Incidence and risk factors for delirium development in ICU patients - a prospective observational study

Former smoking, but not active smoking, is associated with delirium in postoperative ICU patients: a matched case-control study

Objective

To examine the relationship between current and former smoking and the occurrence of delirium in surgical Intensive Care Unit (ICU) patients.

Methods

We conducted a single center, case-control study involving 244 delirious and 251 non-delirious patients that were admitted to our ICU between 2018 and 2022. Using propensity score analysis, we obtained 115 pairs of delirious and non-delirious patients matched for age and Simplified Acute Physiology Score II (SAPS II). Both groups of patients were further stratified into non-smokers, active smokers and former smokers, and logistic regression was performed to further investigate potential confounders.

Results

Our study revealed a significant association between former smoking and the incidence of delirium in ICU patients, both in unmatched (adjusted odds ratio (OR): 1.82, 95% confidence interval (CI): 1.17-2.83) and matched cohorts (OR: 3.0, CI: 1.53-5.89). Active smoking did not demonstrate a significant difference in delirium incidence compared to non-smokers (unmatched OR = 0.98, CI: 0.62-1.53, matched OR = 1.05, CI: 0.55-2.0). Logistic regression analysis of the matched group confirmed former smoking as an independent risk factor for delirium, irrespective of other variables like surgical history (p = 0.010). Notably, also respiratory and vascular surgeries were associated with increased odds of delirium (respiratory: OR: 4.13, CI: 1.73-9.83; vascular: OR: 2.18, CI: 1.03-4.59). Medication analysis showed that while Ketamine and Midazolam usage did not significantly correlate with delirium, Morphine use was linked to a decreased likelihood (OR: 0.27, 95% CI: 0.13-0.55).

Discussion

Nicotine's complex neuropharmacological impact on the brain is still not fully understood, especially its short-term and long-term implications for critically ill patients. Although our retrospective study cannot establish causality, our findings suggest that smoking may induce structural changes in the brain, potentially heightening the risk of postoperative delirium. Intriguingly, this effect seems to be obscured in active smokers, potentially due to the recognized neuroprotective properties of nicotine. Our results motivate future prospective studies, the results of which hold the potential to substantially impact risk assessment procedures for surgeries.

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.

Risk factors, preventive interventions, overlapping symptoms, and clinical measures of delirium in elderly patients

Delirium is an acute reversible neuropsychiatric syndrome caused by multiple factors. It is associated with many adverse clinical outcomes including cognitive impairment, functional decline, prolonged hospitalization, and increased nursing service. The prevalence of delirium was high in department of cardiology, geriatric, and intensive care unit of hospital. With the increase in the aged population, further increases in delirium seem likely. However, it remains poorly recognized in the clinical practice. This article comprehensively discusses the latest research perspectives on the epidemiological data, risk factors, preventive interventions, overlapping symptoms, and clinical measures of delirium, including specific measures to manage delirium in clinical real-world situations. This article helps readers improve their knowledge and understanding of delirium and helps clinicians quickly identify and implement timely therapeutic measures to address various delirium subtypes that occur in the clinical settings to ensure patients are treated as aggressively as possible.

A randomized, clinical trial investigating the use of a digital intervention to reduce delirium-associated agitation

We aimed to determine if a novel digital therapeutic intervention could reduce agitation and unscheduled medication use in an adult delirious acute care population. Delirious participants were randomly allocated (1:1) to receive standard of care plus a single 4-hour exposure to the digital intervention "MindfulGarden", which uses a screen-based delivery to display a nature landscape with dynamic adjustment of screen content in response to movement and sound or standard of care only. Between March 2021 and January 2022, 73 participants were enrolled with 70 completing the trial protocol and included in the final analysis with a mean age of 61 years and 68% being male (35 intervention, 35 control). Mean RASS was significantly lower across the 4-hour study period in the intervention arm 0.3 (0.85) vs 0.9 (0.93), p = 0.01. Exposure to a nature-based dynamic digital intervention showed benefits in agitation reduction.

Orexin receptor antagonists versus antipsychotics for the management of delirium in intensive care unit patients with cardiovascular disease: A retrospective observational study

OBJECTIVE

Although antipsychotics are often used in the pharmacological treatment of delirium, recent reports suggest the efficacy of orexin receptor antagonists. This study investigated whether orexin receptor antagonists could be a possible treatment option for delirium.

METHOD

A nonblinded nonrandomized routine clinical treatment was performed. Patients treated in intensive care units (ICU) for cardiovascular disease and receiving psychiatric intervention were studied retrospectively. The scores from the Intensive Care Delirium Screening Checklist (ICDSC) were compared between patients treated with orexin receptor antagonists and those treated with antipsychotics.

RESULTS

The mean (standard deviation) ICDSC scores were 4.5 (1.8) at day -1 and 2.6 (2.6) at day 7 for orexin receptor antagonist group (n = 25) and 4.6 (2.4) at day -1 and 4.1 (2.2) at day 7 for antipsychotic group (n = 28). The orexin receptor antagonist group showed significantly lower ICDSC scores than the antipsychotic group (p = 0.021).

CONCLUSION

While precise efficacy cannot be determined from our retrospective, observational, and uncontrolled pilot study, this analysis encourages a future double-blind randomized placebo-controlled trial of orexin-antagonists for delirium treatment.

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.

S100B as a predictor of delirium in critically ill obstetric patients: A nested case-control study

Background

Delirium is a neuropsychiatric illness that lasts for a short period of time. The incidence of delirium in the intensive care unit (ICU) varies from 20% to 80%.

Methods

A nested case-control study was carried out in the obstetric ICU. Individuals were divided into three groups: critically ill obstetric women who had delirium on admission (Group A), women who developed delirium within follow-up of 7 days (Group B), and women who did not develop delirium after follow-up of 7 days (Group C). The APACHE II score was used to assess critical illness severity. The Richmond Agitation-Sedation Scale was used to assess the alertness or sedation level of patients, and the Confusion Assessment Method (ICU scale) was used to assess the presence of delirium. S100B was measured by human S100B calcium-binding protein B ELISA kit (Elabscience Biotechnology, Houston, USA).

Results

Severe preeclampsia and antepartum eclampsia were significantly associated with delirium. S100B levels in Group B were found to be significantly higher than those in Group C. S100B levels were higher in patients with >2 morbidities in comparison to patients with two morbidities. At a cutoff value of >169.25 pg/ml, S100B had a sensitivity of 74% and a specificity of 87.2% to discriminate cases of delirium from nondelirium.

Conclusion

The rise in S100B levels was approximately three times greater in those who developed delirium as compared to those who did not. It is a more specific predictor of delirium.

Calibration of the PREdiction of DELIRium in ICu Patients (PRE-DELIRIC) Score in a Cohort of Critically Ill Patients: A Retrospective Cohort Study

BACKGROUND

To predict delirium in intensive care unit (ICU) patients, the Prediction of Delirium in ICU Patients (PRE-DELIRIC) score may be used. This model may help nurses to predict delirium in high-risk ICU patients.

