Subsyndromal delirium in the ICU: evidence for a disease spectrum

Prevalence and risk factors of subsyndromal delirium in ICU: A systematic review and meta-analysis

OBJECTIVE

To systematically assess the prevalence and risk factors for subsyndromal delirium (SSD) in the intensive care unit.

DESIGN

A systematic reviewand meta-analysis.

METHODOLOGY

This systematic review and meta-analysis was conducted in eight databases, including PubMed, Web of Science, Ovid,Scopus, China Knowledge Resource Integrated Database, Wanfang Database,Weipu Database and Chinese Biomedical Database. All original observational studies of subsyndromal delirium in the ICU were included, with languages limited to English and Chinese. The methodological quality was assessed by the Newcastle-Ottawa Scale and the Agency for Healthcare Research and Quality recommendation checklist. Meta-analysis was performed using Stata software (version 18.0).

RESULT

A total of 27 studies involving 7,286 participants were included in this review. The pooled prevalence of SSD was 32.4 % (95 %CI: 27.1 %-37.7 %).Fourteen studies reported 34 independent risk factors, and the following ten factors were significantly associated with SSD: older age, higher Acute Physiology and Chronic Health Evaluation II (APACHE II) score, lower Mini-mental Status Examination (MMSE) score, pain, mechanical ventilation, hypoproteinemia, blood transfusion, longer ICU stay, infection, and physical restraint.

CONCLUSION

We conducted a systematic review and meta-analysis to evaluate the prevalence of SSD in the ICU and identified 10 risk factors associated with SSD. However, the studies have significant heterogeneity, future research should be conducted in multicenter with large samples to strengthen the current evidence.

IMPLICATIONS FOR CLINICAL PRACTICE

Subsyndromal delirium is a frequently occurring adverse event in the ICU, so it is recommended that clinicians and nurses incorporate the assessment of SSD into their daily routine. In this study, we also identified ten risk factors associated with SSD, and some of which could be modified or intervened. These findings provide a basis for ICU medical staff to identify patients at high risk of SSD and then implement individualized interventions to reduce the prevalence of SSD.

Incidence and influencing factors of subsyndromal delirium in elderly patients with pancreatic surgery: a prospective study

Objective

To prospectively investigatethe incidence and influencing factors of Subsyndromal delirium (SSD) in elderly patients undergoing pancreatic surgery.

Methods

According to a prospective observational study, elderly patients (aged ≥60 years) who underwent pancreatic surgery in the pancreatic center of our hospital from August 2023 to February 2024 were selected. Patients were divided into SSD and Normal groups based on the evaluation of the Delirium Rating Scale-revised-98 in the first 1-4 days postoperatively. Multivariate logistic regression was performed to determine the influencing factors, and subject operating characteristic curves were used to assess the predictive effect of risk factors for subsyndromal delirium.

Results

A total of 179 elderly pancreatic surgery patients were included in this study. 67 elderly patients developed subsyndromal delirium with an incidence of 37.43%. Multivariable Logistic regression revealed that risk factors for SSD included age, age-adjusted Charlson Comorbidity Index (aCCI), and postoperative fever, while and education level with senior high school or above was found to be protective factors. Receiver operating characteristic (ROC) curve showed that the combination of age and aCCI predicted SSD in elderly pancreatic surgery patients (Area Under Curve = 0.815, 95% Confidence Interval: 0.752 - 0.878), with sensitivity and specificity of 80.6% and 75.9%, respectively.

Conclusion

The incidence of subsyndromal delirium after elderly pancreatic surgery was as high as 37.43%. Effective assessment and prevention of subsyndromal delirium are crucial. In the early postoperative period, special attention should be given to elderly patients with more preoperative comorbidities and lower education levels, and their temperature should be monitored in a timely manner.

Delirium at the intensive care unit and long-term survival: a retrospective study

BACKGROUND

Delirium is a common complication in patients at the intensive care unit (ICU) and is associated with prolonged ICU-stay and hospitalization and with increased morbidity. The impact of ICU-delirium on long-term survival is not clearly understood.

METHODS

This retrospective single center observational study was conducted at the Institute of Intensive Care Medicine at the University Hospital Zurich, Switzerland. All adult ICU-survivors over a four-year period were screened for eligibility. ICU-delirium was defined based on the Intensive Care Delirium Screening Checklist (ICDSC), together with the coded diagnosis F05 in the International Classification of Diseases (ICD-2019). ICU-survivors who developed delirium during their ICU stay (group D) were compared with ICU-survivors who did not (group ND). Survival was evaluated according to data from hospital electronic health records up to four years from ICU-discharge. The survival analysis was reported using Kaplan-Meier curves and absolute risk differences (ARD). A multivariable logistic regression model was fitted with long-term survival at four years after ICU-discharge as outcome of interest, including several clinical conditions and interventions associated with long-term survival for ICU patients. For subgroup analysis, ICU-survivors were grouped based on age at the time of admission (45-54, 55-64, ≥ 65 years), and on relevant clinical conditions.

RESULTS

A total of 9'604 patients fulfilled the inclusion criteria, of them 22.6% (n = 2'171) developed ICU-delirium. Overall, patients in the group D had a significantly lower probability of survival than patients in the group ND (p < 0.0001, ARD = 11.8%). In the multivariable analysis, ICU-delirium was confirmed as independently associated with long-term survival. After grouping for age categories, patients between 55 and 64 years of age in the group D were less likely to survive than patients in the group ND at every time point analyzed, up to four years after ICU discharge (p < 0.001, ARD = 7.3%). This difference was even more significant in the comparison between patients over 65 years (p < 0.0001, ARD 11.1%). No significant difference was observed in the other age groups.

CONCLUSIONS

In the study population, ICU-delirium was independently associated with a reduced long-term survival. Patients who developed ICU-delirium had a reduced survival up to four years after ICU discharge and this association was particularly evident in patients above 55 years of age.

Association between delirium severity and prognosis following Transcatheter aortic valve implantation

BACKGROUND

Delirium is associated with patient prognosis after transcatheter aortic valve implantation (TAVI). However, the prognostic impact of subsyndromal delirium, described as an intermediate stage between delirium and normal cognition, is uncertain. The present study aimed to investigate the prognostic impact of delirium severity in patients undergoing TAVI.

METHODS AND RESULTS

We prospectively assessed the delirium status of 1617 consecutive patients who underwent TAVI at Kokura Memorial Hospital using the Intensive Care Delirium Screening Checklist (ICDSC). The patients were divided into the following three groups: no-delirium [ICDSC score 0, n = 1035 (64.0 %)], subsyndromal delirium [ICDSC 1-3, n = 348 (21.5 %)], and delirium [ICDSC 4-8, n = 234 (14.5 %)] groups. A worse delirium status was associated with older age, higher degree of frailty, and higher prevalence of comorbidities, including atrial fibrillation, dementia, and peripheral arterial disease. At 2 years post-procedure with a clinical follow-up rate of 92.6 %, the cumulative all-cause mortality rate was significantly higher in the subsyndromal delirium (21.8 %) (p < 0.001) and delirium (29.1 %) (p < 0.001) groups than in the no-delirium group (11.9 %). After adjusting for pre- and post-procedural confounders, subsyndromal delirium and delirium were associated with an increased mortality risk [adjusted hazard ratio (HR) for subsyndromal delirium, 1.38; 95 % CI, 1.00-1.90; p = 0.049; adjusted HR for delirium, 1.61; 95 % CI, 1.15-2.17; p = 0.006].

CONCLUSIONS

Delirium conditions, including delirium and subsyndromal delirium, occurred in more than one-third of patients who had undergone TAVI and were associated with increased mortality.

Development and Validation of a Routine Electronic Health Record-Based Delirium Prediction Model for Surgical Patients Without Dementia: Retrospective Case-Control Study

BACKGROUND

Postoperative delirium (POD) is a common complication after major surgery and is associated with poor outcomes in older adults. Early identification of patients at high risk of POD can enable targeted prevention efforts. However, existing POD prediction models require inpatient data collected during the hospital stay, which delays predictions and limits scalability.

OBJECTIVE

This study aimed to develop and externally validate a machine learning-based prediction model for POD using routine electronic health record (EHR) data.

