychiatrically trained personnel is prevalent. This study investigated the performance of family physicians when detecting delirum in elderly hospitalized Thai patients using the Thai version of the Confusion Assessment Method (CAM) algorithm.

Methods

A Thai version of the CAM algorithm was developed, and three experienced Thai family physicians were trained in its use. The diagnosis of delirium was also carried out by four fully qualified psychiatrists using DSM-IV TR criteria, which can be considered the gold standard. Sixty-six elderly patients were assessed with MMSE Thai 2002, in order to evaluate whether they had dementia upon admission. Within three days of admission, each patient was interviewed separately by a psychiatrist using DSM-IV TR, and a family physician using the Thai version of the CAM algorithm, with both sets of interviewers diagnosing for delirium.

Results

The CAM algorithm tool, as used by family physicians, demonstrated a sensitivity of 91.9% and a specificity of 100.0%, with a PPV of 100.0% and an NPV of 90.6%. Interrater agreement between the family physicians and the psychiatrists was good (Cohen's Kappa = 0.91, p < 0.0001). The mean of the time the family physicians spent using CAM algorithm was significantly briefer than that of the psychiatrists using DSM-IV TR.

Conclusions

Family physicians performed well when diagnosing delirium in elderly hospitalized Thai patients using the Thai version of the CAM algorithm, showing that this measurement tool is suitable for use by non-psychiatrically trained personnel, being short, quick, and easy to administer. However, proper training on use of the algorithm is required.

Symptoms of delirium: an exploratory factor analytic study among referred patients

OBJECTIVE

Factor analytic studies of delirium symptoms among patients referred through consultation-liaison psychiatric services are rare. We examined the factor structure of delirium symptoms in referred patients and determined whether combining items from several delirium rating scales influenced the factor structure of delirium symptoms.

METHOD

Eighty-six patients with delirium (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision) referred though the consultation-liaison services were assessed with structured rating scales. Nineteen symptom items extracted from the Delirium Rating Scale-Revised-98 (DRS-R-98), the Memorial Delirium Assessment Scale and the Confusional State Evaluation Scale were subjected to an exploratory (principal component) factor analysis. A second such analysis was conducted on 15 items of the DRS-R-98 for comparison.

RESULTS

Compared with prior studies, patients were younger and the majority had hyperactive delirium. Principal components analysis identified two factors: (1) a "cognitive" factor comprising of disturbances in language, thought processes, orientation, attention, short- and long-term memory, visuospatial ability, consciousness (awareness) and perseveration accounted for 28.9% of the variance and (2) a "behavioral" factor consisting of sleep-wake cycle disturbances, delusions, perceptual disturbances, motor agitation, affect-lability, distractibility, irritability and temporal onset accounted for 18.9% of the variance. An identical factor structure was obtained with the DRS-R-98 items.

CONCLUSIONS

Similar to previous factor analytic studies, the present study supported the existence of two principal dimensions of delirium, cognitive and behavioral. Additionally, it extended the results of earlier investigations to a wider group of patients with delirium, suggesting that these dimensions might provide important clues to the neurobiology of delirium.

A factor analytic study of the Delirium Rating Scale-Revised-98 in untreated patients with delirium

OBJECTIVE

Existing factor analytic studies of symptoms of delirium are mostly based on small numbers of patients from specialized settings. This study thus sought to examine the factor structure of symptoms of delirium in a reasonably large sample of untreated patients referred to liaison psychiatric services of a multi-specialty hospital in north India, employing the more commonly used Delirium Rating Scale-Revised Version-1998 (DRS-R-98).

METHOD

Patients (n=151) who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for delirium were assessed with the DRS-R-98 prior to starting treatment with psychotropics. A principal component analysis was carried out to determine the factor structure of the symptoms based on these ratings.

