Epidemiology and risk factors for delirium across hospital settings

Machine learning with clinical and intraoperative biosignal data for predicting postoperative delirium after cardiac surgery

Early identification of patients at high risk of delirium is crucial for its prevention. Our study aimed to develop machine learning models to predict delirium after cardiac surgery using intraoperative biosignals and clinical data. We introduced a novel approach to extract relevant features from continuously measured intraoperative biosignals. These features reflect the patient's overall or baseline status, the extent of unfavorable conditions encountered intraoperatively, and beat-to-beat variability within the data. We developed a soft voting ensemble machine learning model using retrospective data from 1,912 patients. The model was then prospectively validated with data from 202 additional patients, achieving a high performance with an area under the receiver operating characteristic curve of 0.887 and an accuracy of 0.881. According to the SHapley Additive exPlanation method, several intraoperative biosignal features had high feature importance, suggesting that intraoperative patient management plays a crucial role in preventing delirium after cardiac surgery.

Effect of remimazolam versus propofol anesthesia on postoperative delirium in neurovascular surgery: study protocol for a randomized controlled, non-inferiority trial

BACKGROUND

Remimazolam is a short-acting benzodiazepine newly approved for the induction and maintenance of general anesthesia. Remimazolam emerges as an ideal drug for the neurosurgical population due to its rapid emergence, enabling early neurological assessment, and its ability to maintain perfusion pressure, which is crucial for preventing cerebral ischemia. However, the use of benzodiazepine has been associated with an increased risk of postoperative delirium (POD). There is currently limited evidence about the relationship between remimazolam-based total intravenous anesthesia (TIVA) and POD.

METHODS

In this double-blind, randomized, non-inferiority trial, we plan to include 696 adult patients with American Society of Anesthesiologists physical status class I to III, undergoing elective neurovascular surgery under general anesthesia. After informed consent, the patients will be randomized to receive either remimazolam or propofol-based TIVA with a 1:1 ratio. The primary outcome is the incidence of POD within 5 days after surgery. Secondary outcomes include subtypes, number of positive assessments and severity of POD, emergence agitation, intraoperative awareness and undesirable patient movement, intraoperative hypotension, and postoperative cognitive function. The data will be analyzed in modified intention to treat.

DISCUSSION

This trial will evaluate the effect of remimazolam on the development of POD compared to propofol anesthesia. The results of this trial will provide evidence regarding the choice of optimal anesthetics to minimize the risk of POD in neurosurgical patients.

TRIAL REGISTRATION

The study protocol was prospectively registered at the Clinical trials ( https://clinicaltrials.gov , NCT06115031, principal investigator: Jiseon Jeong; date of first registration: November 2, 2023, before the recruitment of the first participant.

Multicentre implementation of a quality improvement initiative to reduce delirium in adult intensive care units: An interrupted time series analysis

PURPOSE

The ABCDEF bundle may improve delirium outcomes among intensive care unit (ICU) patients, however population-based studies are lacking. In this study we evaluated effects of a quality improvement initiative based on the ABCDEF bundle in adult ICUs in Alberta, Canada.

MATERIAL AND METHODS

We conducted a pre-post, registry-based clinical trial, analysed using interrupted time series methodology. Outcomes were examined via segmented linear regression using mixed effects models. The main data source was a population-based electronic health record.

RESULTS

44,405 consecutive admissions (38,400 unique patients) admitted to 15 general medical/surgical and/or neurologic adult ICUs between 2014 and 2019 were included. The proportion of delirium days per ICU increased from 30.24% to 35.31% during the pre-intervention period. After intervention implementation it decreased significantly (bimonthly decrease of 0.34%, 95%CI 0.18-0.50%, p < 0.01) from 33.48% (95%CI 29.64-37.31%) in 2017 to 28.74% (95%CI 25.22-32.26%) in 2019. The proportion of sedation days using midazolam demonstrated an immediate decrease of 7.58% (95%CI 4.00-11.16%). There were no significant changes in duration of invasive ventilation, proportion of partial coma days, ICU mortality, or potential adverse events.

CONCLUSIONS

An ABCDEF delirium initiative was implemented on a population-basis within adult ICUs and was successful at reducing the prevalence of delirium.

Effect of remimazolam vs propofol on emergence from general anesthesia in patients undergoing cerebral endovascular procedures: A randomized controlled, non-inferiority trial

STUDY OBJECTIVE

This study aimed to compare the time to emergence from general anesthesia with remimazolam versus propofol in patients undergoing cerebral endovascular procedures.

DESIGN

A prospective, double-blind, randomized controlled, non-inferiority trial.

SETTING

An academic hospital.

PATIENTS

Adult patients scheduled for cerebral endovascular procedures.

INTERVENTIONS

Patients were randomized at a 1:1 ratio to undergo surgery under general anesthesia with remimazolam (0.1 mg kg-1 for induction and 0.3-0.7 mg kg-1 h-1 for maintenance) or propofol (1-1.5 mg kg-1 for induction and 4-10 mg kg-1 h-1 for maintenance).

MEASUREMENTS

The primary outcome was the time to emergence from anesthesia. The non-inferiority margin was -2.55 min in group difference. Major secondary outcomes included hypotension during induction, incidence of postoperative delirium and Modified Rankin Scale (mRs) at 30 days and 90 days after surgery.

MAIN RESULTS

Of the 142 randomized patients, 129 completed the trial. In the modified intention-to-treat analysis, the mean time to emergence from anesthesia was 16.1 [10.4] min in the remimazolam group vs. 19.0 [11.2] min in the propofol group. The group difference was -2.9 min [95% CI -6.5, 0.7] (P = 0.003 for non-inferiority). The remimazolam group had lower rate of hypotension during induction (11.3% vs 25.4%, P = 0.03) and use of vasopressors during surgery (29.6% vs 62.0%, P < 0.001). The two groups did not differ in postoperative delirium and mRs at 30 and 90 days after surgery.

CONCLUSIONS

In patients undergoing cerebral endovascular procedures, remimazolam did not increase the time from anesthesia vs propofol.

The possible clinical utility of the alcohol biomarker phosphatidylethanol for managing suspected alcohol withdrawal in hospitalized patients: A case report

BACKGROUND AND OBJECTIVES

The decision to initiate pharmacotherapy for alcohol withdrawal is typically based on examining self-reported use of alcohol and symptoms of withdrawal. Phosphatidylethanol (PEth) is a biomarker that could aim in clinical decision-making in withdrawal management.

METHODS

This report describes three cases highlighting the potential clinical utility of PEth in caring for individuals at risk for alcohol withdrawal.

RESULTS

Two of the cases received phenobarbital when their PEth showed that the risk of withdrawal was low and one case where PEth could have shown this was needed. The results were only available in a delayed fashion, however, could have been useful in informing clinical care.

DISCUSSION AND CONCLUSION

PEth can be a useful tool if available without delay. PEth can be used to quickly rule out alcohol withdrawal and avoid misdiagnoses and prolonged hospital stays.

SCIENTIFIC SIGNIFICANCE

This is a clinical case study available looking at PEth and withdrawal in hospitalized patients. It proposes that PEth can be used as a way to quickly rule out alcohol withdrawal to avoid misdiagnoses and the possibility of a prolonged hospital stay.

The Validity and Applicability of the Revised Delirium Rating Scale (DRS-R98) for Delirium Severity Assessment in a Critical Care Setting

BACKGROUND

Delirium is a neuropsychiatric syndrome common in critical illness. Worsening delirium severity is associated with poorer clinical outcomes, yet its assessment remains under-reported with most severity assessment tools not validated for critical care. The DRS-R98 is a widely applied and validated tool. The aim of this project is to report the validation and utility of the DRS-R98 in critical illness.

METHODS

This prospective, cohort study was conducted in adults with delirium admitted to a critical care unit and predicted to stay for ≥ 24 h. We excluded patients with severe neurological or communication barriers that would have interfered with the DRS-R98 assessment. Patients were screened using a delirium detection algorithm and the Confusion Assessment Method for the Intensive Care Unit. Eligible patient informations were collected and reported to qualified assessor/s before visiting clinical areas, confirming delirium presence and undertaking DRS- R98 assessments. To assess the tool's construct validity, an intensivist completed the Clinical Global Impression-Scale (CGI-S). To calculate the inter-rater reliability (IRR) a subset of patients were simultaneously evaluated by two assessors.

RESULTS

We assessed 22 patients, 73% were male, with a median age of 65 years (IQR14). The DRS -R98 mean (SD) severity score was 24 (+/-7.7), total scale was 29 (+/18.0), and CGI-S 3.5 (+/11.5). Assessment duration was 90 min (+/-55) and 15 min (+/-5) for record data extraction and clinical assessment respectively. The CGI-S significantly correlated with DRS-R98 severity (r = 0.626) and total (r = 0.628) scales. The DRS-R98 Cronbach's alpha was 0.896 for severity scale and 0.886 for total scale. The inter-rater reliability (IRR) was assessed in six patients and reported an inter-correlation coefficient of 0.505 (p = 0.124) and 0.565 (p = 0.93) for the severity and total scale respectively.

CONCLUSIONS

In critical care, the Delirium Rating Scale R98 had good construct validity, excellent internal consistency, and moderate inter-rater reliability.

