Detection of delirium in the intensive care unit: comparison of confusion assessment method for the intensive care unit with confusion assessment method ratings

Using Electroencephalogram Biosignal Changes for Delirium Detection in Intensive Care Units

ABSTRACT

BACKGROUND: Biosignal data acquired during quantitative electroencephalography (QEEG) research may ultimately be used to develop algorithms for more accurate detection of delirium. This study investigates the biosignal changes during delirium states by using the QEEG data of patients in a medical intensive care unit. METHODS: This observational study was conducted between September 2018 and December 2019 at a tertiary hospital in South Korea. Delirium was measured using the Korean version of Confusion Assessment Method for the Intensive Care Unit in intensive care unit patients. Quantitative EEG measurements were recorded for 20 minutes in a natural state without external treatment or stimuli, and QEEG data measured in the centroparietal and parietal regions with eyes open were selected for analysis. Power spectrum analysis with a 5-minute epoch was conducted on the selected 65 cases. RESULTS: QEEG changes in the presence of delirium indicated that alpha, beta, gamma, and spectral edge frequency 50% waves showed significantly lower absolute power spectra than the corresponding findings in the absence of delirium. Brain-mapping results showed that these brain waves were inactivated in delirious states. CONCLUSION: QEEG assessments can potentially detect the changes in the centroparietal and parietal regions of delirium patients. QEEG changes, including lower power spectra of alpha, beta, and gamma waves, and spectral edge frequency 50%, can be successfully used to distinguish delirium from the absence of delirium.

Prediction of Postoperative Delirium in Geriatric Hip Fracture Patients: A Clinical Prediction Model Using Machine Learning Algorithms

Introduction

Postoperative delirium in geriatric hip fracture patients adversely affects clinical and functional outcomes and increases costs. A preoperative prediction tool to identify high-risk patients may facilitate optimal use of preventive interventions. The purpose of this study was to develop a clinical prediction model using machine learning algorithms for preoperative prediction of postoperative delirium in geriatric hip fracture patients.

Materials & Methods

Geriatric patients undergoing operative hip fracture fixation were queried in the American College of Surgeons National Surgical Quality Improvement Program database (ACS NSQIP) from 2016 through 2019. A total of 28 207 patients were included, of which 8030 (28.5%) developed a postoperative delirium. First, the dataset was randomly split 80:20 into a training and testing subset. Then, a random forest (RF) algorithm was used to identify the variables predictive for a postoperative delirium. The machine learning-model was developed on the training set and the performance was assessed in the testing set. Performance was assessed by discrimination (c-statistic), calibration (slope and intercept), overall performance (Brier-score), and decision curve analysis.

Results

The included variables identified using RF algorithms were (1) age, (2) ASA class, (3) functional status, (4) preoperative dementia, (5) preoperative delirium, and (6) preoperative need for mobility-aid. The clinical prediction model reached good discrimination (c-statistic = .79), almost perfect calibration (intercept = −.01, slope = 1.02), and excellent overall model performance (Brier score = .15). The clinical prediction model was deployed as an open-access web-application: https://sorg-apps.shinyapps.io/hipfxdelirium/.

Discussion & Conclusions

We developed a clinical prediction model that shows promise in estimating the risk of postoperative delirium in geriatric hip fracture patients. The clinical prediction model can play a beneficial role in decision-making for preventative measures for patients at risk of developing a delirium. If found to be externally valid, clinicians might use the available web-based application to help incorporate the model into clinical practice to aid decision-making and optimize preoperative prevention efforts.

Electroencephalography of mechanically ventilated patients at high risk of delirium

Objective

Neurophysiological exploration of ICU delirium is limited. Here, we examined EEG characteristics of medical‐surgical critically ill patients with new‐onset altered consciousness state at high risk for ICU delirium.

Materials and methods

Pre‐planned analysis of non‐neurological mechanically ventilated medical‐surgical ICU subjects, who underwent a prospective multicenter randomized, controlled EEG study (NCT03129438, April 2017–November 2018). EEG characteristics, according to the 2012 ACNS nomenclature, included background activity, rhythmic periodic patterns/epileptic activity, amplitude, frequency, stimulus‐induced discharges, triphasic waves, reactivity, and NREM sleep. We explored EEG findings in delirious versus non‐delirious patients, specifically focusing on the presence of burst‐suppression and rhythmic periodic patterns (ictal‐interictal continuum), and ictal activity.