RESULTS

Unlike previous efforts, patients of this study were relatively younger (mean age 47 years), with mainly hyperactive delirium, and did not have comorbid dementia. Three factors which together explained 47.32 % of variance of symptoms were identified. A "global cognitive" factor including disturbances of orientation, attention, short- and long-term memory, and visuospatial ability accounted for 18.33% of the variance. A "sleep and motor symptoms" factor consisting of sleep-wake cycle disturbances; delusions; and perceptual disturbances including hallucinations, motor-agitation, inverse of motor-retardation, and affect-lability accounted for 16% of the variance. A "thought and language" factor comprising abnormalities in language and thought process, temporal onset, and fluctuation of symptoms explained 13% of the variance.

CONCLUSIONS

Thus, the current factor analysis not only confirmed the presence of three principal symptom dimensions of delirium (found in several previous studies) but also extended these findings to a broader group of patients usually referred to liaison psychiatric services.

Ease of screening for depression and delirium in patients enrolled in inpatient hospice care

BACKGROUND

Major depression and delirium are prevalent, underrecognized, and undertreated in hospice and palliative care settings. Furthermore, they are both associated with significant morbidity and mortality.

OBJECTIVE

A screening study of patients receiving inpatient hospice care was conducted in order to determine the ease of screening for depression and delirium in patients with advanced, life-threatening illnesses by hospice social workers and nurses, respectively.

METHODS

A two-question depression screening tool was administered to 20 consecutive patients on admission to a hospice general inpatient care center by social work staff during their initial assessment. A delirium-screening tool was administered daily to 22 consecutive patients admitted to the ICC daily by nursing staff. Screening results were collected, as were patient and staff feelings about the burden of the screening process.

RESULTS

Of the 20 patients screened on admission for depression by social work, 70% (14/20) screened positive. Of the 22 patients screened daily for delirium by nursing, 64% (14/22) screened positive at least once during their admission. Screening for both conditions was considered relatively easy to accomplish by the hospice staff. There were no significant associations between a positive screen of depression or delirium and patient gender, age, ethnicity, terminal diagnosis, or marital status.

DISCUSSION

These results support the notion that depression and delirium are very common in hospice inpatients, and that screening for both is relatively easy and practical for hospice clinicians to conduct.

Providing perioperative care for patients with hip fractures

Providing perioperative care for patients with hip fractures can present major challenges for the anaesthesiologist. These patients often have multiple comorbidities, the deterioration of any one of which may have precipitated the fall. A careful balance has to be achieved between minimising the time before operation and spending time to optimise their medical status. This review will present insights into preoperative patient assessment and optimization in this group of patients from the anaesthesiologists' perspective. In particular, it will highlight important medical issues of concern that may alter anaesthetic risks and management. With a greater understanding of what these issues are, potentially a more prompt and integrated approach to managing these patients may be made. Hopefully, this would result in minimising last minute cancellations due to medical reasons for these patients.

Delirium in children and adolescents

OBJECTIVE

To study the clinical profile of children and adolescents (< or = 14 years) referred to the Consultation-Liaison (CL) psychiatry services of a Tertiary Care Centre.

DESIGN

Retrospective chart review.

SETTING

Patients seen by the CL psychiatry services of Department of Psychiatry, Postgraduate Institute of Medical Education and Research, Chandigarh.

PARTICIPANTS

Subjects diagnosed as delirium (as per ICD-10) during their inpatient stay was done.

MAIN OUTCOME MEASURES

phenomenology of delirium and response to treatment.

RESULT

Forty-six children and adolescents were diagnosed as delirium by the psychiatry consultation-liaison team. The most common underlying pathology was infection of various types, followed by neoplasms. All subjects exhibited sleep-wake cycle disturbance and impaired orientation. Other common symptoms were impaired attention (89.5%), impaired short-term memory (84.2%), agitation (68.4%), and lability of affect (60.5%). Delusions and hallucinations were reported by only a few patients. Most of the patients were treated with low dose haloperidol and they responded well.

CONCLUSION

Sleep wake cycle disturbances and cognitive dysfunction are common in children and adolescents with delirium.