METHODS

We identified all surgical encounters from 2014 to 2021 for patients aged 50 years and older who underwent an operation requiring general anesthesia, with a length of stay of at least 1 day at 3 Indiana hospitals. Patients with preexisting dementia or mild cognitive impairment were excluded. POD was identified using Confusion Assessment Method records and delirium International Classification of Diseases (ICD) codes. Controls without delirium or nurse-documented confusion were matched to cases by age, sex, race, and year of admission. We trained logistic regression, random forest, extreme gradient boosting (XGB), and neural network models to predict POD using 143 features derived from routine EHR data available at the time of hospital admission. Separate models were developed for each hospital using surveillance periods of 3 months, 6 months, and 1 year before admission. Model performance was evaluated using the area under the receiver operating characteristic curve (AUROC). Each model was internally validated using holdout data and externally validated using data from the other 2 hospitals. Calibration was assessed using calibration curves.

RESULTS

The study cohort included 7167 delirium cases and 7167 matched controls. XGB outperformed all other classifiers. AUROCs were highest for XGB models trained on 12 months of preadmission data. The best-performing XGB model achieved a mean AUROC of 0.79 (SD 0.01) on the holdout set, which decreased to 0.69-0.74 (SD 0.02) when externally validated on data from other hospitals.

CONCLUSIONS

Our routine EHR-based POD prediction models demonstrated good predictive ability using a limited set of preadmission and surgical variables, though their generalizability was limited. The proposed models could be used as a scalable, automated screening tool to identify patients at high risk of POD at the time of hospital admission.

Pharmacological and non-pharmacological prevention and management of delirium in critically ill and palliative patients in the inpatient setting: a review

Introduction

This review explores delirium in critically ill patients in the inpatient setting, focusing on its prevention and management. It evaluates the efficacy of both current pharmacological and non-pharmacological interventions, aiming to provide a comprehensive overview.

Methods

A systematic literature search was conducted to identify relevant studies investigating the prevention and management of delirium resulting in a final sample of 26 articles for analysis.

Results

Of the 26 articles analyzed for this review (N = 8,831 participants) of controlled trials, 16 studies examined the prevention of delirium, 9 explored the treatment of delirium, and 1 investigated both prevention and treatment of delirium.

Discussion

Among the reviewed studies, there is evidence that non-pharmacologic methods are effective in the prevention of delirium. Evidence regarding pharmacological interventions for delirium prevention is varied and inconclusive, with some indication that atypical antipsychotics like aripiprazole and quetiapine may reduce the incidence of delirium. Regarding the treatment of delirium, there is limited evidence supporting the use of pharmacological agents. Additional double-blinded, randomized, placebo-controlled clinical trials are needed to investigate the efficacy of pharmacologic agents for diverse hospitalized populations.

Preventive Effects of Ramelteon, Suvorexant, and Lemborexant on Delirium in Hospitalized Patients With Physical Disease: A Retrospective Cohort Study

BACKGROUND

New sleep-inducing drugs (eg, ramelteon, suvorexant, and lemborexant) have been shown to prevent delirium in high-risk groups. However, no single study has simultaneously evaluated the delirium-preventing effects of all novel sleep-inducing drugs in hospitalized patients. Therefore, this study aimed to clarify the relationship between sleep-inducing drugs and delirium prevention in patients hospitalized in general medical-surgical settings for nonpsychiatric conditions who underwent liaison interventions for insomnia.

METHODS

This retrospective cohort study included patients treated in general medical-surgical settings for nonpsychiatric conditions with consultation-liaison psychiatry consult for insomnia. Delirium was diagnosed by fully certified psychiatrists using the Diagnostic and Statistical Manual of Mental Disorders 5 th edition. The following items were retrospectively examined from medical records as factors related to delirium development: type of sleep-inducing drugs, age, sex, and delirium risk factors. The risk factors of delirium development were calculated using adjusted odds ratios (aORs) via multivariate logistic regression analysis.

RESULTS

Among the 710 patients analyzed, 257 (36.2%) developed delirium. Suvorexant (aOR, 0.61; 95% confidence interval [CI], 0.40-0.94; P = 0.02) and lemborexant (aOR, 0.23; 95% CI, 0.14-0.39; P < 0.0001) significantly reduced the risk of developing delirium. Benzodiazepines (aOR, 1.90; 95% CI, 1.15-3.13; P = 0.01) significantly increased this risk. Ramelteon (aOR, 1.30; 95% CI, 0.84-2.01; P = 0.24) and Z-drugs (aOR, 1.27; 95% CI, 0.81-1.98; P = 0.30) were not significantly associated with delirium development.

CONCLUSIONS

The use of suvorexant and lemborexant may prevent delirium in patients with a wide range of medical conditions.

Effect of Atypical Sleep EEG Patterns on Weaning From Prolonged Mechanical Ventilation

BACKGROUND

Approximately one-third of acute ICU patients display atypical sleep patterns that cannot be interpreted by using standard EEG criteria for sleep. Atypical sleep patterns have been associated with poor weaning outcomes in acute ICUs.

RESEARCH QUESTION

Do patients being weaned from prolonged mechanical ventilation experience atypical sleep EEG patterns, and are these patterns linked with weaning outcomes?

STUDY DESIGN AND METHODS

EEG power spectral analysis during wakefulness and overnight polysomnogram were performed on alert, nondelirious patients at a long-term acute care facility.

RESULTS

Forty-four patients had been ventilated for a median duration of 38 days at the time of the polysomnogram study. Eleven patients (25%) exhibited atypical sleep EEG. During wakefulness, relative EEG power spectral analysis revealed higher relative delta power in patients with atypical sleep than in patients with usual sleep (53% vs 41%; P < .001) and a higher slow-to-fast power ratio during wakefulness: 4.39 vs 2.17 (P < .001). Patients with atypical sleep displayed more subsyndromal delirium (36% vs 6%; P = .027) and less rapid eye movement sleep (4% vs 11% total sleep time; P < .02). Weaning failure was more common in the atypical sleep group than in the usual sleep group: 91% vs 45% (P = .013).

INTERPRETATION

This study provides the first evidence that patients in a long-term acute care facility being weaned from prolonged ventilation exhibit atypical sleep EEG patterns that are associated with weaning failure. Patients with atypical sleep EEG patterns had higher rates of subsyndromal delirium and slowing of the wakeful EEG, suggesting that these two findings represent a biological signal for brain dysfunction.

Delirium and delirium severity screening in the intensive care-correspondence of screenings tools

BACKGROUND

Delirium severity scores are gaining acceptance for measuring delirium in the intensive care unit (ICU).

OBJECTIVE

The aim of this study was to evaluate the concordance between the Confusion Assessment Method for the intensive care unit (CAM-ICU)-7 and the Intensive Care Delirium Screening Checklist (ICDSC) as delirium severity measurement tools.

METHODS

This was a prospective, comparative, observational multicentre study. This study was conducted in 18 Danish ICUs. Delirium was assessed in adult critically ill patients admitted to an ICU with a Richmond Agitation and Sedation Score (RASS) of -2 or above. ICU nurses assessed delirium with randomised paired delirium screening instruments, using the CAM-ICU, the ICDSC, and the CAM-ICU-7. The correlation between the CAM-ICU-7 and the ICDSC severity scores was evaluated for all predefined patient subgroups.

RESULTS

A total of 1126 paired screenings were conducted by 127 ICU nurses in 850 patients. The patients' median age was 70 years (interquartile range: 61-77), 40% (339/850) were female, and 54% (457/850) had at least one positive delirium score. Delirium severity ranges (CAM-ICU-7: 0-7; and ICDSC: 0-8) were positively correlated (Pearson's correlation coefficient, r = 0.83; p < 0.0001). The overall agreement between the CAM-ICU-7 and the ICDSC for delirium measurement (CAM-ICU-7: >2, and ICDSC: >3) was substantial (kappa = 0.74), but the agreement decreased to fair (kappa = 0.38) if a patient had a RASS less than 0.

CONCLUSIONS

The agreement between the CAM-ICU-7 and the ICDSC for delirium severity measurement was substantial but might be affected by the patient's sedation and agitation level at the time of assessment.

IMPLICATIONS FOR PRACTICE

Both CAM-ICU-7 and ICDSC can be implemented for delirium severity measurement. Attention is warranted in both scores if a patient has a RASS of -2.

Assessment and report of individual symptoms in studies of delirium in postoperative populations: a systematic review

OBJECTIVES

Delirium is most often reported as present or absent. Patients with symptoms falling short of the diagnostic criteria for delirium fall into 'no delirium' or 'control' groups. This binary classification neglects individual symptoms and may be hindering identification of the pathophysiology underlying delirium. This systematic review investigates which individual symptoms of delirium are reported by studies of postoperative delirium in adults.

METHODS

Medline, EMBASE and Web of Science databases were searched on 03 June 2021 and 06 April 2023. Two reviewers independently examined titles and abstracts. Each paper was screened in duplicate and conflicting decisions settled by consensus discussion. Data were extracted, qualitatively synthesised and narratively reported. All included studies were quality assessed.