Point prevalence and clinical profile of patients with delirium admitted in internal medicine department at tertiary care centre in eastern Nepal: a descriptive cross-sectional study

Introduction

Delirium, marked by acute disturbances in consciousness and cognition, remains underdiagnosed despite its significant impact on morbidity and mortality. This study investigates the point prevalence and clinical profile of delirium in patients at an eastern Nepal tertiary care centre.

Methods

A 1-month descriptive cross-sectional study involved 152 Internal Medicine Department patients at BPKIHS, Dharan. Data, collected through face-to-face interviews and the Confusion Assessment Method (CAM), analyzed demographic details, clinical history, and laboratory findings. Ethical clearance and informed consent were obtained.

Results

Among 152 participants, 13.2% exhibited delirium, with notable risk factors identified. Elderly patients (≥65 years) and those with nasogastric tubes faced higher risks. Significant associations were found with cardiovascular diseases (P=0.002), central nervous system diseases (P=0.015), and alcoholism (P=0.003). Laboratory findings revealed correlations with elevated creatinine, hyperuremia, and abnormal aspartate aminotransferase levels. The study emphasizes key contributors to delirium, providing valuable insights for clinicians in identifying, preventing, and managing delirium in a hospital setting.

Conclusions

This study provides critical insights into delirium prevalence and profiles in Eastern Nepal. Identified risk factors underscore the importance of routine screenings and targeted interventions for at-risk populations. Study limitations, including sample size and single-centre focus, call for further research to validate findings and enhance our understanding of delirium's management across diverse healthcare settings. Overall, the study informs clinical practices and prompts broader exploration of delirium in healthcare contexts.

Incidence of confusional syndrome (delirium) in a Latin American university hospital

BACKGROUND

Little is known about the incidence of delirium and its subtypes in patients admitted to different departments of university hospitals in Latin America.

OBJECTIVE

To determine the incidence of delirium and the frequency of its subtypes, as well as its associated factors, in patients admitted to different departments of a university hospital in Bogotá, Colombia.

METHODS

A cohort of patients over 18 years of age admitted to the internal medicine (IM), geriatrics (GU), general surgery (GSU), orthopaedics (OU) and intensive care unit (ICU) services of a university hospital was followed up between January and June 2018. To detect the presence of delirium, we used the CAM (Confusion Assessment Method) and the CAM-ICU if the patient had decreased communication skills. The delirium subtype was characterised using the RASS (Richmond Agitation and Sedation Scale). Patients were assessed on their admission date and then every two days until discharged from the hospital. Those in whom delirium was identified were referred for specialised intra-institutional interdisciplinary management.

RESULTS

A total of 531 patients admitted during the period were assessed. The overall incidence of delirium was 12% (95% CI, 0.3-14.8). They represented 31.8% of patients in the GU, 15.6% in the ICU, 8.7% in IM, 5.1% in the OU, and 3.9% in the GSU. The most frequent clinical display was the mixed subtype, at 60.9%, followed by the normoactive subtype (34.4%) and the hypoactive subtype (4.7%). The factors most associated with delirium were age (adjusted RR = 1.07; 95% CI, 1.05-1.09), the presence of four or more comorbidities (adjusted RR = 2.04; 95% CI, 1.31-3.20), and being a patient in the ICU (adjusted RR = 2.02; 95% CI, 1.22-3.35).

CONCLUSIONS

The incidence of delirium is heterogeneous in the different departments of the university hospital. The highest incidence occurred in patients that were admitted to the GU. The mixed subtype was the most frequent one, and the main associated factors were age, the presence of four or more comorbidities, and being an ICU patient.

Prevalence of Delirium After Abdominal Surgery and Association With Ketamine: A Retrospective, Propensity-Matched Cohort Study

IMPORTANCE

Delirium is a common postoperative complication for older patients in the ICU. Ketamine, used primarily as an analgesic, has been thought to prevent delirium.

OBJECTIVE

Determine the prevalence and association of delirium with low-dose ketamine use in ICU patients after abdominal surgery.

DESIGN

Single-center, retrospective, propensity-matched cohort study.

SETTING

Eight hospital academic medical center.

PATIENTS

Cohort comprising 1836 patients admitted to the ICU after abdominal surgery between June 23, 2018 and September 1, 2022.

MAIN OUTCOMES AND MEASURES

Propensity score matching (PSM) with a 3:1 ratio between no-ketamine use and ketamine use was performed through a greedy algorithm (caliper of 0.005). Outcomes of interest included: delirium (assessed by Confusion Assessment Method-ICU), mean pain score (Numeric Pain Scale or Critical Care Pain Observation Tool score as available), mean opioid consumption (morphine milligram equivalents), length of stay (d), and mortality.

RESULTS

Prevalence of delirium was 47.71% (95% CI, 45.41-50.03%) in the cohort. Of 1836 patients, 120 (6.54%) used low-dose ketamine infusion. After PSM, the prevalence of delirium was 56.02% (95% CI, 51.05-60.91%) in all abdominal surgery patients. The ketamine group had 41% less odds of delirium (odds ratio [OR] = 0.59; 95% CI, 0.37-0.94; p = 0.026) than patients with no-ketamine use. Patients with ketamine use had higher mean pain scores (3.57 ± 2.86 vs. 2.21 ± 2.09, p < 0.001). In the subgroup analysis, patients in the ketamine-use group 60 years old or younger had 64% less odds of delirium (OR = 0.36; 95% CI, 0.13-0.95; p = 0.039). The mean pain scores were higher in the ketamine group for patients 60 years old or older. There was no significant difference in mortality and opioid consumption.

CONCLUSIONS AND RELEVANCE

Low-dose ketamine infusion was associated with lower prevalence of delirium in ICU patients following abdominal surgery. Prospective studies should further evaluate ketamine use and delirium.

Precision-based approaches to delirium in critical illness: A narrative review

Delirium occurs in critical illness and is associated with poor clinical outcomes, having a longstanding impact on survivors. Understanding the complexity of delirium in critical illness and its deleterious outcome has expanded since early reports. Delirium is a culmination of predisposing and precipitating risk factors that result in a transition to delirium. Known risks range from advanced age, frailty, medication exposure or withdrawal, sedation depth, and sepsis. Because of its multifactorial nature, different clinical phenotypes, and potential neurobiological causes, a precise approach to reducing delirium in critical illness requires a broad understanding of its complexity. Refinement in the categorization of delirium subtypes or phenotypes (i.e., psychomotor classifications) requires attention. Recent advances in the association of clinical phenotypes with clinical outcomes expand our understanding and highlight potentially modifiable targets. Several delirium biomarkers in critical care have been examined, with disrupted functional connectivity being precise in detecting delirium. Recent advances reinforce delirium as an acute, and partially modifiable, brain dysfunction, and place emphasis on the importance of mechanistic pathways including cholinergic activity and glucose metabolism. Pharmacologic agents have been assessed in randomized controlled prevention and treatment trials, with a disappointing lack of efficacy. Antipsychotics remain widely used after "negative" trials, yet may have a role in specific subtypes. However, antipsychotics do not appear to improve clinical outcomes. Alpha-2 agonists perhaps hold greater potential for current use and future investigation. The role of thiamine appears promising, yet requires evidence. Looking forward, clinical pharmacists should prioritize the mitigation of predisposing and precipitating risk factors as able. Future research is needed within individual delirium psychomotor subtypes and clinical phenotypes to identify modifiable targets that hold the potential to improve not only delirium duration and severity, but long-term outcomes including cognitive impairment.

Association between postoperative delirium and adverse outcomes in older surgical patients: A systematic review and meta-analysis

STUDY OBJECTIVE

To assess the incidence of postoperative delirium and its outcomes in older non-cardiac surgical patients.

DESIGN

A systematic review and meta-analysis with multiple databases searched from inception to February 22, 2022.

SETTING

Postoperative assessments.

PATIENTS

Non-cardiac and non-neurological surgical patients aged ≥60 years with and without postoperative delirium. Included studies must report ≥1 postoperative outcome. Studies with a small sample size (N < 100 subjects) were excluded.

MEASUREMENTS

Outcomes comprised the pooled incidence of postoperative delirium and its postoperative outcomes, including mortality, complications, unplanned intensive care unit admissions, length of stay, and non-home discharge. For dichotomous and continuous outcomes, OR and difference in means were computed, respectively, with a 95% CI.

MAIN RESULTS

Fifty-four studies (20,988 patients, 31 elective studies, 23 emergency studies) were included. The pooled incidence of postoperative delirium was 19% (95% CI: 16%, 23%) after elective surgery and 32% (95% CI: 25%, 39%) after emergency surgery. In elective surgery, postoperative delirium was associated with increased mortality at 1-month (OR: 6.60; 95% CI: 1.58, 27.66), 6-month (OR: 5.69; 95% CI: 2.33, 13.88), and 1-year (OR: 2.87; 95% CI: 1.63, 5.06). The odds of postoperative complications, unplanned intensive care unit admissions, prolonged length of hospital stay, and non-home discharge were also higher in delirium cases. In emergency surgery, patients with postoperative delirium had greater odds of mortality at 1-month (OR: 3.56; 95% CI: 1.77, 7.15), 6-month (OR: 2.60; 95% CI: 1.88, 3.61), and 1-year (OR: 2.30; 95% CI: 1.77, 3.00).