OBJECTIVES

The aims of this study were to externally validate the PRE-DELIRIC model and to identify predictive factors and outcomes for ICU delirium.

METHOD

All patients underwent delirium risk assessment by the PRE-DELIRIC model at admission. We used the Intensive Care Delirium Screening Check List to identify patients with delirium. The receiver operating characteristic curve measured discrimination capacity among patients with or without ICU delirium. Calibration ability was determined by slope and intercept.

RESULTS

The prevalence of ICU delirium was 55.8%. Discrimination capacity (Intensive Care Delirium Screening Check List score ≥4) expressed by the area under the receiver operating characteristic curve was 0.81 (95% confidence interval, 0.75-0.88), whereas sensitivity was 91.3% and specificity was 64.4%. The best cut-off was 27%, obtained by the max Youden index. Calibration of the model was adequate, with a slope of 1.03 and intercept of 8.14. The onset of ICU delirium was associated with an increase in ICU length of stay (P < .0001), higher ICU mortality (P = .008), increased duration of mechanical ventilation (P < .0001), and more prolonged respiratory weaning (P < .0001) compared with patients without delirium.

DISCUSSION

The PRE-DELIRIC score is a sensitive measure that may be useful in early detection of patients at high risk for developing delirium. The baseline PRE-DELIRIC score could be useful to trigger use of standardized protocols, including nonpharmacologic interventions.

Correlation of C-reactive Protein with Delirium in Obstetrics Intensive Care Unit: A Tertiary Center Experience

Background

Delirium is a neuropsychiatric illness. It affects critically ill patients on ventilator and increases mortality. The aim of this study was to evaluate the association of C-reactive protein (CRP) level with delirium in critically obstetrics women and its role in prediction of delirium.

Materials and methods

Arospective observational study was conducted in the intensive care unit (ICU), and the duration of study was one year. Total 145 subjects were recruited, 33 patients were excluded, and 112 subjects were studied. For study, group A (n = 36) includes critically ill obstetric women who had delirium on admission; group B (n = 37) includes critically ill obstetric women who developed delirium within 7 days; and group C (n = 39) that includes critically ill obstetric women who did not develop delirium after follow-up of 7 days was served as control. Disease severity was assessed by using acute physiologic assessment and chronic health evaluation (APACHE) II score, and Richmond Agitation-Sedation Scale (RASS) was used to assess awakeness. In awake patients (RASS of ≥3), delirium was assessed by the use of confusion assessment method for ICU tools. C-reactive protein measured by particle enhanced turbidimetric immunoassay-two point kinetic method.

Results

The mean ages of group A, B, and C were 26.44 ± 4.72, 27.46 ± 4.97, and 28.26 ± 5.67 years, respectively. C-reactive protein levels on the day of delirium development (group B) were found to be significantly higher than day 1 CRP levels of groups A and C. The mean Global Attentiveness Rating (GAR) was significantly lower in groups A and B as compared to that in group C (p < 0.001). On evaluating the correlation of CRP with GAR, it was found to be inverse and mild in strength for the correlation between CRP and GAR (r = -0.403, p < 0.001). At a cut-off value of >181 mg/L, CRP had sensitivity of 93.2% and specificity of 69.2%. The positive predictive value was 85% and the negative predictive value was 84.4% that differentiate delirium from non-delirium.

Conclusion

C-reactive protein is a useful tool for screening and prediction of delirium in critically ill obstetric patients.

How to cite this article

Shyam R, Patel ML, Solanki M, Sachan R, Ali W. Correlation of C-reactive Protein with Delirium in Obstetrics Intensive Care Unit: A Tertiary Center Experience. Indian J Crit Care Med 2023;27(5):315-321.

Predisposing and Precipitating Factors Associated With Delirium: A Systematic Review

IMPORTANCE

Despite discrete etiologies leading to delirium, it is treated as a common end point in hospital and in clinical trials, and delirium research may be hampered by the attempt to treat all instances of delirium similarly, leaving delirium management as an unmet need. An individualized approach based on unique patterns of delirium pathophysiology, as reflected in predisposing factors and precipitants, may be necessary, but there exists no accepted method of grouping delirium into distinct etiologic subgroups.

OBJECTIVE

To conduct a systematic review to identify potential predisposing and precipitating factors associated with delirium in adult patients agnostic to setting.

EVIDENCE REVIEW

A literature search was performed of PubMed, Embase, Web of Science, and PsycINFO from database inception to December 2021 using search Medical Subject Headings (MeSH) terms consciousness disorders, confusion, causality, and disease susceptibility, with constraints of cohort or case-control studies. Two reviewers selected studies that met the following criteria for inclusion: published in English, prospective cohort or case-control study, at least 50 participants, delirium assessment in person by a physician or trained research personnel using a reference standard, and results including a multivariable model to identify independent factors associated with delirium.

FINDINGS

A total of 315 studies were included with a mean (SD) Newcastle-Ottawa Scale score of 8.3 (0.8) out of 9. Across 101 144 patients (50 006 [50.0%] male and 49 766 [49.1%] female patients) represented (24 015 with delirium), studies reported 33 predisposing and 112 precipitating factors associated with delirium. There was a diversity of factors associated with delirium, with substantial physiological heterogeneity.

CONCLUSIONS AND RELEVANCE

In this systematic review, a comprehensive list of potential predisposing and precipitating factors associated with delirium was found across all clinical settings. These findings may be used to inform more precise study of delirium's heterogeneous pathophysiology and treatment.

Risk Factors for Delirium Superimposed on Dementia in Elderly Patients in Comprehensive Ward

OBJECTIVE

To investigate the incidence of delirium and its related risk factors in patients with senile dementia during hospitalization.

METHODS

A retrospective analysis of clinical data of 157 patients over 65 with cognitive impairment who were hospitalized in the comprehensive ward from October 2019 to February 2023 was conducted. Patients were assigned into delirium and non-delirium groups according to whether they exhibited delirium during hospitalization. General information about the patients and Visual Analogue Scale (VAS) score, blood C-reactive protein level, and blood superoxide dismutase (SOD) level were recorded. Univariate analysis was used to identify potential risk factors for delirium, and factors with statistical significance were subjected to multivariate logistic regression analysis. A prediction line chart for delirium in elderly dementia patients was constructed using R 4.03 software, and the model was validated.

RESULTS

Among the 157 patients with senile dementia, 42 patients exhibited delirium and 115 patients exhibited non-delirium. Multivariate logistic regression analysis showed that diabetes, cerebrovascular disease, VAS score ≥4 points, use of sedative drugs, and blood SOD <129 U/mL were independent risk factors for delirium during hospitalization in elderly dementia patients. A prediction nomogram was plotted based on the five risk factors, and receiver operating characteristic curve analysis presented an area under the curve of .875 (95% CI: .816-.934). The nomogram model was internally validated by the Bootstrap method, and the calibration curve showed good agreement between predicted and actual results. Hosmer-Lemeshow test demonstrated that the model had a good fit and high predictive ability.