RESULTS

These searches yielded 4,367 results. After title and abstract screening, 694 full-text studies were reviewed, and 62 deemed eligible for inclusion. This review details 11,377 patients including 2,049 patients with delirium. In total, 78 differently described delirium symptoms were reported. The most reported symptoms were inattention (N = 29), disorientation (N = 27), psychomotor agitation/retardation (N = 22), hallucination (N = 22) and memory impairment (N = 18). Notably, psychomotor agitation and hallucinations are not listed in the current Diagnostic and Statistical Manual for Mental Disorders-5-Text Revision delirium definition.

CONCLUSIONS

The 78 symptoms reported in this systematic review cover domains of attention, awareness, disorientation and other cognitive changes. There is a lack of standardisation of terms, and many recorded symptoms are synonyms of each other. This systematic review provides a library of individual delirium symptoms, which may be used to inform future reporting.

Modification in ICU Design May Affect Delirium and Circadian Melatonin: A Proof of Concept Pilot Study

OBJECTIVES

Nonpharmacologic delirium management is recommended by current guidelines, but studies on the impact of ICU design are still limited. The study's primary purpose was to determine if a multicomponent change in room design prevents ICU delirium. Second, the influence of lighting conditions on serum melatonin was assessed.

DESIGN

Prospective observational cohort pilot study.

SETTING

The new design concept was established in two two-bed ICU rooms of a university hospital. Besides modifications aimed at stress relief, it includes a new dynamic lighting system.

PATIENTS

Seventy-four adult critically ill patients on mechanical ventilation with an expected ICU length of stay of at least 48 hours, treated in modified or standard rooms.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The clinical examination included a prospective assessment for depth of sedation, delirium, and pain every 8 hours using validated scores. Blood samples for serum melatonin profiles were collected every 4 hours for a maximum of three 24-hour periods. Seventy-four patients were included in the analysis. Seventy-six percent ( n = 28) of patients in the standard rooms developed delirium compared with 46% of patients ( n = 17) in the modified rooms ( p = 0.017). Patients in standard rooms (vs. modified rooms) had a 2.3-fold higher delirium severity (odds ratio = 2.292; 95% CI, 1.582-3.321; p < 0.0001). Light intensity, calculated using the measure of circadian effective irradiance, significantly influenced the course of serum melatonin ( p < 0.0001). Significant interactions ( p < 0.001) revealed that differences in serum melatonin between patients in standard and modified rooms were not the same over time but varied in specific periods of time.

CONCLUSIONS

Modifications in ICU room design may influence the incidence and severity of delirium. Dedicated light therapy could potentially influence delirium outcomes by modulating circadian melatonin levels.

Prolonged delirium during hospitalization is associated with worse long-term and short-term outcomes in patients with acute heart failure

BACKGROUND

The association between prolonged delirium during hospitalization and long-term prognosis in patients with acute heart failure (AHF) admitted to the cardiac intensive care unit (CICU) has not been fully elucidated.

METHODS

We conducted a prospective registry study of patients with AHF admitted to the CICU at 2 hospitals from 2013 to 2021. We divided study patients into 3 groups according to the presence or absence of delirium and prolonged delirium as follows: no delirium, resolved delirium, or prolonged delirium. Main outcomes were in-hospital mortality and 3-year mortality after discharge.

RESULTS

A total of 1555 patients with AHF (median age, 80 years) were included in the analysis. Of these, 406 patients (26.1%) developed delirium. We divided patients with delirium into 2 groups: the resolved delirium group (n = 201) or the prolonged delirium group (n = 205). Multivariate Cox proportional hazards models for long-term prognosis demonstrated that the prolonged delirium group had a higher incidence of all-cause death (hazard ratio [HR], 1.52; 95% CI, 1.08 to 2.14) and non-cardiovascular death (HR, 1.84; 95% CI, 1.21 to 2.78) than the resolved delirium group. Regarding in-hospital outcomes, multivariate logistic regression modeling showed that prolonged delirium is associated with all-cause death (odds ratio [OR], 9.55; 95% confidential interval [CI], 2.99 to 30.53) and cardiovascular death (OR, 13.02; 95% CI, 2.86 to 59.27) compared with resolved delirium.

CONCLUSIONS

Prolonged delirium is associated with worse long-term and short-term outcomes than resolved delirium in patients with AHF.

Recurrent delirium episodes within the intensive care unit: Incidence and associated factors

PURPOSE

Describe the incidence and factors associated with recurrent delirium in the intensive care unit (ICU).

MATERIALS AND METHODS

Retrospective study of ICU patients diagnosed with delirium. Delirium clearance defined as 48 h of negative delirium assessments following initial episode and recurrent delirium as any positive delirium assessment following clearance. Multivariable logistic regression model assessed independent association of patient and hospital factors on development of recurrent delirium, adjusting for pre-defined covariates.

RESULTS

Among 8591 ICU admissions identified with delirium, 1067 (12.4%) had recurrent symptoms. Factors associated with increased odds of recurrent delirium were age (nonlinear; p = 0.02), shock (OR 1.45, 95% CI [1.20, 1.75]), admission to medical (OR 3.25, 95% CI [2.42, 4.37]), surgical (OR 3.00, 95% CI [2.21, 4.06]), or trauma (OR 2.17, 95% CI [1.58, 3.00]) ICU vs. cardiovascular ICU, increased duration of mechanical ventilation (OR 2.43, 95% CI [2.22, 2.65]), propofol use (OR 1.35, 95% CI [1.02, 1.80]), and antipsychotic medications (haloperidol OR 1.53, 95% CI [1.26, 1.86]; quetiapine OR 2.45, 95% CI [1.98, 3.02]; and olanzapine OR 1.54, 95% CI [1.25, 1.88]).

CONCLUSIONS

Over 10% of delirious ICU patients had recurrent symptoms. Factors associated with recurrence included age, duration of mechanical ventilation and medication exposure.

CLINICAL TRIAL NUMBER

Not applicable.

The risk factors for and the frequency and outcomes of subsyndromal delirium among patients who have undergone cardiac surgery: a protocol for systematic review and meta-analysis

INTRODUCTION

Several key symptoms must be present for the accurate diagnosis of patients with postoperative cardiac delirium. Some patients present with symptoms of delirium but do not meet the diagnostic criteria for delirium; such individuals are considered to have having subsyndromal delirium (SSD). SSD is associated with misdiagnosis and poor outcomes. However, to date, no systematic review (SR) has examined the frequency of, risk factors for, and outcomes of SSD among adults who have undergone cardiac surgery.

METHODS AND ANALYSIS

The aim of this SR is to identify those studies that have explored SSD after cardiac surgery. MeSH and free entry terms associated with "subsyndromal delirium" and "subclinical delirium" will be used to search for relevant studies. The PubMed, Web of Science, OVID, Cochrane Library, CINAHL, EMBASE, PsycINFO, China National Knowledge Infrastructure, Wanfang data, VIP database and SinoMed will be searched from inception to the date of retrieval without any restrictions. The primary outcomes will be the frequency of SSD, the risk factors for SSD, and the outcomes of SSD. Analyses will be performed using STATA V.16.0, and descriptive analyses will be performed if the data are not suitable for meta-analysis (ie, data with significant heterogeneity or from different comparisons).

ETHICS AND DISSEMINATION

The SR will examine the frequency of, risk factors for and outcomes of SSD in adults who have undergone cardiac surgery. The results will provide guidance for the identification of knowledge gaps in this field, and areas for further research will be highlighted. The review protocol will be submitted for publication in peer-reviewed journals for dissemination of the findings. Individual patient data will not be included in this protocol, so ethical approval will not be needed.

PROSPERO REGISTRATION NUMBER

CRD42022379211.

Intensive care unit nurses' perception of three different methods for delirium screening: A survey (DELIS-3)

BACKGROUND

Delirium is common in critically ill patients with detrimental effects in terms of increased morbidity, mortality, costs, and human suffering. Delirium detection and management depends on systematic screening for delirium, which can be challenging to implement in clinical practice.

OBJECTIVES

The aim of this study was to explore how nurses in the intensive care unit perceived the use of Confusion Assessment Method for the Intensive Care Unit (CAM-ICU), the Confusion Assessment Method for the Intensive Care Unit-7 (CAM-ICU-7), and Intensive Care Delirium Screening Checklist (ICDSC) for delirium screening of patients in the intensive care unit.

