Assessing cognition in elderly patients presenting to the emergency department

Delirium detection in the emergency department: A diagnostic accuracy meta-analysis of history, physical examination, laboratory tests, and screening instruments

INTRODUCTION

Geriatric emergency department (ED) guidelines emphasize timely identification of delirium. This article updates previous diagnostic accuracy systematic reviews of history, physical examination, laboratory testing, and ED screening instruments for the diagnosis of delirium as well as test-treatment thresholds for ED delirium screening.

METHODS

We conducted a systematic review to quantify the diagnostic accuracy of approaches to identify delirium. Studies were included if they described adults aged 60 or older evaluated in the ED setting with an index test for delirium compared with an acceptable criterion standard for delirium. Data were extracted and studies were reviewed for risk of bias. When appropriate, we conducted a meta-analysis and estimated delirium screening thresholds.

RESULTS

Full-text review was performed on 55 studies and 27 were included in the current analysis. No studies were identified exploring the accuracy of findings on history or laboratory analysis. While two studies reported clinicians accurately rule in delirium, clinician gestalt is inadequate to rule out delirium. We report meta-analysis on three studies that quantified the accuracy of the 4 A's Test (4AT) to rule in (pooled positive likelihood ratio [LR+] 7.5, 95% confidence interval [CI] 2.7-20.7) and rule out (pooled negative likelihood ratio [LR-] 0.18, 95% CI 0.09-0.34) delirium. We also conducted meta-analysis of two studies that quantified the accuracy of the Abbreviated Mental Test-4 (AMT-4) and found that the pooled LR+ (4.3, 95% CI 2.4-7.8) was lower than that observed for the 4AT, but the pooled LR- (0.22, 95% CI 0.05-1) was similar. Based on one study the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is the superior instrument to rule in delirium. The calculated test threshold is 2% and the treatment threshold is 11%.

CONCLUSIONS

The quantitative accuracy of history and physical examination to identify ED delirium is virtually unexplored. The 4AT has the largest quantity of ED-based research. Other screening instruments may more accurately rule in or rule out delirium. If the goal is to rule in delirium then the CAM-ICU or brief CAM or modified CAM for the ED are superior instruments, although the accuracy of these screening tools are based on single-center studies. To rule out delirium, the Delirium Triage Screen is superior based on one single-center study.

Understanding why delirium is often missed in older emergency department patients: a qualitative descriptive study

OBJECTIVES

Unrecognized delirium is associated with significant adverse outcomes. Despite decades of effort and educational initiatives, validated screening tools have not improved delirium recognition in the emergency department (ED). There remains a fundamental knowledge gap of why it is consistently missed. The objective of this study was to explore the perceptions of ED physicians and nurses regarding factors contributing to missed delirium in older ED patients.

METHODS

We conducted a qualitative descriptive study at two academic tertiary care EDs in Toronto, Canada. Emergency physicians and nurses were interviewed by a trained qualitative researcher using a semi-structured interview guide. We coded transcripts with an iteratively developed codebook. Interviews were conducted until thematic saturation occurred. Thematic data analysis occurred in conjunction with data collection to continuously monitor emerging themes and areas for further exploration.

RESULTS

We interviewed 26 ED physicians and nurses. We identified key themes at four levels: clinical practice, provider attitudes, systematic processes, and education. The four themes include: (1) there are varied approaches to delirium recognition and infrequent use of screening tools; (2) delirium assessment is perceived as overly time consuming and of lower priority than other symptoms and syndromes; (3) it is unclear whose responsibility it is to recognize delirium; and (4) there is a need for a deeper or "functional" understanding of delirium that includes its consequences.

CONCLUSIONS

Our findings demonstrate a need for ED leadership to identify clear team roles for delirium recognition, standardize use of delirium screening tools, and prioritize delirium as a symptom of an acute medical emergency.

Delirium Prevention, Detection, and Treatment in Emergency Medicine Settings: A Geriatric Emergency Care Applied Research (GEAR) Network Scoping Review and Consensus Statement

BACKGROUND

Older adult delirium is often unrecognized in the emergency department (ED), yet the most compelling research questions to overcome knowledge-to-practice deficits remain undefined. The Geriatric Emergency care Applied Research (GEAR) Network was organized to identify and prioritize delirium clinical questions.