CONCLUSION

Diabetes, cerebrovascular disease, VAS ≥4 points, use of sedative drugs, and blood SOD <129 U/mL were independent risk factors for delirium in patients with senile dementia during hospitalization. The nomogram model had good accuracy and clinical application value for predicting delirium in this study.

Research progress on risk factors of delirium in burn patients: A narrative review

Delirium, an acute brain dysfunction, is a common and serious complication in burn patients. The occurrence of delirium increases the difficulty of patient treatment, is associated with various adverse outcomes, and increases the burden on the patient's family. Many scholars have studied the factors that cause delirium, but the causes, pathogenesis, and treatment of delirium in burn patients have not been fully revealed. There is no effective pharmacological treatment for delirium, but active preventive measures can effectively reduce the incidence of delirium in burn patients. Therefore, it is necessary to study the relevant factors affecting the occurrence of delirium in burn patients. This study was conducted on December 20, 2021 by searching the PubMed database for a narrative review of published studies. The search strategy included keywords related to "burns," "delirium," and "risk factors." We reviewed the characteristics of delirium occurrence in burn patients and various delirium assessment tools, and summarized the risk factors for the development of delirium in burn patients in terms of personal, clinical, and environmental factors, and we found that although many risk factors act on the development of delirium in burn patients, some of them, such as clinical and environmental factors, are modifiable, suggesting that we can estimate the exposure of burn patients to risk factors by assessing their likelihood of delirium occurring and to make targeted interventions that provide a theoretical basis for the prevention and treatment of burn delirium.

Incidence, Associated Factors, and Outcome of Delirium among Patients Admitted to ICUs in Oman

Background

The incidence of delirium is high up to 46.3% among patients admitted to ICU. Delirium is linked to negative patient outcomes like increased duration of mechanical ventilation use, prolonged ICU stay, increased mortality rate, and healthcare costs. Despite the importance of delirium and its consequences that are significant, there is a scarcity of studies which explored delirium in Oman.

Objectives

This study was conducted to assess the incidence of delirium, the association between the selected predisposing factors and precipitating factors with delirium, determine the predicators of delirium, and evaluate its impacts on ICU mortality and ICU length of stay among ICU patients in Oman.

Methods

A multicenter prospective observational design was used. A total of 153 patients were assessed two-times a day by bedside ICU nurses through the Intensive Care Delirium Screening Checklist (ICDSC).

Results

The results revealed that the delirium incidence was 26.1%. Regression analysis showed that sepsis, metabolic acidosis, nasogastric tube use, and APACHE II score were independent predictors for delirium among ICU patients in Oman and delirium had significant impacts on ICU length of stay and mortality rate.

Conclusion

Delirium is common among ICU patients and it is associated with negative consequences. Multidisciplinary prevention strategies should be implemented to identify and treat the modifiable risk factors.

Pneumonia in Nervous System Injuries: An Analytic Review of Literature and Recommendations

Pneumonia is one of the most common complications in intensive care units and is the most common nosocomial infection in this setting. Patients with neurocritical conditions who are admitted to ICUs are no exception, and in fact, are more prone to infections such as pneumonia because of factors such as swallow dysfunction, need for mechanical ventilation, longer length of stay in hospitals, etc. Common central nervous system pathologies such as ischemic stroke, traumatic brain injury, subarachnoid hemorrhage, intracerebral hemorrhage, neuromuscular disorders, status epilepticus, and demyelinating diseases can cause long in-hospital admissions and increase the risk of pneumonia each with a mechanism of its own. Brain injury-induced immunosuppression syndrome is usually considered the common mechanism through which patients with critical central nervous system conditions become susceptible to different kinds of infection including pneumonia. Evaluating the patients and assessment of the risk factors can lead our attention toward better infection control in this population and therefore decrease the risk of infections in central nervous system injuries.

Natural language processing diagnosed behavioral disturbance vs confusion assessment method for the intensive care unit: prevalence, patient characteristics, overlap, and association with treatment and outcome

PURPOSE

To compare the prevalence, characteristics, drug treatment for delirium, and outcomes of patients with Natural Language Processing (NLP) diagnosed behavioral disturbance (NLP-Dx-BD) vs Confusion Assessment Method for intensive care unit (CAM-ICU) positivity.

METHODS

In three combined medical-surgical ICUs, we obtained data on demographics, treatment with antipsychotic medications, and outcomes. We applied NLP to caregiver progress notes to diagnose behavioral disturbance and analyzed simultaneous CAM-ICU.

RESULTS

We assessed 2313 patients with a median lowest Richmond Agitation-Sedation Scale (RASS) score of - 2 (- 4.0 to - 1.0) and median highest RASS score of 1 (0 to 1). Overall, 1246 (53.9%) patients were NLP-Dx-BD positive (NLP-Dx-BDpos) and 578 (25%) were CAM-ICU positive (CAM-ICUpos). Among NLP-Dx-BDpos patients, 539 (43.3%) were also CAM-ICUpos. In contrast, among CAM-ICUpos patients, 539 (93.3%) were also NLP-Dx-BDpos. The use of antipsychotic medications was highest in patients in the CAM-ICUpos and NLP-Dx-BDpos group (24.3%) followed by the CAM-ICUneg and NLP-Dx-BDpos group (10.5%). In NLP-Dx-BDneg patients, antipsychotic medication use was lower at 5.1% for CAM-ICUpos and NLP-Dx-BDneg patients and 2.3% for CAM-ICUneg and NLP-Dx-BDneg patients (overall P < 0.001). Regardless of CAM-ICU status, after adjustment and on time-dependent Cox modelling, NLP-Dx-BD was associated with greater antipsychotic medication use. Finally, regardless of CAM-ICU status, NLP-Dx-BDpos patients had longer duration of ICU and hospital stay and greater hospital mortality (all P < 0.001).

CONCLUSION

More patients were NLP-Dx-BD positive than CAM-ICU positive. NLP-Dx-BD and CAM-ICU assessment describe partly overlapping populations. However, NLP-Dx-BD identifies more patients likely to receive antipsychotic medications. In the absence of NLP-Dx-BD, treatment with antipsychotic medications is rare.

Nomogram Models for Predicting Delirium of Patients in Emergency Intensive Care Unit: A Retrospective Cohort Study

Background

Intensive care unit (ICU) delirium is one of the most common clinical syndromes that results in many adverse events that affect patients, families, and hospitals. To date, there has been no tool for effectively predicting the occurrence of delirium in emergency intensive care unit (EICU) patients.

Methods

We conducted a retrospective cohort study and constructed a prediction model for 319 patients in EICU, who met our inclusion criteria. We analyzed the relationship between patients’ clinical data within 24 hours of admission and delirium, applied univariate and multivariate logistic regression analyses to select the most relevant variables for construction of nomogram models, then applied bootstrapping for internal validation.