METHODS

This was a cross-sectional, electronic-based survey of nurses' perceptions of delirium screening with the three different instruments for delirium screening. Nurses were asked to grade their perception of the usability of the three instruments and how well they were perceived to detect delirium and delirium symptom changes on a 1- to 6-point Likert scale. Open questions about perceived advantages and disadvantages of each instrument were analysed using the framework method.

RESULTS

One hundred twenty-seven of 167 invited nurses completed the survey and rated the CAM-ICU-7 as faster and easier than the ICDSC, which was more nuanced and reflected changes in the patient's delirium better. Despite being rated as the fastest, easiest, and most used, the CAM-ICU provided less information and was considered inferior to the CAM-ICU-7 and ICDSC. Using familiar instruments made delirium screening easier, but being able to grade and nuance the delirium assessment was experienced as important for clinical practice.

CONCLUSIONS

Both the ICDSC and the CAM-ICU-7 were perceived well suited for detection of delirium and reflected changes in delirium intensity. The CAM-ICU was rated as fast and easy but inferior in its ability to grade and nuance the assessment of delirium. Emphasis on clinical meaningfulness and continued education in delirium screening are necessary for adherence to delirium management guidelines.

Delirium and subsyndromal delirium in the intensive care unit: In-hospital outcomes and prognosis at discharge

BACKGROUND AND OBJECTIVE

The characteristics and outcomes of patients with subsyndromal delirium (SSD) at hospitalization are still under discussion. The objectives were to describe the incidence of delirium and SSD in the intensive care unit (ICU), to analyze the association with risk factors and to explore outcomes of delirium and SSD at hospitalization and three months after discharge.

PATIENTS AND METHODS

A prospective study, with telephone follow-up three months after discharge. The study included 270 patients over one year. Delirium and SSD were assessed with the CAM-ICU.

RESULTS

22.96% developed delirium and 17.03% SSD. The main risk factors associated with the development of delirium were cognitive impairment (P=.000), age ≥75years (P=.019), neurological admission (P=.003), shock (P=.043), bedsores (P=.010), polypharmacy (P=.017), ARM (P=.001) and fast (P=.028), and with the development of SSD were low schooling (P=.014), Charlson >5 (P=.028), AIVD <8 (P=.001), enteral feeding (P=.000) and non-cardiovascular admission (P=.019). Overall mortality was 6% in the group without delirium (reference), 8% in SSD (P=.516) and 30% in delirium (P=.000). Median ICU length of stay was 2 (IQR, 1-2) days in the group without delirium, 3 (IQR, 2-4) days in SSD (P=.0001), and 3 (IQR, 2-7) days in delirium group (P=.0001). Three months after discharge, instrumental ADL were preserved in 50% of the group without delirium, 30% of SSD (P=.026) and 26% of delirium (P=.005).

CONCLUSIONS

The SSD group presented an intermediate prognosis between no delirium and delirium groups. It is advisable to promote its diagnosis for better risk classification.

Subsyndromal Delirium in Critically Ill Patients-Cognitive and Functional Long-Term Outcomes

Subsyndromal delirium (SSD) in the Intensive Care Unit (ICU) is associated with an increased morbidity with unknown post-discharge functional and cognitive outcomes. We performed a prospective multicenter study to analyze the mental status of patients during their first 72 h after ICU admission and its trajectory, with follow-ups at 3 and 6 months after hospital discharge. Amongst the 106 included patients, SSD occurred in 24.5% (n = 26) and was associated with the duration of mechanical ventilation (p = 0.003) and the length of the ICU stay (p = 0.002). After the initial 72 h, most of the SSD patients (30.8%) improved and no longer had SSD; 19.2% continued to experience SSD and one patient (3.8%) progressed to delirium. The post-hospital discharge survival rate for the SSD patients was 100% at 3 months and 87.5% at 6 months. At admission, 96.2% of the SSD patients were fully independent in daily living activities, 66.7% at 3-month follow-up, and 100% at 6-month follow-up. Most SSD patients demonstrated a cognitive decline from admission to 3-month follow-up and improved at 6 months (IQCODE-SF: admission 3.13, p < 0.001; 3 months 3.41, p = 0.019; 6 months 3.19, p = 0.194). We concluded that early SSD is associated with worse outcomes, mainly a transitory cognitive decline after hospital discharge at 3 months, with an improvement at 6 months. This highlights the need to prevent and identify this condition during ICU stays.

Incidence of Delirium in Critically Ill Patients With and Without COVID-19

BACKGROUND

It is known that patients with COVID-19 are at high risk of developing delirium. The aim of the study was to compare the incidence of delirium between critically ill patients with and without a diagnosis of COVID-19.

METHODS

This is a retrospective study conducted in a southern Brazilian hospital from March 2020 to January 2021. Patients were divided into two groups: the COVID-19 group consisted of patients with a diagnosis of COVID-19 confirmed by reverse transcription-polymerase chain reaction (RT-PCR) or serological tests who were admitted to specific ICUs. The non-COVID-19 group consisted of patients with other surgical and medical diagnoses who were admitted to non-COVID ICUs. All patients were evaluated daily using the Intensive Care Delirium Screening Checklist (ICDSC). The two cohorts were compared in terms of the diagnosis of delirium.

RESULTS

Of the 649 patients who remained more than 48 h in the ICU, 523 were eligible for the study (COVID-19 group: 292, non-COVID-19 group: 231). There were 119 (22.7%) patients who had at least one episode of delirium, including 96 (32.9%) in the COVID-19 group and 23 (10.0%) in the non-COVID-19 group (odds ratio [OR] 4.42; 95% confidence interval [CI], 2.69 to 7.26; p < 0.001). Among patients mechanically ventilated for two days or more, the incidence of delirium did not differ between groups (COVID-19: 89/211, 42.1% vs non-COVID-19: 19/47, 40.4%; p  =  0.82). Logistic regression showed that the duration of mechanical ventilation was the only independent factor associated with delirium (p  =  0.001).

CONCLUSION

COVID-19 can be associated with a higher incidence of delirium among critically ill patients, but there was no difference in this incidence between groups when mechanical ventilation lasted two days or more.

MRI and the Critical Care Patient: Clinical, Operational, and Financial Challenges

Neuroimaging in conjunction with a neurologic examination has become a valuable resource for today's intensive care unit (ICU) physicians. Imaging provides critical information during the assessment and ongoing neuromonitoring of patients for toxic-metabolic or structural injury of the brain. A patient's condition can change rapidly, and interventions may require imaging. When making this determination, the benefit must be weighed against possible risks associated with intrahospital transport. The patient's condition is assessed to decide if they are stable enough to leave the ICU for an extended period. Intrahospital transport risks include adverse events related to the physical nature of the transport, the change in the environment, or relocating equipment used to monitor the patient. Adverse events can be categorized as minor (e.g., clinical decompensation) or major (e.g., requiring immediate intervention) and may occur in preparation or during transport. Regardless of the type of event experienced, any intervention during transport impacts the patient and may lead to delayed treatment and disruption of critical care. This review summarizes the commentary on the current literature on the associated risks and provides insight into the costs as well as provider experiences. Approximately, one-third of patients who are transported from the ICU to an imaging suite may experience an adverse event. This creates an additional risk for extending a patient's stay in the ICU. The delay in obtaining imaging can negatively impact the patient's treatment plan and affect long-term outcomes as increased disability or mortality. Disruption of ICU therapy can decrease respiratory function after the patient returns from transport. Because of the complex care team needed for patient transport, the staff time alone can cost $200 or more. New technologies and advancements are needed to reduce patient risk and improve safety.

Incidence Rate and Factors Associated with Delirium and Subsyndromal Delirium in Patients with COVID-19 in an Intensive Care Unit

BACKGROUND

Delirium subsyndrome (SSD) and delirium (DL) are known complications in the intensive care unit (ICU) and are associated with worse clinical outcomes. The aim of this study was to screen for SSD and DL in individuals with COVID-19 admitted to the ICU and to study the associated factors and clinical outcomes.

METHOD

An observational, longitudinal study was conducted in the reference ICU for COVID-19. All admitted individuals with COVID-19 were screened for SSD and DL during their ICU stay using the Intensive Care Delirium Screening Checklist (ICDSC). Individuals with SSD and/or DL were compared to those without SSD and/or DL.

RESULTS

Ninety-three patients were evaluated, of which 46.7% had SSD and/or DL. The incidence rate was 4.17 cases/100 person-days. Individuals with SSD and/or DL had higher severity of illness on admission to the ICU, as measured by the APACHE II score (median 16 versus 8 points, p < 0.001). SSD and/or DL were associated with longer ICU and hospital stays (median 19 versus 6 days, p < 0.001 and median 22 versus 7 days, p < 0.001, respectively).