CONCLUSIONS

Postoperative delirium was associated with higher odds of mortality, postoperative complications, unplanned intensive care unit admissions, length of hospital stay, and non-home discharge. Prevention and perioperative management of delirium may optimize surgical outcomes.

A Lethal Combination of Delirium and Overcrowding in the Emergency Department

Delirium is a common public health concern that significantly impacts older patients admitted to the Emergency Department (ED). This condition is linked to adverse outcomes such as reduced long-term functionality, higher mortality rates, extended hospital stays, and increased medical costs. The identification of risk factors is crucial for the early recognition and management of delirium in ED patients. Aging, cognitive decline, polypharmacy, and sensory impairment are some of the most common general risk factors described in the literature. Although validated delirium assessment tools already exist, they are not practical for the fast-paced ED environment because of their extended evaluation period or specialized training request. Moreover, clear guidance is needed to select the most suitable tool for detecting delirium, balancing between the accuracy and the swiftness required in an overcrowded, high-stress, and understaffed healthcare setting. This narrative review aims to analyze the updated literature on delirium risk factors in older ED patients and focuses on the methods for better screening, managing, and treating this condition in the ED.

New-onset delirium during hospitalization in older adults: incidence and risk factors

OBJECTIVE

Delirium is a clinical diagnosis that can occur frequently in hospitalized patients. A retrospective study was completed to identify the incidence of patients aged greater than 65 developing delirium during hospitalization.

METHODS

This study was conducted at a single tertiary care teaching hospital. Charts of discharged patients from November to December 2018 were evaluated and patients less than age 65 or with delirium present on admission were excluded. The search terms altered, delirium, encephalopathy, and confusion were used to identify patients who developed delirium during the hospitalization. Characteristics of the patients with delirium were also collected.

RESULTS

The incidence of new-onset delirium in patients over age 65 during hospitalization was 10%. Patients who developed delirium during their hospital stay were found to have a higher risk of mortality (p = 0.0028) and severity of illness (p = 0.014). A strong correlation between the length of stay (LOS) and incidence of delirium was also noted.

CONCLUSION

The strong correlation between a longer LOS and a higher incidence of delirium should guide the development of new innovative strategies to shorten the LOS and thus reduce the risk of delirium, in high-risk older hospitalized patients.

Delirium occurrence in older Irish adults admitted to an acute medical hospital: a prospective cohort study

OBJECTIVES

Delirium, which is associated with adverse health outcomes, is poorly detected in hospital settings. This study aimed to determine delirium occurrence among older medical inpatients and to capture associated risk factors.

METHODS

This prospective cohort study was performed at an Irish University Hospital. Medical inpatients 70 years and over were included. Baseline assessments within 72 hours of admission included delirium status and severity as determined by the Revised Delirium Rating Scale (DRS-R-98), cognition, physical illness severity and physical functioning. Pre-existing cognitive impairment was determined with Short Informant Questionnaire on Cognitive Decline (IQCODE). Serial assessment of delirium status, cognition and the physical illness severity were undertaken every 3 (±1) days during participants' hospital admission.

RESULTS

Of 198 study participants, 92 (46.5%) were women and mean age was 80.6 years (s.d. 6.81; range 70-97). Using DRS-R-98, 17.7% (n = 35) had delirium on admission and 11.6% (n = 23) had new-onset delirium during admission. In regression analysis, older age, impaired cognition and lower functional ability at admission were associated with a significant likelihood of delirium.

CONCLUSIONS

In this study, almost one-third of older medical inpatients in an acute hospital had delirium during admission. Findings that increasing age, impaired cognition and lower functional ability at admission were associated with increased delirium risk suggest target groups for enhanced delirium detection and prevention strategies. This may improve clinical outcomes.

Prevalence and Risk Factors of Delirium in Patients Admitted to Intensive Care Units: A Multicentric Cross-Sectional Study

Background Delirium is a common and serious complication among critically ill patients in the intensive care unit. Knowledge of the risk factors of delirium can help tremendously in the diagnosis of delirium. Methods In April of 2023, a cross-sectional multicenter study was conducted in eight intensive care units (ICUs) across Pakistan. Delirium was assessed using the intensive care delirium screening checklist. Demographic and clinical data were collected, and multivariable logistic regression analysis was performed to identify predictors of delirium. A total of 256 patients were enrolled in the study. Results The mean age of participants was 56 (S.D. 12) years. The point prevalence of delirium was 39%, and the point prevalence did not vary significantly among the participating intensive care units. Advanced age, higher Acute Physiology and Chronic Health Evaluation - IV (APACHE IV) scores, and higher Richmond Agitation-Sedation Scale (RASS) scores at enrollment were identified as significant predictors of delirium. Conclusion The high prevalence of delirium, observed at 39.0%, emphasizes the importance of proactive screening and effective management strategies in the ICU setting. Healthcare providers in Pakistan should be mindful of these risk factors and implement preventive measures to minimize the occurrence of delirium in critically ill patients. Further research and implementation of targeted interventions are warranted to improve patient outcomes and enhance the overall quality of care in this population.

Knowledge, barriers, and training needs of nurses working in delirium care

BACKGROUND

Nurses' competency in delirium care is important because delirium can extend hospitalization and increase patient mortality.

AIM

This study aimed at identifying and comparing the perceived knowledge, barriers, importance, performance, and training priorities between the intensive care unit (ICU) and ward nurses working in delirium care.

STUDY DESIGN

This cross-sectional descriptive study included 71 ICU nurses and 149 ward nurses at one university hospital. Nurses' self-reported knowledge, barriers, importance, and performance of delirium care were surveyed. Data were analysed using descriptive statistics, chi-squared test or Fisher's exact test, Wilcoxon signed-rank tests, Mann-Whitney U tests, and the importance-performance analysis matrix.

RESULTS

Compared to ward nurses, ICU nurses reported lower overall knowledge level (57.1% vs 60.7%, z = -2.005, P = .045) but higher overall gap between the importance and performance of delirium care (0.5 vs 0.2, z = -4.008, P < .001). The level of overall barriers to delirium care was similar between the two groups (3.8 vs 3.8, z = -1.190, P = .234). The highest training priority, showing high importance but low performance in the importance-performance matrix, was "family involvement and education" for ICU nurses and "non-pharmacological management" for ward nurses.

CONCLUSIONS

The highest training priority for delirium care was different between ICU and ward nurses. To enhance the delirium care competency of hospital nurses, the nurse educator should develop training programs that target knowledge deficits, perceived barriers, and training priorities.

RELEVANCE TO CLINICAL PRACTICE

Acute cognitive disturbances are common in patients hospitalized in wards and ICUs and can lead to adverse patient outcomes if not properly assessed and managed. Nurse educators need to develop and implement a training program based on the needs assessment and priorities identified in this study so that ICU and ward nurses can obtain the optimal level of delirium care competency.

Delirium Screening and Pharmacotherapy in the ICU: The Patients Are Not the Only Ones Confused

Background: Delirium is difficult to measure in the Intensive Care Unit (ICU). It is possible that by considering the rate of screening, incidence, and rate of treatment with antipsychotic medications (APMs) for suspected delirium, a clearer picture can emerge. Methods: A retrospective, observational study was conducted at two ICUs in Australia, between April and June of 2020. All adult ICU patients were screened; those who spoke English and did not have previous neurocognitive pathology or intracranial pathology were included in the analysis. Data were collected from the hospitals' electronic medical records. The primary outcome was incidence of delirium based on the use of the Confusion Assessment Method for ICU (CAM-ICU). Secondary outcomes included measures of screening for delirium, treatment of suspected delirium with APMs, and identifying clinical factors associated with both delirium and the use of APMs. Results: From 736 patients that were screened, 665 were included in the analysis. The incidence of delirium was 11.3% (75/665); on average, the Richmond Agitation and Sedation Scale (RASS) was performed every 2.9 h and CAM-ICU every 40 h. RASS was not performed in 8.4% (56/665) of patients and CAM-ICU was not performed in 40.6% (270/665) of patients. A total of 17% (113/665) of patients were prescribed an APM, with quetiapine being the most used. ICU length of stay (LOS), APACHE-III score, and the use of alpha-2 agonists were associated with the presence of delirium, while ICU LOS, the use of alpha-2 agonists, and the presence of delirium were associated with patients receiving APMs. Conclusions: The incidence of delirium was lower than previously reported, at 11.3%. The rate of screening for delirium was low, while the use of APMs for delirium was higher than the incidence of delirium. It is possible that the true incidence is higher than what was measured. Critical prospective assessment is required to optimize APM indications in the ICU.