Results

We analyzed 91 patients (median age, 66 years) who underwent EEG because of new‐onset altered consciousness state at a median 5 days from admission; 42 patients developed delirium (46%). Burst‐suppression (10 vs 0%, p = .02), rhythmic/periodic patterns (43% vs 22%, p = .03) and epileptiform activity (7 vs 0%, p = .05) were more frequent in delirious versus non‐delirious patients. The presence of at least one of these abnormal EEG findings (32/91 patients; 35%) was associated with a significant increase in the likelihood of delirium (42 vs 15%, p = .006). Cumulative dose of sedatives and analgesics, as well as all other EEG characteristics, did not differ significantly between the two groups.

Conclusion

In mechanically ventilated non‐neurological critically ill patients with new‐onset alteration of consciousness, EEG showing burst‐suppression, rhythmic or periodic patterns, or seizures/status epilepticus indicate an increased risk of ICU delirium.

Delirium Among Adults Undergoing Solid Organ Transplantation

Purpose of Review

To summarize the research on post-operative delirium among patients undergoing solid organ transplantation in efforts to improve recognition, evaluation, and management, as well as highlight areas for future research.

Recent Findings

Delirium is a common complication in patients with organ failure before and after undergoing solid organ transplant (range: 4.7-47%). However, it is frequently unrecognized and underdiagnosed-even among those closely monitored after major surgery-given that its manifestation is often variable and inconsistent. Delirium has multifactorial etiologies comprising of a complex mix of predisposing recipient, donor, and transplant factors, as well as intraoperative and perioperative factors. Evidence suggests that delirium risk increases with presence of a greater number of such risk factors, and can lead to adverse outcomes such as increased hospital length of stay, time in the ICU, time on mechanical ventilators, graft dysfunction, graft loss, and mortality. Though no trials have been conducted among transplant populations specifically, delirium has been shown to be preventable among hospitalized older adults generally. Multicomponent, primary prevention strategies designed to target multiple risk factors of delirium, such as cognitive impairment, sleep deprivation, immobility, visual impairment, hearing impairment, and dehydration, have been identified as most effective. Whether these approaches translate to improvements in quality of life and long-term health outcomes among patients with organ failure before and after transplantation is yet to be determined.

Summary

Delirium is an important, common, yet potentially preventable complication among patients with organ failure. Future studies are needed to test the efficacy of multicomponent, primary prevention strategies on long-term health outcomes among these vulnerable populations.

The risk factors of postoperative delirium in patients with hip fracture: implication for clinical management

Background

Delirium is a common complication of hip surgery patients. It is necessary to investigate the epidemiological characteristics and related risk factors of delirium after hip fracture surgery, to provide evidence supports for the prevention and management of delirium.

Methods

Hip fracture patients admitted to our hospital for surgical treatment from March 2018 to March 2020 were identified as participants. The characteristics and laboratory examinations in patients with and without postoperative delirium were compared and analyzed. Logistic regression analyses were conducted to ascertain the independent risk factors, and the area under the curve (AUC) were calculated to analyze the predictive value.

Results

A total of 568 postoperative patients with hip fracture were included, the incidence of delirium in postoperative patients with hip fracture was 14.44 %. The preoperative albumin (OR 4.382, 2.501 ~ 5.538), history of delirium (OR 2.197, 1.094 ~ 3.253), TSH (OR1.245, 1.077 ~ 1.638), the resting score on the first postoperative day (OR1.235, 0.944 ~ 1.506) and age(OR1.185, 0.065 ~ 1.814) were the independent risk factors for the postoperative delirium in patients with hip fracture(all p < 0.05). The AUC of albumin, history of delirium, TSH, the resting score on the first postoperative day and age were 0.794, 0.754, 0.746, 0.721 and 0.689 respectively.

Conclusions

The incidence of delirium in postoperative patients with hip fracture is rather high, especially for patients with old age and history of delirium. Monitoring albumin, TSH and resting score may be beneficial to the management of postoperative delirium.

Geriatric assessment for older adults admitted to the emergency department: A systematic review and meta-analysis

BACKGROUND

Older adults are the most frequent users of emergency services. Comprehensive geriatric assessment (CGA) can help identify high-risk older adults at an early stage. We conducted a systematic review and meta-analysis to identify and evaluate CGA tools used in the emergency department (ED), analyze their predictive validity for adverse outcomes and recommend tools for this particular situation.

METHODS

We systematically searched Medline, Web of Science and CENTRAL for eligible articles published in peer-reviewed journals that observed patients ≥65 years admitted to the ED, used at least one assessment tool and reported adverse outcomes of interest. We performed a descriptive analysis and a bivariate meta-analysis of the diagnostic accuracy and predictive validity of the assessment tools for the chosen adverse outcomes.

RESULTS

28 eligible studies were included. The pooled sensitivity (95% CI) of the assessment tools for predicting mortality within short (28-90 days) and long (180-365 days) periods after the first ED visit was 0.77 (0.61-0.89) and 0.79 (0.46-0.96), respectively, with specificity (95% CI) values of 0.45 (0.32-0.59) and 0.37 (0.14-0.65). These findings indicate that the tools used in the included studies had modest predictive accuracy for mortality and were more appropriate for identifying individuals at high risk of readmission in the short term than in the long term.