Results

A total of five variables, namely stomach and urinary tubes, as well as sedative, mechanical ventilation and APACHE-II scores, were selected for model construction. We generated a total of five sets of models (three sets of construction models and two sets of internal verification models), with similar predictive value. The optimal model was selected, and together with the 5 variables used to construct a nomogram. The AUC of the MFP model in all patients was 0.76 (0.70, 0.82), whereas that in non-elderly patients (<60 years old) for the full model was 0.83 (0.74, 0.91). In elderly patients (≥60 years old), the AUC of the MFP model was 0.82 (0.73, 0.91).

Conclusion

Overall, the five-marker-based prognostic tool, established herein, can effectively predict the occurrence of delirium in EICU patients.

Current status of delirium assessment tools in the intensive care unit: a prospective multicenter observational survey

Delirium is a critical challenge in the intensive care unit (ICU) or high care unit (HCU) setting and is associated with poor outcomes. There is not much literature on how many patients in this setting are assessed for delirium and what tools are used. This study investigated the status of delirium assessment tools of patients in the ICU/HCU. We conducted a multicenter prospective observational study among 20 institutions. Data for patients who were admitted to and discharged from the ICU/HCU during a 1-month study period were collected from each institution using a survey sheet. The primary outcome was the usage rate of delirium assessment tools on an institution- and patient-basis. Secondary outcomes were the delirium prevalence assessed by each institution’s assessment tool, comparison of delirium prevalence between delirium assessment tools, delirium prevalence at the end of ICH/HCU stay, and the relationship between potential factors related to delirium and the development of delirium. Result showed that 95% of institutions used the Intensive Care Delirium Screening Checklist (ICDSC) or the Confusion Assessment Method for the ICU (CAM-ICU) to assess delirium in their ICU/HCU, and the remaining one used another assessment scale. The usage rate (at least once during the ICU/HCU stay) of the ICDSC and the CAM-ICU among individual patients were 64.5% and 25.1%, and only 8.2% of enrolled patients were not assessed by any delirium assessment tool. The prevalence of delirium during ICU/HCU stay was 17.9%, and the prevalence of delirium at the end of the ICU/HCU stay was 5.9%. In conclusion, all institutions used delirium assessment tools in the ICU/HCU, and most patients received delirium assessment. The prevalence of delirium was 17.9%, and two-thirds of patients had recovered at discharge from ICU/HCU.

Trial registration number: UMIN000037834.

Point prevalence of delirium among critically ill patients in Saudi Arabia: A multicenter observational study

Background:

Delirium in critically ill patients is independently associated with poor clinical outcomes. There is a scarcity of published data on the prevalence of delirium among critically ill patients in Saudi Arabia. Therefore, we sought to determine, in a multicenter fashion, the prevalence of delirium in critically ill patients in Saudi Arabia and explore associated risk factors.

Methods:

A cross-sectional point prevalence study was conducted on January 28, 2020, at 14 intensive care units (ICUs) across 3 universities and 11 other tertiary care hospitals in Saudi Arabia. Delirium was screened once using the Intensive Care Delirium Screening Checklist. We excluded patients who were unable to participate in a valid delirium assessment, patients admitted with traumatic brain injury, and patients with documented dementia in their medical charts.

Results:

Of the 407 screened ICU patients, 233 patients were enrolled and 45.9% were diagnosed with delirium. The prevalence was higher in mechanically ventilated patients compared to patients not mechanically ventilated (57.5% vs. 33.6%; P < 0.001). In a multivariate model, risk factors independently associated with delirium included age (adjusted odds ratio [AOR], 1.021; 95% confidence interval [CI], 1.01–1.04; P = 0.008), mechanical ventilation (AOR, 2.39; 95% CI, 1.34–4.28; P = 0.003), and higher severity of illness (AOR, 1.01; 95% CI, 1.001–1.021; P = 0.026).

Conclusion:

In our study, delirium remains a prevalent complication, with distinct risk factors. Further studies are necessary to investigate long-term outcomes of delirium in critically ill patients in Saudi Arabia.

Delirium in Critically Ill Cancer Patients With COVID-19

BACKGROUND

COVID-19 has been a devastating pandemic with little known of its neuropsychiatric complications. Delirium is one of the most common neuropsychiatric syndromes among hospitalized cancer patients with incidence ranging from 25% to 40% and rates of up to 85% in the terminally ill. Data on the incidence, risk factors, duration, and outcomes of delirium in critically ill cancer patients with COVID-19 are lacking.

OBJECTIVE

To report the incidence, risks and outcomes of critically ill cancer patients who developed COVID-19.

METHODS

This is a retrospective single-center study evaluating delirium frequency and outcomes in all critically ill cancer patients with COVID-19 admitted between March 1 and July 10, 2020. Delirium was assessed by Confusion Assessment Method for Intensive Care Unit, performed twice daily by trained intensive care unit (ICU) nursing staff. Patients were considered to have a delirium-positive day if Confusion Assessment Method for Intensive Care Unit was positive at least once per day.

RESULTS

A total of 70 patients were evaluated. Of those 70, 53 (75.7%) were found to be positive for delirium. Patients with delirium were significantly older than patients without delirium (median age 67.5 vs 60.3 y, P = 0.013). There were no significant differences in demographic characteristics, chronic medical conditions, neuropsychiatric history, cancer type, or application of prone positioning between the 2 groups. Delirium patients were less likely to receive cancer-directed therapies (58.5% vs 88.2%, P = 0.038) but more likely to receive antipsychotics (81.1% vs 41.2%, P = 0.004), dexmedetomidine (79.3% vs 11.8%, P < 0.001), steroids (84.9% vs 58.8%, P = 0.039), and vasopressors (90.6% vs 58.8%, P = 0.006). Delirium patients were more likely to be intubated (86.8% vs 41.2%, P < 0.001), and all tracheostomies (35.9%) occurred in patients with delirium. ICU length of stay (19 vs 8 d, P < 0.001) and hospital length of stay (37 vs 12 d, P < 0.001) were significantly longer in delirium patients, but there was no statistically significant difference in hospital mortality (43.4% vs 58.8%, P = 0.403) or ICU mortality (34.0% vs 58.8%, P = 0.090).

CONCLUSIONS

Delirium in critically ill cancer patients with COVID-19 was associated with less cancer-directed therapies and increased hospital and ICU length of stay. However, the presence of delirium was not associated with an increase in hospital or ICU mortality.

Occurrence and Long-term Prognosis of Insomnia Disorder among Survivors of Acute Respiratory Distress Syndrome in South Korea

RATIONALE

As a most common type of sleep disorder, insomnia disorder can develop as a sequela among acute respiratory distress syndrome (ARDS) survivors. However, insomnia prevalence, its associated factors, and its impact on long-term survival remain controversial.

OBJECTIVES

This study aimed to investigate insomnia prevalence and its associated factors among ARDS survivors. We also examined the association between insomnia and 2-year all-cause mortality.

METHODS

The National Health Insurance Database of South Korea was used for this nationwide cohort study. We included adult patients (≥18 years old) admitted to intensive care units for ARDS treatment from January 1, 2010, to December 31, 2018, and survived for ≥1 year after diagnosis, defined as ARDS survivors. ARDS survivors diagnosed with insomnia disorder before ARDS diagnosis were defined as the pre-ARDS insomnia disorder group, whereas those who had no history of insomnia disorder but were newly diagnosed with insomnia disorder within 1 year of diagnosis of ARDS were defined as the post-ARDS insomnia disorder group.