Analysis of risk factors for postoperative delirium in middle-aged and elderly fracture patients in the perioperative period

To investigate the incidence rate and risk factors of postoperative delirium in middle-aged and elderly patients with fracture. A total of 648 middle-aged and elderly fracture patients who underwent surgical treatment in our hospital from January 2018 to December 2020 were included in the study, aged 50-103 years, mean 70.10 ± 11.37 years. The incidence of postoperative delirium was analyzed. Univariate analysis was used to screen the risk factors of gender, age, interval between injury and operation, preoperative complications, fracture site, anesthesia method, operation time, intraoperative blood loss, hidden blood loss and hormone use. For the factors with P < 0.05, multivariate logistic regression analysis was used to determine the main independent risk factors. 115 cases (17.74%) of 648 patients had postoperative delirium. Univariate analysis showed that patients with delirium and patients without delirium had significant correlation in age, medical disease comorbidity, fracture type, anesthesia method, operation time and perioperative blood loss (P < 0.05). Multivariate logistic regression analysis showed that age (OR = 1.061), preoperative complications (OR = 1.667), perioperative blood loss (OR = 1.002) were positively correlated with postoperative delirium. It shows that older age, more preoperative complications, longer operation time and more perioperative bleeding are more likely to lead to postoperative delirium; patients with general anesthesia were more likely to develop postoperative delirium than patients with local anesthesia (OR = 1.628); and patients with hip and pelvic fractures are more likely to develop a postoperative delirious state (OR = 1.316). Advanced age, complex orthopedic surgery, more medical comorbidities, general anesthesia and greater perioperative blood loss may be independent risk factors for the development of delirium after internal fixation of fractures in middle-aged and elderly patients.

Total intravenous anesthesia versus inhalation anesthesia: how do outcomes compare?

RECENT FINDINGS

Surgical procedures that involve general anesthesia are performed with either volatile anesthetics or propofol-based total intravenous anesthesia. Both techniques are safe and provide appropriate conditions for surgery. Despite being a well established anesthetic, the use of propofol-based total intravenous anesthesia (TIVA) remains low. Possible explanations include the perceived increase risk of awareness, lack of target controlled infusion devices, increased turnover time for device set up and individual preference.

SUMMARY

There are some scenarios where patients could potentially benefit from propofol-based TIVA rather than a volatile anesthetic (e.g. postoperative nausea and vomiting) and some other clinical scenarios where the use of propofol-based anesthesia remains controversial since the strength of the evidence remains low.

PURPOSE

In this review we will summarize the clinical evidence comparing the effect of propofol-based TIVA and volatile anesthetic on postoperative outcomes such as postoperative nausea and vomiting, postoperative pain, quality of recovery, postoperative cognitive dysfunction and cancer outcomes.

Delirium, confusion, or altered mental status as a risk for abnormal head computed tomogram findings in older adults in the emergency department: A Geriatric Emergency Department Guidelines 2.0 systematic review and meta-analysis

BACKGROUND

Altered mental status (including delirium) is a common presentations among older adults to the emergency department (ED). We aimed to report the association between altered mental status in older ED patients and acute abnormal findings on head computed tomogram (CT).

METHODS

A systematic review was conducted using Ovid Medline, Embase, Clinicaltrials.gov, Web of Science, and Cochrane Central from conception to April 8th, 2021. We included citations if they described patients aged 65 years or older who received head imaging at the time of ED assessment, and reported whether patients had delirium, confusion, or altered mental status. Screening, data extraction, and bias assessment were performed in duplicate. We estimated the odds ratios (OR) for abnormal neuroimaging in patients with altered mental status.

RESULTS

The search strategy identified 3031 unique citations, of which two studies reporting on 909 patients with delirium, confusion or altered mental status were included. No identified study formally assessed for delirium. The OR for abnormal head CT findings in patients with delirium, confusion or altered mental status was 0.35 (95% CI 0.031 to 3.97) compared to patients without delirium, confusion or altered mental status.

CONCLUSION

We did not find a statistically significant association between delirium, confusion or altered mental status and abnormal head CT findings in older ED patients.

Incidence of postoperative delirium in older adults undergoing surgical procedures: A systematic literature review and meta-analysis

BACKGROUND

With the increase in life expectancy around the globe, the incidence of postoperative delirium (POD) among older people (≥65 years) is growing. Previous studies showed a wide variation in the incidence of POD, from 4% to 53%, with a lack of specific evidence about the incidence of POD by specific surgery type among older people. The aim of this systematic review and meta-analysis was to determine the incidence of POD by surgery type within populations 65 years and over.

METHODS

Databases including PubMed, Cochrane library, Embase, and CINAHL were searched until October 2020. Due to the relatively higher number of meta-analyses undertaken in this area of research, a streamlined systematic meta-analysis was proposed.

RESULTS

A total of 28 meta-analyses (comprising 284 individual studies) were reviewed. Data from relevant individual studies (n = 90) were extracted and included in the current study. Studies were grouped into eight surgery types and the incidence of POD for orthopedic, vascular, spinal, cardiac, colorectal, abdominal, urologic, and mixed surgeries was 20%, 14%, 13%, 32%, 14%, 30%, 10%, and 26%, respectively. POD detection instruments were different across the studies, with Confusion Assessment Method (CAM & CAM-ICU) being the most frequently adopted.

LINKING EVIDENCE TO ACTION

This study showed that POD incidence in older people undergoing surgery varied widely across surgery type. The more complex surgeries like cardiac and abdominal surgeries were associated with a higher risk of POD. This highlights the need to include the level of surgery complexity as a risk factor in preoperative assessments.

Predictors of hospital readmission for patients diagnosed with delirium: An electronic health record data analysis

INTRODUCTION

Delirium is an acute and fluctuating change in attention and cognition that increases the risk of functional decline, institutionalisation and death in hospitalised patients. After delirium, patients have a significantly higher risk of readmission to hospital. Our aim was to investigate factors associated with hospital readmission in people with delirium.

METHODS

We carried out an observational retrospective cohort study using linked mental health care and hospitalisation records from South London. Logistic regression models were used to predict the odds of 30-day readmission and Cox proportional hazard models to calculate readmission risks when not restricting follow-up time.

RESULTS

Of 2814 patients (mean age 78.9 years SD ±11.8) discharged from hospital after an episode of delirium, 823 (29.3%) were readmitted within 30 days. Depressed mood (odds ratio (OR) 1.34 (95% confidence interval (CI) 1.08-1.66)), moderate-to-severe physical health problems (OR 1.67 (95% CI 1.18-2.2.36)) and a history of serious circulatory disease (OR 1.29 (95% CI 1.07-1.55)) were associated with higher odds of hospital readmission, whereas a diagnosis of delirium superimposed on dementia (OR 0.67 (95% CI 0.53-0.84)) and problematic alcohol/substance (OR 0.54 (95% CI 0.33-0.89)) use were associated with lower odds. Cox proportionate hazard models showed similar results.

CONCLUSION

Almost one-third of patients with delirium were readmitted within a short period of time, a more detailed understanding of the underlying risk factors could help prevent readmissions. Our findings indicate that the aetiology (as alcohol-related delirium), the recognition that delirium occurred in the context of dementia, as well as potentially modifiable factors, as depressed mood affect readmission risk, and should be assessed in clinical settings.

Association between preoperative anxiety and postoperative delirium in older patients: a systematic review and meta-analysis

BACKGROUND

Postoperative delirium (POD) is a common postoperative complication associated with multiple adverse consequences on patient outcomes and higher medical expenses. Preoperative anxiety has been suggested as a possible precipitating factor for the development of POD. As such, we aimed to explore the association between preoperative anxiety and POD in older surgical patients.

METHODS

Electronic databases including MEDLINE (via PubMed), EMBASE (via Embase.com), Web of Science Core Collection, Cumulative Index to Nursing and Allied Health Literature (CINAHL Complete; via EBSCOhost) and clinical trial registries were systematically searched to identify prospective studies examining preoperative anxiety as a risk factor for POD in older surgical patients. We used Joanna Briggs Institute Critical Appraisal Checklist for Cohort Studies to assess the quality of included studies. The association between preoperative anxiety and POD was summarized with odds ratios (ORs) and 95% confidence intervals (CIs) using DerSimonian-Laird random-effects meta-analysis.

RESULTS

Eleven studies were included (1691 participants; mean age ranging between 63.1-82.3 years). Five studies used a theoretical definition for preoperative anxiety, with the Anxiety subscale of Hospital Anxiety and Depression Scale (HADS-A) as the instrument being most often used. When using dichotomized measures and within the HADS-A subgroup analysis, preoperative anxiety was significantly associated with POD (OR = 2.17, 95%CI: 1.01-4.68, I² = 54%, Tau² = 0.4, n = 5; OR = 3.23, 95%CI: 1.70-6.13, I² = 0, Tau² = 0, n = 4; respectively). No association was observed when using continuous measurements (OR = 0.99, 95%CI: 0.93-1.05, I² = 0, Tau² = 0, n = 4), nor in the subgroup analysis of STAI-6 (six-item version of state scale of Spielberger State-Trait Anxiety Inventory, OR = 1.07, 95%CI: 0.93-1.24, I² = 0, Tau² = 0, n = 2). We found the overall quality of included studies to be moderate to good.

CONCLUSIONS

An unclear association between preoperative anxiety and POD in older surgical patients was found in our study. Given the ambiguity in conceptualization and measurement instruments used for preoperative anxiety, more research is warranted in which a greater emphasis should be placed on how preoperative anxiety is operationalized and measured.

Independent External Validation of a Preoperative Prediction Model for Delirium After Cardiac Surgery: A Prospective Observational Cohort Study

OBJECTIVE

This investigation provided independent external validation of an existing preoperative risk prediction model.

DESIGN

A prospective observational cohort study of patients undergoing cardiac surgery covering the period between April 16, 2018 and January 18, 2022.

SETTING

Two academic hospitals in Switzerland.

