Risk factors and outcomes of sepsis-associated delirium in intensive care unit patients: A secondary data analysis

Nursing diagnoses as factors associated with delirium among intensive care unit patients with sepsis: A retrospective correlational study

AIMS

To examine whether nursing diagnoses were associated with delirium in patients with sepsis.

BACKGROUND

Nursing diagnosis is a nurse's clinical judgement about clients' current or potential health conditions. Delirium is regarded as an important nurse-sensitive outcome. Nonetheless, nursing diagnoses associated with delirium have not yet been identified.

DESIGN

Retrospective correlational study.

METHODS

This study was carried out from December 2021 to January 2023. We analysed electronic health records of patients with sepsis admitted to the intensive care units (ICUs) of a tertiary hospital in Seoul, South Korea. Delirium was defined based on the Intensive Care Delirium Screening Checklist score. Nursing diagnoses established within 24 h of admission to the ICU were included and were based on the North American Nursing Diagnosis Association diagnostic classification. The data were analysed using logistic regression. Demographics, comorbidities, procedures and physiological measures were adjusted. Regression model was evaluated via receiver operating characteristic curve, Nagelkerke R2, accuracy and F1 score.

RESULTS

The prevalence of delirium in patients with sepsis was 51.8%. Ineffective breathing patterns, decreased cardiac output and impaired skin integrity were significant nursing diagnoses related to delirium. Age ≥ 65 years, Acute Physiology and Chronic Health Evaluation II score, mechanical ventilation, continuous renal replacement therapy, physical restraint and comatose state were also associated with delirium in patients with sepsis. The area under the receiver operating characteristic curve was 0.806.

CONCLUSION

Ineffective breathing patterns, decreased cardiac output and impaired skin integrity could manifest as prodromal symptoms of delirium among patients with sepsis.

IMPACT

The prodromal symptoms of delirium revealed through nursing diagnoses can be efficiently used to identify high-risk groups for delirium. The use of nursing diagnosis system should be recommended in clinical practice caring for sepsis patients.

REPORTING METHODS

STROBE checklist.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public involvement.

Post-sepsis psychiatric disorder: Pathophysiology, prevention, and treatment

Post-sepsis psychiatric disorder, encompassing anxiety, depression, post-traumatic stress disorder and delirium, is a highly prevalent complication secondary to sepsis, resulting in a marked increase in long-term mortality among affected patients. Regrettably, psychiatric impairment associated with sepsis is frequently disregarded by clinicians. This review aims to summarize recent advancements in the understanding of the pathophysiology, prevention, and treatment of post-sepsis mental disorder, including coronavirus disease 2019-related psychiatric impairment. The pathophysiology of post-sepsis psychiatric disorder is complex and is known to involve blood-brain barrier disruption, overactivation of the hypothalamic-pituitary-adrenal axis, neuroinflammation, oxidative stress, neurotransmitter dysfunction, programmed cell death, and impaired neuroplasticity. No unified diagnostic criteria for this disorder are currently available; however, screening scales are often applied in its assessment. Modifiable risk factors for psychiatric impairment post-sepsis include the number of experienced traumatic memories, the length of ICU stay, level of albumin, the use of vasopressors or inotropes, daily activity function after sepsis, and the cumulative dose of dobutamine. To contribute to the prevention of post-sepsis psychiatric disorder, it may be beneficial to implement targeted interventions for these modifiable risk factors. Specific therapies for this condition remain scarce. Nevertheless, non-pharmacological approaches, such as comprehensive nursing care, may provide a promising avenue for treating psychiatric disorder following sepsis. In addition, although several therapeutic drugs have shown preliminary efficacy in animal models, further confirmation of their potential is required through follow-up clinical studies.

The incidence of neurological complications in mechanically ventilated COVID-19 ICU patients: An observational single-center cohort study in three COVID-19 periods

BACKGROUND

Neurological complications in COVID-19 patients admitted to an intensive care unit (ICU) have been previously reported. As the pandemic progressed, therapeutic strategies were tailored to new insights. This study describes the incidence, outcome, and types of reported neurological complications in invasively mechanically ventilated (IMV) COVID-19 patients in relation to three periods during the pandemic.

