Evaluating attention in delirium: A comparison of bedside tests of attention

Acute encephalopathy in the ICU: a practical approach

PURPOSE OF REVIEW

Acute encephalopathy (AE) - which frequently develops in critically ill patients with and without primary brain injury - is defined as an acute process that evolves rapidly and leads to changes in baseline cognitive status, ranging from delirium to coma. The diagnosis, monitoring, and management of AE is challenging. Here, we discuss advances in definitions, diagnostic approaches, therapeutic options, and implications to outcomes of the clinical spectrum of AE in ICU patients without primary brain injury.

RECENT FINDINGS

Understanding and definitions of delirium and coma have evolved. Delirium is a neurocognitive disorder involving impairment of attention and cognition, usually fluctuating, and developing over hours to days. Coma is a state of unresponsiveness, with absence of command following, intelligible speech, or visual pursuit, with no imaging or neurophysiological evidence of cognitive motor dissociation. The CAM-ICU(-7) and the ICDSC are validated, guideline-recommended tools for clinical delirium assessment, with identification of clinical subtypes and stratification of severity. In comatose patients, the roles of continuous EEG monitoring and neuroimaging have grown for the early detection of secondary brain injury and treatment of reversible causes.

SUMMARY

Evidence-based pharmacologic treatments for delirium are limited. Dexmedetomidine is effective for mechanically ventilated patients with delirium, while haloperidol has minimal effect of delirium but may have other benefits. Specific treatments for coma in nonprimary brain injury are still lacking.

Differential Effects of ADHD Polygenic Risk on Cognitive Performance in Later Life

OBJECTIVE

Understanding the association between polygenic risk for ADHD and cognition throughout aging has not been widely studied. This study aimed to determine whether ADHD risk influences cognitive performance among individuals at both young-old and middle-old age.

METHOD

Participants from the Health and Retirement Study, a biennial survey of 20,000 Americans, were compared on executive function and delayed recall measures using regression analyses.

RESULTS

There was no significant effect of ADHD risk on memory at both age waves for African-ancestry (AA; n = 403) and European-ancestry (EA; n = 2,286). There was, however, a significant association between ADHD risk and performance on executive function for EA at middle-old age (p = .028), but not young-old age; no such association was observed for AA adults.

CONCLUSION

This finding suggests that ADHD risk may differentially influence cognition among older adults throughout the aging process, with important implications for future research.

Occurrence of Postoperative Delirium and the Use of Different Assessment Tools

(1) Background: Postoperative delirium (POD) poses a high risk of worsening outcomes for patients and is also a burden for hospitals. The leading guidelines recommend standardized POD assessment and prevention. The aim of this subgroup analysis of the PRe-Operative Prediction of Postoperative DElirium by Appropriate SCreening (PROPDESC) trial was to compare different delirium assessments and to analyse the frequency of POD on five postoperative days. (2) Methods: This prospective observational trial enrolled 1097 patients in a university hospital from 2018 until 2019. The following POD assessment tools were used for five consecutive days: Confusion Assessment Method for ICU (CAM-ICU) or Confusion Assessment Method for normal ward (CAM), 4 A's Test (4AT) and Delirium Observation Screening (DOS) scale. (3) Results: In a 5-day visit interval, most new POD developments occurred on the first and second postoperative day. A clear recommendation for a specific POD assessment tool based on our results cannot be given. (4) Conclusions: According to guidelines, a POD assessment should take place on the first five postoperative days, but of these, the first two are those of highest POD occurrence. The POD assessment tool used should at best include direct patient questioning and aspects of patient observation.

Translational cognitive systems: focus on attention

Cognitive dysfunction, particularly attentional impairment, is a core feature of many psychiatric disorders, yet is inadequately addressed by current treatments. Development of targeted therapeutics for the remediation of attentional deficits requires knowledge of underlying neurocircuit, cellular, and molecular mechanisms that cannot be directly assayed in the clinic. This level of detail can only be acquired by testing animals in cross-species translatable attentional paradigms, in combination with preclinical neuroscience techniques. The 5-choice continuous performance test (5C-CPT) and rodent continuous performance test (rCPT) represent the current state of the art of preclinical assessment of the most commonly studied subtype of attention: sustained attention, or vigilance. These tasks present animals with continuous streams of target stimuli to which they must respond (attention), in addition to non-target stimuli from which they must withhold responses (behavioral inhibition). The 5C-CPT and rCPT utilize the same measures as gold-standard clinical continuous performance tests and predict clinical efficacy of known pro-attentional drugs. They also engage common brain regions across species, although efforts to definitively establish neurophysiological construct validity are ongoing. The validity of these tasks as translational vigilance assessments enables their use in characterizing the neuropathology underlying attentional deficits of animal models of psychiatric disease, and in determining therapeutic potential of drugs ahead of clinical testing. Here, we briefly review the development and validation of such tests of attentional functioning, as well as the data they have generated pertaining to inattention, disinhibition, and impulsivity in psychiatric disorders.