CONCLUSIONS

Early use of assessment tools in the ED might improve clinical decision making and reduce negative outcomes for older adults.

Delirium Triage Screen/Brief Confusion Assessment Method in Adult Orthopaedic and Hematological Patients: A Validation Study

Delirium in the hospitalized orthopaedic patient is associated with numerous negative outcomes. Assessing for the presence of delirium using an accurate and reliable tool is essential. However, the number of validated screening tools is limited. The purpose of this study was to validate and test the reliability of the Delirium Triage Screening and brief Confusion Assessment Method (DTS/bCAM) to screen for delirium in non-intensive care (ICU) orthopaedic and hematological patients. This was a prospective, observational study. Seventy-six delirium assessments were completed on 19 orthopaedic patients and 10 hematological patients. The clinical nurse performed the DTS/bCAM during every 12-hour shift. Within 2 hours of this assessment, a research investigator performed both the DTS/bCAM and the Confusion Assessment Method (CAM). Each patient had a maximum of three assessments by a research investigator. Interrater reliability for the clinical nurse and the researcher was measured through comparison of positive and negative DTS/bCAM results. Validity was measured by comparing the matched DTS/bCAM and CAM results, both performed by the researcher. The DTS/bCAM and CAM results had 100% agreement. Two patients (7%) screened positive for delirium. Sensitivity of the DTS/bCAM was 100% (95% CI [15.8-100]) and specificity was 100% (95% CI [95.1, 100]). There was 86% agreement (43/50) between the clinical nurse and the researcher for the DTS/bCAM. In adult orthopaedic and hematological patients not receiving intensive care, the DTS/bCAM may be a valid, reliable, and rapid screening tool for delirium.

Effect of Tropisetron on Prevention of Emergence Delirium in Patients After Noncardiac Surgery: A Trial Protocol

IMPORTANCE

Postoperative delirium is a frequent disorder for patients undergoing surgery and is associated with poor outcomes. Delirium may occur in the immediate period after anesthesia administration and surgery. Tropisetron, which is frequently administrated for postoperative nausea and vomiting, is also a partial agonist of α7 nicotinic acetylcholine receptors associated with neuroprotective effects. Tropisetron may be the potential pharmacological treatment to decrease delirium after noncardiac surgery.

OBJECTIVE

To perform a randomized clinical trial to determine the efficacy and safety of tropisetron for prevention of emergence delirium in patients undergoing noncardiac surgery.

DESIGN, SETTING, AND PARTICIPANTS

This single-center, 2-arm randomized, double-blind, placebo-controlled trial will include 1508 patients undergoing noncardiac surgery. The intervention group will receive 5 mg of intravenous tropisetron before anesthesia induction, and patients in the control group will receive a placebo. The primary end point is the incidence of emergence delirium within 1 hour after tracheal tube removal, measured by the Confusion Assessment Method for the Intensive Care Unit score. The main secondary outcome is the incidence of postoperative delirium measured at 3 days of follow-up. An intention-to-treat principle will be used for all analyses.

DISCUSSION

Delirium remains the most common neuropsychiatric complication for patients after surgery. This will be the first randomized clinical study to evaluate whether tropisetron is effective in preventing emergence delirium. Results from this study will provide evidence for alteration of daily practice.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT04027751.

QTc prolongation after haloperidol administration in critically ill patients post cardiovascular surgery: A cohort study and review of the literature

Objective

From case reports, haloperidol administration has been associated with QTc prolongation, torsades de pointes, and sudden cardiac death. In a vulnerable population of critically ill patients after cardiac surgery, however, it is unclear whether haloperidol administration affects the QTc interval. Thus, the aim of this study is to explore the effect of haloperidol in low doses on this interval.

Method

This retrospective cohort study was performed on a cardio-surgical intensive care unit (ICU), screened 2,216 patients and eventually included 68 patients with delirium managed with oral and intravenous haloperidol. In this retrospective analysis, electrocardiograms were taken prior and within 24 h after haloperidol administration. The effect of haloperidol on QTc was determined with a Person correlation, and inter-group differences were measured with new long QT comparisons.

Results

In total, 68 patients were included, the median age was 71 (64–79) years and predominantly male (77%). Haloperidol administration followed ICU admission by three days and the cumulative dose was 4 (2–9) mg. As a result, haloperidol administration did not affect the QTc (r = 0.144, p = 0.23). In total, 31% (21/68 patients) had a long QT before and 27.9% (19/68 patients) after haloperidol administration. Only 12% (8/68 patients) developed a newly onset long QT. These patients were not different in the route of administration, cumulative haloperidol doses, comorbidities, laboratory findings, or medications.

