Dissecting Delirium

The predictive value of confusion assessment method-intensive care unit and intensive care delirium screening checklist for delirium in critically ill patients in the intensive care unit: A systematic review and meta-analysis

BACKGROUND

Approximately 16%-89% of patients developed delirium during hospitalization in the intensive care unit (ICU). Studies on the accuracy and clinical application of ICU delirium screening tools exist, but the results are inconsistent. Moreover, the accuracy of different screening tools varied greatly.

AIM

To compare the diagnostic accuracy of Confusion Assessment Method-Intensive Care Unit (CAM-ICU) and Intensive Care Delirium Screening Checklist (ICDSC) for delirium screening in critically ill patients in the ICU.

STUDY DESIGN

We searched PubMed, Embase, Cochrane Central Register of Controlled Trials, Medline, and SciELO databases for relevant studies by combining relevant medical subject headings (MeSH) and keywords. Each database was searched from its creation to 30 January 2024. The included literature was screened by title, abstract, and full text. The diagnostic studies were summarized using Stata 14.0 software. SEN, SPE, PLR, NLR, DOR, and 95% confidence interval (CI) of the diagnostic studies were combined, the SROC analysis was performed, and the area under curve was estimated.

RESULTS

Thirty-two articles from the database met the inclusion criteria. The number of studies on CAM-ICU and ICDSC was 28 and 14, respectively. For CAM-ICU, the pooled sensitivity and specificity were 0.81 (95% CI: 0.81-0.81) and 0.94 (95% CI: 0.94-0.94), and the hierarchical SROC curve was 0.96 (95% CI: 0.93-0.97). Regarding the ICDSC, The pooled sensitivity and specificity were 0.79 (95% CI: 0.68-0.86) and 0.90 (95% CI: 0.84-0.93), and the hierarchical SROC curve was 0.92 (95% CI: 0.89-0.94). Regarding the likelihood ratio, the CAM-ICU has a high PLR of 14.24 (95% CI: 14.24-14.24) and a low NLR of 0.20 (95% CI: 0.20-0.20). The ICDSC has a low PLR of 7.64 (95% CI: 5.37-10.87) and a high NLR of 0.24 (95% CI: 0.16-0.35).

CONCLUSIONS

CAM-ICU showed good performance in terms of screening and diagnostic efficacies for delirium in critically ill patients. In view of the diagnostic accuracy of these two tools in delirium assessment, the strategies on how to increase their implementation in delirium screening among ICU patients are the focus of future research.

RELEVANCE FOR CLINICAL PRACTICE

CAM-ICU is recommended as the first choice to evaluate delirium in clinical practice, followed by ICDSC. Future studies can explore the predictive value of CAM-ICU and ICDSC in different special populations and different types of delirium.

Detection of delirium in older patients-A point prevalence study in surgical and non-surgical hospital wards

AIMS AND OBJECTIVES

To (i) determine the prevalence of delirium and identify delirium subtypes in surgical and non-surgical patients aged ≥65 years, (ii) determine whether certain precipitating factors affect the prevalence of delirium and (iii) review patients' medical records for description of delirium symptoms and the presence of International Classification of Diseases (ICD-10) coding for delirium in discharge summaries.

METHODOLOGICAL DESIGN AND JUSTIFICATIONS

Despite being a robust predictor of morbidity and mortality in older adults, delirium might be inadequately recognised and under-reported in patients' medical records and discharge summaries. A point prevalence study (24-h) of patients ≥65 years from surgical and non-surgical wards was therefore conducted in a tertiary university hospital.

ETHICAL ISSUES AND APPROVAL

The study was approved by the Data Protection Officer at the university hospital (2018/3454).

RESEARCH METHODS, INSTRUMENTS AND/OR INTERVENTIONS

Patients were assessed for delirium with 4AT and delirium subtypes with the Delirium Motor Subtype Scale. Information about room transfers, need and use of sensory aids and medical equipment was collected onsite. Patients' medical records were reviewed for description of delirium symptoms and of ICD-10 codes.

RESULTS

Overall, 123 patients were screened (52% female). Delirium was identified in 27% of them. Prevalence was associated with advanced age (≥85 years). The uncharacterised delirium subtype was most common (36%), followed by hypoactive (30%), hyperactive (24%) and mixed (9%). There were significant associations between positive screening tests and the need and use of sensory aids. Delirium symptoms were described in 58% of the patients who tested positive for delirium and the ICD-10 code for delirium was registered in 12% of these patients' discharge summaries.