Deconstructing delirium in the post anaesthesia care unit

The course of neuro-cognitive recovery following anaesthesia and surgery is distinctive and poorly understood. Our objective was to identify patterns of neuro-cognitive recovery of the domains routinely assessed for delirium diagnosis in the post anaesthesia care unit (PACU) and to compare them to the cognitive recovery patterns observed in other studies; thereby aiding in the identification of pathological (high risk) patterns of recovery in the PACU. We also compared which of the currently available tests (3D-CAM, CAM-ICU, and NuDESC) is the best to use in PACU. This was a post hoc secondary analysis of data from the Alpha Max study which involved 200 patients aged over 60 years, scheduled for elective surgery under general anaesthesia lasting more than 2 h. These patients were assessed for delirium at 30 min following arrival in the PACU, if they were adequately arousable (Richmond Agitation Sedation Score ≥ −2). All tests for delirium diagnosis (3D-CAM, CAM-ICU, and NuDESC) and the sub-domains assessed were compared to understand temporal recovery of neurocognitive domains. These data were also analysed to determine the best predictor of PACU delirium. We found the incidence of PACU delirium was 35% (3D-CAM). Individual cognitive domains were affected differently. Few individuals had vigilance deficits (6.5%, n = 10 CAM-ICU) or disorganized thinking (19% CAM-ICU, 27.5% 3D-CAM), in contrast attention deficits were common (72%, n = 144) and most of these patients (89.5%, n = 129) were not sedated (RASS ≥ −2). CAM-ICU (27%) and NuDESC (52.8%) detected fewer cases of PACU delirium compared to 3D-CAM. In conclusion, return of neurocognitive function is a stepwise process; Vigilance and Disorganized Thinking are the earliest cognitive functions to return to baseline and lingering deficits in these domains could indicate an abnormal cognitive recovery. Attention deficits are relatively common at 30 min in the PACU even in individuals who appear to be awake. The 3D CAM is a robust test to check for delirium in the PACU.

Effectiveness of a Serious Game Design and Game Mechanic Factors for Attention and Executive Function Improvement in the Elderly: A Pretest-Posttest Study

Attention allows us to focus and process information from our environment, and executive function enables us to plan, work, and manage our daily lives. As individuals become older, both of these cognitive abilities decline. It is essential for the elderly to perform more cognitive exercises. Previous studies have shown that arithmetic calculations require attention span and that playing video games requires executive function. Therefore, we developed a serious game involving mental arithmetic calculations specifically for improving attention span and executive functions. Our objective was to analyze the effectiveness of the game and the efficacy of the game’s mechanic factors affecting attention span and executive function in the elderly. Forty elderly volunteers who are over 60 years of age were invited to join an eight-week cognitive training program through an elderly social welfare center. Four assessment tests were used in pre-test and post-test before and after the training period. D-CAT and SAT are used for screening attention span; TMT-A and TMT-B are used for screening executive function. They were instructed to play the game for at least 15 min per day, 5 days per week, for a total of 8 weeks. There were three independent variables (difficulty, pressure, and competition) with two parameters that could be selected. A paired-sample t-test showed the effective results by comparing the pre-test scores and post-test scores of the cognitive training. There were significant improvements in attention span and executive functions. The mixed repeated-measure ANOVA and MANCOVA results showed that two game mechanic factors (difficulty and pressure) had a significant effect and an interaction effect, but the other factor (competition) had a non-significant effect. In conclusion, the game showed a significant enhancement in both attention span and executive functions after training, and the difficulty factor and the pressure factor were shown to have an effect, but the competition factor was shown to have no effect.

Evaluation of Bedside Tests of Attention and Arousal Assessing Delirium in Parkinson's Disease, Dementia, and Older Adults

BACKGROUND

Delirium is a serious acute neuropsychiatric condition associated with altered attention and arousal.

OBJECTIVE

To evaluate simple bedside tests for attention and arousal to detect delirium in those with and without Parkinson's disease (PD) and dementia.

METHODS

Participants from two prospective delirium studies were pooled comprising 30 with PD without cognitive impairment, 24 with Lewy body cognitive impairment (PD dementia or dementia with Lewy bodies), 16 with another dementia and 179 PD and dementia-free older adults. Participants completed standardised delirium assessments including tests of attention: digit span, Memorial Delirium Assessment Scale (MDAS) attention and months of the year backwards; and arousal: Glasgow Coma Scale (GSC), Observational Scale of Level of Arousal (OSLA), Modified Richmond Agitation Scale and MDAS consciousness. Delirium was diagnosed using the DSM-5 criteria.