METHODS

GEAR identified and engaged 49 transdisciplinary stakeholders including emergency physicians, geriatricians, nurses, social workers, pharmacists, and patient advocates. Adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews, clinical questions were derived, medical librarian electronic searches were conducted, and applicable research evidence was synthesized for ED delirium detection, prevention, and management. The scoping review served as the foundation for a consensus conference to identify the highest priority research foci.

RESULTS

In the scoping review, 27 delirium detection "instruments" were described in 48 ED studies and used variable criterion standards with the result of delirium prevalence ranging from 6% to 38%. Clinician gestalt was the most common "instrument" evaluated with sensitivity ranging from 0% to 81% and specificity from 65% to 100%. For delirium management, 15 relevant studies were identified, including one randomized controlled trial. Some intervention studies targeted clinicians via education and others used clinical pathways. Three medications were evaluated to reduce or prevent ED delirium. No intervention consistently prevented or treated delirium. After reviewing the scoping review results, the GEAR stakeholders identified ED delirium prevention interventions not reliant on additional nurse or physician effort as the highest priority research.

CONCLUSIONS

Transdisciplinary stakeholders prioritize ED delirium prevention studies that are not reliant on health care worker tasks instead of alternative research directions such as defining etiologic delirium phenotypes to target prevention or intervention strategies.

The 4 'A's test for detecting delirium in acute medical patients: a diagnostic accuracy study

BACKGROUND

Delirium is a common and serious neuropsychiatric syndrome, usually triggered by illness or drugs. It remains underdetected. One reason for this is a lack of brief, pragmatic assessment tools. The 4 'A's test (Arousal, Attention, Abbreviated Mental Test - 4, Acute change) (4AT) is a screening tool designed for routine use. This project evaluated its usability, diagnostic accuracy and cost.

METHODS

Phase 1 - the usability of the 4AT in routine practice was measured with two surveys and two qualitative studies of health-care professionals, and a review of current clinical use of the 4AT as well as its presence in guidelines and reports. Phase 2 - the 4AT's diagnostic accuracy was assessed in newly admitted acute medical patients aged ≥ 70 years. Its performance was compared with that of the Confusion Assessment Method (CAM; a longer screening tool). The performance of individual 4AT test items was related to cognitive status, length of stay, new institutionalisation, mortality at 12 weeks and outcomes. The method used was a prospective, double-blind diagnostic test accuracy study in emergency departments or in acute general medical wards in three UK sites. Each patient underwent a reference standard delirium assessment and was also randomised to receive an assessment with either the 4AT (n = 421) or the CAM (n = 420). A health economics analysis was also conducted.

RESULTS

Phase 1 found evidence that delirium awareness is increasing, but also that there is a need for education on delirium in general and on the 4AT in particular. Most users reported that the 4AT was useful, and it was in widespread use both in the UK and beyond. No changes to the 4AT were considered necessary. Phase 2 involved 785 individuals who had data for analysis; their mean age was 81.4 (standard deviation 6.4) years, 45% were male, 99% were white and 9% had a known dementia diagnosis. The 4AT (n = 392) had an area under the receiver operating characteristic curve of 0.90. A positive 4AT score (> 3) had a specificity of 95% [95% confidence interval (CI) 92% to 97%] and a sensitivity of 76% (95% CI 61% to 87%) for reference standard delirium. The CAM (n = 382) had a specificity of 100% (95% CI 98% to 100%) and a sensitivity of 40% (95% CI 26% to 57%) in the subset of participants whom it was possible to assess using this. Patients with positive 4AT scores had longer lengths of stay (median 5 days, interquartile range 2.0-14.0 days) than did those with negative 4AT scores (median 2 days, interquartile range 1.0-6.0 days), and they had a higher 12-week mortality rate (16.1% and 9.2%, respectively). The estimated 12-week costs of an initial inpatient stay for patients with delirium were more than double the costs of an inpatient stay for patients without delirium (e.g. in Scotland, £7559, 95% CI £7362 to £7755, vs. £4215, 95% CI £4175 to £4254). The estimated cost of false-positive cases was £4653, of false-negative cases was £8956, and of a missed diagnosis was £2067.