Significance of results

These results indicated that low-dose intravenous haloperidol was safe and not clinically relevant for the development of a newly onset long QT syndrome or adverse outcomes and support recent findings inside and outside the ICU setting.

Regional cerebral oxygen saturation and postoperative delirium in endovascular surgery: a prospective cohort study

BACKGROUND

Delirium is an acute mental disorder and common postoperative complication. Monitoring regional cerebral oxygen saturation (rSO₂) in endovascular therapeutic surgery may allow real-time monitoring of cerebral desaturation, avoiding profound cerebral dysfunction, and reducing the incidence of delirium. We sought to examine the incidence of delirium in patients undergoing endovascular surgery.

METHODS

This was a clinical cohort trial (registered with http://www.clinicaltrials.gov [NCT02356133]). We monitored the rSO₂ of 43 patients undergoing general anesthesia and cerebral endovascular surgery. The occurrence of delirium after surgery was recorded with the Confusion Assessment Method (CAM). Multivariate logistic regression was performed to identify the main predictor of delirium.

RESULTS

rSO₂ was significantly different between the delirium and no-delirium groups. The occurrence of delirium was 35% in our cohort, and higher rSO₂ desaturation scores were significantly associated with profound delirium (higher CAM score; odds ratio = 1.002; P = 0.021). The maximum declines of systolic blood pressure were 24.86 (21.78-27.93) and 32.98 (28.78-37.19) in the no-delirium and delirium groups, respectively, which were significantly different (P = 0.002) but not closely associated with delirium in multivariate analysis (P = 0.512). Anesthesia, mechanical ventilation duration, and having two vascular risk factors differed significantly between groups but were poorly associated with delirium outcome.

CONCLUSIONS

Elevated rSO₂ desaturation score was predictive of the occurrence of postoperative delirium following endovascular surgery. Monitoring rSO₂ is invaluable for managing controlled hypotension during endovascular surgery and reducing postoperative delirium.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02356133 . Registered 1 February 2015. All statistical analysis results submitted August 4, 2018.

Methods of identifying delirium: A research protocol

Delirium is an acute disorder affecting up to 80% of intensive care unit (ICU) patients. It is associated with a 10-fold increase in cognitive impairment, triples the rate of in-hospital mortality, and costs $164 billion annually. Delirium acutely affects attention and global cognitive function with fluctuating symptoms caused by underlying organic etiologies. Early detection is crucial because the longer a patient experiences delirium the worse it becomes and the harder it is to treat. Currently, identification is through intermittent clinical assessment using standardized tools, like the Confusion Assessment Method for ICU. Such tools work well in clinical research but do not translate well into clinical practice because they are subjective, intermittent and have low sensitivity. As such, healthcare providers using these tools fail to recognize delirium symptoms as much as 80% of the time. Delirium-related biochemical derangement leads to electrical changes in electroencephalographic (EEG) patterns followed by behavioral signs and symptoms. However, continuous EEG monitoring is not feasible due to cost and need for skilled interpretation. Studies using limited-lead EEG show large differences between patients with and without delirium while discriminating delirium from other causes. The Ceribell is a limited-lead device that analyzes EEG. If it is capable of detecting delirium, it would provide an objective physiological monitor to identify delirium before symptom onset. This pilot study was designed to explore relationships between Ceribell and delirium status. Completion of this study will provide a foundation for further research regarding delirium status using the Ceribell data.

Delirium in the critically ill patient

Delirium is an acute and transient brain dysfunction that is characterized by disturbances in consciousness, affecting both its content (i.e., attention) and level (i.e., arousal). It affects as many as 50% of those admitted to an intensive care unit (ICU). Once believed to be an inconsequential outcome of critical illness, it is now recognized that delirium is harmful in both the short- and long-term. Despite occurring frequently in critically ill patients, delirium often goes unrecognized. Well-validated delirium screening tools, designed for use in the ICU, should be used to reliably detect delirium. The first step in delirium treatment is to identify and address potentially modifiable risk factors. Multiple trials have shown that benzodiazepines are a risk factor for delirium in a dose-dependent manner. Sedation with nonbenzodiazepine-based strategies are an effective means by which to reduce delirium. Nonpharmacologic strategies such as those which seek to reduce sensory impairment, sleep deprivation, and immobility are effective. Pharmacologic treatment with antipsychotics, though commonly used, is not supported by findings from placebo-controlled trials. Recent data support from multiple trials support the use of the "ABCDEF bundle" as a means by which to reduce delirium.