RESULTS

On their first admission, 21.7%participants had prevalent delirium. Arousal measures accurately detected delirium in all participants (p < 0.01 for all), but only selected attention measures detected delirium in PD and dementia. In PD and dementia-free older adults, impaired digit span and OSLA were the optimal tests to detect delirium (area under the curve [AUC] = 0.838, p < 0.001) while in PD and dementia the optimal tests were MDAS attention and GCS (AUC=0.90 and 0.84, respectively, p < 0.001 for both).

CONCLUSION

Simple bedside tests of attention and arousal at a single visit could accurately detect delirium in PD, dementia and PD and dementia-free older adults; however, the optimal tests differed between groups. Combined attention and arousal scores increased accuracy, which could have clinical utility to aid the identification of delirium neurodegenerative disorders.

Comparison of verbal and computerised months backwards tests in a hospitalized older population

BACKGROUND

Delirium is extremely prevalent, yet underdiagnosed, in older patients and is associated with prolonged length of hospital stay and higher mortality rates. Impaired attention is the cardinal deficit in delirium and is a required feature in diagnostic criteria. The verbal months backwards test (MBT) is the most sensitive bedside test of attention, however, hospital staff occasionally have difficulty with its administration and interpretation. We hypothesise that the MBT on an electronic tablet may be easier and more consistent to use for both experienced and unexperienced medical professionals and, if the diagnostic efficacy was similar, aid delirium diagnosis.

AIM

We aim to investigate the correlation of the verbal MBT with a computerised MBT application.

METHODS

Participants recruited (age > 65, n = 75) were allocated to different cohorts (Dementia and Delirium (DMDL), Dementia (DM), Delirium (DL), No Neurocognitive Disorder (NNCD)) and were administered both the verbal and electronic versions.

RESULTS

Correlation between measurements were: overall Spearman's rho = 0.772 (p < 0.0001); DMDL rho = 0.666 (p < 0.0001); DL rho = 0.778 (p = 0.039); DM rho = 0.378 (p = 0.203); NNCD rho = 0.143 (p = 0.559).

DISCUSSION

Overall, and for the delirious subset, statistically significant agreement was present. Poor inter-test correlation existed in the groups without delirium (DM, NNCD).

CONCLUSIONS

The MBTc correlates well with the MBTv in patients who are clinically suspected to have delirium but has poor correlation in patients without delirium. Visuospatial cognition and psychomotor deficits in a dementia cohort and mechanical factors (such as tremor, poor fingernail hygiene and visual impairment) in a group with no neurocognitive disorder may limit the utility of the MBTc in a hospitalised older population.

Evaluation and Management of Delirium

Delirium, sometimes referred to as encephalopathy, is an acute confusional state that is both common in hospitalized patients and associated with poor outcomes. For patients, families, and caregivers, delirium can be a traumatic experience. While delirium is one of the most common diagnoses encountered by the consulting neurologist, the majority of the time it will have been previously unrecognized as such by the care team. Neurologic syndromes such as dementia or aphasia can either be misdiagnosed as delirium or may coexist with it, necessitating careful neurologic assessment. Once the diagnosis of delirium has been established, a careful evaluation for predisposing and precipitating factors can help uncover modifiable contributors, which should be addressed as part of a multicomponent, primarily nonpharmacologic intervention. Importantly, delirium management, which begins with comprehensive prevention, should emphasize the humanity of the delirious patient and the challenges of caring for this vulnerable population. When considered, delirium represents an important opportunity for the neurologist to substantially enhance patient care.

[Disorientation and delirium assessment : A secondary analysis of a prospective, observational study]

Disorientation may present as a warning sign of developing delirium. The most commonly used delirium assessment tool in Germany, the Confusion Assessment Method for Intensive Care Unit (CAM-ICU), does not rate "disorientation", since intubated patients cannot communicate verbally. However, the majority of German ICU patients are not orally intubated, so they could be examined for their orientation. This study was carried out to investigate whether the delirium feature "disorientation" in extubated patients yields diverging findings in comparison to the CAM-ICU and whether the sensitivity of the CAM-ICU may be improved when combined with the feature "disorientation" (CAM-IMC). A total of 86 paired assessments were completed in 50 extubated patients. Delirium was found in 19.8% (N = 17). The CAM-ICU had a sensitivity of 71% (95% confidence interval [CI] 44-90%) and a specificity of 100% (95-100%). Disorientation, if taken as the only delirium feature, had a sensitivity of 77% (50-93%) and a specificity of 93% (89-100%). The CAM-IMC reached a sensitivity of 88% (64-99%) and a specificity of 100% (95-100%). The receiver operating characteristics (ROC) analyses found an area under the curve (AUC) of 0.941 (95%CI 0.851-1.000) for the CAM-IMC, which was the highest compared to the other delirium tests (CAM-ICU, AUC 0.853 [0.720-0.986]; disorientation, AUC 0.868 [0.745-0.991]). This research emphasizes the importance of the feature "disorientation" for delirium assessments in patients able to verbally communicate and explains some controversial delirium ratings in daily practice. The CAM-IMC appears to be an attractive tool for delirium assessment in nonintubated patients and deserves further research.