RESULTS

A total of 4,452 ARDS survivors were included in this study, with 895 patients (20.1%) in the pre-ARDS insomnia disorder group and 536 (12.6%) patients in the post-ARDS insomnia disorder group. In the multivariable logistic regression analysis, delirium occurrence (odds ratio [OR]:1.61, 95% confidence interval [CI]: 1.24-2.10; P<0.001), underlying anxiety disorder (OR:1.34, 95% CI: 1.08-1.66; P=0.007), depression (OR: 1.48, 95% CI: 1.17-1.86; P=0.001), and substance abuse (OR:1.51, 95% CI: 1.01-2.26; P=0.042) were associated with a higher prevalence of post-ARDS insomnia disorder. In multivariable Cox regression analysis, the pre-ARDS insomnia disorder and post-ARDS insomnia disorder groups were associated with 1.33-fold (hazard ratio [HR]:1.33, 95% CI: 1.08-1.64; P=0.007) and 1.36-fold (HR:1.36, 95% CI: 1.06-1.74; P=0.016) increased prevalence of 2-year all-cause mortality among ARDS survivors, respectively.

CONCLUSIONS

At 1 year after diagnosis of ARDS, 12.6% of ARDS survivors were newly diagnosed with insomnia disorder in South Korea. Delirium and underlying psychiatric illness (anxiety disorder, depression, and substance abuse) were potential risk factors for the diagnosis of post-ARDS insomnia disorder. Moreover, both pre-and post-ARDS insomnia disorders were associated with 2-year all-cause mortality among ARDS survivors.

Diagnosis and Risk Factors for Delirium in Elderly Patients in the Emergency Rooms and Intensive Care Unit of the National Geriatric Hospital Emergency Department: A Cross-Sectional Observational Study

Purpose

To diagnose delirium and identify risk factors for its development in elderly patients in the emergency department (ED) and intensive care units (ICU) at the National Geriatric Hospital (Vietnam).

Patients and Methods

A cross-sectional observational study was conducted with a convenience sample of non-surgical patients admitted to ED and ICU at Hanoi National Geriatric Hospital in Vietnam. In total, 163 patients met the selection criteria and were included in the study. Screening involved using the Confusion Assessment Method (CAM) and the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU). The diagnosis was established according to the DSM-5 and ICD-10 codes.

Results

Delirium was found in a total of 106 (63.1%) patients. The factors significantly affecting its development were vision impairment (OR, 3.3; 95% CI, 1.5 to 7.4, P=0.003), hearing impairment (OR, 3.6; 95% CI, 1.77 to 7.36, P=0.0001), acute or chronic kidney failure (OR, 7.1; 95% CI, 2.05 to 6.39, P<0.001), respiratory disorders (OR, 2.7; 95% CI, 1.4 to 5.2, P=0.004), and malnutrition (OR, 9.17; 95% CI, 3.43–24.5, P=0.0001). The list also include the fall risk factors (OR, 12.2; 95% CI, 4.1–36.3, P=0.0001), frailty (OR, 8.35; 95% CI, 3.4–20.6, P=0.0001), activities of daily living (OR, 8.35; 95% CI, 3.4–20.6, P=0.0001), hyponatremia (OR, 2.48; 95% CI, 1.07 to 5.75, P=0.001), hypernatremia (OR, 13.1; 95% CI, 1.67 to 2.5, P=0.001), and treatment interventions. In addition, delirium was linked to the duration of ICU admission (OR, 6.53; 95% CI, 4.5–25.5, P < 0.0001).

Conclusion

The CAM/CAM-ICU diagnostic algorithm makes it possible to diagnose delirium successfully. The present study confirmed the role of several premorbid and triggering factors in the occurrence of delirium in elderly patients in ED and ICU. There is a need for further research into risk factors for delirium in elderly patients.

Development and Testing of an Algorithm to Prevent Medical Device-Related Pressure Injuries

We developed and tested the effectiveness of an algorithm to prevent medical device–related pressure injuries in intensive care unit patients. It was developed in four stages: literature review and analysis of medical records; preliminary algorithm development; validation of the preliminary algorithm by experts in two rounds; and practical feasibility verification of the revised algorithm by 109 intensive care unit nurses. To verify the algorithm’s effectiveness, we compared the incidence of medical device–related pressure injuries between 324 patients without algorithm application (control group) and 312 patients with algorithm application (experimental group). The outcomes were skin inspection of the medical device attachment, pressure injury evaluation, and implementation of pressure injury-preventive nursing care, based on the medical device type. The incidence rates were 1.46 per 100 devices (control group) and 1.19 per 100 devices (experimental group). Since there was no homogeneity in the previous score of the Braden scale in the experimental and control groups, the results regarding the incidence of pressure damage after applying the algorithm should be interpreted with care. Applying this algorithm was a safe intervention that helped prevent medical device–related pressure injuries in this population.

The assessment of risk factors for postoperative delirium using cubic spline curves in gastroenterological surgery

PURPOSE

Delirium is associated with longer hospital stays and increased medical costs and mortality. This study explored the risk factors for postoperative delirium in gastroenterological surgery and investigated the association between qualitative changes in risk factors and the incidence of postoperative delirium.

METHODS

A total of 418 patients > 18 years old who underwent gastroenterological surgery at our department between April 2018 and September 2019 were included. Risk factors were identified by comparing patients with and without postoperative delirium. Continuous variables were evaluated graphically using cubic spline curves. A logistic regression analysis was performed to assess independent risk factors.

RESULTS

The incidence of postoperative delirium was 6.9%. The cubic spline curve showed that the incidence of postoperative delirium began to increase at 50 years old and increased sharply at 70 years old. A multiple logistic regression analysis of patients > 50 years old identified 5 risk factors: age ≥ 70 years, preoperative serum albumin ≤ 3.8 g/dL, psychosis, sedative-hypnotics, and intensive-care unit admission.

CONCLUSION

The risk of postoperative delirium increases progressively at 50 years old and sharply at 70 years old. Advanced age, preoperative hypoalbuminemia, psychosis, sedative-hypnotics, and intensive-care unit admission are risk factors for postoperative delirium in patients > 50 years old undergoing gastroenterological surgery.

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.

Incidence of delirium in the critical care unit and risk factors in the Central Region, Saudi Arabia

Objectives:

To determine the incidence and risk factors of delirium in the cardiac care unit (CCU) and intensive care unit (ICU).

Methods:

This multicenter prospective observational study was conducted between July 2019 and November 2019 in the central region of Saudi Arabia. All patients admitted to the critical care units were enrolled, and their demographic data and risk factors of delirium were reported.