PARTICIPANTS

Adult patients (≥60 years of age) who underwent elective cardiac surgery, including coronary artery bypass graft, mitral or aortic valve replacement or repair, and combined procedures.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome measure was the incidence of postoperative delirium (POD) in the intensive or intermediate care unit, diagnosed using the Intensive Care Delirium Screening Checklist. The prediction model contained 4 preoperative risk factors to which the following points were assigned: Mini-Mental State Examination (MMSE) score ≤23 received 2 points; MMSE 24-27, Geriatric Depression Scale (GDS) >4, prior stroke and/or transient ischemic attack (TIA), and abnormal serum albumin (≤3.5 or ≥4.5 g/dL) received 1 point each. The missing data were handled using multiple imputation. In total, 348 patients were included in the study. Sixty patients (17.4%) developed POD. For point levels in the prediction model of 0, 1, 2, and ≥3, the cumulative incidence of POD was 12.6%, 22.8%, 25.8%, and 35%, respectively. The validation resulted in a pooled area under the receiver operating characteristics curve of 0.60 (median CI, 0.525-0.679).

CONCLUSIONS

The evaluated predictive model for delirium after cardiac surgery in this patient cohort showed only poor discriminative capacity but fair calibration.

Risk factors and outcomes of delirium in hospitalized older adults with COVID-19: A systematic review and meta-analysis

Background

Older adults with COVID-19 are more likely to present with atypical symptoms, notably delirium. The main objective of this meta-analysis is to identify risk factors for delirium and outcomes of delirium in hospitalized older adults (65 years or above) with COVID-19.

Methods

Comprehensive literature search of Embase, CINAHIL, Medline and Web of Science was performed for published literature until 31st August 2021. Two independent researchers evaluated study eligibility and assessed study quality using the Newcastle Ottawa Scale (NOS) for cohort studies and Joanna Briggs Institute (JBI) critical appraisal tools for case series. The association of various predisposing factors with delirium in this cohort was reported as odds ratio (OR) and its 95% confidence interval (CI).

Results

A total of 31 studies from 11 countries were included in this review. Most of the included studies investigated patients from non-ICU settings (n = 24; 77.4%). Frailty (OR 3.52, 95% CI: 1.96-6.31, p<0.0001, I²=71.63%), cognitive impairment including dementia (OR 6.17, 95% CI: 2.92-13.07, p<0.00001, I²=88.63%) and being nursing home residents (OR 1.72, 95% CI: 1.31-2.24, p<0.0001, I²=0) were significantly associated with increased likelihood of developing delirium in older adults with COVID-19. The presence of delirium also significantly increases mortality risk in hospitalized older adults with COVID-19 (OR 2.51, 95% CI: 1.51-4.17, p<0.0001, I²=89.3%).

Conclusion

Our review identifies key factors associated with increased risk of developing delirium in hospitalized older adults with COVID-19. Identification of patients at risk of delirium and attention to these factors early during admission may improve outcomes for this vulnerable cohort.

The use of dexmedetomidine in the emergency department: A systematic review

BACKGROUND

Dexmedetomidine (DEX), a centrally acting alpha-2 agonist, is increasingly used for sedation in multiple clinical settings. Evidence from the intensive care unit and operative settings suggests DEX may have significant advantages over traditional GABAergic sedatives such as benzodiazepines. There has been limited research on the use of DEX in the emergency department (ED).

METHODS

We performed a systematic review of the medical literature to identify all published evidence regarding the use of DEX in the ED. We included randomized and nonrandomized studies and studies reporting any use of DEX in the ED, even when it was not the primary focus of the study. Two authors reviewed studies for inclusion, and a single author assessed studies for quality and risk of bias and abstracted data.

RESULTS

We identified 35 studies meeting inclusion criteria, including 11 randomized controlled trials, 13 cohort and other nonrandomized studies, and 11 case reports and case series. Significant heterogeneity in interventions, comparators, indications, and outcomes precluded data pooling and meta-analysis. We found modest evidence that DEX was efficacious in facilitating medical imaging and mixed and limited evidence regarding its efficacy for procedural sedation and sedation of nonintubated medical and psychiatric patients. Our results suggested that DEX is associated with bradycardia and hypotension, which are generally transient and infrequently require medical intervention.

CONCLUSIONS

A limited body of generally poor- to moderate-quality evidence suggests that the use of DEX may be efficacious in certain clinical scenarios in the ED and that DEX use in the ED is likely safe. Further high-quality research into DEX use in the ED setting is needed, with a particular focus on clear and consistent selection of indications, identification of clear and clinically relevant primary outcomes, and careful assessment of the clinical implications of the hemodynamic effects of DEX therapy.

Delirium Prevention and Management in Frail Surgical Patients

Delirium, an acute, fluctuating impairment in cognition and awareness, is one of the most common causes of postoperative brain dysfunction. It is associated with increased hospital length of stay, health care costs, and mortality. There is no FDA-approved treatment of delirium, and management relies on symptomatic control. Several preventative techniques have been proposed, including the choice of anesthetic agent, preoperative testing, and intraoperative monitoring. Frailty, a state of increased vulnerability to adverse events, is an independent and potentially modifiable risk factor for the development of delirium. Diligent preoperative screening techniques and implementation of prevention strategies could help improve outcomes in high-risk patients.

Predicting Intensive Care Delirium with Machine Learning: Model Development and External Validation

BACKGROUND

Delirium poses significant risks to patients, but countermeasures can be taken to mitigate negative outcomes. Accurately forecasting delirium in intensive care unit (ICU) patients could guide proactive intervention. Our primary objective was to predict ICU delirium by applying machine learning to clinical and physiologic data routinely collected in electronic health records.

METHODS

Two prediction models were trained and tested using a multicenter database (years of data collection 2014 to 2015), and externally validated on two single-center databases (2001 to 2012 and 2008 to 2019). The primary outcome variable was delirium defined as a positive Confusion Assessment Method for the ICU screen, or an Intensive Care Delirium Screening Checklist of 4 or greater. The first model, named "24-hour model," used data from the 24 h after ICU admission to predict delirium any time afterward. The second model designated "dynamic model," predicted the onset of delirium up to 12 h in advance. Model performance was compared with a widely cited reference model.

RESULTS

For the 24-h model, delirium was identified in 2,536 of 18,305 (13.9%), 768 of 5,299 (14.5%), and 5,955 of 36,194 (11.9%) of patient stays, respectively, in the development sample and two validation samples. For the 12-h lead time dynamic model, delirium was identified in 3,791 of 22,234 (17.0%), 994 of 6,166 (16.1%), and 5,955 of 28,440 (20.9%) patient stays, respectively. Mean area under the receiver operating characteristics curve (AUC) (95% CI) for the first 24-h model was 0.785 (0.769 to 0.801), significantly higher than the modified reference model with AUC of 0.730 (0.704 to 0.757). The dynamic model had a mean AUC of 0.845 (0.831 to 0.859) when predicting delirium 12 h in advance. Calibration was similar in both models (mean Brier Score [95% CI] 0.102 [0.097 to 0.108] and 0.111 [0.106 to 0.116]). Model discrimination and calibration were maintained when tested on the validation datasets.

CONCLUSIONS

Machine learning models trained with routinely collected electronic health record data accurately predict ICU delirium, supporting dynamic time-sensitive forecasting.

EDITOR’S PERSPECTIVE

Effect of physical and occupational therapy on delirium duration in older emergency department patients who are hospitalized

Objective

Delirium in older emergency department (ED) adults is associated with poorer long-term physical function and cognition. We sought to evaluate if the time to and intensity of physical and/or occupational therapy (PT/OT) are associated with the duration of ED delirium into hospitalization (ED delirium duration).

Methods

This is a secondary analysis of a prospective cohort study conducted from March 2012 to November 2014 at an urban, academic, tertiary care hospital. Patients aged ≥65 years presenting to the ED and who received PT/OT during their hospitalization were included. Days from enrollment to the first PT/OT session and PT/OT duration relative to hospital length of stay (PT/OT intensity) were abstracted from the medical record. ED delirium duration was defined as the duration of delirium detected in the ED using the Brief Confusion Assessment Method. Data were analyzed using a proportional odds logistic regression adjusted for multiple variables. Adjusted odds ratios (ORs) were calculated with 95% confidence intervals (95%CI).

Results

The median log PT/OT intensity was 0.5% (interquartile range [IQR]: 0.3%, 0.9%) and was associated with shorter delirium duration (adjusted OR, 0.39; 95% CI, 0.21-0.73). The median time to the first PT/OT session was 2 days (IQR: 1, 3 days) and was not associated with delirium duration (adjusted OR, 1.02; 95% CI, 0.82-1.27).

Conclusion

In older hospitalized adults, higher PT/OT intensity may be a useful intervention to shorten delirium duration. Time to first PT/OT session was not associated with delirium duration but was initiated a full 2 days after the ED presentation.

Cost effectiveness of home care versus hospital care: a retrospective analysis

BACKGROUND

Increased utilization of health services due to population growth affects the allocation of national resources and budgets. Hence, it is important for national policy. Home hospitalization is one of the solutions for dealing with the growing demand for hospital beds and reducing the duration of hospitalization and its costs. It is gradually becoming part of the regular care in many health systems, yet, studies on the economic aspects of Community-Based Home Hospitalization (CBHH) implementation in Israel are few. The aim of this study is to examine costs of CBHH in comparison to costs of inpatient hospital care in the Israeli public health system.