"SQiD, the Single Question in Delirium; can a single question help clinicians to detect delirium in hospitalised cancer patients?" running heading Single Question in Delirium" (Bcan-D-20-01665)

Aim

A serious syndrome for cancer in-patients, delirium risk increases with age and medical acuity. Screening tools exist but detection is frequently delayed or missed. We test the ‘Single Question in Delirium’ (SQiD), in comparison to psychiatrist clinical interview.

Methods

Inpatients in two comprehensive cancer centres were prospectively screened. Clinical staff asked informants to respond to the SQiD: “Do you feel that [patient’s name] has been more confused lately?”. The primary endpoint was negative predictive value (NPV) of the SQiD versus psychiatrist diagnosis (Diagnostic and Statistics Manual criteria). Secondary endpoints included: NPV of the Confusion Assessment Method (CAM), sensitivity, specificity and Cohen’s Kappa coefficient.

Results

Between May 2012 and July 2015, the SQiD plus CAM was applied to 122 patients; 73 had the SQiD and psychiatrist interview. Median age was 65 yrs. (interquartile range 54–74), 46% were female; median length of hospital stay was 12 days (5–18 days). Major cancer types were lung (19%), gastric or other upper GI (15%) and breast (14%). 70% of participants had stage 4 cancer. Diagnostic values were similar between the SQiD (NPV = 74, 95% CI 67–81; kappa = 0.32) and CAM (NPV = 72, 95% CI 67–77, kappa = 0.32), compared with psychiatrist interview. Overall the CAM identified only a small number of delirious cases but all were true positives. The specificity of the SQiD was 87% (74–95) The SQiD had higher sensitivity than CAM (44% [95% CI 41–80] vs 26% [10–48]).

Conclusion

The SQiD, administered by bedside clinical staff, was feasible and its psychometric properties are now better understood. The SQiD can contribute to delirium detection and clinical care for hospitalised cancer patients.

Supplementary information

Supplementary information accompanies this paper at 10.1186/s12885-020-07504-x.

Consciousness and the rabbit holes of delirium

Delirium is a common disorder in hospitalized older adults and the defining characteristic is a disturbance of consciousness. Unfortunately, there are currently no testable measures of consciousness as pertains to its disruption in delirium. Not surprisingly rates of recognition of delirium suffer. Arguably, a greater understanding of the quantum of consciousness may improve delirium diagnosis through better diagnostic tools. Candidate dimensions of consciousness derived from fields of psychology, psychiatry, and philosophy are discussed and relevance to delirium explored. Based upon existing literature in the field of consciousness we identify the pre-reflective state, experiential awareness, and functional networks as candidate sites that may be affected in delirium. Opportunities for clinical instrument development and how these tools can be tested are discussed. We conclude that consciousness content may not hold to a unitary measurement, but facets of its integrity that are impacted in delirium are open to further exploration. Disorders in pre-reflective status, experiential awareness, and functional networks may represent the measurable "rabbit holes" of consciousness disturbance.

Delirium Superimposed on Dementia in Perioperative Period and Intensive Care

Delirium is a life-threatening condition, the causes of which are still not fully understood. It may develop in patients with pre-existing dementia. Delirium superimposed on dementia (DSD) can go completely unnoticed with routine examination. It may happen in the perioperative period and in the critical care setting, especially in the ageing population. Difficulties in diagnosing and lack of specific pharmacological and non-pharmacological treatment make DSD a seriously growing problem. Patient-oriented, multidirectional preventive measures should be applied to reduce the risk of DSD. For this reason, anesthesiologists and intensive care specialists should be aware of this interesting condition in their everyday clinical practice.

Comparison of novel tools with traditional cognitive tests in detecting delirium in elderly medical patients

BACKGROUND

Efficient detection of delirium and comorbid delirium-dementia is a key diagnostic challenge. Development of new, efficient delirium-focused methods of cognitive assessment is a key challenge for improved detection of neurocognitive disorders in everyday clinical practice.

AIM

To compare the accuracy of two novel bedside tests of attention, vigilance and visuospatial function with conventional bedside cognitive tests in identifying delirium in older hospitalized patients.

METHODS

180 consecutive elderly medical inpatients (mean age 79.6 ± 7.2; 51% female) referred to a psychiatry for later life consultation-liaison service with delirium, dementia, comorbid delirium-dementia and cognitively intact controls. Participants were assessed cross-sectionally with conventional bedside cognitive tests [WORLD, Months Backward test (MBT), Spatial span, Vigilance A and B, Clock Drawing test and Interlocking Pentagons test] and two novel cognitive tests [Lighthouse test, Letter and Shape Drawing test (LSD)-4].