METHODS

IMV COVID-19 ICU patients from the Dutch Maastricht Intensive Care COVID (MaastrICCht) cohort were included in a single-center study (March 2020 - October 2021). Demographic, clinical, and follow-up data were collected. Electronic medical records were screened for neurological complications during hospitalization. Three distinct periods (P1, P2, P3) were defined, corresponding to periods with high hospitalization rates. ICU survivors with and without reported neurological complications were compared in an exploratory analysis.

RESULTS

IMV COVID-19 ICU patients (n=324; median age 64 [IQR 57-72] years; 238 males (73.5%)) were stratified into P1 (n=94), P2 (n=138), and P3 (n=92). ICU mortality did not significantly change over time (P1=38.3%; P2=41.3%; P3=37.0%; p=.787). The incidence of reported neurological complications during ICU admission gradually decreased over the periods (P1=29.8%; P2=24.6%; P3=18.5%; p=.028). Encephalopathy/delirium (48/324 (14.8%)) and ICU-acquired weakness (32/324 (9.9%)) were most frequently reported and associated with ICU treatment intensity. ICU survivors with neurological complications (n=53) were older (p=.025), predominantly male (p=.037), and had a longer duration of IMV (p<.001) and ICU stay (p<.001), compared to survivors without neurological complications (n=132). A multivariable analysis revealed that only age was independently associated with the occurrence of neurological complications (ORadj=1.0541; 95% CI=1.0171-1.0925; p=.004). Health-related quality-of-life at follow-up was not significantly different between survivors with and without neurological complications (n = 82, p=.054).

CONCLUSIONS

A high but decreasing incidence of neurological complications was reported during three consecutive COVID-19 periods in IMV COVID-19 patients. Neurological complications were related to the intensity of ICU support and treatment, and associated with prolonged ICU stay, but did not lead to significantly worse reported health-related quality-of-life at follow-up.

Factors contributing to sepsis-associated encephalopathy: a comprehensive systematic review and meta-analysis

Background

This study aims to systematically assess the risk factors, the overall strength of association, and evidence quality related to sepsis-associated encephalopathy.

Methods

A systematic search was conducted in the Cochrane Library, PubMed, Web of Science, and Embase for cohort or case-control studies published up to August 2023 on risk factors associated with sepsis-related encephalopathy. The selected studies were screened, data were extracted, and the quality was evaluated using the Newcastle-Ottawa Scale. Meta-analysis was performed using RevMan 5.3 software. The certainty of the evidence was assessed using the GRADE criteria.

Results

A total of 13 studies involving 1,906 participants were included in the analysis. Among these studies, 12 were of high quality, and one was of moderate quality. Our meta-analysis identified six risk factors significantly associated with Serious Adverse Events (SAE). These included APACHE II, SOFA, age, tau protein, and IL-6, which were found to be risk factors with significant effects (standard mean difference SMD: 1.24-2.30), and albumin, which was a risk factor with moderate effects (SMD: -0.55). However, the certainty of evidence for the risk factors identified in this meta-analysis ranged from low to medium.

Conclusion

This systematic review and meta-analysis identified several risk factors with moderate to significant effects. APACHE II, SOFA, age, tau protein, IL-6, and albumin were associated with sepsis-related encephalopathy and were supported by medium- to high-quality evidence. These findings provide healthcare professionals with an evidence-based foundation for managing and treating hospitalized adult patients with sepsis-related encephalopathy.

Improved prediction of sepsis-associated encephalopathy in intensive care unit sepsis patients with an innovative nomogram tool

Background

Sepsis-associated encephalopathy (SAE) occurs as a result of systemic inflammation caused by sepsis. It has been observed that the majority of sepsis patients experience SAE while being treated in the intensive care unit (ICU), and a significant number of survivors continue suffering from cognitive impairment even after recovering from the illness. The objective of this study was to create a predictive nomogram that could be used to identify SAE risk factors in patients with ICU sepsis.

Methods

We conducted a retrospective cohort study using the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. We defined SAE as a Glasgow Coma Scale (GCS) score of 15 or less, or delirium. The patients were randomly divided into training and validation cohorts. We used least absolute shrinkage and selection operator (LASSO) regression modeling to optimize feature selection. Independent risk factors were determined through a multivariable logistic regression analysis, and a prediction model was built. The performance of the nomogram was evaluated using various metrics including the area under the receiver operating characteristic curve (AUC), calibration plots, Hosmer-Lemeshow test, decision curve analysis (DCA), net reclassification improvement (NRI), and integrated discrimination improvement (IDI).