Delirium: an emerging frontier in the management of critically ill children

The objectives of this article are (1) to introduce pediatric delirium and provide understanding of acute brain dysfunction with its classification and clinical presentations (2) to understand how delirium is diagnosed and discuss current modes of delirium diagnosis in the critically ill adult population and translation to pediatrics (3) to understand the prevalence and prognostic significance of delirium in the adult and pediatric critically ill population (4) to discuss the pathophysiology of delirium as currently understood, and (5) to provide general management guidelines for delirium.

Delirium in the intensive care unit

Delirium is a common manifestation of acute brain dysfunction in critically ill patients with prevalence as high as 75%. In the last years there has been a progressive increase of publications regarding intensive care (ICU) delirium, acknowledging its importance. The occurrence of delirium in ICU is related to more adverse outcomes including self-extubation and removal of catheters, prolonged hospitalization, increased costs, higher mortality, and potentially, long-term cognitive impairment. The pathophysiology explaining the processes subtending the development of delirium is still elusive, though several theories have been discussed. It is known that different risk factors are associated with delirium in the ICU. Patients in ICU frequently receive medications to treat pain and to ensure sedation, but an association between these drugs and delirium has been shown. Therefore, this pharmacological exposure should be modified to reduce the risk factors. Giving the multifactorial genesis of delirium, multicomponent interventions to prevent delirium developed in non-ICU settings can be adapted to critically ill patients with the purpose of reducing the incidence. When delirium is diagnosed the use of typical and atypical antipsychotics may be effective for its treatment. Future studies should evaluate target interventions to prevent delirium in the ICU.

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 issues in palliative care: Recognition of delirium in patients enrolled in hospice care

Objectives:

Delirium is prevalent, difficult to assess, under-recognized, and undertreated in hospice and palliative care settings. Furthermore, it is associated with significant morbidity and mortality. Under-recognition of delirium results in under-treatment and increased suffering. The intent of this study was to retrospectively evaluate the recognition of delirium in a large cohort of hospice patients by interdisciplinary hospice care teams.

Methods:

A retrospective chart review of 2,716 patients receiving hospice care was conducted in order to determine the baseline rate of recognition of delirium in patients with advanced, life-threatening illnesses by front-line hospice clinicians. Documentation of “delirium” as either a diagnosis or problem was used as an estimate of how often these disorders were considered significant issues by the treating interdisciplinary team.

Results:

Of the patients receiving home/long-term care, 17.8% (386/2168) had delirium documented as a diagnosis or significant problem. The presence of recognized delirium in this setting was associated with significant differences in marital status, ethnicity, hospice diagnosis, and age. Total length of hospice care was also significantly longer. Of patients receiving inpatient care, 28.3% (614/548) had delirium documented as a diagnosis or significant problem. Recognized delirium in this setting was associated with significant differences in gender, ethnicity, hospice diagnosis, and length of inpatient stay.

Significance of results:

If documentation is representative of the care that the interdisciplinary teams provide, delirium of any kind appears to be under-recognized in this population. In fact, it is on the low end of prevalence estimates in the literature. Improved delirium assessment is needed in order to minimize the impact of delirium on patients living with advanced, life-threatening illnesses and their caregivers.

Delirium in the intensive care unit

Delirium, an acute and fluctuating disturbance of consciousness and cognition, is a common manifestation of acute brain dysfunction in critically ill patients, occurring in up to 80% of the sickest intensive care unit (ICU) populations. Critically ill patients are subject to numerous risk factors for delirium. Some of these, such as exposure to sedative and analgesic medications, may be modified to reduce risk. Although dysfunction of other organ systems continues to receive more clinical attention, delirium is now recognized to be a significant contributor to morbidity and mortality in the ICU, and it is recommended that all ICU patients be monitored using a validated delirium assessment instrument. Patients with delirium have longer hospital stays and lower 6-month survival than do patients without delirium, and preliminary research suggests that delirium may be associated with cognitive impairment that persists months to years after discharge. Little evidence exists regarding the prevention and treatment of delirium in the ICU, but multicomponent interventions reduce the incidence of delirium in non-ICU studies. Strategies for the prevention and treatment of ICU delirium are the subjects of multiple ongoing investigations.