Results:

A total of 165 patients were included: 76 (46.1%) admitted to the CCU and 89 (53.9%) admitted to the ICU. The mean age was 55.1±18 years, and 45 (27.3%) were women. We found that 24/165 (14.5%) patients developed delirium during admission. Importantly, variables significantly associated with delirium group were female gender: (24.5% versus 10.8%, p=0.028), malnutrition (29.2% versus 5%, p<0.001), the presence of urinary catheter (75% versus 30.5%, p=0.001), septicemia (50% versus 14.9%, p<0.001), intubation (41.7% versus 10.6%, p=0.001), low hemoglobin (10.79±2.91 versus 12.05±2.77, p=048), and prolonged prothrombin time (PT) (15.87±5.17 versus 13.60±3.28, p=0.011).

Conclusion:

The incidence of delirium was 14.5% among patients admitted to critical care units in the central region of Saudi Arabia. Septicemia, prolonged PT, malnutrition, and urinary catheter are significant predictors of delirium.

Ensuring communication access for all during the COVID-19 pandemic and beyond: supporting patients, providers, and caregivers in hospitals

The COVID-19 pandemic has revealed substantial gaps in communication access for patients across hospital settings. With the rise in positive cases globally, the need for communication enhancement strategies, including augmentative and alternative communication (AAC), has emerged as a critical need. Many resources exist that describe AAC assessment and intervention processes in the acute care setting; however, AAC service provision in the COVID-19 pandemic is fraught with many unanticipated challenges. Patients, providers, and caregivers have encountered significant communication strain both at the bedside and beyond hospital walls, resulting in a communication crisis induced by many COVID-19 related variables. This article describes the sequelae of symptoms a person with COVID-19 may experience, progression of communication needs, and evidence-based solutions to supporting communication access. Barriers related to the COVID-19 pandemic are outlined (e.g., evolving infection control practices, personal protective equipment requirements, visitor policies, and more) along with response recommendations to support communication enhancement efforts for people with and without COVID-19 benefiting from access to AAC.

Added value of anxiolytic benzodiazepines in predictive models on severe delirium in patients with acute decompensated heart failure: A retrospective analysis

Background

Delirium in patients with acute decompensated heart failure (ADHF) is associated with poor clinical outcomes. Although some medications have been reported as risk factors for delirium, their impact on patients with ADHF is still unclear. This study aimed to determine the association of specific medication use with delirium and their additive predictive value in models based on conventional risk factors.

Methods and results

In this single-center, retrospective study, 650 patients treated for ADHF were included. Fifty-nine patients (9.1%) had delirium. In multivariate analysis, anxiolytic benzodiazepines [odds ratio (OR): 6.4, 95% confidence interval (CI): 2.8–15], mechanical ventilation or noninvasive positive pressure ventilation (OR: 6.0, 95% CI: 2.9–12), depression (OR: 3.2, 95% CI: 1.5–6.5), intensive care or high care unit admission (OR: 2.9, 95% CI: 1.5–5.6), male sex (OR: 2.0, 95% CI: 1–3.7), and age (OR: 1.1, 95% CI: 1–1.1) were independently associated with severe delirium. The predictive model that included anxiolytic benzodiazepines had a significantly better discriminatory ability for the incidence of severe delirium than the conventional model.

Conclusions

The use of anxiolytic benzodiazepines was independently correlated with severe delirium, and their use in models based on conventional risk factors had an additive value for predicting delirium in patients with ADHF.

Delirium in trauma patients: a 1-year prospective cohort study of 2026 patients

Background

Delirium in trauma surgery is common, especially post-operatively, but medical characteristics, risk factors and residence post-discharge have not comprehensively been investigated in all trauma patients.

Methods

Over 1 year, 2026 trauma patients were prospectively screened for delirium with the following tools: Delirium Observation screening scale (DOS), Intensive Care Delirium Screening Checklist (ICDSC) and a DSM (Diagnostic and Statistical Manual)-5, nursing tool (ePA-AC) construct. Risk factors—predisposing und precipitating—for delirium were assessed via multiple regression analysis.

Results

Of 2026 trauma patients, 440 (21.7%) developed delirium, which was associated with an increased risk of assisted living (OR 6.42, CI 3.92–10.49), transfer to nursing home (OR 4.66, CI 3.29–6.6), rehabilitation (OR 3.96, CI 3.1–5.1), or death (OR 70.72, CI 22–227.64). Intensive care management (OR 18.62, CI 14.04–24.68), requirement of ventilation (OR 32.21, CI 21.27–48.78), or its duration (OR 67.22, CI 33.8–133.71) all increased the risk for developing delirium. Relevant predisposing risk factors were dementia (OR 50.92, CI 15.12–171.45), cardiac insufficiency (OR 11.76, CI 3.6–38.36), and polypharmacy (OR 5.9, CI 4.01–8.68).Relevant precipitating risk factors were brain edema (OR 40.53, CI 4.81–341.31), pneumonia (OR 39.66, CI 8.89–176.93) and cerebral inflammation (OR 21.74, CI 2.34–202.07).

Conclusion

Delirium in trauma patients is associated with poor outcome as well as with intensive care management and various predisposing and/or precipitating factors. Three quarters of patients who had undergone delirium were not able to live independently at home any more.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00068-021-01603-5.

ICU Delirium-Prediction Models: A Systematic Review

Supplemental Digital Content is available in the text.

Objective:

Summarize performance and development of ICU delirium-prediction models published within the past 5 years.

Data Sources:

Systematic electronic searches were conducted in April 2019 using PubMed, Embase, Cochrane Central, Web of Science, and Cumulative Index to Nursing and Allied Health Literature to identify peer-reviewed studies.

Study Selection:

Eligible studies were published in English during the past 5 years that specifically addressed the development, validation, or recalibration of delirium-prediction models in adult ICU populations.

Data Extraction:

Screened citations were extracted independently by three investigators with a 42% overlap to verify consistency using the CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies.

Data Synthesis:

Eighteen studies featuring 23 distinct prediction models were included. Model performance varied greatly, as assessed by area under the receiver operating characteristic curve (0.62–0.94), specificity (0.50–0.97), and sensitivity (0.45–0.96). Most models used data collected from a single time point or window to predict the occurrence of delirium at any point during hospital or ICU admission, and lacked mechanisms for providing pragmatic, actionable predictions to clinicians.

Conclusions:

Although most ICU delirium-prediction models have relatively good performance, they have limited applicability to clinical practice. Most models were static, making predictions based on data collected at a single time-point, failing to account for fluctuating conditions during ICU admission. Further research is needed to create clinically relevant dynamic delirium-prediction models that can adapt to changes in individual patient physiology over time and deliver actionable predictions to clinicians.

New Cutoff Scores for Delirium Screening Tools to Predict Patient Mortality

BACKGROUND/OBJECTIVES

Detecting delirium is important to identify patients with a high risk of poor outcomes. Although many different kinds of screening instruments for delirium exist, there is no solid consensus about which methods are the most effective. In addition, it is important to find the most useful tools in predicting outcomes such as mortality.

DESIGN

Retrospective cohort study.

SETTING

University of Iowa Hospitals and Clinics.