Delirium Tremens: Assessment and Management

Delirium Tremens (DT) falls in the most severe spectrum of alcohol withdrawal, which could potentially result in death, unless managed promptly and adequately. The prevalence of DT in general population is <1% and nearly 2% in patients with alcohol dependence. DT presents with a combination of severe alcohol withdrawal symptoms and symptoms of delirium with agitation and sometimes hallucination. Clinical and laboratory parameters which predict DT have been discussed. Assessment of DT includes assessment of severity of alcohol withdrawal, evaluation of delirium, and screening for underlying medical co-morbidities. Liver disease as a co-morbidity is very common in patients with DT and that could complicate the clinical presentation, determine the treatment choice, and influence the outcome. Benzodiazepines are the mainstay of treatment for DT. Diazepam and lorazepam are preferred benzodiazepine, depending upon the treatment regime and clinical context. In benzodiazepine refractory cases, Phenobarbital, propofol, and dexmedetomidine could be used.

Association of electroencephalogram trajectories during emergence from anaesthesia with delirium in the postanaesthesia care unit: an early sign of postoperative complications

BACKGROUND

Postoperative delirium is associated with an increased risk of morbidity and mortality, especially in the elderly. Delirium in the postanaesthesia care unit (PACU) could predict adverse clinical outcomes.

METHODS

We investigated a potential link between intraoperative EEG patterns and PACU delirium as well as an association of PACU delirium with perioperative outcomes, readmission and length of hospital stay. The risk factors for PACU delirium were also explored. Data were collected from 626 patients receiving general anaesthesia for procedures that would not interfere with frontal EEG recording.

RESULTS

Of the 626 subjects enrolled, 125 tested positive for PACU delirium. Whilst age, renal failure, and pre-existing neurological disease were associated with PACU delirium in the univariable analysis, the multivariable analysis revealed the importance of information derived from the EEG, anaesthetic technique, anaesthesia duration, and history of stroke or neurodegenerative disease. The occurrence of EEG burst suppression during maintenance [odds ratio (OR)=1.86 (1.13-3.05)] and the type of EEG emergence trajectory may be predictive of PACU delirium. Specifically, EEG emergence trajectories lacking significant spindle power were strongly associated with PACU delirium, especially in cases that involved ketamine or nitrous oxide [OR=6.51 (3.00-14.12)]. Additionally, subjects with PACU delirium were at an increased risk for readmission [OR=2.17 (1.13-4.17)] and twice as likely to stay >6 days in the hospital.

CONCLUSIONS

Specific EEG patterns were associated with PACU delirium. These findings provide valuable information regarding how the brain reacts to surgery and anaesthesia that may lead to strategies to predict PACU delirium and identify key areas of investigation for its prevention.

Development and feasibility of a smartphone-based test for the objective detection and monitoring of attention impairments in delirium in the ICU

PURPOSE

Delirium in the ICU is under-diagnosed. We evaluated feasibility and performance of a novel smartphone-based test for objectively detecting inattention in delirium.

MATERIAL AND METHODS

DelApp-ICU combines a behavioural assessment and an attention task, whereby participants follow simple commands and count serially presented circles (score range 0-12, lower scores indicating worse performance). We assessed feasibility through staff interviews. Then we performed a preliminary case-control study in patients with and without delirium (ascertained with the Confusion Assessment Method for the ICU) who underwent the DelApp-ICU on up to 4 days.

RESULTS

Forty-six patients (median age = 57.5 years, range 18-83) were assessed 89 times in total (N's = 46, 29, 10 and 4 for subsequent assessments; 33.7% delirious). DelApp-ICU scores were lower in delirium (N = 20; median = 0.5, Inter-Quartile Range (IQR) = 0-4.75) compared to no delirium (N = 26, median = 12, IQR = 8-12) on days 1, 2 and 3 (p < 0.001, p < 0.001 and p < 0.05, respectively). A DelApp-ICU score ≤6 was 100% sensitive and 96% specific to delirium on day 1. Positive and Negative Predictive Values were 91% and 100%, respectively. DelApp-ICU scores were responsive to changes in CAM-ICU status.

CONCLUSIONS

DelApp-ICU shows promise for assessing inattention and delirium in ICU patients, including longitudinally monitoring deficits and providing a metric of delirium severity.

Factors associated with delirium in critical patients in a health institution in Bucaramanga, Colombia

OBJECTIVE

To determine the incidence and the factors associated with delirium in intensive care unit patients.

METHODS

A cohort study conducted on 134 patients in the intensive care unit at a clinic in Bucaramanga, Colombia., who were recruited in the first 24hours following admission and on whom the Richmond Agitation-Sedation Scale (RASS), PRE-DELIRIC version in Spanish, and Confusion Assessment method for Intensive Care Unit (CAM-ICU) were applied; the outcome was evaluated through daily monitoring with CAM-ICU.