Delirium in the Intensive Care Unit: A Narrative Review of Published Assessment Tools and the Relationship between ICU Delirium and Clinical Outcomes

Delirium is defined as an acute change or fluctuation in mental status, plus inattention, and either disorganised thinking or altered level of consciousness at the time of evaluation. Increasing numbers of studies confirm that delirium is very common in intensive care unit patients. This review summarises current knowledge about ICU delirium and offers some avenues for future research. This is a summary of Dr Waters' dissertation for the DICM.

Individual delirium symptoms: do they matter?

OBJECTIVES

To evaluate the impact of individual manifestations of delirium on outcome, describe them in critically ill adults, and validate nurses' bedside item assessments from the Intensive Care Delirium Screening Checklist (ICDSC).

DESIGN

Prospective study.

SETTING

Single 16-bed medical/surgical university hospital intensive care unit.

PATIENTS

Six hundred consecutive patients admitted to the intensive care unit for >24 hrs.

INTERVENTIONS

All patients were evaluated with the eight-item ICDSC throughout their intensive care unit stay. In all patients scoring positive on any ICDSC item, individual checklist items were tallied throughout the intensive care unit stay and assessed for impact on mortality. In addition, when the ICDSC score indicated delirium (> or = 4 of 8), the subsequent overall frequency of each item was also independently documented to describe delirious patient symptoms. ICDSC items were tested for discrimination between delirious and nondelirious patients. Throughout the study, the validity of bedside delirium assessments was assessed in 30 nurses.

MEASUREMENTS AND MAIN RESULTS

We were able to assess 537 patients. In nondelirious patients, psychomotor agitation by ICDSC assessment was associated with a higher risk of mortality after adjustment for Acute Physiology and Chronic Health Evaluation, age, and the presence of coma. One hundred eight-nine patients (35.1%) developed delirium (i.e., ICDSC score > or = 4). On presentation (and throughout the intensive care unit stay), the most frequent features of delirium were inattention, disorientation, and psychomotor agitation. Each ICDSC item was highly discriminating between delirious vs. nondelirious patients. Correlation between gold standard adjudicators and nurses for the overall bedside evaluations of delirium were excellent (Pearson's correlation R = 0.924, p < .0005). Individual symptom evaluation by nurses varied: Alteration in level of consciousness was poorest (R = 0.681, p < .0005), and both disorientation and hallucinations evaluated best (R = 1.000).

CONCLUSIONS

In nondelirious patients, agitation was associated with a higher risk of mortality. Each of the eight ICDSC items is highly discriminating for the diagnosis of delirium, suggesting that any screening or diagnostic scales should incorporate them. Quality assurance and educational efforts should, therefore, emphasize independent assessment of the individual features of delirium.

Depressive symptoms and the risk of incident delirium in older hospitalized adults

OBJECTIVES

To determine whether specific subsets of symptoms from the Geriatric Depression Scale (GDS), assessed at hospital admission, were associated with the incidence of delirium.

DESIGN

Secondary analysis of a prospective cohort study of patients from the Delirium Prevention Trial.

SETTING

General medicine service at Yale New Haven Hospital, March 25, 1995, through March 18, 1998.

PARTICIPANTS

Four hundred sixteen patients aged 70 and older who were at intermediate or high risk for delirium and were not taking antidepressants at hospital admission.

MEASUREMENTS

Depressive symptoms were assessed GDS, and daily assessments of delirium were obtained using the Confusion Assessment Method.

RESULTS

Of the 416 patients in the analysis sample, 36 (8.6%) developed delirium within the first 5 days of hospitalization. Patients who developed delirium reported 5.7 depressive symptoms on average, whereas patients without delirium reported an average of 4.2 symptoms. Using a Cox proportional hazards model, it was found that depressive symptoms assessing dysphoric mood and hopelessness were predictive of incident delirium, controlling for measures of physical and mental health. In contrast, symptoms of withdrawal, apathy, and vigor were not significantly associated with delirium.