Results

Among the 4,476 sepsis patients screened, 2,781 (62.1%) developed SAE. In-hospital mortality was higher in the SAE group compared to the non-SAE group (9.5% vs. 3.7%, p < 0.001). Several variables were analyzed, including the patient's age, gender, BMI on admission, mean arterial pressure, body temperature, platelet count, sodium level, and use of midazolam. These variables were used to create and validate a nomogram. The nomogram's performance, assessed by AUC, NRI, IDI, and DCA, was found to be superior to the conventional SOFA score combined with delirium. Calibration plots and the Hosmer-Lemeshow test confirmed the accuracy of the nomogram. The enhanced NRI and IDI values demonstrated that our scoring system outperformed traditional diagnostic approaches. Additionally, the DCA curve indicated the practicality of the nomogram in clinical settings.

Conclusion

This study successfully identified autonomous risk factors associated with the emergence of SAE in sepsis patients and utilized them to formulate a predictive model. The outcomes of this investigation have the potential to serve as a valuable clinical resource for the timely detection of SAE in patients.

Evaluating early lymphocyte-to-monocyte ratio as a predictive biomarker for delirium in older adult patients with sepsis: insights from a retrospective cohort analysis

Background

This study aims to explore the value of the Lymphocyte-to-Monocyte Ratio (LMR) in predicting delirium among older adult patients with sepsis.

Methods

Retrospective data were obtained from the MIMIC-IV database in accordance with the STROBE guidelines. Patients aged 65 and above, meeting the Sepsis 3.0 criteria, were selected for this study. Delirium was assessed using the Confusion Assessment Method for the ICU (CAM-ICU). Demographic information, comorbid conditions, severity of illness scores, vital sign measurements, and laboratory test results were meticulously extracted. The prognostic utility of the Lymphocyte-to-Monocyte Ratio (LMR) in predicting delirium was assessed through logistic regression models, which were carefully adjusted for potential confounding factors.

Results

In the studied cohort of 32,971 sepsis patients, 2,327 were identified as meeting the inclusion criteria. The incidence of delirium within this subgroup was observed to be 55%. A univariate analysis revealed a statistically significant inverse correlation between the Lymphocyte-to-Monocyte Ratio (LMR) and the risk of delirium (p < 0.001). Subsequent multivariate analysis, which accounted for comorbidities and illness severity scores, substantiated the role of LMR as a significant predictive marker. An optimized model, achieving the lowest Akaike Information Criterion (AIC), incorporated 17 variables and continued to demonstrate LMR as a significant prognostic factor (p < 0.01). Analysis of the Receiver Operating Characteristic (ROC) curve indicated a significant enhancement in the Area Under the Curve (AUC) upon the inclusion of LMR (p = 0.035).

Conclusion

The Lymphocyte-to-Monocyte Ratio (LMR) serves as a significant, independent prognostic indicator for the occurrence of delirium in older adult patients with sepsis. Integrating LMR into existing predictive models markedly improves the identification of patients at elevated risk, thereby informing and potentially guiding early intervention strategies.

Development of a machine learning-based prediction model for sepsis-associated delirium in the intensive care unit

Septic patients in the intensive care unit (ICU) often develop sepsis-associated delirium (SAD), which is strongly associated with poor prognosis. The aim of this study is to develop a machine learning-based model for the early prediction of SAD. Patient data were extracted from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database and the eICU Collaborative Research Database (eICU-CRD). The MIMIC-IV data were divided into a training set and an internal validation set, while the eICU-CRD data served as an external validation set. Feature variables were selected using least absolute shrinkage and selection operator regression, and prediction models were built using logistic regression, support vector machines, decision trees, random forests, extreme gradient boosting (XGBoost), k-nearest neighbors and naive Bayes methods. The performance of the models was evaluated in the validation set. The model was also applied to a group of patients who were not assessed or could not be assessed for delirium. The MIMIC-IV and eICU-CRD databases included 14,620 and 1723 patients, respectively, with a median time to diagnosis of SAD of 24 and 30 h. Compared with Non-SAD patients, SAD patients had higher 28-days ICU mortality rates and longer ICU stays. Among the models compared, the XGBoost model had the best performance and was selected as the final model (internal validation area under the receiver operating characteristic curves (AUROC) = 0.793, external validation AUROC = 0.701). The XGBoost model outperformed other models in predicting SAD. The establishment of this predictive model allows for earlier prediction of SAD compared to traditional delirium assessments and is applicable to patients who are difficult to assess with traditional methods.