LIMITATIONS

Patients were aged ≥ 70 years and were assessed soon after they were admitted, limiting generalisability. The treatment of patients in accordance with reference standard diagnosis limited the ability to assess comparative cost-effectiveness.

CONCLUSIONS

These findings support the use of the 4AT as a rapid delirium assessment instrument. The 4AT has acceptable diagnostic accuracy for acute older patients aged > 70 years.

FUTURE WORK

Further research should address the real-world implementation of delirium assessment. The 4AT should be tested in other populations.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN53388093.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 40. See the NIHR Journals Library website for further project information. The funder specified that any new delirium assessment tool should be compared against the CAM, but had no other role in the study design or conduct of the study.

Evaluation of the Ottawa 3DY as a screening tool for cognitive impairment in older emergency department patients

OBJECTIVE

This study sought to evaluate the implementation of the Ottawa 3DY Tool, a simple screening instrument for cognitive impairment, by front-line ED clinicians.

METHODS

We conducted a prospective cohort study in an academic ED. Patients ≥75 years underwent cognitive screening with the Ottawa 3DY by front-line nurses and physicians. Descriptive statistics were used to describe level of implementation and acceptability of the tool. Sensitivity and specificity was calculated using an Mini-Mental State Exam <25 as the cut-off for cognitive impairment. A weighted kappa was calculated to establish inter-rater agreement.

RESULTS

Cognitive screening was completed in 260/332 eligible patients (78.3%), who were 60% female and had a mean age of 83.7 years. Facilitators to screening: perceived importance and ownership of screening and feasibility of Ottawa 3DY. Barriers to screening were: over confidence in clinical judgement and perceived lack of patient benefit. Ottawa 3DY had a sensitivity of 84.6% (64.3-95.0) and specificity of 54.2% (39.3-68.4) when completed by nurses. When completed by emergency physicians, sensitivity was 78.9% (53.9-93.0) and specificity was 70.0% (45.7-87.2). Inter-rater agreement kappa score was 0.67.

DISCUSSION

This study demonstrated that incorporating the Ottawa 3DY tool into the routine evaluation of older ED patients by front-line ED clinicians is both feasible and effective. With its demonstrated good inter-rater reliability and moderate level of sensitivity and specificity when compared with the much longer MMSE, the routine adoption of this tool may help lead to improved recognition of cognitive impairment and ultimately patient and system outcomes.

Vital signs and impaired cognition in older emergency department patients: The APOP study

BACKGROUND/OBJECTIVES

Cognitive impairment is a frequent problem among older patients attending the Emergency Department (ED) and can be the result of pre-existing cognitive impairment, delirium, or neurologic disorders. Another cause can also be acute disturbance of brain perfusion and oxygenation, which may be reversed by optimal resuscitation. This study aimed to assess the relationship between vital signs, as a measure of acute hemodynamic changes, and cognitive impairment in older ED patients.

DESIGN

Prospective cohort study.

SETTING

ED's of two tertiary care and two secondary care hospitals in the Netherlands.

PARTICIPANTS

2629 patients aged 70-years and older.

MEASUREMENTS

Vital signs were measured at the moment of ED arrival as part of routine clinical care. Cognition was measured using the Six-Item Cognitive Impairment Test (6-CIT).

RESULTS

The median age of patients was 78 years (IQR 74-84). Cognitive impairment was present in 738 patients (28.1%). When comparing lowest with highest quartiles, a systolic blood pressure of <129 mmHg (OR 1.30, 95% confidence interval (95%CI) 0.98-1.73)was associated with increased risk of cognitive impairment. A higher respiratory rate (>21/min) was associated with increased risk of impaired cognition (OR 2.16, 95% CI 1.58-2.95) as well as oxygen saturation of <95% (OR 1.64, 95%CI 1.24-2.19).

CONCLUSION

Abnormal vital signs associated with decreased brain perfusion and oxygenation are also associated with cognitive impairment in older ED patients. This may partially be explained by the association between disease severity and delirium, but also by acute disturbance of brain perfusion and oxygenation. Future studies should establish whether normalization of vital signs will also acutely improve cognition.