CONCLUSION

These findings suggest that assessing symptoms of dysphoric mood and hopelessness could help identify patients at risk for incident delirium. Future studies should evaluate whether nonpharmacological treatment for these symptoms reduces the risk of delirium.

Interventions for preventing delirium in hospitalised patients

BACKGROUND

Delirium is a common mental disorder with serious adverse outcomes in hospitalised patients. It is associated with increases in mortality, physical morbidity, length of hospital stay, institutionalisation and costs to healthcare providers. A range of risk factors has been implicated in its aetiology, including aspects of the routine care and environment in hospitals. Prevention of delirium is clearly desirable from patients' and carers' perspectives, and to reduce hospital costs. Yet it is currently unclear whether interventions for prevention of delirium are effective, whether they can be successfully delivered in all environments, and whether different interventions are necessary for different groups of patients.

OBJECTIVES

Our primary objective was to determine the effectiveness of interventions designed to prevent delirium in hospitalised patients. We also aimed to highlight the quality and quantity of research evidence to prevent delirium in these settings.

SEARCH STRATEGY

We searched the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 28th September, 2005. As the searches in MEDLINE, EMBASE, CINAHL and PsycINFO for the Specialized Register would not necessarily have picked up all delirium prevention trials, these databases were searched again on 28th October, 2005. We also examined reference lists of retrieved articles, reviews and books. Experts in this field were contacted and the Internet searched for further references and to locate unpublished trials.

SELECTION CRITERIA

Randomised controlled trials evaluating any interventions to prevent delirium in hospitalised patients.

DATA COLLECTION AND ANALYSIS

Data collection and quality assessment were performed by three reviewers independently and agreement reached by consensus.

MAIN RESULTS

Six studies with a total of 833 participants were identified for inclusion. All were conducted in surgical settings, five in orthopaedic surgery and one in patients undergoing resection for gastric or colon cancer. Only one study of 126 hip fracture patients comparing proactive geriatric consultation with usual care was sufficiently powered to detect a difference in the primary outcome, incident delirium. Total cumulative delirium incidence during admission was reduced in the intervention group (OR 0.48 [95% CI 0.23, 0.98]; RR 0.64 [95% CI 0.37, 0.98]), suggesting a 'number needed to treat' of 5.6 patients to prevent one case. The intervention was particularly effective in preventing severe delirium. In logistic regression analyses adjusting for pre fracture dementia and Activities of Daily Living impairment, there was no reduction in effect size, OR 0.6, but this no longer remained significant [95% CI 0.3,1.3]. There was no effect on the duration of delirium episodes, length of hospital stay, and cognitive status or institutionalisation at discharge. There was also no significant difference in cumulative delirium incidence between treatment and control groups in a sub-group of 50 patients with dementia (RR 0.9 [95% CI 0.59, 1.36]). In another trial of low dose haloperidol prophylaxis, there was no difference in delirium incidence but the severity and duration of a delirium episode, and length of hospital stay were all reduced. We identified no completed studies in hospitalised medical, care of the elderly, general surgery, cancer or intensive care patients. In outcomes, no studies examined for death, use of psychotropic medication, activities of daily living, psychological morbidity, quality of life, carers or staff psychological morbidity, cost of intervention and cost to health care services. Outcomes were only reported up to discharge, with no studies reporting medium or longer-term effects.

AUTHORS' CONCLUSIONS

Research evidence on effectiveness of interventions to prevent delirium is sparse. Based on a single study, a programme of proactive geriatric consultation may reduce delirium incidence and severity in patients undergoing surgery for hip fracture. Prophylactic low dose haloperidol may reduce severity and duration of delirium episodes and shorten length of hospital admission in hip surgery. Further studies of delirium prevention are needed.