METHODS

Retrospective data was collected using document research in databases. A review of the costs of patients in CBHH at Maccabi Healthcare Services (MHS) was conducted. A total of 3374 patients were included in this study: 1687 patients who were in CBHH, and 1687 age- and sex-matched patients who were hospitalized in an internal department (the control group). The study population included the patients admitted to CBHH from January 2018 to July 2020, and patients admitted to internal medicine departments during the same period.

RESULTS

The number of hospitalizations during the follow up period were statistically significantly lower in the CBHH group compared with the control group (M = 1.18, SD = 0.56 vs. M = 1.61, SD = 1.29, p < 0.001). In addition, the mean number of hospitalization days was also statistically significantly lower for 4.3 (SD = 4.5) for CBHH patients compared to the control group (M = 4.3 days, SD = 4.5 vs. M = 7.5 days, SD = 10.3, p < 0.001). Furthermore, the mean cost per day was statistically significantly higher for inpatient hospitalization compared to CBHH (M = 1829.1, SD = 87.5 vs. M = 783.2, SD = 178.3, p < 0.001). Older patients, patients with diabetes and patients hospitalized in hospitals had a higher number of hospitalization days.

CONCLUSIONS

The costs of CBHH seem to be lower than those of inpatient care. Managing CBHH is characterized by constantly measuring financial feasibility that would be an impetus for further development of this service.

Melatonin or Ramelteon for Delirium Prevention in the Intensive Care Unit: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Melatonin modulates the circadian rhythm and has been studied as a preventive measure against the development of delirium in hospitalized patients. Such an effect may be more evident in patients admitted to the ICU, but findings from the literature are conflicting. We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs). We assessed whether melatonin or ramelteon (melatonin agonist) reduce delirium incidence as compared to a placebo in ICU patients. Secondary outcomes were ICU length of stay, duration of mechanical ventilation (MV) and mortality. Estimates are presented as risk ratio (RR) or mean differences (MD) with 95% confidence interval (CI). Nine RCTs were included, six of them reporting delirium incidence. Neither melatonin nor ramelteon reduced delirium incidence (RR 0.76 (0.54, 1.07), p = 0.12; I² = 64%), although a sensitivity analysis conducted adding other four studies showed a reduction in the risk of delirium (RR = 0.67 (95%CI 0.48, 0.92), p = 0.01; I² = 67). Among the secondary outcomes, we found a trend towards a reduction in the duration of MV (MD -2.80 (-6.06, 0.47), p = 0.09; I² = 94%) but no differences in ICU-LOS (MD -0.26 (95%CI -0.89, 0.37), p = 0.42; I² = 75%) and mortality (RR = 0.85 (95%CI 0.63, 1.15), p = 0.30; I² = 0%). Melatonin and ramelteon do not seem to reduce delirium incidence in ICU patients but evidence is weak. More studies are needed to confirm this finding.

Understanding the association between admission source and in-hospital delirium: A cross-sectional study

Patients admitted via interhospital transfer (IHT) experience increased risk-adjusted mortality, adverse events, length of stay, and discharge to facility; however, the etiology is not well understood. We hypothesize that IHTs are more likely to experience in-hospital delirium as compared with admissions to the hospital via the emergency department (ED) and clinic. This is a cross-sectional study of all adult admissions to medical, surgical, neurological, and obstetrics and gynecology services at an academic medical center who were screened for delirium between August 2018 and January 2020. Unit of analysis was admission source (IHT vs ED vs clinic) as the independent variable and the primary outcome was in-hospital delirium, assessed with initial brief confusion assessment method (bCAM) screening. 30,100 hospitalizations were included in this study with 3925 admissions (13.0%) screening positive for delirium at the initial bCAM assessment. The prevalence of delirium was much higher in IHTs at 22.3% (1334/5971) when compared with clinic at 5.8% (244/4214) and ED at 11.8% (2347/19,915) admissions. Multivariable logistic regression adjusting for demographics and comorbidities showed that IHT admissions had higher odds (OR 1.91, 95% CI 1.74 to 2.10) and clinic admissions had lower odds (OR 0.56, 95% CI 0.48 to 0.64) of in-hospital delirium compared with ED admissions. Increased odds of delirium in IHT admissions may contribute to the observed increased length of stay, discharge to facility, and mortality. These results emphasize the importance of routine screening and possible intervention prior to patient transfer.

Associations of body mass index with severe outcomes of COVID-19 among critically ill elderly patients: A prospective study

Background and Aim

Few studies assessed the associations of overweight and obesity with severe outcomes of coronavirus disease 2019 (COVID-19) among elderly patients. This study was conducted to assess overweight and obesity in relation to risk of mortality, delirium, invasive mechanical ventilation (IMV) requirement during treatment, re-hospitalization, prolonged hospitalization, and ICU admission among elderly patients with COVID-19.

Methods

This was a single-center prospective study that was done on 310 elderly patients with COVID-19 hospitalized in the intensive care unit (ICU). We collected data on demographic characteristics, laboratory parameters, nutritional status, blood pressure, comorbidities, medications, and types of mechanical ventilation at baseline. Patients were followed up during ICU admission and until 45 days after the first visit, and data on delirium incidence, mortality, need for a form of mechanical ventilation, discharge day from ICU and hospital, and re-hospitalization were recorded for each patient.

Results

During the follow-up period, we recorded 190 deaths, 217 cases of delirium, and 35 patients who required IMV during treatment. After controlling for potential confounders, a significant association was found between obesity and delirium such that obese patients with COVID-19 had a 62% higher risk of delirium compared with normal-weight patients (HR: 1.62, 95% CI: 1.02-2.57). This association was not observed for overweight. In terms of other outcomes including ICU/45-day mortality, IMV therapy during treatment, re-hospitalization, prolonged hospitalization, and ICU admission, we found no significant association with overweight and obesity either before or after controlling for potential confounders.

Conclusion

We found that obesity may be a risk factor for delirium among critically ill elderly patients with COVID-19.

A novel approach for the detection of cognitive impairment and delirium risk in older patients undergoing spine surgery

BACKGROUND

Postoperative delirium is a common postsurgical complication in older patients and is associated with high morbidity and mortality. The objective of this study was to determine whether a digital cognitive assessment and patient characteristics could identify those at-risk.

METHODS

Patients 65 years and older undergoing spine surgeries ≥3 h were evaluated as part of a single-center prospective observational cohort study at an academic medical center, from January 1, 2019, to December 31, 2020. Of 220 eligible patients, 161 were enrolled and 152 completed the study. The primary outcome of postoperative delirium was measured by the Confusion Assessment Method for the Intensive Care Unit or the Nursing Delirium Screening Scale, administered by trained nursing staff independent from the study protocol. Baseline cognitive impairment was identified using the tablet-based TabCAT Brain Health Assessment.

RESULTS

Of the 152 patients included in this study, 46% were women. The mean [SD] age was 72 [5.4] years. Baseline cognitive impairment was identified in 38% of participants, and 26% had postoperative delirium. In multivariable analysis, impaired Brain Health Assessment Cognitive Score (OR 2.45; 95% CI, 1.05-5.67; p = 0.037), depression (OR 4.54; 95% CI, 1.73-11.89; p = 0.002), and higher surgical complexity Tier 4 (OR 5.88; 95% CI, 1.55-22.26; p = 0.009) were associated with postoperative delirium. The multivariate model was 72% accurate for predicting postoperative delirium, compared to 45% for the electronic medical record-based risk stratification model currently in use.

CONCLUSION

In this prospective cohort study of spine surgery patients, age, cognitive impairment, depression, and surgical complexity identified patients at high risk for postoperative delirium. Integration of scalable digital assessments into preoperative workflows could identify high-risk patients, automate decision support for timely interventions that can improve patient outcomes and lower hospital costs, and provide a baseline cognitive assessment to monitor for postoperative cognitive change.

Effect of remimazolam on the incidence of delirium after transcatheter aortic valve implantation under general anesthesia: a retrospective exploratory study

PURPOSE

Delirium after transcatheter aortic valve implantation (TAVI) should be prevented because it is associated with worse patient outcomes. Perioperative administration of benzodiazepines is a risk factor for postoperative delirium; however, the association between remimazolam, a newer ultrashort-acting benzodiazepine for general anesthesia, and postoperative delirium remains unclear. This study aimed to evaluate whether remimazolam administration during TAVI under general anesthesia affected the incidence of postoperative delirium.

METHODS

This single-center retrospective study recruited all adult patients who underwent transfemoral TAVI (TF-TAVI) under general anesthesia between March 2020 and May 2022. Patients were divided into the remimazolam (R) and propofol (P) groups according to the sedative used for anesthesia. In the R group, all patients received flumazenil after surgery. The primary endpoint was the incidence of delirium within 3 days after surgery. Factors associated with delirium after TF-TAVI were examined by multiple logistic regression analysis.

RESULTS

Ninety-eight patients were included in the final analysis (R group, n = 40; P group, n = 58). The incidence of postoperative delirium was significantly lower in the R group than in the P group (8% vs. 26%, p = 0.032). Multiple logistic regression analysis revealed that remimazolam (odds ratio 0.17, 95% CI 0.04-0.80, p = 0.024) was independently associated with the incidence of postoperative delirium, even after adjustment for age, sex, preoperative cognitive function, history of stroke, and TF-TAVI approach.