CONCLUSION

Individuals with SSD and/or DL had greater disease severity and longer ICU and hospital stays when compared to those without SSD and/or DL. This reinforces the importance of screening for consciousness disorders in the ICU.

Frequency and Risk Factors of Subsyndromal Delirium in the Intensive Care Units: A Prospective Cohort Study

Background

Subsyndromal delirium (SSD) is a common neuropsychiatric disorder among the intensive care units (ICU) patients. SSD is characterized by the presence of delirium symptoms but it does not meet the diagnostic criteria of delirium, resulting in poor patient prognosis.

Objective

The aim of this study was to explore the prevalence and risk factors for SSD among adult patients admitted to the ICU of XXX hospital in Southwest China.

Methods

The study participants comprised 309 patients referred to the ICU in XXX hospital between 10th August 2021 and 5th June 2022. Demographic information, medical history, and other patient information were recorded. ICDSC assessment, physical examination and laboratory tests were performed on enrolled patients. Cognitive evaluation was conducted using the MMSE method.

Results

The results showed that out the 309 patients, 99 had possible SSD (prevalence of 32.0%), with 55 SSD1 cases (ICDSC score of 1, 17.8% prevalence), 29 SSD2 cases (ICDSC score of 2, 9.4% prevalence) and 15 SSD3 cases (ICDSC score of 3, 4.9% prevalence). Previous history of mental illness (OR, 3.741; 95% CI, 1.136-12.324; P <0.05), auxiliary ventilation (OR, 3.364; 95% CI, 1.448-7.813; P <0.01), hemodialysis (OR, 11.369; 95% CI, 1.245-103.840; P <0.05), MMSE score (OR, 0.845; 95% CI, 0.789-0.904; P <0.001) and a temperature ≥ 37.5 °C (OR, 3.686; 95% CI, 1.404-9.732; P <0.01) were independent risk factors for occurrence of SSD among ICU patients.

Conclusion

Approximately one-third of the patients in the intensive care unit had high risk of SSD. Nursing staff should pay attention to management of the high-risk patients to prevent SSD from progressing delirium to improve patient prognosis.

Impact of Subsyndromal Delirium Occurrence and Its Trajectory during ICU Stay

Despite recent advances in the field, the association between subsyndromal delirium (SSD) in the ICU and poor outcomes is not entirely clear. We performed a retrospective multicentric observational study analyzing mental status during the first 72 h of ICU stay. Of the 681 patients included, SSD occurred in 22.7%. Considering the worst cognitive assessment during the first 72 h, 233 (34%) patients had normal mental status, 124 (18%) patients had SSD and 324 (48%) patients had delirium or coma. SSD was not independently associated with an increased risk of death when compared with normal mental status (OR 95%IC 1.0 vs. 1.35 [0.73−1.49], p = 0.340), but was associated with a longer ICU LOS (7.0 (4−12) vs. 4 (3−8) days, p < 0.001). SSD patients who deteriorated to delirium or coma (21%) had a longer ICU LOS in comparison with those who improved or maintained mental status (8 (5−11) vs. 6 (4−8) days, p = 0.025), but did not have an increase in mortality. The main factors associated with the progression from SSD to delirium or coma were the use of mechanical ventilation, the use of intravenous benzodiazepines and a baseline APACHE II score > 23 points. Our findings support the association of SSD with increased ICU LOS, but not with ICU mortality. Monitoring the trajectory of SSD early at ICU admission can help to identify patients with increased risk of conversion from SSD to delirium or coma.

Nurses' assessment of subsyndromal delirium and barriers to assessment: A cross-sectional survey in the intensive care unit

AIMS

The aims of the study are to investigate the current status of nurses' assessment of subsyndromal delirium (SSD) in the intensive care unit (ICU) and explore possible barriers to assessment.

BACKGROUND

SSD is a dynamic, recognizable disorder commonly seen in the ICU that can lead to poor patient outcomes. Timely recognition and management can prevent its progression.

METHODS

A cross-sectional survey design was used to collect data from ICU registered nurses in southwest China. The online survey containing an analysis of the current status of SSD assessment and barriers was completed by 237 nurses.

RESULTS

A total of 51.5% of nurses chose to assess SSD using an assessment tool, the most commonly used being the Confusion Assessment Method for the Intensive Care Unit; the frequency of assessment was mostly once a day (66, 41.0%) and often at shift change (178, 87.3%). There were statistically significant differences in the barrier factor scores by assessment frequency, assessment method, status of training in SSD, ability of SSD-related knowledge to meet clinical needs and willingness to receive SSD training.

CONCLUSION

Our study confirms that the current state of assessment of SSD in the ICU is unsatisfactory, with nurses' lack of assessment knowledge and skills, poor organization and management, and the complexity of patients' conditions being barriers.

IMPLICATIONS FOR NURSING MANAGEMENT

Nursing managers should systematically conduct training programmes on effective SSD assessment knowledge and skills, incorporate SSD assessment into the daily workflow, have standardized assessment tools, develop standardized processes and assign dedicated staff to monitor, audit and provide feedback on SSD assessments.

Risk factors for postoperative delirium on oxygen delivery-guided perfusion

Background

Studies have demonstrated the efficacy of oxygen delivery-guided perfusion (ODGP) in preventing postoperative acute kidney injury, but the benefit of ODGP for delirium has not been confirmed. We retrospectively investigated the risk factors for postoperative delirium in patients who underwent ODGP (with oxygen delivery index [DO2i] > 300 mL/min/m2).

Methods

Consecutive patients who underwent on-pump cardiovascular surgery with ODGP from January 2018 to December 2020 were retrospectively analyzed. In addition to examining patients’ DO2i during cardiopulmonary bypass (CPB), we quantified the two primary DO2 components-hematocrit (Hct) and pump flow. Delirium was defined based on the Intensive Care Delirium Screening Checklist (ICDSC). Patients were divided into three groups: no delirium (ICDSC score = 0), subsyndromal delirium (ICDSC score = 1–3), and clinical delirium (ICDSC score ≥ 4).

Results

Multivariate analysis identified only the number of red blood cell (RBC) units transfused, intubation time, and the cumulative time below the Hct threshold of 25% as predictive factors of postoperative delirium. Although patients with higher ICDSC scores had greater hemodilution during CPB, ODGP resulted in a higher pump flow, and DO2i was maintained above 300 mL/min/m2, with no significant difference between the three groups.

Conclusions

A low Hct level during CPB with ODGP, the number of RBC units transfused, and intubation time were associated with postoperative delirium. Further investigations are needed to determine the ability of ODGP to prevent low Hct during CPB.

Sedation, analgesia, and delirium management in Portugal: a survey and point prevalence study

OBJECTIVE

To establish current Portuguese critical care practices regarding analgesia, sedation, and delirium based on a comparison between the activities reported and daily clinical practice.

METHODS

A national survey was conducted among physicians invited to report their practice toward analgesia, sedation, and delirium in intensive care units. A point prevalence study was performed to analyze daily practices.

RESULTS

A total of 117 physicians answered the survey, and 192 patients were included in the point prevalence study. Survey and point prevalence studies reflect a high sedation assessment (92%; 88.5%), with the Richmond Agitated Sedation Scale being the most reported and used scale (41.7%; 58.2%) and propofol being the most reported and used medication (91.4%; 58.6%). Midazolam prescribing was reported by 68.4% of responders, but a point prevalence study revealed a use of 27.6%.Although 46.4% of responders reported oversedation, this was actually documented in 32% of the patients. The survey reports the daily assessment of pain (92%) using standardized scales (71%). The same was identified in the point prevalence study, with 91.1% of analgesia assessment mainly with the Behavioral Pain Scale. In the survey, opioids were reported as the first analgesic. In clinical practice, acetaminophen was the first option (34.6%), followed by opioids. Delirium assessment was reported by 70% of physicians but was performed in less than 10% of the patients.

CONCLUSION

The results from the survey did not accurately reflect the common practices in Portuguese intensive care units, as reported in the point prevalence study. Efforts should be made specifically to avoid oversedation and to promote delirium assessment.