Lipopolysaccharide-Induced Delirium-like Behaviour in a Rat Model of Chronic Cerebral Hypoperfusion Is Associated with Increased Indoleamine 2,3-Dioxygenase Expression and Endotoxin Tolerance

Indoleamine 2,3-dioxygenase (IDO) and the tryptophan-kynurenine pathway (TRP-KP) are upregulated in ageing and could be implicated in the pathogenesis of delirium. This study evaluated the role of IDO/KP in lipopolysaccharide (LPS)-induced delirium in an animal model of chronic cerebral hypoperfusion (CCH), a proposed model for delirium. CCH was induced by a permanent bilateral common carotid artery ligation (BCCAL) in Sprague Dawley rats to trigger chronic neuroinflammation-induced neurodegeneration. Eight weeks after permanent BCCAL, the rats were treated with a single systemic LPS. The rats were divided into three groups: (1) post-BCCAL rats treated with intraperitoneal (i.p.) saline, (2) post-BCCAL rats treated with i.p. LPS 100 μg/kg, and (3) sham-operated rats treated with i.p. LPS 100 μg/kg. Each group consisted of 10 male rats. To elucidate the LPS-induced delirium-like behaviour, natural and learned behaviour changes were assessed by a buried food test (BFT), open field test (OFT), and Y-maze test at 0, 24-, 48-, and 72 h after LPS treatment. Serum was collected after each session of behavioural assessment. The rats were euthanised after the last serum collection, and the hippocampi and cerebral cortex were collected. The TRP-KP neuroactive metabolites were measured in both serum and brain tissues using ELISA. Our data show that LPS treatment in CCH rats was associated with acute, transient, and fluctuated deficits in natural and learned behaviour, consistent with features of delirium. These behaviour deficits were mild compared to the sham-operated rats, which exhibited robust behaviour impairments. Additionally, heightened hippocampal IDO expression in the LPS-treated CCH rats was associated with reduced serum KP activity together with a decrease in the hippocampal quinolinic acid (QA) expression compared to the sham-operated rats, suggested for the presence of endotoxin tolerance through the immunomodulatory activity of IDO in the brain. These data provide new insight into the underlying mechanisms of delirium, and future studies should further explore the role of IDO modulation and its therapeutic potential in delirium.

Sepsis-Associated Delirium: A Narrative Review

Delirium is characterized by an acutely altered mental status accompanied by reductions in cognitive function and attention. Delirium in septic patients, termed sepsis-associated delirium (SAD), differs in several specific aspects from the other types of delirium that are typically encountered in intensive care units. Since sepsis and delirium are both closely associated with increased morbidity and mortality, it is important to not only prevent but also promptly diagnose and treat SAD. We herein reviewed the etiology, pathogenesis, risk factors, prevention, diagnosis, treatment, and prognosis of SAD, including coronavirus disease 2019 (COVID-19)-related delirium. Delirium by itself not only worsens long-term prognosis, but it is also regarded as an important factor affecting the outcome of post-intensive care syndrome. In COVID-19 patients, the difficulties associated with adequately implementing the ABCDEF bundle (Assess, prevent, and manage pain; Both spontaneous awakening and breathing trials: Choice of analgesia and sedation; Delirium assess, prevent, and manage; Early mobility and exercise; Family engagement/empowerment) and the need for social isolation are issues that require the development of conventional care for SAD.

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.

Immunological risk factors for sepsis-associated delirium and mortality in ICU patients

Background

A major challenge in intervention of critical patients, especially sepsis-associated delirium (SAD) intervention, is the lack of predictive risk factors. As sepsis and SAD are heavily entangled with inflammatory and immunological processes, to identify the risk factors of SAD and mortality in the intensive care unit (ICU) and determine the underlying molecular mechanisms, the peripheral immune profiles of patients in the ICU were characterized.