The use of functional and cognitive assessment in the emergency department to inform decision making: A scoping review

BACKGROUND

The use of functional and/or cognitive assessment in the emergency department (ED) to inform decision making in the complex older adult is considered important, yet not routinely administered.

METHOD

Electronic databases were searched to identify eligible published research studies: older adults >65 years; the administration of a functional and/or cognition assessment instrument whilst the older adult is in any part of the ED; interventions resulting from the administration of the instrument; and a measured outcome post ED visit. A revised scoping review methodology was applied to chart study data and to identify key differences.

RESULTS

Ten research studies were identified that met the criteria for review. There are a variety of assessments, aimed at different age groups, for several purposes and used at different times in the ED journey. Assessments are not being used in conjunction with routine medical assessment early in the ED patient journey.

CONCLUSION

This scoping review identified no consistent suite of tools being administered in the ED to influence the disposition decision with measurable outcomes. Further research is required to identify a suite of assessment instruments suitable for use in the ED setting aimed at improving disposition decision making in the complex elderly person.

BET 1: Screening for delirium within the emergency department

A shortcut review was carried out to see if the abbreviated mental test score was better than other cognitive screening tools to diagnose delirium in the ED. Fourteen papers were identified reporting on 10 separate ED studies. Only one small study used the abbreviated mental test score and did not compare the diagnostic performance to any other test. There is very little published research on the use of the abbreviated mental test score in the ED setting.

Delirium Diagnostic and Screening Instruments in the Emergency Department: An Up-to-Date Systematic Review

BACKGROUND

Emergency care systems are at the core of modern healthcare and are the "point-of-entry/admission" into the hospital for many older/elderly patients. Among these, it is estimated that 15% to 30% will have delirium on admission and that over 50% will develop it during their stay. However, appropriate delirium diagnostic and screening still remains a critical area of need. The goal of this review is to update the field, exploring target areas in screening methods for delirium in the Emergency Department (ED), and/or acute care units, in the older population.

METHODS

A systematic review was conducted to search screening/diagnostic methods for delirium in the ED and/or acute care units within the ED.

RESULTS

Seven different scales were identified. Of the identified instruments, the Confusion Assessment Method (CAM) for the Intense Care Unit (CAM-ICU) was the most widely used. Of note, a brief two-step approach for delirium surveillance was defined with the Delirium Triage Screen (DTS) and the Brief Confusion Assessment Method (bCAM), and the diagnostic accuracy of the Richmond Agitation-Sedation Scale (RASS) for delirium had a good sensitivity and specificity in older patients.

CONCLUSION

The CAM-ICU appears as the potential reference standard for use in the ED, but research in a global approach of evaluation of actual and past cognitive changes is still warranted.

Prospective Validation of the Ottawa 3DY Scale by Geriatric Emergency Management Nurses to Identify Impaired Cognition in Older Emergency Department Patients

STUDY OBJECTIVE

Assessment of older emergency department (ED) patients with cognitive impairment is challenging because few tools exist that can be quickly administered by front-line practitioners. Our objective is to validate the Ottawa 3DY Scale, a 4-question screening tool for cognitive impairment, in older ED patients and compare its performance with that of the Animal Fluency Test.

METHODS

We conducted a prospective cohort study in 2 EDs and enrolled a convenience sample of patients aged 75 years or older with no history of cognitive impairment. Eligible patients were assessed by geriatric emergency management nurses who administered the Mini-Mental State Examination, ordered with the Ottawa 3DY Scale questions first, followed by the Animal Fluency Test. Mini-Mental State Examination score less than 25 was our criterion standard for cognitive impairment.

RESULTS

Study patients (N=238) had a mean age of 81.9 years and were 60.1% women, and 26.5% were admitted to the hospital. The Ottawa 3DY Scale and Mini-Mental State Examination were in agreement for 75.6% of cases, with a sensitivity of 93.8% (95% confidence interval [CI] 77.8% to 98.9%) and specificity of 72.8% (95% CI 66.1% to 78.7%). The Animal Fluency Test score less than 15 and Mini-Mental State Examination score were in agreement for 46.2% of cases, with sensitivity 90.6% (95% CI 73.8% to 97.5%) and specificity 39.3% (95% CI 32.7% to 46.4%).