CONCLUSIONS

The high prevalence of delirium and limited use of discharge codes highlight the need to improve the identification of delirium in hospital settings and at discharge. Increased awareness and detection of delirium in hospital settings are vital to improve patient care.

Towards experimental models of delirium utilizing zebrafish

Delirium is an acute neuropsychiatric condition characterized by impaired behavior and cognition. Although the syndrome has been known for millennia, its CNS mechanisms and risk factors remain poorly understood. Experimental animal models, especially rodent-based, are commonly used to probe various pathogenetic aspects of delirium. Complementing rodents, the zebrafish (Danio rerio) emerges as a promising novel model organism to study delirium. Zebrafish demonstrate high genetic and physiological homology to mammals, easy maintenance, robust behaviors in various sensitive behavioral tests, and the potential to screen for pharmacological agents relevant to delirium. Here, we critically discuss recent developments in the field, and emphasize the developing utility of zebrafish models for translational studies of delirium and deliriant drugs. Overall, the zebrafish represents a valuable and promising aquatic model species whose use may help understand delirium etiology, as well as develop novel therapies for this severely debilitating disorder.

Impact of a dementia-friendly program on detection and management of patients with cognitive impairment and delirium in acute-care hospital units: a controlled clinical trial design

Background

Frail older persons with cognitive impairment (CI) are at special risk of experiencing delirium during acute hospitalisation. The purpose of this study was to investigate whether a dementia-friendly hospital program contributes to improved detection and management of patients with CI and risk of delirium at an acute-care hospital in Norway. Furthermore, we aimed to explore whether the program affected the detection of delirium, pharmacological treatment, 30-day re-hospitalisation, 30-day mortality and institutionalisation afterwards.

Methods

This study was part of a larger quality improvement project aiming at developing and implementing a new program for early screening and management of patients with CI. This study, evaluating the program are designed as a controlled clinical trial with a historical control group. It was conducted at two different medical wards at a large acute-care hospital in Norway from September 2018 to December 2019. A total of 423 acute hospitalised patients 75 years of age or older were included in the study. Delirium screening and cognitive tests were recorded by research staff with the 4 ‘A’s Test (4AT) and the Confusion Assessment Measure (CAM), while demographic and medical information was recorded from the electronic medical records (EMR).

Results

Implementation of the dementia-friendly hospital program did not show any significant changes in the identification of patients with CI. However, the share of patients screened with 4AT within 24 h increased from 0% to 35.5% (P < .001). The proportion of the patients with CI identified by the clinical staff, who received measures to promote “dementia-friendly” care and reduce the risk for delirium increased by 32.2% (P < .001), compared to the control group. Furthermore, the number of patients with CI who were prescribed antipsychotic, hypnotic or sedative medications was reduced by 24.5% (P < .001). There were no differences in delirium detection, 30-day readmission or 30-day mortality.

Conclusions

A model for early screening and multifactorial non-pharmacological interventions for patients with CI and delirium may improve management of this patient group, and reduce prescriptions of antipsychotic, hypnotic and sedative medications. The implementation in clinical practice of early screening using quality improvement methodology deserves attention.

Trial registration

The protocol of this study was retrospectively registered in the ClinicalTrials.gov Protocol Registration and Results System with the registration number: NCT04737733 and date of registration: 03/02/2021.

Outcomes in heart failure patients discharged to skilled nursing facilities with delirium

AIM

Heart failure (HF) outcomes are disproportionately worse in patients discharged to skilled nursing facilities (SNF) as opposed to home. We hypothesized that dementia and delirium were key factors influencing these differences. Our aim was to explore the associations of dementia and delirium with risk of hospital readmission and mortality in HF patients discharged to SNF.

METHODS AND RESULTS

The study population included Veterans hospitalized for a primary diagnosis of HF and discharged to SNFs between 2010 and 2015. Pre-existing dementia was identified based on International Classification of Diseases-9 codes. Delirium was determined using the Minimum Data Set 3.0 Confusion Assessment Method algorithm. Proportional hazard regression analyses were used to model outcomes and were adjusted for covariates of interest. Patients (n = 21 655) were older (77.0 ± 10.5 years) and predominantly male (96.9%). Four groups were created according to presence (+) or absence (-) of dementia and delirium. Relative to the dementia-/delirium- group, the dementia-/delirium+ group was associated with increased 30 day mortality [adjusted hazard ratio (HR) = 2.2, 95% confidence interval (CI) = 1.7, 3.0] and 365 day mortality (adjusted HR = 1.5, 95% CI = 1.3, 1.7). Readmission was highest in the dementia-/delirium+ group after 30 days (HR = 1.2, 95% CI = 1.0, 1.5). In the group with dementia (delirium-/dementia+), 30 day mortality (12.8%; HR = 0.7, 95% CI = 0.7, 0.8) and readmissions (5.3%; HR = 1.0, 95% CI = 0.8, 1.1) were not different relative to the reference group.