RESULTS

Neurocognitive diagnoses were delirium (n = 44), dementia (n = 30), comorbid delirium-dementia (n = 60) and no neurocognitive disorder (n = 46). All conventional tests had sensitivity of > 70% for delirium, with best overall accuracy for the Vigilance-B (78.3%), Vigilance-A (77.8%) and MBT (76.7%) tests. The sustained attention component of the Lighthouse test was the most distinguishing of delirium (sensitivity 84.6%; overall accuracy 75.6%). The LSD-4 had sensitivity of 74.0% and overall accuracy 74.4% for delirium identification. Combining tests allowed for enhanced sensitivity (> 90%) and overall accuracy (≥ 75%) with the highest overall accuracy for the combination of MBT-Vigilance A and the combined Vigilance A and B tests (both 78.3%). When analyses were repeated for those with dementia, there were similar findings with the MBT-Vigilance A the most accurate overall combination (80.0%). Combining the Lighthouse-SA with the LSD-4, a fail in either test had sensitivity for delirium of 91.4 with overall accuracy of 74.4%.

CONCLUSION

Bedside tests of attention, vigilance and visuospatial ability can help to distinguish neurocognitive disorders, including delirium, from other presentations. The Lighthouse test and the LSD-4 are novel tests with high accuracy for detecting delirium.

Delirium in hospitalized older adults

Delirium is a common and underdiagnosed problem in hospitalized older adults. It is associated with an increased risk of poor cognitive and functional outcomes, institutionalization, and death. Timely diagnosis of delirium and non-pharmacological prevention and management strategies can improve patient outcomes. The Confusion Assessment Method (CAM) is the most widely used clinical assessment tool for the diagnosis of delirium. Multiple variations of the CAM have been developed for ease of administration and for the unique needs of specific patient populations, including the 3-min diagnostic CAM (3D CAM), CAM-Intensive Care Unit (CAM-ICU), Delirium Triage Screen (DTS)/Brief CAM (b-CAM), 4AT tool, and ultrabrief delirium assessment. Strong evidence supports the effectiveness of nonpharmacologic strategies as the primary intervention for the prevention of delirium. Multicomponent delirium prevention strategies can reduce the incidence of delirium by 40%. Investigation of underlying medical precipitants and optimization of non-pharmacological interventions are first line in the management of delirium. Despite a lack of evidence supporting use of antipsychotics, low dose antipsychotics remain second line for off-label treatment of distressing psychoses and/or agitated behaviors that are refractory to non-pharmacological behavioral interventions and pose an imminent risk of harm to self or others. Any antipsychotic prescription for delirium should be accompanied by an appropriate taper plan. Follow up with primary care providers on discharge from hospital for ongoing screening of cognitive impairment is important.

Diagnosing delirium in patients with dementia, a great challenge

Delirium, despite its high incidence, serious consequences and potential reversibility, remains an underdiagnosed syndrome. In patients with dementia, the healthcare professional may find significant difficulties in differentiating whether the patient presents cognitive alterations and behavioural disorders characteristic of dementia or, on the contrary, is faced with a delirium superimposed on dementia (DSD). In view of this difficulty, many tools have been proposed in recent years to improve the diagnosis of DSD in these highly complex patients. The aim of these tools is to be easy and quick to apply, and although focusing on assessing cognitive aspects such as attention or level of consciousness, some of them have also incorporated the assessment of other more novel aspects, such as the ability to respond to external stimuli (Arousal) or the degree of mobility.

Selecting a Bedside Cognitive Vital Sign to Monitor Cognition in Hospital: Feasibility, Reliability, and Responsiveness of Logical Memory

Although there is a high prevalence of delirium and cognitive impairment among hospitalised older adults, short, reliable cognitive measures are rarely used to monitor cognition and potentially alert healthcare professionals to early changes that might signal delirium. We evaluated the reliability, responsiveness, and feasibility of logical memory (LM), immediate verbal recall of a short story, compared to brief tests of attention as a bedside “cognitive vital sign” (CVS). Trained nursing staff performed twice-daily cognitive assessments on 84 clinically stable inpatients in two geriatric units over 3–5 consecutive days using LM and short tests of attention and orientation including months of the year backwards. Scores were compared to those of an expert rater. Inter-rater reliability was excellent with correlation coefficients for LM increasing from r = 0.87 on day 1 to r = 0.97 by day 4 (p < 0.0001). A diurnal fluctuation of two points from a total of 30 was deemed acceptable in clinically stable patients. LM scores were statistically similar (p = 0.98) with repeated testing (suggesting no learning effect). All nurses reported that LM was feasible to score routinely. LM is a reliable measure of cognition showing diurnal variation but minimal learning effects. Further study is required to define the properties of an ideal CVS test, though LM may satisfy these.