Delirium in critical illness: clinical manifestations, outcomes, and management

Delirium is the most common manifestation of brain dysfunction in critically ill patients. In the intensive care unit (ICU), duration of delirium is independently predictive of excess death, length of stay, cost of care, and acquired dementia. There are numerous neurotransmitter/functional and/or injury-causing hypotheses rather than a unifying mechanism for delirium. Without using a validated delirium instrument, delirium can be misdiagnosed (under, but also overdiagnosed and trivialized), supporting the recommendation to use a monitoring instrument routinely. The best-validated ICU bedside instruments are CAM-ICU and ICDSC, both of which also detect subsyndromal delirium. Both tools have some inherent limitations in the neurologically injured patients, yet still provide valuable information about delirium once the sequelae of the primary injury settle into a new post-injury baseline. Now it is known that antipsychotics and other psychoactive medications do not reliably improve brain function in critically ill delirious patients. ICU teams should systematically screen for predisposing and precipitating factors. These include exacerbations of cardiac/respiratory failure or sepsis, metabolic disturbances (hypoglycemia, dysnatremia, uremia and ammonemia) receipt of psychoactive medications, and sensory deprivation through prolonged immobilization, uncorrected vision and hearing deficits, poor sleep hygiene, and isolation from loved ones so common during COVID-19 pandemic. The ABCDEF (A2F) bundle is a means to facilitate implementation of the 2018 Pain, Agitation/Sedation, Delirium, Immobility, and Sleep Disruption in Adult Patients in the ICU (PADIS) Guidelines. In over 25,000 patients across nearly 100 institutions, the A2F bundle has been shown in a dose-response fashion (i.e., greater bundle compliance) to yield improved survival, length of stay, coma and delirium duration, cost, and less ICU bounce-backs and discharge to nursing homes.

Phenotypes and subphenotypes of delirium: a review of current categorisations and suggestions for progression

Delirium is a clinical syndrome occurring in heterogeneous patient populations. It affects 45-87% of critical care patients and is often associated with adverse outcomes including acquired dementia, institutionalisation, and death. Despite an exponential increase in delirium research in recent years, the pathophysiological mechanisms resulting in the clinical presentation of delirium are still hypotheses. Efforts have been made to categorise the delirium spectrum into clinically meaningful subgroups (subphenotypes), using psychomotor subtypes such as hypoactive, hyperactive, and mixed, for example, and also inflammatory and non-inflammatory delirium. Delirium remains, however, a constellation of symptoms resulting from a variety of risk factors and precipitants with currently no successful targeted pharmacological treatment. Identifying specific clinical and biological subphenotypes will greatly improve understanding of the relationship between the clinical symptoms and the putative pathways and thus risk factors, precipitants, natural history, and biological mechanism. This will facilitate risk factor mitigation, identification of potential methods for interventional studies, and informed patient and family counselling. Here, we review evidence to date and propose a framework to identify subphenotypes. Endotype identification may be done by clustering symptoms with their biological mechanism, which will facilitate research of targeted treatments. In order to achieve identification of delirium subphenotypes, the following steps must be taken: (1) robust records of symptoms must be kept at a clinical level. (2) Global collaboration must facilitate large, heterogeneous research cohorts. (3) Patients must be clustered for identification, validation, and mapping of subphenotype stability.

Long-Term Outcomes in ICU Patients with Delirium: A Population-based Cohort Study

Rationale: Delirium is common in the ICU and portends worse ICU and hospital outcomes. The effect of delirium in the ICU on post-hospital discharge mortality and health resource use is less well known. Objectives: To estimate mortality and health resource use 2.5 years after hospital discharge in critically ill patients admitted to the ICU. Methods: This was a population-based, propensity score-matched, retrospective cohort study of adult patients admitted to 1 of 14 medical-surgical ICUs from January 1, 2014, to June 30, 2016. Delirium was measured by using the 8-point Intensive Care Delirium Screening Checklist. The primary outcome was mortality. The secondary outcome was a composite measure of subsequent emergency department visits, hospital readmission, or mortality. Measurements and Main Results: There were 5,936 propensity score-matched patients with and without a history of incident delirium who survived to hospital discharge. Delirium was associated with increased mortality 0-30 days after hospital discharge (hazard ratio, 1.44 [95% confidence interval, 1.08-1.92]). There was no significant difference in mortality more than 30 days after hospital discharge (delirium: 3.9%, no delirium: 2.6%). There was a persistent increased risk of emergency department visits, hospital readmissions, or mortality after hospital discharge (hazard ratio, 1.12 [95% confidence interval, 1.07-1.17]) throughout the study period. Conclusions: ICU delirium is associated with increased mortality 0-30 days after hospital discharge.

Risk factors for postoperative delirium and subsyndromal delirium in older patients in the surgical ward: A prospective observational study

Postoperative delirium (POD) and subsyndromal delirium (SSD) among older patients is a common, serious condition associated with a high incidence of negative outcomes. However, there are few accurate methods for the early detection of POD and SSD in surgical wards. This study aimed to identify risk factors of POD and SSD in older patients who were scheduled for surgery in a surgical ward. This was a prospective observational study. Study participants were older than 65 years, underwent urology surgery, and were hospitalized in the surgical ward between April and September 2019. Delirium symptoms were assessed using the Confusion Assessment Method (CAM) on the preoperative day, the day of surgery, and postoperative days 1–3 by the surgical ward nurses. SSD was defined as the presence of one or more CAM criteria and the absence of a diagnosis of delirium based on the CAM algorithm. Personal characteristics, clinical data, cognitive function, physical functions, laboratory test results, medication use, type of surgery and anesthesia, and use of physical restraint and bed sensor were collected from medical records. Multiple logistic regression analyses were conducted to identify the risk factors for both POD and SSD. A total of 101 participants (mean age 74.9 years) were enrolled; 19 (18.8%) developed POD (n = 4) and SSD (n = 15). The use of bed sensors (odds ratio 10.2, p = .001) was identified as a risk factor for both POD and SSD. Our findings suggest that the use of bed sensors might be related to the development of both POD and SSD among older patients in surgical wards.

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.

Prevalence and risk factors of delirium and subsyndromal delirium in older adults

Background

Delirium is a common geriatric problem associated with poor outcomes. Subsyndromal delirium (SSD) is characterized by the presence of certain symptoms of delirium yet, not satisfying the definition of full-blown delirium, defined by categorical elements, and is usually referred to as the presence of one or more symptoms in the confusion assessment method (CAM). This study aimed to investigate the prevalence and risk factors of delirium and SSD in older adults admitted to the hospital. Five hundred eighty-eight elderly (above 65 years) Egyptian patients were recruited from January 2019 to February 2020. After explaining the purpose of the study and assuring the confidentiality of all participants, an informed consent was obtained from the participant or a responsible care giver for those who were not able to give consent. All patients were subjected ‘on admission’ to thorough history taking, clinical examination, and comprehensive geriatric assessment including confusion assessment tools, mini-mental state examination, and functional assessment using Barthel index score.

Results

The current study showed that 19.6% of patients had delirium and 14.1% of patients had SSD with combined prevalence of 33.7%. Most common causes included metabolic, infection, organic brain syndrome, and dehydration. The current study reported significant proportionate relation between cognitive assessment and functional ability, so patients with a score of 23 MMSE had good functional ability, while cognitive assessment using mini-mental score shows inversed relation to delirium and SSD using CAM score.

Conclusion

Delirium is independently associated with adverse short-term and long-term outcomes, including an increase in mortality, length of hospital stay, discharge to an institution, and functional decline on discharge. Subsyndromal delirium (SSD) is characterized by the presence of certain symptoms of delirium, not yet satisfying the definition of full-blown delirium but it can identify patients with early cognitive and functional disabilities, and because of high prevalence of delirium and SSD. Efforts to prevent or early detection may identify patients who warrant clinical attention.

Hyperactive delirium in patients after non-traumatic subarachnoid hemorrhage

PURPOSE

Hyperactive delirium is common after subarachnoid hemorrhage (SAH). We aimed to identify risk factors for delirium and to evaluate its impact on outcome.

METHODS

We collected daily Richmond Agitation Sedation Scale (RASS) and Intensive Care Delirium Screening Checklist (ICDSC) scores in 276 SAH patients. Hyperactive delirium was defined as ICDSC ≥4 when RASS was >0. We investigated risk factors for delirium and its association with 3-month functional outcome using generalized linear models.

RESULTS

Patients were 56 (IQR 47-67) years old and had a Hunt&Hess (H&H) grade of 3 (IQR 1-5). Sixty-five patients (24%) developed hyperactive delirium 6 (IQR 3-16) days after SAH. In multivariable analysis, mechanical ventilation>48 h (adjOR = 4.46; 95%-CI = 1.89-10.56; p = 0.001), the detection of an aneurysm (adjOR = 4.38; 95%-CI = 1.48-12.97; p = 0.008), a lower H&H grade (adjOR = 0.63; 95%-CI = 0.48-0.83; p = 0.001) and a pre-treated psychiatric disorder (adjOR = 3.17; 95%-CI = 1.14-8.83; p = 0.027) were associated with the development of delirium. Overall, delirium was not associated with worse outcome (p = 0.119). Interestingly, patients with delirium more often had a modified Rankin Scale Score (mRS) of 1-3 (77%) compared to an mRS of 0 (14%) or 4-6 (9%).