RESULTS

The incidence of delirium was 20.2%, the predominating type was hypoactive at 66.7%, followed by the hyperactive type at 7.4% and mixed at 25.9%. Fifty-two percent of the patients with delirium died. In the bivariate analysis, the use of sedatives (Relative Risk(RR) 2.4, 95% confidence interval (95% CI) = 1.2-4.5), infection (RR = 2. 8, 95% CI=1.3-5.9), metabolic acidosis (RR = 4 3, 95% CI=2.3-8.0), mechanical ventilation (RR = 4 6, 95% CI=2.0-10.6), aged over 60 years (RR = 2 3, 95% CI=1.09-5.3) and APACHE score greater than 14 (RR = 3. 0) (95% CI=1.1-8.2) were identified as risk factors for delirium. The multivariate analysis only found a relationship with infection (RR = 3 8, 95% CI=1.6-9.1) and being aged over 60 years (RR = 3 2, 95% CI 1.2-8.3).

CONCLUSIONS

delirium is frequent in patients in the intensive care unit, especially the hypoactive type. Half of the patients with delirium died. The main risk factors for delirium are infection and being over 60 years age, therefore, delirium prevention activities should focus on these critical patients.

Evaluation of PRE-DELIRIC (PREdiction of DELIRium in ICu patients) delirium prediction model for the patients in the intensive care unit

Introduction

Delirium not only compromises patient care, but is also associated with poorer outcomes: increased duration of mechanical ventilation, higher mortality, and greater long-term cognitive dysfunction. The PRE-DELIRIC model is a tool used to calculate the risk of the development of delirium. The classification of the patients into groups by risk allows efficient initiation of preventive measures. The goal of this study was to validate the PRE-DELIRIC model using the CAM-ICU (The Confusion Assessment Method for the Intensive Care Unit) method for the diagnosis of delirium.

Materials and methods

Patients admitted to the University Hospital of Vilnius during February 2015 were enrolled. Every day, data were collected for APACHE-II and PRE-DELIRIC scores. Out of 167 patients, 38 (23%) were included and screened using the CAM-ICU method within 24 hours of admission to the ICU. We defined patients as having delirium when they had at least one positive CAM-ICU screening or haloperidol administration due to sedation. To validate the PRE-DELIRIC model, we calculated the area under receiver operating characteristic curve.

Results

The mean age of the patients was 69.2 ± 17.2 years, 19 (50%) were male, APACHE-II mean score 18.0 ± 7.4 points. Delirium was diagnosed in 22 (58%) of 38 patients. Data used for validation of the PRE-DELIRIC model resulted in an area under the curve of 0.713 (p < 0.05, 95% CI 0.539-0.887); sensitivity and specificity for the patients with 20% risk were, accordingly, 77.3% and 50%; 40% risk - 45.5% and 81.3%, 60% - 36.4%, and 87.5%.

Conclusions

The PRE-DELIRIC model predicted delirium in the patients within 24 hours of admission to the ICU. Preventive therapy could be efficiently targeted at high-risk patients if both of the methods are to be implemented.

Development and validation of an automated delirium risk assessment system (Auto-DelRAS) implemented in the electronic health record system

BACKGROUND

A key component of the delirium management is prevention and early detection.

OBJECTIVE

To develop an automated delirium risk assessment system (Auto-DelRAS) that automatically alerts health care providers of an intensive care unit (ICU) patient's delirium risk based only on data collected in an electronic health record (EHR) system, and to evaluate the clinical validity of this system.

DESIGN

Cohort and system development designs were used.

SETTING

Medical and surgical ICUs in two university hospitals in Seoul, Korea.

PARTICIPANTS

A total of 3284 patients for the development of Auto-DelRAS, 325 for external validation, 694 for validation after clinical applications.

METHODS

The 4211 data items were extracted from the EHR system and delirium was measured using CAM-ICU (Confusion Assessment Method for Intensive Care Unit). The potential predictors were selected and a logistic regression model was established to create a delirium risk scoring algorithm to construct the Auto-DelRAS. The Auto-DelRAS was evaluated at three months and one year after its application to clinical practice to establish the predictive validity of the system.

RESULTS

Eleven predictors were finally included in the logistic regression model. The results of the Auto-DelRAS risk assessment were shown as high/moderate/low risk on a Kardex screen. The predictive validity, analyzed after the clinical application of Auto-DelRAS after one year, showed a sensitivity of 0.88, specificity of 0.72, positive predictive value of 0.53, negative predictive value of 0.94, and a Youden index of 0.59.

CONCLUSIONS

A relatively high level of predictive validity was maintained with the Auto-DelRAS system, even one year after it was applied to clinical practice.