Distinguishing characteristics of delirium in a skilled nursing facility in Spain: Influence of baseline cognitive status

OBJECTIVE

Mild cognitive impairment (MCI) and dementia (DEM) are prevalent in skilled nursing facilities (SNFs), confounding delirium detection. We report characteristics of delirium in an SNF to ascertain distinguishing features for delirium diagnosis, despite challenges of comorbidity with MCI and DEM.

METHODS

Cross-sectional study of 200 consecutive patients from an SNF in Catalunya, Spain, assessed within the first 24 to 48 admission hours by independent experts with Spanish-Informant Questionnaire on Cognitive Decline in the Elderly (for MCI-DEM), Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) delirium criteria, and Delirium Rating Scale Revised-98 (DRS-R98) for delirium phenomenology. Delirium characteristics were modeled in successive steps, according to the presence of delirium and MCI-DEM, with analysis of variance (ANOVA), receiver operator characteristic analyses, and conditional logistic regression.

RESULTS

The final model produced symptoms that represented each of the three delirium core domains (ie, cognitive, higher order thinking, and circadian). The DRS-R98 items rated these symptoms as moderate-severe attention/vigilance, mild-severe language, and moderate-severe sleep-wake cycle alterations. The delirium discriminant accuracy of the three symptoms together was high: 84.6% in the MCI-DEM group to 92.8% in the No MCI-DEM group.

CONCLUSIONS

Impairments of attention, language, and sleep-wake cycle indicate delirium in SNF patients regardless of the underlying MCI-DEM status. Because delirium is underdetected in SNFs, where nursing staff/patient ratios are low, brief simple tools that measure these symptoms could potentially enhance delirium detection.

Impact of an educational workshop upon psychiatrists' attitudes towards delirium care

OBJECTIVES

Improving knowledge about delirium care is a key target for health care. We describe the implementation of a four-part workshop focusing upon key aspects of delirium care.

METHODS

Attitudes towards and understanding of delirium diagnosis and management amongst psychiatrists were surveyed before and immediately after an educational workshop.

RESULTS

There were 62 participants. Pre-workshop, delirium was rated highly relevant to psychiatry. Overall level of confidence in diagnosis was modest, with the behavioural and psychological symptoms of dementia considered the most challenging differential diagnosis. Only nine participants (15%) correctly identified DSM-5 delirium criteria. Preferred assessment of attention varied with six different approaches endorsed. Confidence was higher for managing hyperactive compared with hypoactive delirium (p&lt;0.001). Pharmacotherapy was more frequently endorsed for hyperactive compared with hypoactive presentations, with haloperidol the most popular agent (p&lt;0.001). A total of 41 (66%) participants completed post-workshop assessments. Post-workshop, there were significant increases to the perceived relevance of delirium (p = 0.003), confidence in overall diagnosis (p&lt;0.001) accuracy of awareness of DSM-5 criteria (p&lt;0.001), and confidence in treating different presentations (p&lt;0.001). The Months Backward Test was the preferred bedside test of attention (38/40 respondents).

CONCLUSIONS

This interactive educational intervention impacted positively upon knowledge and attitudes amongst psychiatrists towards key aspects of delirium care. Further investigation can examine the impact upon longer term knowledge and behaviour.

Delirium in the critically ill patient

Delirium is an acute and transient brain dysfunction that is characterized by disturbances in consciousness, affecting both its content (i.e., attention) and level (i.e., arousal). It affects as many as 50% of those admitted to an intensive care unit (ICU). Once believed to be an inconsequential outcome of critical illness, it is now recognized that delirium is harmful in both the short- and long-term. Despite occurring frequently in critically ill patients, delirium often goes unrecognized. Well-validated delirium screening tools, designed for use in the ICU, should be used to reliably detect delirium. The first step in delirium treatment is to identify and address potentially modifiable risk factors. Multiple trials have shown that benzodiazepines are a risk factor for delirium in a dose-dependent manner. Sedation with nonbenzodiazepine-based strategies are an effective means by which to reduce delirium. Nonpharmacologic strategies such as those which seek to reduce sensory impairment, sleep deprivation, and immobility are effective. Pharmacologic treatment with antipsychotics, though commonly used, is not supported by findings from placebo-controlled trials. Recent data support from multiple trials support the use of the "ABCDEF bundle" as a means by which to reduce delirium.

Performance on bedside tests of attention and organized thinking in patients with dementia free from delirium

ABSTRACTObjectives:Bedside tests of attention and organized thinking were performed in patients with cognitive impairment or dementia but without delirium, to provide estimates of false positive rates for detecting delirium superimposed on dementia (DSD).