CONCLUSION

Our data indicate that hyperactive delirium is common after SAH patients and requires a certain degree of brain connectivity based ono the highest prevalence found in SAH patients with intermediate outcomes.

Patients, family members and providers perceive family-administered delirium detection tools in the adult ICU as feasible and of value to patient care and family member coping: a qualitative focus group study

PURPOSE

While studies report on perceptions of family participation in delirium prevention, little is known about the use of family-administered delirium detection tools in the care of critically ill patients. This study sought the perspectives of patients, their family members, and healthcare providers on the use of family-administered delirium detection tools to detect delirium in critically ill patients and barriers and facilitators to using family-administered delirium detection tools in patient care.

METHODS

In this qualitative study, critical care providers (five physicians, six registered nurses) and participants from the Family ICU Delirium Detection Study (seven past patients and family members) took part in four focus groups at one hospital in Calgary, Alberta.

RESULTS

Key themes identified following thematic analysis from 18 participants included: 1) perceptions of acceptability of family-administered delirium detection (e.g., family feels valued, intensive care unit (ICU) care team may not use a family member's results, intensification of work load), 2) considerations regarding feasibility (e.g., insufficient knowledge, healthcare team buy-in), and 3) overarching strategies to support implementation into routine patient care (e.g., value of family-administered delirium detection for patients and families is well understood in the clinical context, regular communication between the family and ICU providers, an electronic version of the tool).

CONCLUSIONS

Patients, family members and healthcare providers who participated in the focus groups perceived family participation in delirium detection and the use of family-administered delirium detection tools at the bedside as feasible and of value to patient care and family member coping.

TRIAL REGISTRATION

www.ClinicalTrials.gov (NCT03379129); registered 15 December 2017.

Subsyndromal Delirium in Cardiac Surgery Patients: Risk Factors and Outcomes of the Different Trajectories

BACKGROUND

Subsyndromal delirium (SSD), a subthreshold form of delirium, is related to longer length of stay and increased mortality rates among older adults. Risk factors and outcomes of SSD in cardiac surgery patients are not fully understood.

OBJECTIVE

The aim of this study was to assess and describe the characteristics and outcomes related to trajectories of SSD and delirium in cardiac surgery patients.

METHODS

In this secondary analysis of a retrospective case-control (1:1) cohort study, SSD was defined as a score between 1 and 3 on the Intensive Care Delirium Screening Checklist paired with an absence of diagnosis of delirium on the day of assessment. Potential risk factors (eg, age) and outcomes (eg, mortality) were identified from existing literature. Patients were grouped into 4 trajectories: (1) without SSD or delirium, (2) SSD only, (3) both, and (4) delirium only. These trajectories were contrasted using analysis of variance or χ2 test.

RESULTS

Among the cohort of 346 patients, 110 patients did not present with SSD or delirium, 62 presented with only SSD, 69 presented with both, and 105 presented with only delirium. In comparison with patients without SSD or delirium, patients with SSD presented preoperative risk factors known for delirium (ie, older age, higher European System for Cardiac Operative Risk Evaluation II) but underwent less complicated surgical procedures, received fewer transfusions postoperatively, and had a lower positive fluid balance postoperatively than patients who presented with delirium. Patients with both SSD and delirium had worse outcomes in comparison with those with delirium only.

CONCLUSION

This study stresses the importance for healthcare professionals to identify SSD and prevent its progression to delirium.

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.

Delirium in the acute hospital setting: the role of psychiatry

In this overview we discuss the role of psychiatry in managing delirium in acute hospital admissions. We briefly discuss the role psychiatry can offer in four main domains: (a) assessment; (b) management; (c) recovery; and (d) paradigm, education and research. In the assessment section we discuss accurately detecting delirium in the context of comorbid mixed neuropsychiatric syndromes, including depression and dementia, and the clinical importance of delirium subtyping. The management section briefly outlines pharmacological and non-pharmacological approaches to delirium and their evidence-based rationale. The recovery section focuses on the effect delirium can have on cognitive decline, mental health and long-term health, including functional outcome and need for institutional care after hospital discharge. Finally, we outline the role of psychiatry in delirium research and education. We hope that this article will encourage clinicians to reflect on their current practice and consider holistic and evidence-based care for this vulnerable population in the acute hospital setting.

Protocol for the Prognosticating Delirium Recovery Outcomes Using Wakefulness and Sleep Electroencephalography (P-DROWS-E) study: a prospective observational study of delirium in elderly cardiac surgical patients

INTRODUCTION

Delirium is a potentially preventable disorder characterised by acute disturbances in attention and cognition with fluctuating severity. Postoperative delirium is associated with prolonged intensive care unit and hospital stay, cognitive decline and mortality. The development of biomarkers for tracking delirium could potentially aid in the early detection, mitigation and assessment of response to interventions. Because sleep disruption has been posited as a contributor to the development of this syndrome, expression of abnormal electroencephalography (EEG) patterns during sleep and wakefulness may be informative. Here we hypothesise that abnormal EEG patterns of sleep and wakefulness may serve as predictive and diagnostic markers for postoperative delirium. Such abnormal EEG patterns would mechanistically link disrupted thalamocortical connectivity to this important clinical syndrome.

METHODS AND ANALYSIS

P-DROWS-E (Prognosticating Delirium Recovery Outcomes Using Wakefulness and Sleep Electroencephalography) is a 220-patient prospective observational study. Patient eligibility criteria include those who are English-speaking, age 60 years or older and undergoing elective cardiac surgery requiring cardiopulmonary bypass. EEG acquisition will occur 1-2 nights preoperatively, intraoperatively, and up to 7 days postoperatively. Concurrent with EEG recordings, two times per day postoperative Confusion Assessment Method (CAM) evaluations will quantify the presence and severity of delirium. EEG slow wave activity, sleep spindle density and peak frequency of the posterior dominant rhythm will be quantified. Linear mixed-effects models will be used to evaluate the relationships between delirium severity/duration and EEG measures as a function of time.

ETHICS AND DISSEMINATION

P-DROWS-E is approved by the ethics board at Washington University in St. Louis. Recruitment began in October 2018. Dissemination plans include presentations at scientific conferences, scientific publications and mass media.

TRIAL REGISTRATION NUMBER

NCT03291626.

The CAM-ICU-7 and ICDSC as measures of delirium severity in critically ill adult patients

Background

In clinical practice, a dichotomous approach to delirium identification may no longer be relevant when existing delirium screening tools measure a range of scores. The objective of this study was to compare the Confusion Assessment Method for the Intensive Care Unit 7-item (CAM-ICU-7) and the Intensive Care Delirium Screening Checklist (ICDSC) as measures of the spectrum of delirium severity in critically ill adult patients.

Methods

In this cross-sectional study, 218 patients underwent 641 paired assessments by bedside nurses (ICDSC, as per usual care) and trained research assistants (CAM-ICU-7). Correlation between the CAM-ICU-7 and ICDSC scores was evaluated. Logistic regression was used to explore associations between CAM-ICU-7 or ICDSC score and length of ICU stay and mechanical ventilation (receipt, ≥96 hours).

Results

Delirium prevalence evaluated by the CAM-ICU-7 and ICDSC were 46.3% (95% CI:39.7–53.0) and 34.4% (95% CI:28.3–41.0). Prevalence of less than clinical threshold symptoms of delirium evaluated by the CAM-ICU-7 (score: 1–2) and ICDSC (score: 1–3) were 30.3% (95%CI:24.5–36.7) and 50.9% (95%CI:44.3–57.6). The CAM-ICU-7 and ICDSC had significant positive correlation (0.58, p<0.001). Agreement between the tools as measures of delirium was moderate (kappa = 0.51) and as measures of less than clinical threshold symptoms of delirium was fair (kappa = 0.21). Less than clinical threshold symptoms of delirium identified by the ICDSC, not CAM-ICU-7, were associated with prolonged length of ICU stay (≥7 days) in patients <65 years of age [Odds Ratio (OR) 9.2, 95% CI:2.5–34.0] and mechanical ventilation (receipt: OR 2.8, 95% CI:1.3–6.4; ≥96 hours: OR 6.6, 95% CI:1.9–22.9), when compared to patients with no delirium.