A Novel Computerized Test for Detecting and Monitoring Visual Attentional Deficits and Delirium in the ICU

OBJECTIVES

Delirium in the ICU is associated with poor outcomes but is under-detected. Here we evaluated performance of a novel, graded test for objectively detecting inattention in delirium, implemented on a custom-built computerized device (Edinburgh Delirium Test Box-ICU).

DESIGN

A pilot study was conducted, followed by a prospective case-control study.

SETTING

Royal Infirmary of Edinburgh General ICU.

PATIENTS

A pilot study was conducted in an opportunistic sample of 20 patients. This was followed by a validation study in 30 selected patients with and without delirium (median age, 63 yr; range, 23-84) who were assessed with the Edinburgh Delirium Test Box-ICU on up to 5 separate days. Presence of delirium was assessed using the Confusion Assessment Method for the ICU.

MEASUREMENTS AND MAIN RESULTS

The Edinburgh Delirium Test Box-ICU involves a behavioral assessment and a computerized test of attention, requiring patients to count slowly presented lights. Thirty patients were assessed a total of 79 times (n = 31, 23, 15, 8, and 2 for subsequent assessments; 38% delirious). Edinburgh Delirium Test Box-ICU scores (range, 0-11) were lower for patients with delirium than those without at the first (median, 0 vs 9.5), second (median, 3.5 vs 9), and third (median, 0 vs 10.5) assessments (all p < 0.001). An Edinburgh Delirium Test Box-ICU score less than or equal to 5 was 100% sensitive and 92% specific to delirium across assessments. Longitudinally, participants' Edinburgh Delirium Test Box-ICU performance was associated with delirium status.

CONCLUSIONS

These findings suggest that the Edinburgh Delirium Test Box-ICU has diagnostic utility in detecting ICU delirium in patients with Richmond Agitation and Sedation Scale Score greater than -3. The Edinburgh Delirium Test Box-ICU has potential additional value in longitudinally tracking attentional deficits because it provides a range of scores and is sensitive to change.

Perioperative Management of Neurological Conditions

Perioperative care of the patients with neurological diseases can be challenging. Most important consideration is the management and understanding of pathophysiology of these disorders and evaluation of new neurological changes that occur perioperatively. Perioperative generally refers to 3 phases of surgery: preoperative, intraoperative, and postoperative. We have tried to address few commonly encountered neurological conditions in clinical practice, such as delirium, stroke, epilepsy, myasthenia gravis, and Parkinson disease. In this article, we emphasize on early diagnosis and management strategies of neurological disorders in the perioperative period to minimize morbidity and mortality of patients.

Delirium in the intensive care setting: A reevaluation of the validity of the CAM-ICU and ICDSC versus the DSM-IV-TR in determining a diagnosis of delirium as part of the daily clinical routine

BACKGROUND

In the intensive care setting, delirium is a common occurrence that comes with subsequent adversities. Therefore, several instruments have been developed to screen for and detect delirium. Their validity and psychometric properties, however, remain controversial.

METHOD

In this prospective cohort study, the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) and the Intensive Care Delirium Screening Checklist (ICDSC) were evaluated versus the DSM-IV-TR in the diagnosis of delirium with respect to their validity and psychometric properties.

RESULTS

Out of some 289 patients, 210 with matching CAM-ICU, ICDSC, and DSM-IV-TR diagnoses were included. Between the scales, the prevalence of delirium ranged from 23.3% with the CAM-ICU, to 30.5% with the ICDSC, to 43.8% with the DSM-IV-TR criteria. The CAM-ICU showed only moderate concurrent validity (Cohen's κ = 0.44) and sensitivity (50%), but high specificity (95%). The ICDSC also reached moderate agreement (Cohen's κ = 0.60) and sensitivity (63%) while being very specific (95%). Between the CAM-ICU and the ICDSC, the concurrent validity was again only moderate (Cohen's κ = 0.56); however, the ICDSC yielded higher sensitivity and specificity (78 and 83%, respectively).

SIGNIFICANCE OF RESULTS

In the daily clinical routine, neither the CAM-ICU nor the ICDSC, common tools used in screening and detecting delirium in the intensive care setting, reached sufficient concurrent validity; nor did they outperform the DSM-IV-TR diagnostic criteria with respect to sensitivity or positive prediction, but they were very specific. Thus, the non-prediction by the CAM-ICU or ICDSC did not refute the presence of delirium. Between the CAM-ICU and ICDSC, the ICDSC proved to be the more accurate instrument.