DESIGN AND SETTING

This cross-sectional study was conducted in outpatients and institutionalized patients without delirium representing a wide spectrum of severity of cognitive impairments.

PARTICIPANTS

Patients with dementia or a cognitive disorder according to DSM IV criteria, after exclusion of (suspected) delirium according to DSM IV criteria.

MEASUREMENTS

Tests for inattention and disorganized thinking from the CAM-ICU were assessed.

RESULTS

The sample included 163 patients (mean age 83 years (SD 6; 64% women)), with Alzheimer's disease as most prevalent (45%) diagnosis and a mean MMSE-score of 16.8 (SD 7.5). False positive rates of the test of attention varied from 0.04 in patients with normal to borderline cognitive function to 0.8 in those with severe dementia. The false positive rate of the test of disorganized thinking was zero in the normal to borderline group, increasing to 0.67 in patients with severe dementia. When combining test results false positive rates decreased to 0.03 in patients with MMSE scores above 9.

CONCLUSION

Use of simple bedside tests of attention and organized thinking for the clinical diagnosis of DSD will result in high rates of false positive observations if used regardless of the severity of dementia. However, if test results are combined they may be useful to exclude DSD in patients with minimal to moderate degrees of dementia, but not in the severe group.

The neuropsychology of delirium: advancing the science of delirium assessment

OBJECTIVE

The diagnosis of delirium depends on eliciting its features through mental status examination and informant history. However, there is marked heterogeneity in how these features are assessed, from binary subjective clinical judgement to more comprehensive methods supported by cognitive testing. The aim of this article is to review the neuropsychological research in delirium and suggest future directions in research and clinical practice.

METHODS

We reviewed the neuropsychological literature on formal assessment and quantification of the different domains in delirium, focusing on the core feature of inattention.

RESULTS

Few studies have characterised and quantified the features of delirium using objective methods commonly employed in neuropsychological research. The existing evidence confirms that patients with delirium usually show impairments on objective tests of attention compared with cognitively intact controls and, in most cases, compared with patients with dementia. Further, abnormal level of arousal appears to be a specific indicator of delirium. The neuropsychological evidence base for impairments in other cognitive domains in delirium, including visual perception, language and thought processes, is small.

CONCLUSIONS

Delirium diagnosis requires accurate testing for its features, but there is little neuropsychological research examining the nature of these features, or evaluating the reliability, validity and discriminatory power of existing assessment processes. More research using the neuropsychological approach has enormous potential to improve and standardise delirium assessment methods of the individual features of delirium, such as inattention, and in developing more robust reference standards to enable greater comparability between studies.

Validation of the Brief Confusion Assessment Method for Screening Delirium in Elderly Medical Patients in a German Emergency Department

BACKGROUND

Delirium is frequent in elderly patients presenting in the emergency department (ED). Despite the severe prognosis, the majority of delirium cases remain undetected by emergency physicians (EPs). At the time of our study there was no valid delirium screening tool available for EDs in German-speaking regions. We aimed to evaluate the brief Confusion Assessment Method (bCAM) for a German ED during the daily work routine.

METHODS

We implemented the bCAM into practice in a German interdisciplinary high-volume ED and evaluated the bCAM's validity in a convenience sample of medical patients aged ≥ 70 years. The bCAM, which assesses four core features of delirium, was performed by EPs during their daily work routine and compared to a criterion standard based on the criteria for delirium as described in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition.

RESULTS

Compared to the criterion standard, delirium was found to be present in 46 (16.0%) of the 288 nonsurgical patients enrolled. The bCAM showed 93.8% specificity (95% confidence interval [CI] = 90.0%-96.5%) and 65.2% sensitivity (95% CI = 49.8%-78.7%). Positive and negative likelihood ratios were 10.5 and 0.37, respectively, while the odds ratio was 28.4. Delirium was missed in 10 of 16 cases, since the bCAM did not indicate altered levels of consciousness and disorganized thinking. The level of agreement with the criterion standard increased for patients with low cognitive performance.

CONCLUSION

This was the first study evaluating the bCAM for a German ED and when performed by EPs during routine work. The bCAM showed good specificity, but only moderate sensitivity. Nevertheless, application of the bCAM most likely improves the delirium detection rate in German EDs. However, it should only be applied by trained physicians to maximize diagnostic accuracy and hence improve the bCAM's sensitivity. Future studies should refine the bCAM.