Methods

This study contains a cohort of 52 critical patients who were admitted to the ICU of the First Affiliated Hospital of Jinan University. Comorbidity, including sepsis and SAD, of this cohort was diagnosed and recorded. Furthermore, peripheral blood samples were collected on days 1, 3, and 5 of admission for peripheral immune profiling with blood routine examination, flow cytometry, ELISA, RNA-seq, and qPCR.

Results

The patients with SAD had higher mortality during ICU admission and within 28 days of discharge. Compared with survivors, nonsurvivors had higher neutrophilic granulocyte percentage, higher CRP concentration, lower monocyte count, lower monocyte percentage, lower C3 complement level, higher CD14^loCD16⁺ monocytes percentage, and higher levels of IL-6 and TNFα. The CD14^hiCD16^- monocyte percentage manifested favorable prediction values for the occurrence of SAD. Differentially expressed genes between the nonsurvival and survival groups were mainly associated with immune response and metabolism process. The longitudinal expression pattern of SLC2A1 and STIMATE were different between nonsurvivors and survivors, which were validated by qPCR.

Conclusions

Nonsurvival critical patients have a distinct immune profile when compared with survival patients. CD14^hiCD16^- monocyte prevalence and expression levels of SLC2A1 and STIMATE may be predictors of SAD and 28-day mortality in ICU patients.

A delirium prevalence audit and a pre and post evaluation of an interprofessional education intervention to increase staff knowledge about delirium in older adults

Background

Delirium is more prevalent in older people and estimated to occur in up to 50% of the hospital population. Delirium comprises a spectrum of behaviours, including cognitive and attention deficits, and fluctuating levels of consciousness, often associated with an underlying physiological disturbance. Delirium has been increasingly associated with adverse outcomes. Although often preventable or can at least be mitigated, delirium may not be a standard part of assessment and thus may not be recognized in the early stages when it is most likely to be treated successfully. The aim of this study was to evaluate the level of knowledge of delirium amongst clinicians caring for patients at high risk of developing delirium and to determine whether education can improve clinical assessment of delirium.

Methods

Two hundred and forty-six case notes were audited before and 149 were reviewed after the education intervention and implementation of a delirium screening tool. Clinicians at the hospital were invited to complete a questionnaire on knowledge of delirium. The questionnaire was based on a validated tool which contained 39 questions about delirium. The questionnaire also contained 28 questions on delirium knowledge. Additional questions were included to gather demographic information specific to the hospital. Descriptive statistics, chi square and independent t-tests were conducted to test for differences in knowledge between the pre and post periods. The Squire Checklist Reporting Guidelines for Quality Improvement Studies informed the preparation of the manuscript.

Results

The audit demonstrated that the use of a cognitive assessment tool overall increased from 8.5% in pre education to 43% in the post education period. One hundred and fifty-nine staff completed the questionnaire in total, 118 the pre and 41 post. The knowledge subscale score was high pre and post education and no statistically significant difference was observed. The greatest increase in knowledge was related to knowledge of the risk factors subscale. The increase in knowledge (6.8%) was statistically significant.

Conclusion

An interprofessional approach to delirium education was effective in not only increasing awareness of the factors associated with this syndrome but also increased the use of a delirium assessment tool.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12912-021-00692-2.

Delirium and Associated Length of Stay and Costs in Critically Ill Patients

Purpose

Delirium frequently affects critically ill patients in the intensive care unit (ICU). The purpose of this study is to evaluate the impact of delirium on ICU and hospital length of stay (LOS) and perform a cost analysis.

Materials and Methods

Prospective studies and randomized controlled trials of patients in the ICU with delirium published between January 1, 2015, and December 31, 2020, were evaluated. Outcome variables including ICU and hospital LOS were obtained, and ICU and hospital costs were derived from the respective LOS.