PARTICIPANTS

A total of 1,125 adult inpatients (mean age = 67.7; median age = 69).

MEASUREMENTS

Post hoc analyses were performed based on existing data from the Confusion Assessment Method for Intensive Care Unit (CAM-ICU), Delirium Rating Scale-Revised-98 (DRS), and the Delirium Observation Screening Scale (DOSS). Correlation among these scales and relationships between 365-day mortality and each scale were evaluated.

RESULTS

A positive result on the CAM-ICU ("CAM-ICU positive") was associated with higher DRS and DOSS scores. A DRS score = 9/10 was the best cutoff to detect CAM-ICU positive, and DOSS = 2/3 was the best cutoff to detect CAM-ICU positive. CAM-ICU positive was associated with high 365-day mortality. DRS score = 9/10 and DOSS score = 0/1 were found to differentiate mortality risk the most significantly. Higher DRS and DOSS scores significantly coincided with a decrease in a patient's survival rate at 365 days.

CONCLUSION

The best DRS and DOSS cutoff scores to differentiate 365-day mortality risk were lower than those commonly used to detect delirium in the literature. New cutoff scores for the DRS and DOSS might be useful in differentiating risk of mortality among hospital patients.

Suvorexant for the prevention of delirium: A meta-analysis

BACKGROUND

Delirium is a frequently encountered complication, which is associated with increased mortality. Suvorexant, an approved agent for the treatment of insomnia, is recently suggested to be also effective for prevention of delirium by some authors. However, a consensus has yet to be reached. The goal of this study was to perform a meta-analysis to overall estimate the effectiveness of suvorexant in preventing delirium and its related consequences.

METHODS

Eligible studies were identified by searching online databases of PubMed, EMBASE, and Cochrane Library. The pooled OR was calculated for binary outcomes (e.g., the incidence of delirium, mortality, or adverse events), while standardized mean difference (SMD) were expressed for continuous outcomes (e.g., time to delirium onset, length of stay in hospital and ICU, time on ventilation).

RESULTS

Seven studies which comprised 402 suvorexant treatment patients and 487 patients with control treatment were included in this meta-analysis. Overall, pooled analysis indicated the incidence of delirium could be significantly reduced (OR, 0.30; P < .001) and time to delirium onset was significantly lengthened (SMD, 0.44; P = .006) in patients undergoing suvorexant treatment compared with controls. Suvorexant had no beneficial effects on the secondary outcomes [length of stay in hospital (SMD, -0.65; P = .161) and ICU (SMD, 0.34; P = .297), time on ventilation (SMD, 1.09; P = .318), drug-related adverse events (OR, drug-related adverse events (OR, 1.66; P = .319) and mortality (OR, 2.21; P = .261)]. Subgroup analysis also confirmed the benefit of suvorexant on the development of delirium, which was significant in any subgroup.

CONCLUSION

Suvorexant should be recommended for the prevention of delirium in clinic.

Prevalence and risk factors of delirium in the intensive care unit: An observational study

BACKGROUND

Several risk factors, such as age, alcohol abuse, dementia, and severe illness, can contribute to the development of delirium. However, limited information is available in the literature regarding the risk of delirium among surgical, trauma, neurological, and medical intensive care patients.

AIM

To describe the prevalence of risk factors associated with delirium in intensive care units.

DESIGN

This study used an observational design.

METHODS

We enrolled 165 patients hospitalized in two intensive care units in Italy. Patients were first evaluated using the Prediction of Delirium model and were subsequently evaluated using the Intensive Care Delirium Screening Checklist; evaluation lasted a maximum of 5 days for each admitted patient after sedation. A logistic regression model was used to identify the prevalence and risk factors of delirium.

RESULTS

The average age of the patients was 57.6 (SD = 18.3) years, and the patients were predominantly male (65.0%). The majority of patients had been subjected to trauma (38.8%); 37.6% had undergone general surgical interventions, and 23.6% had undergone medical interventions. Delirium occurred in 55.8% of the 165 patients. The risk of delirium was independently associated with coma (odds ratio = 10.6; 95% confidence interval, 3.08-39.9) and the Acute Physiology and Chronic Health Evaluation II score (odds ratio = 4.27; 95% confidence interval, 1.58-11.53).

CONCLUSIONS

This study confirmed that coma and the Acute Physiology and Chronic Health Evaluation II score were non-modifiable risk factors for delirium. Further studies could categorize the different types of coma. Proper delirium management could limit the impact on the recovery of these patients, their autonomy, and their reintegration into the social and professional world.

RELEVANCE TO CLINICAL PRACTICE

Delirium increases intensive care unit and hospital length of stay. Early identification and risk factor assessment by critical care nurses are considered the key factors in the treatment of delirium.

Risk factors and outcomes among delirium subtypes in adult ICUs: A systematic review

PURPOSE

Use systematic review methodology to summarize risk factors and outcomes for each delirium subtype (hypoactive, hyperactive and mixed) in an adult ICU population.

MATERIALS AND METHODS

We searched the MEDLINE, Embase, CINAHL, SCOPUS, Web of Science and PsycINFO databases from database inception until August 13, 2018, with no restrictions.

RESULTS

Of 9635 abstracts, 20 studies were included. Older age was not associated with any delirium subtype in 4/7 (57%) studies. Sex was not associated with any delirium subtype in 4/4 (100%) studies. Mortality was consistently associated with hypoactive delirium in 4/7 (57%) studies. The evidence supporting the association of APACHE-II score, mechanical ventilation, length of stay, duration of delirium and removal of tubes were inconsistent across studies.

CONCLUSIONS

Although included studies reported on many subtype-specific risk factors and outcomes, heterogeneity in reporting and methodological quality limited the generalizability of the results and the evidence for many subtype-specific risk factors or outcomes is inconsistent across studies. Standardized methodology and the creation of a universal template for collecting data in ICU delirium studies are essential moving forward; helping to identify subtype-specific risk factors or outcomes and strengthen the association of potential risk factors or outcomes.

Incidence, risk factors, and cumulative risk of delirium among ICU patients: A case-control study

Objectives

Delirium is a common acute cognitive impairment syndrome among intensive care unit (ICU) patients. This study was aimed to investigate the incidence, risk factors, and cumulative risk of delirium among ICU patients.

Methods

A case-control study including clinical records of 452 patients were retrospectively analyzed. Delirium was assessed using the Confusion Assessment Method for the ICU and Richmond Agitation–Sedation Scale.

Results

We found that 163 out of the 452 patients (36.1%) had delirium. Multivariate analysis showed that use of sedatives, length of ICU hospitalization, and physical restraint were independent risk factors for delirium. The additive effect of all three factors resulted to an odds ratio of 30.950.

Conclusion

The incidence of delirium remained high. Thus, nurses shall strengthen the monitoring of delirium, regularly access the patient's level of calmness, and limit the use of physical restraint.