CONCLUSION

Remimazolam may benefit TF-TAVI in terms of postoperative delirium; however, its usefulness must be further evaluated in extensive prospective studies.

Predisposing and precipitating risk factors for delirium in gastroenterology and hepatology: Subgroup analysis of 718 patients from a hospital-wide prospective cohort study

BACKGROUND AND AIMS

Delirium is the most common acute neuropsychiatric syndrome in hospitalized patients. Higher age and cognitive impairment are known predisposing risk factors in general hospital populations. However, the interrelation with precipitating gastrointestinal (GI) and hepato-pancreato-biliary (HPB) diseases remains to be determined.

PATIENTS AND METHODS

Prospective 1-year hospital-wide cohort study in 29'278 adults, subgroup analysis in 718 patients hospitalized with GI/HPB disease. Delirium based on routine admission screening and a DSM-5 based construct. Regression analyses used to evaluate clinical characteristics of delirious patients.

RESULTS

Delirium was detected in 24.8% (178/718). Age in delirious patients (median 62 years [IQR 21]) was not different to non-delirious (median 60 years [IQR 22]), p = 0.45). Dementia was the strongest predisposing factor for delirium (OR 66.16 [6.31-693.83], p < 0.001). Functional impairment, and at most, immobility increased odds for delirium (OR 7.78 [3.84-15.77], p < 0.001). Patients with delirium had higher in-hospital mortality rates (18%; OR 39.23 [11.85-129.93], p < 0.001). From GI and HPB conditions, cirrhosis predisposed to delirium (OR 2.11 [1.11-4.03], p = 0.023), while acute renal failure (OR 4.45 [1.61-12.26], p = 0.004) and liver disease (OR 2.22 [1.12-4.42], p = 0.023) were precipitators. Total costs were higher in patients with delirium (USD 30003 vs. 10977; p < 0.001).

CONCLUSION

Delirium in GI- and HPB-disease was not associated with higher age per se, but with cognitive and functional impairment. Delirium needs to be considered in younger adults with acute renal failure and/or liver disease. Clinicians should be aware about individual risk profiles, apply preventive and supportive strategies early, which may improve outcomes and lower costs.

Association of delirium screening on hospitalized adults and postacute care utilization: A retrospective cohort study

BACKGROUND

Patients with delirium have increased hospital length of stay (LOS), morbidity and mortality. Impact of delirium on postacute care (PAC) utilization is not fully characterized. Impact of screening for delirium on general medicine patients is unknown. The objective of this study was to assess impact of screening for delirium on inpatient PAC utilization.

METHODS

This was a single center, retrospective cohort study at an academic tertiary care center in Charleston, SC. Patients were selected from adults hospitalized from home and discharged alive between June 2014 and June 2018. The brief confusion assessment method (bCAM) screening was conducted and documented by nursing on admission and every shift thereafter. Outcome measure was the proportion of patients discharged to facility.

RESULTS

Of 93,388 non-ICU adult admission between June 2014 and June 2018, 4.4% of those not screened for delirium were discharged to facility versus 15.0% in those screened and 41.4% in those screening positive. Multivariable regression analysis showed that patients screened for delirium were 2.3 times more likely to discharge to facility (95% CI (2.145, 2.429)) while those with a positive bCAM were 3.3 times more likely than those with a negative bCAM to discharge to facility (95% CI (2.949, 3.712)).

CONCLUSIONS

After adjusting for demographics, medication orders and comorbidities there was an association between screening for delirium, positive delirium screen and discharge to facility. An appreciation of where and why patients are discharged is imperative to optimize both patient care and cost utilization.

Delirium in COVID-19 and post-liver transplant patients: an observational study

OBJECTIVE

Delirium is a major complication in hospitalised patients. This study aimed to compare the mortality trends of patients with delirium according to the underlying physical condition.

METHODS

Hospitalised patients diagnosed with delirium by the Modena Consultation-Liaison Psychiatry Service (Italy) during 2020 were enrolled. Three groups were identified: COVID; after orthotopic liver transplant (OLT); other conditions. The full medical records were screened to retrieve socio-demographic and clinical data. INTERMED score and Delirium Rating Scale were used to retrospectively rate bio-social-complexity and delirium severity. Early (20 days) and end of study (31^st January 2021) mortality were ascertained for each subject.

RESULTS

A total of 103 patients were enrolled. Patients hospitalised for COVID showed higher INTERMED scores (two-tailed t-test, p = 0.019) and higher 20-day mortality (HR = 3.68, p = 0.014). When considering a 1-year follow-up, the main predictor of mortality was patients' age in all three subgroups (HR = 1.06; p = 0.003).

CONCLUSION

Our results suggest that patients hospitalised for COVID-19 with delirium showed higher bio-psycho-social complexity and higher short-term mortality, regardless of the severity of delirium. OLT patients showed lower mortality and bio-psycho-social complexity, despite being still considered as 'complex', according to the INTERMED score. Future research should focus on understanding the underlying mechanisms in the relationship between delirium and mortality.Key pointsPatients hospitalised for COVID-19 with delirium were found at risk of higher short-term mortality and higher bio-psycho-social complexity.OLT patients showed lower overall mortality and lower bio-psycho-social complexity than the other two groups, despite being still in the 'complex' range according to the INTERMED score.Future research should assess the areas of impact of delirium in patients affected by COVID-19, considering short- and long-term outcomes.

Automated machine learning-based model for the prediction of delirium in patients after surgery for degenerative spinal disease

OBJECTIVE

This study used machine learning algorithms to identify critical variables and predict postoperative delirium (POD) in patients with degenerative spinal disease.

METHODS

We included 663 patients who underwent surgery for degenerative spinal disease and received general anesthesia. The LASSO method was used to screen essential features associated with POD. Clinical characteristics, preoperative laboratory parameters, and intraoperative variables were reviewed and were used to construct nine machine learning models including a training set and validation set (80% of participants), and were then evaluated in the rest of the study sample (20% of participants). The area under the receiver-operating characteristic curve (AUROC) and Brier scores were used to compare the prediction performances of different models. The eXtreme Gradient Boosting algorithms (XGBOOST) model was used to predict POD. The SHapley Additive exPlanations (SHAP) package was used to interpret the XGBOOST model. Data of 49 patients were prospectively collected for model validation.

RESULTS

The XGBOOST model outperformed the other classifier models in the training set (area under the curve [AUC]: 92.8%, 95% confidence interval [CI]: 90.7%-95.0%), validation set (AUC: 87.0%, 95% CI: 80.7%-93.3%). This model also achieved the lowest Brier Score. Twelve vital variables, including age, serum albumin, the admission-to-surgery time interval, C-reactive protein level, hypertension, intraoperative blood loss, intraoperative minimum blood pressure, cardiovascular-cerebrovascular disease, smoking, alcohol consumption, pulmonary disease, and admission-intraoperative maximum blood pressure difference, were selected. The XGBOOST model performed well in the prospective cohort (accuracy: 85.71%).

CONCLUSION

A machine learning model and a web predictor for delirium after surgery for the degenerative spinal disease were successfully developed to demonstrate the extent of POD risk during the perioperative period, which could guide appropriate preventive measures for high-risk patients.

Delirium severity does not differ between medical and surgical intensive care units after adjusting for medication use

Severe delirium is associated with an increased risk of mortality, institutionalization, and length of stay. Few studies have examined differences in delirium severity between different populations of critically ill patients. The objective of the study was to compare delirium severity and the presence of the four core features between adults in the surgical intensive care unit (SICU) and medical intensive care unit (MICU) while controlling for variables known to be associated with delirium. This is a secondary analysis of two parallel randomized multi-center trials conducted from March 2009 to January 2015 at 3 Indianapolis hospitals. A total of 474 adults with delirium were included in the analysis. Subjects were randomized in a 1:1 ratio in random blocks of 4 by a computer program. Patients were randomized to either haloperidol prescribing or de-prescribing regimen vs usual care. Delirium severity was assessed daily or twice-daily using the CAM-ICU-7 beginning after 24 h of ICU admission and until discharge from the hospital, death, or 30 days after enrollment. Secondary outcomes included hospital length of stay, hospital and 30-day mortality, and delirium-related adverse events. These outcomes were compared between SICU and MICU settings for this secondary analysis. Out of 474 patients, 237 were randomized to intervention. At study enrollment, the overall cohort had a mean age of 59 (SD 16) years old, was 54% female, 44% African-American, and 81% were mechanically ventilated upon enrollment. MICU participants were significantly older and severely ill with a higher premorbid cognitive and physical dysfunction burden. In univariate analysis, SICU participants had significantly higher mean total CAM-ICU-7 scores, corresponding to delirium severity, (4.15 (2.20) vs 3.60 (2.32), p = 0.02), and a lower mean RASS score (- 1.79 (1.28) vs - 1.53 (1.27), p < 0.001) compared to MICU participants. Following adjustment for benzodiazepines and opioids, delirium severity did not significantly differ between groups. The presence of Feature 3, altered level of consciousness, was significantly associated with the SICU participants, identifying as Black, premorbid functional impairment, benzodiazepines, opioids, and dexmedetomidine. In this secondary analysis examining differences in delirium severity between MICU and SICU participants, we did not identify a difference between participant populations following adjustment for administered benzodiazepines and opioids. We did identify that an altered level of consciousness, core feature 3 of delirium, was associated with SICU setting, identifying as Black, activities of daily living, benzodiazepines and opioid medications. These results suggest that sedation practice patterns play a bigger role in delirium severity than the underlying physiologic insult, and expression of core features of delirium may vary based on individual factors.Trial registration CT#: NCT00842608.