CONCLUSION

Both the Ottawa 3DY Scale and the Animal Fluency Test demonstrated excellent sensitivity versus the Mini-Mental State Examination; however, the Animal Fluency Test exhibited poor specificity. The Ottawa 3DY Scale is an effective tool to screen for cognitive impairment in older ED patients, and its use may facilitate improved care in this vulnerable population.

The role of the dementia specialist nurse in acute care: a scoping review

AIMS AND OBJECTIVES

To identify the potential benefits of dementia specialist nursing and to inform the implementation of roles to support people with dementia during hospital admission.

BACKGROUND

Extended stays and adverse events mean that hospital admissions are costly for people with dementia, and patient experiences and outcomes can be poor. Specialist nurses have been identified as having potential to enhance care quality, reduce excess stays and reduce costs, but the evidence base for dementia specialist nurse roles has not previously been synthesised.

DESIGN

Scoping review.

DATA SOURCES

Cochrane Library, Campbell Collaboration, Clinical Evidence, Evidence-Based Medicine, York Centre for Reviews and Dissemination, PubMed, Medline, CINAHL and PsycInfo databases and internet searches and personal libraries/expert consultation to identify grey literature.

METHODS

Initial scoping searches were used to inform more focused systematic searches. Studies directly evaluating dementia nurse specialist roles or giving evidence of effectiveness of interventions/services that could be delivered by them to improve core outcomes were identified by one reviewer and verified by a second reviewer.

RESULTS

While direct evidence for the effectiveness of these roles is lacking, a number of areas were identified in which a nurse specialist role could make a contribution, including preventing adverse events and improving patient experiences and outcomes. There is a considerable body of evidence for the effectiveness of these interventions although the volume of evidence for specific interventions is not always significant.

CONCLUSIONS

The evidence indicates that a skilled dementia specialist nurse, undertaking a clearly defined role, and working directly with people with dementia and their carers for a significant proportion of the time, could benefit people with dementia in hospitals and their family carers.

RELEVANCE TO CLINICAL PRACTICE

Clear guidance for the development and implementation of dementia specialist nurse roles in acute hospital settings.

Melatonin and melatonin agonist for delirium in the elderly patients

The objective of this review is to summarize the available data on the use of melatonin and melatonin agonist for the prevention and management of delirium in the elderly patients from randomized controlled trials (RCTs). A systematic search of 5 major databases PubMed, MEDLINE, PsychINFO, Embase, and Cochrane Library was conducted. This search yielded a total of 2 RCTs for melatonin. One study compared melatonin to midazolam, clonidine, and control groups for the prevention and management of delirium in individuals who were pre- and posthip post-hip arthroplasty. The other study compared melatonin to placebo for the prevention of delirium in older adults admitted to an inpatient internal medicine service. Data from these 2 studies indicate that melatonin may have some benefit in the prevention and management of delirium in older adults. However, there is no evidence that melatonin reduces the severity of delirium or has any effect on behaviors or functions in these individuals. Melatonin was well tolerated in these 2 studies. The search for a melatonin agonist for delirium in the elderly patients yielded 1 study of ramelteon. In this study, ramelteon was found to be beneficial in preventing delirium in medically ill individuals when compared to placebo. Ramelteon was well tolerated in this study.

Screening for delirium in the emergency department: a systematic review

Older adults who visit emergency departments (EDs) often experience delirium, but it is infrequently recognized. A systematic review was therefore conducted to identify what delirium screening tools have been used in ED-based epidemiologic studies of delirium, whether there is a validated set of screening instruments to identify delirium among older adults in the ED or prehospital environments, and an ideal schedule during an older adult's visit to perform a delirium evaluation. MEDLINE/EMBASE, Cochrane, PsycINFO, and CINAHL databases were searched from inception through February 2013 for original, English-language research articles reporting on the assessment of older adults' mental status for delirium. Twenty-two articles met all study inclusion criteria. Overall, 7 screening instruments were identified, though only 1 has undergone initial validation for use in the ED environment and a second instrument is currently undergoing such validation. Minimal information was identified to suggest the ideal scheduling of a delirium assessment process to maximize the recognition of this condition in the ED. Study results indicate that several delirium screening tools have been used in investigations in the ED, though validation of these instruments for this particular environment has been minimal to date. The ideal interval(s) during which a delirium screening process should take place has yet to be determined. Research will be needed both to validate delirium screening instruments to be used for investigation and clinical care in the ED and to define the ideal timing and form of the delirium assessment process for older adults.