CONCLUSIONS

Delirium, independent of pre-existing dementia, confers increased risk of hospital readmission and mortality in HF patients discharged to SNFs. Managing HF after hospitalization is a complex cognitive task and an increased focus on mental status in the acute care setting prior to discharge is needed to improve HF management and transitional care, mitigate adverse outcomes, and reduce healthcare costs.

Dynamic Delirium Severity Trajectories and Their Association With 2-Year Healthcare Utilization and Mortality Outcomes

Supplemental Digital Content is available in the text.

Delirium severity has been associated with a higher risk of mortality and an increasing morbidity burden. Recently defined delirium severity trajectories were predictive of 30-day mortality in a critically ill patient population. No studies to date have examined associations between delirium severity trajectories and 2-year mortality and healthcare utilization outcomes.

Delirium Severity Trajectories and Outcomes in ICU Patients. Defining a Dynamic Symptom Phenotype

Rationale: Delirium severity and duration are independently associated with higher mortality and morbidity. No studies to date have described a delirium trajectory by integrating both severity and duration.Objectives: The primary aim was to develop delirium trajectories by integrating symptom severity and duration. The secondary aim was to investigate the association among trajectory membership, clinical characteristics, and 30-day mortality.Methods: A secondary analysis of the PMD (Pharmacologic Management of Delirium) randomized control trial (ClinicalTrials.gov Identifier: NCT00842608; N = 531) was conducted. The presence of delirium and symptom severity were measured at least daily for 7 days using the Confusion Assessment Method for the intensive care unit (CAM-ICU) and CAM-ICU-7 (on a scale of 0-7, with 7 being the most severe). Delirium trajectories were defined using an innovative, data-driven statistical method (group-based trajectory modeling [GBTM]) and SAS v9.4.Results: A total of 531 delirious participants (mean age 60 yr [standard deviation = 16], 55% female, and 46% African American) were analyzed. Five distinct delirium trajectories were described (CAM-ICU-7: mean [standard deviation]); mild-brief (CAM-ICU-7: 0.5 [0.5]), severe-rapid recovers (CAM-ICU-7: 2.1 [1.0]), mild-accelerating (CAM-ICU-7: 2.2 [0.9]), severe-slow recovers (CAM-ICU-7: 3.9 [0.9]), and severe-nonrecovers (CAM-ICU-7: 5.9 [1.0]). Baseline cognition and race were associated with trajectory membership. Trajectory membership independently predicted 30-day mortality while controlling for age, sex, race, cognition, illness severity, and comorbidities.Conclusions: This secondary analysis described five distinct delirium trajectories based on delirium symptom severity and duration using group-based trajectory modeling. Trajectory membership predicted 30-day mortality.

Natural language processing to assess the epidemiology of delirium-suggestive behavioural disturbances in critically ill patients

Background: There is no gold standard approach for delirium diagnosis, making the assessment of its epidemiology difficult. Delirium can only be inferred though observation of behavioural disturbance and described with relevant nouns or adjectives. Objective: We aimed to use natural language processing (NLP) and its identification of words descriptive of behavioural disturbance to study the epidemiology of delirium in critically ill patients. Study design: Retrospective study using data collected from the electronic health records of a university-affiliated intensive care unit (ICU) in Melbourne, Australia. Participants: 12 375 patients Intervention: Analysis of electronic progress notes. Identification using NLP of at least one of a list of words describing behavioural disturbance within such notes. Results: We analysed 199 648 progress notes in 12 375 patients. Of these, 5108 patients (41.3%) had NLP-diagnosed behavioural disturbance (NLP-Dx-BD). Compared with those who did not have NLP-Dx-DB, these patients were older, more severely ill, and likely to have medical or unplanned admissions, neurological diagnosis, chronic kidney or liver disease and to receive mechanical ventilation and renal replacement therapy (P < 0.001). The unadjusted hospital mortality for NLP-Dx-BD patients was 14.1% versus 9.6% for patients without NLP-Dx-BD. After adjustment for baseline characteristics and illness severity, NLP-Dx-BD was not associated with increased risk of death (odds ratio [OR], 0.94; 95% CI, 0.80-1.10); a finding robust to multiple sensitivity, subgroups and time of observation subcohort analyses. In mechanically ventilated patients, NLP-Dx-BD was associated with decreased hospital mortality (OR, 0.80; 95% CI, 0.65-0.99) after adjustment for baseline severity of illness and year of admission. Conclusions: NLP enabled rapid assessment of large amounts of data identifying a population of ICU patients with typical high risk characteristics for delirium. Moreover, this technique enabled identification of previously poorly understood associations. Further investigations of this technique appear justified.