Coma, delirium, and cognitive dysfunction in critical illness

Syndromes of global cerebral dysfunction that are associated with critical illness include acute disorders (eg, coma, delirium) and chronic processes (ie, cognitive impairment). These syndromes can result from direct cerebral injury; however, many cases develop as a complication of a systemic insult. Coma frequently evolves into phenomenologically distinct disorders of consciousness; it must be differentiated from conditions in which consciousness is preserved, as in the locked-in state. Advances have been made in defining, scoring, and delineating the epidemiology of cerebral dysfunction in the ICU, but research is needed to elucidate underlying mechanisms, with the goal of identifying targets for prevention and therapy.

Delirium in Older Adults With Cancer: Implications for Practice and Research

PURPOSE/OBJECTIVES

To provide a comprehensive review of the literature and existing evidence-based findings on delirium in older adults with cancer.

DATA SOURCES

Published articles, guidelines, and textbooks.

DATA SYNTHESIS

Although delirium generally is recognized as a common geriatric syndrome, a paucity of empirical evidence exists to guide early recognition and treatment of this sequelae of cancer and its treatment in older adults. Delirium probably is more prevalent than citations note because the phenomenon is under-recognized in clinical practice across varied settings of cancer care.

CONCLUSIONS

Extensive research is needed to formulate clinical guidelines to manage delirium. A focus on delirium in acute care and at the end of life precludes identification of this symptom in ambulatory care, where most cancer therapies are used. Particular emphasis should address the early recognition of prodromal signs of delirium to reduce symptom severity.

IMPLICATIONS FOR NURSING

Ongoing assessment opportunities and close proximity to patients' treatment experiences foster oncology nurses' mastery of this common exemplar of altered cognition in older adults with cancer. Increasing awareness of and knowledge delineating characteristics of delirium in older patients with cancer can promote early recognition, optimum treatment, and minimization of untoward consequences associated with the historically ignored example of symptom distress.

Preoperative predictors of delirium after cardiac surgery: a preliminary study

Preoperative risk factors of postoperative delirium were evaluated in 260 patients admitted for open heart surgery. The incidence of delirium was 11.5%. Independent predictors included cognitive impairment, atrial fibrillation, a history of peripheral vascular disease major depression and advanced age. Aforementioned factors might be helpful in predicting delirium following cardiac surgery.

Biperiden-induced delirium model in rats: a behavioral and electroencephalographic study

AIMS AND METHODS

In order to elucidate the neural mechanisms of delirium, we administered the anticholinergic drug, biperiden (40 mg/kg i.p.), to 10 adult male Wistar rats and examined the resulting polygraphic recordings, including electroencephalography (EEG), electrooculography (EOG), and electromyography (EMG), for 60 min following injection. EEG data were investigated quantitatively by power spectrum analyses using fast Fourier transformation. Ten male Wistar rats receiving saline (i.p.) were used as the control group.

RESULTS

Treated rats demonstrated two types of alternating behavioral change: a hyperactive and hypoactive state. In the hyperactive state, rapid walking, excessive random sniffing, and retropulsion were observed, with EEG desynchronization (significantly increased alpha1 (8.0-10.0 Hz), alpha2 (10.0-13.0 Hz), and beta (13.0-30.0 Hz) power values), as well as EEG slowing (significantly increased delta (0.5-4.0 Hz) and theta1 (4.0-6.0 Hz) power values): significantly marked rapid eye movement, and increased EMG activity. In the hypoactive state, motor arrest and drowsiness were observed, with prominent EEG slowing (significantly increased delta and theta1 power values): significantly decreased rapid eye movement and moderately decreased EMG activity. On the other hand, the control group did not show any behavioral or polygraphic changes.

CONCLUSIONS

The behavioral and polygraphic changes induced by biperiden administration in rats are similar to those of delirium in humans. Therefore, it is proposed that biperiden-treated rats are a good delirium model and the anticholinergic mechanism is one of the potent factors in the development of delirium in humans.