Nurse screening for delirium in older patients attending the emergency department

BACKGROUND

Delirium in older emergency department (ED) patients is common, associated with many adverse outcomes, and costly to manage. Delirium detection in the ED is almost universally poor.

OBJECTIVES

The authors aimed to develop a simple clinical risk screening tool that could be used by ED nurses as part of their initial assessment to identify patients at risk of delirium.

METHODS

A prospective cross-sectional study of patients 65 years and older attending a single ED.

RESULTS

Of 320 enrolled patients, 23 (7.2%) had delirium. Logistic regression analysis revealed 3 risk factors strongly associated with delirium risk: cognitive impairment, depression, and an abnormal heart rate/rhythm. Weighting these variables based on the strength of their association with delirium yielded a risk score from 0-4 inclusive. A cutoff of 2 or more in that score would have given a sensitivity of 87%, specificity of 70%, and NPV of 99%, while avoiding further diagnostic workup for delirium in approximately two-thirds of all patients, when used as an initial screen.

CONCLUSIONS

A simple risk screening tool using factors evident on initial nurse assessment can be used to identify patients at risk of delirium. Further trials are needed to test whether the tool improves patient outcomes.

Delirium within the emergency care setting, occurrence and detection: a systematic review

Recent recommendations from the Society for Academic Emergency Medicine and the American College of Emergency Physicians identified the detection of delirium in the emergency department (ED) as a 'high yield' research objective. This review aimed to determine the occurrence rate, and physician detection rates, of delirium within the ED. A systematic literature review was conducted and identified using online databases. Prospective cohort and cross-sectional studies from hospital EDs were interrogated. Systematic data extraction and assessments of quality were carried out. Searching yielded 723 publications, and 13 papers met inclusion criteria. Occurrence of delirium at admission to the ED ranged from 7% to 20% of patients. Physician diagnosis rates of preconfirmed delirium (using a specified tool) within the ED varied between 11.1% and 46.0%. Many studies used non-validated assessment tools to gather data. Four delirium outcome studies were conducted in the ED setting. Results vary, with several being of poor quality; however, delirium at ED presentation may have a significant effect on long-term outcomes. Delirium is a significant concern in the ED, with many delirious patients not identified by physicians. Given the scale, addressing delirium should be a priority for clinicians and researchers. To improve delirium outcomes and hospital management, measures must include mechanisms to improve detection. Finding a single validated assessment method and facilitating research in this difficult patient population would be an important progress.

Contextual factors influencing success or failure of emergency department interventions for cognitively impaired older people: a scoping and integrative review

AIM

This paper is a report of a scoping review of research on cognitive impairment in older adults who visit Emergency Departments of acute care hospitals, followed by an integrative review that included a quality assessment to determine the effectiveness of interventions for this population.

BACKGROUND

Being old and cognitively impaired in the Emergency Department--a fast-paced intervention system--is a complex phenomenon that challenges many healthcare professionals. The rise in the incidence and prevalence of dementia will have a large impact on healthcare systems.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, PsycInfo, AgeLine, Abstracts in Social Gerontology, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials and Google Scholar between 1990 and 2008, for qualitative or quantitative studies reporting extractable data on delirium or dementia in non-institutionalized older people (65+ years) in the Emergency Department.

REVIEW METHODS

Titles screened by a project researcher and checked against inclusion criteria by another researcher. Two reviewers completed independent data extraction and synthesis of included studies. Quality assessment occurred using the Critical Appraisal Skills Programme Tools.

RESULTS

Fifteen studies met the inclusion criteria for integrative review. Analysis of these studies indicates that the prevalence of cognitive impairment is high and improvements are needed. Contextual details and relevant features of an appropriate intervention are poorly explained.

CONCLUSION

Although the prevalence and incidence of cognitive impairment is recognized, appropriate interventions and programmatic responses remain elusive. Quality improvements require more thorough examination of emergency department context to identify modifiable influencing factors that are transferable across settings.