Diagnosis, prevention, and management of delirium in the intensive cardiac care unit

Delirium is a frequent complication in patients admitted to intensive cardiac care units (ICCU) with potentially severe consequences including increased risks of mortality, cognitive impairment and dependence at discharge, and longer times on mechanical ventilation and hospital stay. Delirium has been widely documented and studied in general intensive care units and in patients after cardiac surgery, but it has barely been studied in acute nonsurgical cardiac patients. Moreover, delirium (especially in its hypoactive form) is commonly misdiagnosed. We propose a protocol for delirium prevention and management in ICCUs. A daily comprehensive assessment to improve detection should be done using validated scales (ie, confusion assessment method). Preventive measures are particularly relevance and constitute the basis of treatment as well, acting on reversible risk factors, including environmental interventions, such as quiet time, sleep promotion, family support, communication, and adequate treatment of pain and dyspnea. Pharmacological prophylaxis is not indicated with the exception of patients at risk of withdrawal syndrome but should only be used in patients with confirmed delirium. Dexmedetomidine is the drug of choice in patients with severe agitation, and those weaning from invasive mechanical ventilation. As the complexity of ICCUs increases, clinical scenarios posing challenges for the management of delirium become more frequent. Efforts should be done to improve the identification of patients at risk during admission in order to establish preventive interventions to avoid this complication. Patient-centered protocols will increase the awareness of the healthcare professionals for better prevention and earlier diagnosis and will positively impact on prognosis.

Inadvertent Burst Suppression During Total Intravenous Anesthesia in 112 Consecutive Patients Undergoing Spinal Instrumentation Surgery: A Retrospective Observational Quality Improvement Project

INTRODUCTION

The incidence and quantification of inadvertent electroencephalographic burst suppression during total intravenous anesthesia (TIVA) for spine instrumentation surgery has not previously been reported.

METHODS

The primary aim of this retrospective observational quality improvement project was to establish the prevalence of burst suppression during spine instrumentation surgery with TIVA. The secondary outcome was the incidence of postoperative delirium.

RESULTS

One hundred twelve consecutive patients, aged between 20 and 88 years, underwent spinal instrumentation surgery. Seventy-eight (69.6%) patients experienced inadvertent burst suppression; the maximal degree of burst suppression ratio was 20% to 100%. Median (interquartile range [IQR]) time spent in burst suppression was 44 (77) minutes, and burst suppression was present for 22% (range: 2% to 93%) of the monitoring period. Average (±SD) propofol dose was lower in patients with burst suppression (87±19 vs. 93±15 µg/kg/min, P=0.04). Ten (8.9%) patients experienced postoperative delirium. Intraoperative burst suppression was more prevalent in those that experienced delirium (100% vs. 66.7%, P=0.03, relative risk: 1.5, 95% confidence interval: 1.3-1.7). The proportion of the monitoring period spent in maximal burst suppression (15.3 [25.9]% vs.11.7 [21.7]%) was similar between those that did, and did not, experience delirium.

CONCLUSIONS

High rates and prolonged periods of inadvertent burst suppression may be prevalent during spine instrumentation surgery with TIVA. Our findings suggest that usage of electroencephalography alone is incomplete without prompt interpretation and intervention, mandating close communication between neuromonitoring and anesthesia teams. The dose-response relationship between burst suppression, total time spent in maximal burst suppression, and their association with delirium warrants further evaluation.

Delirium prevalence point: an observational monocentric study in a tertiary university hospital

BACKGROUND

Delirium is a serious and common condition that needs an upgrade of the scientific and clinical attention.

AIM

To assess the delirium prevalence in an Italian university hospital.

METHODS

The monocentric 1-day observational study cohort has been conducted on March 15, 2018; the population was composed of adult hospitalized patients. All the eligible patients have been evaluated for the presence of delirium with the 4AT.