In a Model of Neuroinflammation Designed to Mimic Delirium, Quetiapine Reduces Cortisol Secretion and Preserves Reversal Learning in the Attentional Set Shifting Task

Quetiapine, an atypical antipsychotic medication has lacked pre-clinical validation for its purported benefits in the treatment of delirium. This laboratory investigation examined the effects of quetiapine on the attentional set shifting task (ASST), a measure of cognitive flexibility and executive functioning, in a rodent model of lipopolysaccharide (LPS) mediated neuroinflammation. 19 Sprague Dawley female rats were randomly selected to receive intraperitoneal placebo (N = 5), LPS and placebo (N = 7) or LPS and quetiapine (n = 7) and performed the ASST. We measured trials to criterion, errors, non-locomotion episodes and latency to criterion, serum cortisol and tumor necrosis factor alpha (TNF-α) levels. TNF-α levels were not different between groups at 24 h. Cortisol levels in the LPS + Quetiapine group were reduced compared to LPS + Placebo (P < 0.001) and did not differ from the placebo group (P = 0.15). Analysis between LPS + Quetiapine and LPS + Placebo treated rats demonstrated improvement in the compound discrimination reversal (CD Rev1) (P = 0.016) and the intra-dimensional reversal (ID Rev2) (P = 0.007) discriminations on trials to criterion. LPS + Quetiapine treated rats had fewer errors than LPS + Placebo treated animals in the compound discrimination (CD) (P = 0.007), CD Rev1 (P = 0.005), ID Rev2 (P < 0.001) discriminations. There was no difference in non-locomotion frequency or latency to criterion between the three groups in all discriminations (P > 0.0167). We demonstrated preserved reversal learning, no effect on attentional set shifting and normalized cortisol levels in quetiapine-treated rats in this neuroinflammatory model of delirium. This suggests that quetiapine's beneficial effects in delirium may be related to the preservation of reversal learning and potential downstream effects related to reduction in cortisol production. Graphical Abstract.

Risk factors for delirium: are therapeutic interventions part of it?

Background: Delirium is associated with increased morbidity and mortality in critically ill patients. Research on risk factors for delirium allows clinicians to identify high-risk patients, which is the basis for early prevention and diagnosis. Besides the risk factors for delirium that are commonly studied, here we more focused on the less-studied therapeutic interventions for critically ill patients which are potentially modifiable. Materials and methods: A total of 320 non-comatose patients admitted to the ICU for more than 24 hrs during 9 months were eligible for the study. Delirium was screened once daily using the CAM-ICU. Demographics, admission clinical data, and daily interventions were collected. Results: Ninety-two patients (28.75%) experienced delirium at least once. Delirious patients were more likely to have longer duration of mechanical ventilation, ICU stay, and hospital stay. Most of the less-studied therapeutic interventions were linked to delirium in the univariate analysis, including gastric tube, artificial airway, deep intravenous catheter, arterial line, urinary catheter, use of vasoactive drugs, and sedative medication. After adjusting with age and ICU length of stay, mechanical ventilation (OR: 5.123; 95% CI: 2.501-10.494), Acute Physiology and Chronic Health Evaluation (APACHE) II score≥20 at admission (OR: 1.897; 95% CI: 1.045-3.441), and gastric tube (OR: 1.935, 95% CI: 1.012-3.698) were associated with increased risk of delirium in multivariate analysis. Conclusion: Delirium was associated with prolonged mechanical ventilation, ICU stay, and hospital stay. Multivariate risk factors were gastric tube, mechanical ventilation, and APACHE II score. Although being a preliminary study, this study suggests the necessity of earliest removal of tubes and catheters when no longer needed.

Addition of Suvorexant to Ramelteon Therapy for Improved Sleep Quality with Reduced Delirium Risk in Acute Stroke Patients

BACKGROUND AND PURPOSE

Delirium in acute stroke is associated with poor clinical outcome. The purpose of this study was to examine the effect of sleep medications on sleep quality and delirium in acute stroke.

METHODS

In this retrospective cohort study, sleep disturbances, and delirium were investigated in acute stroke patients treated in April 2013-March 2017 who were prescribed ramelteon plus either an alpha-aminobutyric acid receptor (GABAR) agonist or a selective dual orexin receptor antagonist (suvorexant).

RESULTS

Of the patients included, 104 received a GABAR agonist and 128 received suvorexant in addition to ramelteon. Patient characteristics did not differ significantly between the groups, except for a higher proportion of cerebral infarction in suvorexant group (P = .033). Subjective sleep quality was significantly improved in suvorexant group compared to GABAR agonist group (difficulty staying asleep: 6.3% versus 34%, P < .001; daytime sleepiness: 33% versus 63%, P < .001). Delirium was significantly less frequent in suvorexant group than GABAR agonist group (7.0% versus 31%, P < .001). The length of hospital stay was significantly shorter in suvorexant group than in GABAR agonist group (in days, 21 [15-29] versus 25 [18-33]; P = .019). Multivariable logistic regression analysis revealed that the addition of suvorexant was significantly associated with a reduced occurrence of delirium (odds ratios .19, 95% confidence interval .085-.43, P < .001).

CONCLUSIONS

Addition of suvorexant to ramelteon therapy, rather than a GABA receptor agonist, can improve subjective sleep quality without inducing delirium in acute stroke patients.

Prevalence and risk factors related to haloperidol use for delirium in adult intensive care patients: the multinational AID-ICU inception cohort study

PURPOSE

We assessed the prevalence and variables associated with haloperidol use for delirium in ICU patients and explored any associations of haloperidol use with 90-day mortality.

METHODS

All acutely admitted, adult ICU patients were screened during a 2-week inception period. We followed the patient throughout their ICU stay and assessed 90-day mortality. We assessed patients and their variables in the first 24 and 72 h in ICU and studied their association together with that of ICU characteristics with haloperidol use.

RESULTS

We included 1260 patients from 99 ICUs in 13 countries. Delirium occurred in 314/1260 patients [25% (95% confidence interval 23-27)] of whom 145 received haloperidol [46% (41-52)]. Other interventions for delirium were benzodiazepines in 36% (31-42), dexmedetomidine in 21% (17-26), quetiapine in 19% (14-23) and olanzapine in 9% (6-12) of the patients with delirium. In the first 24 h in the ICU, all subtypes of delirium [hyperactive, adjusted odds ratio (aOR) 29.7 (12.9-74.5); mixed 10.0 (5.0-20.2); hypoactive 3.0 (1.2-6.7)] and circulatory support 2.7 (1.7-4.3) were associated with haloperidol use. At 72 h after ICU admission, circulatory support remained associated with subsequent use of haloperidol, aOR 2.6 (1.1-6.9). Haloperidol use within 0-24 h and within 0-72 h of ICU admission was not associated with 90-day mortality [aOR 1.2 (0.5-2.5); p = 0.66] and [aOR 1.9 (1.0-3.9); p = 0.07], respectively.

CONCLUSIONS

In our study, haloperidol was the main pharmacological agent used for delirium in adult patients regardless of delirium subtype. Benzodiazepines, other anti-psychotics and dexmedetomidine were other frequently used agents. Haloperidol use was not statistically significantly associated with increased 90-day mortality.