Results

Forty-one studies met inclusion criteria. The mean difference of ICU LOS between patients with and without delirium was significant at 4.77 days (p < 0.001); for hospital LOS, this was significant at 6.67 days (p < 0.001). Cost data were extractable for 27 studies in which both ICU and hospital LOS were available. The mean difference of ICU costs between patients with and without delirium was significant at $3,921 (p < 0.001); for hospital costs, the mean difference was $5,936 (p < 0.001).

Conclusion

ICU and hospital LOS and associated costs were significantly higher for patients with delirium, compared to those without delirium. Further research is necessary to elucidate other determinants of increased costs and cost-reducing strategies for critically ill patients with delirium. This can provide insight into the required resources for the prevention of delirium, which may contribute to decreasing healthcare expenditure while optimizing the quality of care.

Screening for delirium in the intensive care unit using eDIS-ICU - A purpose-designed app: A pilot study

INTRODUCTION

Delirium, a common complication of an intensive care unit (ICU) admission, is inconsistently diagnosed by clinicians. Current screening tools require specialist expertise and/or training. Some are time-consuming to administer, and reliability in routine clinical practice is questionable. An innovative app designed to enable efficient and sensitive screening for delirium without specialist training (eDIS-ICU) has recently been described. This pilot study compared the eDIS-ICU against the reference standard expert assessment using DSM-V (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition) criteria and the Confusion Assessment Method for the ICU (CAM-ICU).

METHODS

In this prospective, single-centre pilot study, a convenience sample of 29 ICU patients were recruited at a tertiary referral hospital between November 2018 and August 2019. After obtaining written consent, demographic and clinical data were collected, and the patients were screened for delirium using eDIS-ICU and CAM-ICU by two clinician researchers in random order. The patients were also assessed for presence of delirium independently by an expert clinician using a structured interview to diagnose as per DSM-V criteria. The results of screening and diagnosis were tabulated to allow comparison of screening tools against diagnosis; sensitivity and specificity of the tools were calculated.

RESULTS

Seven participants were diagnosed with delirium as per DSM-V criteria. The eDIS-ICU tool correctly identified six of these participants compared with two identified by CAM-ICU. The sensitivity of the eDIS-ICU tool was 86% (95% confidence interval [CI] = 81.5-100.0) compared with 29% (95% CI = 5.1-69.7) for CAM-ICU (p < 0.05), and the specificity was 73% (95% CI = 81.5-100.0) versus 96% (95% CI = 75.1-99.8), respectively.

CONCLUSION

The simple and novel eDIS-ICU delirium screening tool was noninferior to the CAM-ICU in detecting delirium as per DSM-V criteria. A definitive validation study is warranted.

Utility of a prediction model for delirium in intensive care unit patients (PRE-DELIRIC) in mechanically ventilated patients with sepsis

Aim

Delirium frequently develops in patients with sepsis during their intensive care unit (ICU) stay, which is associated with increased morbidity and mortality. A prediction model for delirium in patients in ICU, PRE‐DELIRIC, has been utilized in overall ICU patients, but its utility is uncertain among patients with sepsis. This study aims to examine the utility of PRE‐DELIRIC to predict delirium in mechanically ventilated patients with sepsis.

Methods

This is a post hoc analysis of a randomized clinical trial in eight Japanese ICUs, which aimed to evaluate the sedative strategy with/without dexmedetomidine in adult mechanically ventilated patients with sepsis. The Confusion Assessment Method for the ICU was used every day to assess for delirium throughout their ICU stay. We excluded patients who were delirious on the first day of ICU, those who were under sustained coma throughout their ICU stay, and those who stayed in the ICU less than 24 h. The discriminative ability of PRE‐DELIRIC was evaluated by measuring the area under the receiver operating characteristic curve (AUROC).

Results

Of the 201 patients enrolled in the trial, we analyzed 158 patients. The mean age was 69.4 ± 14.0 years, and 99 patients (63%) were men. Delirium occurred at least once during the ICU stay of 63 patients (40%). The AUROC of PRE‐DELIRIC was 0.60 (95% confidence interval, 0.50–0.69). Subgroup analyses indicated that PRE‐DELIRIC was useful in those with Sequential Organ Failure Assessment score >8 with AUROC of 0.65 (95% confidence interval, 0.51–0.77).

Conclusions

The PRE‐DELIRIC model could not predict delirium in mechanically ventilated patients with sepsis.