Conclusions

The CAM-ICU-7 and ICDSC are measures of the spectrum of delirium severity that are closely correlated. Less than clinical threshold symptoms of delirium measure by the ICDSC is a better predictor of outcomes, when compared with the CAM-ICU-7.

Delirium

Delirium, a syndrome characterized by an acute change in attention, awareness and cognition, is caused by a medical condition that cannot be better explained by a pre-existing neurocognitive disorder. Multiple predisposing factors (for example, pre-existing cognitive impairment) and precipitating factors (for example, urinary tract infection) for delirium have been described, with most patients having both types. Because multiple factors are implicated in the aetiology of delirium, there are likely several neurobiological processes that contribute to delirium pathogenesis, including neuroinflammation, brain vascular dysfunction, altered brain metabolism, neurotransmitter imbalance and impaired neuronal network connectivity. The Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5) is the most commonly used diagnostic system upon which a reference standard diagnosis is made, although many other delirium screening tools have been developed given the impracticality of using the DSM-5 in many settings. Pharmacological treatments for delirium (such as antipsychotic drugs) are not effective, reflecting substantial gaps in our understanding of its pathophysiology. Currently, the best management strategies are multidomain interventions that focus on treating precipitating conditions, medication review, managing distress, mitigating complications and maintaining engagement to environmental issues. The effective implementation of delirium detection, treatment and prevention strategies remains a major challenge for health-care organizations globally.

Influence of Sedation Level and Ventilation Status on the Diagnostic Validity of Delirium Screening Tools in the ICU-An International, Prospective, Bi-Center Observational Study (IDeAS)

Background and objectives: The use of delirium screening instruments (DSIs) is recommended in critical care practice for a timely detection of delirium. We hypothesize that the patient-related factors “level of sedation” and “mechanical ventilation” impact test validity of DSIs. Materials and Methods: This is a prospective, bi-center observational study (clinicaltrials.gov: NCT01720914). Critically ill patients were screened for delirium daily for up to seven days after enrollment using the Nursing Delirium Screening Scale (Nu-DESC), Intensive Care Delirium Screening Checklist (ICDSC), and Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). Reference standard for delirium diagnosis was the neuropsychiatric examination using the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR). Immediately before delirium assessment, ventilation status and sedation levels were documented. Results: 160 patients were enrolled and 151 patients went into final analysis. Delirium incidence was 23.2%. Nu-DESC showed a sensitivity and specificity of 88.5%, a positive predictive value (PPV) of 71.9%, and a negative predictive value (NPV) of 95.8%. ICDSC had a sensitivity of 62.5%, a specificity of 92.4%, a PPV of 71.4%, and a NPV of 89.0%. CAM-ICU showed a sensitivity of 75.0%, a specificity of 94.7%, a PPV of 85.7%, and a NPV of 90.0%. For Nu-DESC and ICDSC, test validity was significantly better for non-sedated patients (Richmond Agitation Sedation Scale (RASS) 0/−1), whereas test validity for CAM-ICU in a severity scale version showed no significant differences for different sedation levels. No DSI showed a significant difference in test validity between noninvasively and invasively ventilated patients. Conclusions: Test validities of DSIs were comparable to previous studies. The observational scores ICDSC and Nu-DESC showed a significantly better performance in awake and drowsy patients (RASS 0/−1) when compared with other sedation levels. Physicians should refrain from sedation whenever possible to avoid suboptimal performance of DSIs.

What factors predict length of stay in the intensive care unit? Systematic review and meta-analysis

PURPOSE

Studies have shown that a small percentage of ICU patients have prolonged length of stay (LoS) and account for a large proportion of resource use. Therefore, the identification of prolonged stay patients can improve unit efficiency. In this study, we performed a systematic review and meta-analysis to understand the risk factors of ICU LoS.

MATERIALS AND METHODS

We searched MEDLINE, Embase and Scopus databases from inception to November 2018. The searching process focused on papers presenting risk factors of ICU LoS. A meta-analysis was performed for studies reporting appropriate statistics.

RESULTS

From 6906 citations, 113 met the eligibility criteria and were reviewed. A meta-analysis was performed for six factors from 28 papers and concluded that patients with mechanical ventilation, hypomagnesemia, delirium, and malnutrition tend to have longer stay, and that age and gender were not significant factors.

CONCLUSIONS

This work suggested a list of risk factors that should be considered in prediction models for ICU LoS, as follows: severity scores, mechanical ventilation, hypomagnesemia, delirium, malnutrition, infection, trauma, red blood cells, and PaO2:FiO2. Our findings can be used by prediction models to improve their predictive capacity of prolonged stay patients, assisting in resource allocation, quality improvement actions, and benchmarking analysis.

The association of delirium severity with patient and health system outcomes in hospitalised patients: a systematic review

BACKGROUND

delirium is an acute state of confusion that affects >20% of hospitalised patients. Recent literature indicates that more severe delirium may lead to worse patient outcomes and health system outcomes, such as increased mortality, cognitive impairment and length of stay (LOS).

METHODS

using systematic review methodology, we summarised associations between delirium severity and patient or health system outcomes in hospitalised adults. We searched MEDLINE, EMBASE, PsycINFO, CINAHL and Scopus databases with no restrictions, from inception to 25 October 2018. We included original observational research conducted in hospitalised adults that reported on associations between delirium severity and patient or health system outcomes. Quality of included articles was assessed using the Newcastle-Ottawa Scale. The level of evidence was quantified based on the consistency of findings and quality of studies reporting on each outcome.

RESULTS

we included 20 articles evaluating associations that reported: mortality (n = 11), cognitive ability (n = 3), functional ability (n = 3), patient distress (n = 1), quality of life (n = 1), hospital LOS (n = 4), intensive care unit (ICU) LOS (n = 2) and discharge home (n = 2). There was strong-level evidence that delirium severity was associated with increased ICU LOS and a lower proportion of patients discharged home. There was inconclusive evidence for associations between delirium severity and mortality, hospital LOS, functional ability, cognitive ability, patient distress and quality of life.

CONCLUSION

delirium severity is associated with increased ICU LOS and a lower proportion of patients discharged home. Delirium severity may be a useful adjunct to existing delirium screening to determine the burden to health care system resources.

The role of suvorexant in the prevention of delirium during acute hospitalization: A systematic review

PURPOSE

To assess the efficacy and safety of suvorexant for the prevention of delirium during acute hospitalization.

MATERIALS AND METHODS

Pubmed (1946 to December 2019) and Embase (1947 to December 2019) were queried using the search term combination: delirium, confusion, cognitive defect, encephalopathy, critically ill patient, critical illness, or hospitalization and suvorexant or orexin receptor antagonist. Studies analyzed for relevance evaluated clinical outcomes of patients treated with suvorexant for prevention of delirium. Studies appropriate to the objective were evaluated, including two randomized controlled trials and four retrospective studies.

RESULTS

In acutely hospitalized patients, treatment with suvorexant 15 to 20 mg alone or in combination with ramelteon resulted in a reduction in development of delirium, time until delirium onset, and length of hospital stay. When assessed, suvorexant was well tolerated and adverse effects were no worse than placebo.

CONCLUSION

Based on the reviewed literature, suvorexant has shown positive outcomes in the prevention of delirium during an acute hospitalization. Larger trials comparing the efficacy of suvorexant to other sleep modulating options are necessary to further delineate its role for the prevention of delirium.

Sepsis Associated Delirium

Sepsis is a potentially life-threatening condition caused by a systemic dysregulated host response to infection. The brain is particularly susceptible to the effects of sepsis with clinical manifestations ranging from mild confusion to a deep comatose state. Sepsis-associated delirium (SAD) is a cerebral manifestation commonly occurring in patients with sepsis and is thought to occur due to a combination of neuroinflammation and disturbances in cerebral perfusion, the blood brain barrier (BBB) and neurotransmission. The neurological impairment associated with SAD can persist for months or even longer, after the initial septic episode has subsided which may impair the rehabilitation potential of sepsis survivors. Early identification and treatment of the underlying sepsis is key in the management of SAD as once present it can be difficult to control. Through the regular use of validated screening tools for delirium, cases of SAD can be identified early; this allows potentially aggravating factors to be addressed promptly. The usefulness of biomarkers, neuroimaging and electroencephalopathy (EEG) in the diagnosis of SAD remains controversial. The Society of Critical Care Medicine (SCCM) guidelines advise against the use of medications to treat delirium unless distressing symptoms are present or it is hindering the patient’s ability to wean from organ support.