RESULTS

We enrolled 596 patients. Twenty-nine Acute and 3 Rehabilitation Units were involved in the study. The median age of the sample was 60 (IQR 48-74) and 52% (n = 313) were male. Patients from medical units were 42% (n = 252), from surgery units 41% (n = 249), and from rehabilitation units 15% (n = 95). Results of 4AT showed that 5.4% (n = 32) had delirium (4AT = 4), 12% (n = 73) had cognitive impairment (4AT = 1-3), and 82% (n = 491) had no delirium or cognitive impairment (4AT = 0). We found association between delirium and age, BMI, mortality at 30 days, and hospital mortality. Delirium was related with Barthel Index, dementia, and anticholinesterase inhibitors. About devices in use, we observed a correlation of delirium with central venous catheter, feeding tube, and urinary catheter. Physical restraints were also correlated to delirium.

CONCLUSIONS

We confirmed the presence of delirium across the hospital units, more in medical than in surgical ones. We found associations of delirium with conditions that limit movement, such as dementia, physical restraints, or devices. The development of delirium initiates a cascade of events culminating in the loss of independence and increased morbidity.

Safeguarding older adults with dementia, depression, and delirium in a temporary disaster shelter

Natural disasters impact people of every age in the communities where they occur, with older adults being a vulnerable subset of the population. Most disaster shelter volunteer nurses are experienced in addressing common health needs of older adult clients such as diabetes, hypertension, and pulmonary disease. These nurses also have the requisite training to respond to more acute medical events, including the symptoms of a heart attack or stroke. They provide care and comfort to those suffering from the distress, anxiety, and fear caused by disasters. However, they may be less adept at triaging and caring for older adults with mental health conditions such as delirium, depression, or dementia. The trauma associated with a disaster and relocation will challenge cognitive abilities in those with dementia, may exacerbate existing depression, or lead to the onset of delirium, which is a medical emergency. Older adults experiencing these conditions are at risk for harm and deterioration with serious short and long-term consequences. Since disaster shelter volunteer health care staff may not be well-versed in distinguishing between dementia, depression, or delirium, behavior observation, and safety considerations are critical determinants of whether it is possible to support the older adult in the shelter environment or it is necessary to transition to a higher level of care.

Delirium after cardiac surgery. Incidence, phenotypes, predisposing and precipitating risk factors, and effects

BACKGROUND

In cardiac surgical patients little is known about different phenotypes of delirium and how the symptoms fluctuate over time.

OBJECTIVES

Evaluate risk factors, incidence, fluctuations, phenotypic characteristics and impact on patients' outcomes of delirium.

METHODS

Prospective longitudinal study. In postoperative intensive care unit 199 patient were assessed three-times a day through an adapted versions of the Intensive Care Delirium Screening Checklist.

RESULTS

Delirium and subsyndromal delirium incidence were 30.7% and 31.2%, respectively. Delirium manifested mostly in the hypoactive form and showed a fluctuating trend for several days. Atrial fibrillation, benzodiazepine/opioids dosages, hearing impairment, extracorporeal circulation length, SAPS-II and mean arterial pressure were independent predictors for delirium. Delirium was a statistically significant predictor of chemical/physical restraint use and hospital length of stay.

CONCLUSIONS

Given the fluctuating and phenotypic characteristics, delirium screening should be a systematic/intentional activity. Multidisciplinary prevention strategies should be implemented to identify and treat the modifiable risk factors.

Management of delirium across an integrated health system

Facilitating throughput with systems thinking.

Geriatric Delirium Care: Using Chart Audits to Target Improvement Strategies

Background

Our hospital identified delirium care as a quality improvement target. Baseline characterization of our delirium care and deficits was needed to guide improvement efforts.

Methods

Two inpatient units were selected: 1) A general internal medicine unit with a focus on geriatrics, and 2) a surgical unit. Retrospective chart audits were conducted for all patients over age 50 admitted during a one-month period to compare delirium care with best practice guideline (BPG) recommendations, and to determine the incidence of missed cases of delirium and negative outcomes in patients with delirium. The aim was to gather local data to prioritize improvement efforts and mobilize stakeholders.

Results

186 charts were reviewed: 17 patients had physician-diagnosed delirium, 21 patients had missed delirium, and 148 patients had no delirium. Compliance with delirium BPGs was variable, but generally poor. There was a trend towards missed delirium and physician-diagnosed delirium being associated with greater odds of having above-median length of stay and lower odds of discharge home compared to no delirium diagnosis.

Conclusion

Overall, the chart audits confirmed delirium underrecognition and poor adherence to best practices in delirium management. Granular analysis of this data was used to mobilize stakeholders and prioritize improvement plans.