Screening and detection of delirium in older ED patients: performance of the modified Confusion Assessment Method for the Emergency Department (mCAM-ED). A two-step tool

Delirium is frequent in older Emergency Department (ED) patients, but detection rates for delirium in the ED are low. To aid in identifying delirium, we developed and implemented a two-step systematic delirium screening and assessment tool in our ED: the modified Confusion Assessment Method for the Emergency Department (mCAM-ED). Components of the mCAM-ED include: (1) screening for inattention, the main feature of delirium, which was performed with the Months Backwards Test (MBT); (2) delirium assessment based on a structured interview with questions from the Mental Status Questionnaire by Kahn et al. and the Comprehension Test by Hart et al. The aims of our study are (1) to investigate the performance criteria of the mCAM-ED tool in a consecutive sample of older ED patients, (2) to evaluate the performance of the mCAM-ED in patients with and without dementia and (3) to test whether this tool is efficient in keeping evaluation time to a minimum and reducing screening and assessment burden on the patient. For this prospective validation study, we recruited a consecutive sample of ED patients aged 65 and older during an 11-day period in November 2015. Trained nurses assessed patients with the mCAM-ED. Results were compared to the reference standard [i.e. the geriatricians' delirium diagnosis based on the criteria of the Text Revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR)]. Performance criteria were computed. We included 286 consecutive ED patients aged 65 and older. The median age was 80.02 (Q₁ = 72.15; Q₃ = 86.76), 58.7% of included patients were female, 14.3% had dementia. We found a delirium prevalence of 7.0%. In patients with dementia, specificity and positive likelihood ratio were lower. When compared to the reference standard, delirium assessment with the mCAM-ED has a 0.98 specificity and a 39.9 positive likelihood ratio. In 80.0% of all cases, the first step of the mCAM-ED, i.e. screening for inattention with the MBT, took less than 30 s. On average, the complete mCAM-ED assessment required 3.2 (SD 2.0), 5.6 (SD 3.2), and 6.2 (SD 2.3) minutes in cognitively unimpaired patients, patients with dementia and patients with dementia or delirium, respectively. The mCAM-ED is able to efficiently rule out delirium as well as confirm the diagnosis of delirium in elderly patients with and without dementia and applies minimal screening and assessment burden on the patient.

Attention, arousal and other rapid bedside screening instruments for delirium in older patients: a systematic review of test accuracy studies

Objective

delirium occurs frequently in frail patients but is easily missed. Screening with a rapid, easy-to-use and highly sensitive instrument might help improve recognition. The aim of this study was to review attention, arousal and other rapid bedside screening instruments for delirium in older patients.

Methods

a literature search was performed in PubMed, PsycINFO and Embase. We scrutinized forward citations in Google Scholar, and references of included articles and prior reviews. We included studies among older patients that investigated the sensitivity and specificity of delirium screening instruments that could be administered in 3 min or less, and did not require surrogate information. We extracted study characteristics, risk of bias, sensitivity and specificity.

Results

we identified 27 studies among 4,766 patients in hospitals and nursing homes. They tested many different single and several combined screening instruments. Prevalence of delirium varied between 4% and 57%. Only one study scored a low risk of bias on all domains. Sensitivity varied between 17% and 100%, and specificity between 38% and 99%. Of the 22 tests with sensitivity ≥90%, seven also had specificity ≥80% in older patients in general. These results were approximately reproduced for the Observational Scale of Level of Arousal (OSLA) and Richmond Agitation and Sedation Scale (RASS): sensitivity and specificity were >80%.

Conclusion

two arousal tests-OSLA and RASS-had reproduced high sensitivity and specificity in older patients. Nurses can administer these tests during daily interaction with patients. Test accuracy studies about rapid screening tools for delirium superimposed on dementia were scarce.

The Diagnosis of Delirium Superimposed on Dementia: An Emerging Challenge

Delirium occurring in patients with dementia is referred to as delirium superimposed on dementia (DSD). People who are older with dementia and who are institutionalized are at increased risk of developing delirium when hospitalized. In addition, their prior cognitive impairment makes detecting their delirium a challenge. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and the International Statistical Classification of Diseases and Related Health Problems, 10th Revision are considered the standard reference for the diagnosis of delirium and include criteria of impairments in cognitive processes such as attention, additional cognitive disturbances, or altered level of arousal. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition and the International Statistical Classification of Diseases and Related Health Problems, 10th Revision does not provide guidance regarding specific tests for assessment of the cognitive process impaired in delirium. Importantly, the assessment or inclusion of preexisting cognitive impairment is also not addressed by these standards. The challenge of DSD gets more complex as types of dementia, particularly dementia with Lewy bodies, which has features of both delirium and dementia, are considered. The objective of this article is to critically review key elements for the diagnosis of DSD, including the challenge of neuropsychological assessment in patients with dementia and the influence of particular tests used to diagnose DSD. To address the challenges of DSD diagnosis, we present a framework for guiding the focus of future research efforts to develop a reliable reference standard to diagnose DSD. A key feature of a reliable reference standard will improve the ability to clinically diagnose DSD in facility-based patients and research studies.