The development of a web-based app employing machine learning for delirium prevention in long-term care facilities in South Korea

Background

Long-term care facilities (LCFs) in South Korea have limited knowledge of and capability to care for patients with delirium. They also often lack an electronic medical record system. These barriers hinder systematic approaches to delirium monitoring and intervention. Therefore, this study aims to develop a web-based app for delirium prevention in LCFs and analyse its feasibility and usability.

Methods

The app was developed based on the validity of the AI prediction model algorithm. A total of 173 participants were selected from LCFs to participate in a study to determine the predictive risk factors for delerium.

The app was developed in five phases: (1) the identification of risk factors and preventive intervention strategies from a review of evidence-based literature, (2) the iterative design of the app and components of delirium prevention, (3) the development of a delirium prediction algorithm and cloud platform, (4) a pilot test and validation conducted with 33 patients living in a LCF, and (5) an evaluation of the usability and feasibility of the app, completed by nurses (Main users).

Results

A web-based app was developed to predict high risk of delirium and apply preventive interventions accordingly. Moreover, its validity, usability, and feasibility were confirmed after app development. By employing machine learning, the app can predict the degree of delirium risk and issue a warning alarm. Therefore, it can be used to support clinical decision-making, help initiate the assessment of delirium, and assist in applying preventive interventions.

Conclusions

This web-based app is evidence-based and can be easily mobilised to support care for patients with delirium in LCFs. This app can improve the recognition of delirium and predict the degree of delirium risk, thereby helping develop initiatives for delirium prevention and providing interventions. Moreover, this app can be extended to predict various risk factors of LCF and apply preventive interventions. Its use can ultimately improve patient safety and quality of care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12911-022-01966-8.

Chlordiazepoxide-induced delirium in a patient undergoing alcohol withdrawal: a case report

Background

Ethanol dependence is associated with a discontinuation withdrawal delirium. Chlordiazepoxide is frequently successfully used in its treatment.

Case presentation

A 27-year-old, Caucasian female with ethanol dependence who had objective symptoms of withdrawal experienced worsening of her delirium after administration of chlordiazepoxide, but improved with lorazepam and cleared with discontinuation of benzodiazepine administration.

Conclusions

Worsening of delirium appears to be related to the specific use of chlordiazepoxide, but the mechanism of this effect is not clear. While this case does not alter the standard care of ethanol dependence, it does alert clinicians that our treatment approach may not be fully benign.

Investigation of Risk Factors for Postoperative Delirium after Transcatheter Aortic Valve Implantation: A Retrospective Study

Transcatheter aortic valve implantation (TAVI) is an effective treatment for severe aortic stenosis (AS); however, postoperative delirium (POD) can worsen patient outcomes. This study aimed to examine the risk factors for POD after TAVI, including possible intervening factors. We included 87 patients (mean age: 83) who underwent TAVI between May 2014 and September 2018. POD was defined by the presence or absence of delirium on ICU admission, assessed using the Confusion Assessment Method for the ICU. Factors that showed significant differences in the univariate analysis were analyzed using a multiple logistic regression analysis. In total, 31 patients (36%) had POD after ICU admission, and 56 (64%) did not. The preoperative frailty score and aortic valve opening area (AVA) were significant risk factors for POD. The multivariate analysis also showed that both factors were independent risk factors for POD (area under the receiver operating characteristic curve: 0.805). There were no significant differences in the number of ICU days. However, postoperative hospitalization was significantly longer in the POD group (19 (17–31) days vs. 16 (13–22) days; p = 0.002). POD was associated with a narrow AVA and frailty; this suggests that frailty prevention interventions according to the AVA may be important.

A systematic review of strategies for preventing delirium in patients undergoing vascular surgery

OBJECTIVES

Elderly patients undergoing vascular surgery are at risk of developing postoperative delirium, which is associated with a high mortality. Delirium prevention is difficult and is investigated in surgical patients from various specialisms, but little is known about delirium prevention in vascular surgery. For this reason we performed a systematic review on strategies for delirium prevention in patients undergoing elective surgery for peripheral arterial disease or for an aneurysm of the abdominal aorta.

METHODS

This systematic review included studies describing strategies for preventing delirium in patients undergoing elective surgery for peripheral arterial disease or for an aneurysm of the abdominal aorta. The search was conducted using the keywords 'vascular surgery', 'prevention' and 'delirium', and was last run on October 21st, 2021 in the electronic databases Pubmed, MEDLINE, Embase, Web of Science, the Cochrane library and Emcare. Risk of bias was assessed using the Cochrane Risk of Bias tool for randomized controlled trials and the ROBINS-1 tool for observational studies.

RESULTS

Four studies including 565 patients were included in the systematic review. A significant decrease in the incidence of delirium was reported by a study investigating the effect of comprehensive geriatric assessments within patients undergoing surgery for an aneurysm of the abdominal aorta or lower limb bypass surgery (24% in the control group versus 11% in the intervention group, p = 0.018), and in the total group of a study evaluating the effect of outpatient clinic multimodal prehabilitation for patients with an aneurysm of the abdominal aorta (11.7% in the control group versus 8.2% in the intervention group, p = 0.043, OR = 0.56). A non-significant decrease in delirium incidence was described for patients receiving a multidisciplinary quality improvement at the vascular surgical ward (21.4% in the control group versus 14.6% in the intervention group, p = 0.17). The study concerning the impact of the type of anaesthesia on delirium in eleven older vascular surgical patients, of which three developed delirium, did not differentiate between the different types of anaesthesia the patients received.

CONCLUSION

Despite the high and continuous increasing incidence of delirium in the growing elderly vascular population, little is known about effective preventive strategies. An approach to address multiple risk factors simultaneously seems to be promising in delirium prevention, whether through multimodal prehabilitation or comprehensive geriatric assessments. Several strategies including prehabilitation programs have been proven to be successful in other types of surgery and more research is required to evaluate effective preventive strategies and prehabilitation programs in vascular surgical patients.

Using a Standardized Rounding Tool to Improve the Incidence of Spontaneous Awakening and Breathing Trials

BACKGROUND

Spontaneous awakening and breathing trials have been associated with shorter durations of mechanical ventilation and intensive care unit lengths of stay.

LOCAL PROBLEM

Inconsistent spontaneous awakening trials and spontaneous breathing trials, mechanical ventilation weaning strategies, and interdisciplinary rounding processes contributed to prolonged mechanical ventilation duration and length of stay in a 44-bed adult medical intensive care unit. Methods A standardized rounding tool that focused on coordinating spontaneous awakening and breathing trials, and on their outcomes, was integrated into daily multidisciplinary rounds in a medical intensive care unit. Aggregated patient data from the 4-month project implementation phase were compared with historical data collected for 2 months before project implementation.

RESULTS

During the 2-month preintervention phase, 613 adult patients were managed in the medical intensive care unit and 41 patients required mechanical ventilation, whereas during the 4-month intervention phase, 1271 patients were managed in the unit and 96 patients required mechanical ventilation. The project was associated with a 24% (0.89-day) reduction in the mean length of stay (3.72 vs 2.83 days) and a 46.3% (2.81 day) reduction in mechanical ventilation duration (6.06 vs 3.25 days) when comparing August 2019 to January 2020.

DISCUSSION

A standardized rounding tool emphasizing a coordinated process for spontaneous awakening and breathing trials was associated with a shorter length of stay and duration of mechanical ventilation among patients in the medical intensive care unit.

CONCLUSION

An evidence-based approach to weaning from mechanical ventilation and standardized rounding may be a cost-effective way to reduce mechanical ventilation duration and length of stay in a medical intensive care unit.

A Case of Refractory Delirium Managed by a Multimodal Approach Using Atypical Antipsychotics, Antidepressants, and Benzodiazepines in an ICU Setting

Delirium is an acute confusional state, most commonly observed in elderly patients admitted to the critical care unit. In most cases, early recognition, avoiding triggering factors and conservative measures are adequate for the management, but sometimes symptoms persist despite adequate medical care, which goes in the favor of refractory delirium. Refractory delirium has no clear-cut definition but it is discussed in some of the case reports and literature as the presence of symptoms despite adequate treatment without impairing consciousness. Management of such refractory symptoms requires careful evaluation to identify the cause and predominant symptoms, which further helps in choosing a better therapeutic regime. It is often difficult to manage such cases and require sedatives and anti-psychotics to reverse the condition. Atypical antipsychotics are now playing a prominent role in the management of refractory delirium, and the selection of a drug that is suitable for the patient profile with negligible side effects is of utmost importance. We are presenting one such case, with multiple causes for his delirium, with a predominant hyperactive state and the refractory symptoms managed by atypical antipsychotics, antidepressants, and benzodiazepines.