Impact of remote ischaemic preconditioning on cerebral oxygenation during total knee arthroplasty

Background: Ischaemic reperfusion injury (IRI) after tourniquet release during total knee arthroplasty (TKR) is related to postoperative cerebral complications. Remote ischaemic preconditioning (RIPC) is known to minimise IRI in previous studies. Thus, we evaluated the effect of RIPC on regional cerebral oxygenation after tourniquet release during TKR. Methods: Patients undergoing TKR were randomly allocated to not receive RIPC (control group) and to receive RIPC (RIPC group). Regional cerebral oxygenation and pulmonary oxygenation were assessed up to 24 h postoperatively. The changes in serum cytokine and lactate dehydrogenase (LDH) levels were assessed and arterial blood gas analysis was performed. Total transfusion amounts and postoperative bleeding were also examined. Results: In total, 72 patients were included in the final analysis. Regional cerebral oxygenation (P < 0.001 in the left side, P = 0.003 in the right side) with pulmonary oxygenation (P = 0.001) was significantly higher in the RIPC group. The serum LDH was significantly lower in the RIPC group at 1 h and 24 h postoperatively (P < 0.001). The 24 h postoperative transfusion (P = 0.002) and bleeding amount (P < 0.001) were significantly lower in the RIPC group. Conclusions: RIPC increased cerebral oxygenation after tourniquet release during TKR by improving pulmonary oxygenation. Additionally, RIPC decreased the transfusion and bleeding amount with the serum LDH level.

Music intervention during daily weaning trials-A 6 day prospective randomized crossover trial

PURPOSE

To examine the effect of patient-selected music intervention during daily weaning trials for patients on prolonged mechanical ventilation.

METHODS

Using a crossover repeated measures design, patients were randomized to music vs no music on the first intervention day. Provision of music was alternated for 6 days, resulting in 3 music and 3 no music days. During weaning trials on music days, data were obtained for 30min prior to music listening and continued for 60min while patients listened to selected music (total 90min). On no music days, data were collected for 90min. Outcome measures were heart rate (HR), respiratory rate (RR), oxygen saturation (SpO₂), blood pressure (BP), dyspnea and anxiety assessed with a visual analog scale (VAS-D, VAS-A) and weaning duration (meanh per day on music and non-music days).

RESULTS

Of 31 patients randomized, 23 completed the 6-day intervention. When comparisons were made between the 3 music and 3 no music days, there were significant decreases in RR and VAS-D and a significant increase in daily weaning duration on music days (p<0.05). A multivariate mixed-effects model analysis that included patients who completed ≥2 days of the intervention (n=28) demonstrated significant decreases in HR, RR, VAS-A, and VAS-D and a significant increase in daily weaning duration on music days (p<0.05).

CONCLUSIONS

Providing patient selected music during daily weaning trials is a simple, low-cost, potentially beneficial intervention for patients on prolonged mechanical ventilation. Further study is indicated to test ability of this intervention to promote weaning success and benefits earlier in the weaning process.

Triggers and nursing influences on delirium in intensive care units

Among care providers, nurses have the most influence on the occurrence of delirium in patients. To identify and investigate the risk factors associated with delirium and analyse the nurse's influence on delirium, a secondary data analysis approach was used with clinical data from the electronic medical record and health care provider data from the management information systems of a university hospital. Data of 3284 patients (delirium = 688, non-delirium = 2596) hospitalized in the medical and surgical intensive care units containing 2178 variables were analysed. Donabedian's structure-process-outcome model was applied to categorize the factors for multilevel hierarchical logistic regression analysis. Sixteen factors (10 patient factors, 1 provider factor, 1 environmental factor, 2 nursing intervention factors and 2 medical intervention factors) were identified as significant in the final model. Longer intensive care unit experience of nurses did not decrease the risk of delirium. Greater number of nursing intervention needs and greater use of restraints were associated with an increased risk of delirium. The duration of nursing career did not affect the reduction of the risk of delirium. Nurses should therefore endeavour to acquire nursing experience specific for delirium care and attend training courses for delirium management.

Current approach to diagnosis and treatment of delirium after cardiac surgery

Delirium after cardiac surgery remains a common occurrence that results in significant short- and long-term morbidity and mortality. It continues to be underdiagnosed given its complex presentation and multifactorial etiology; however, its prevalence is increasing given the aging cardiac surgical population. This review highlights the perioperative risk factors, tools to assist in diagnosing delirium, and current pharmacological and nonpharmacological therapy options.

Detection of Delirium in Hospitalized Older General Medicine Patients: A Comparison of the 3D-CAM and CAM-ICU

BACKGROUND

Delirium is common in older hospitalized patients and is associated with poor outcomes, yet most cases go undetected. The best approach for systematic delirium identification outside the intensive care unit remains unknown.

OBJECTIVE

To conduct a comparative effectiveness study of the Confusion Assessment Method for the ICU (CAM-ICU) and the newly developed 3-minute diagnostic assessment for delirium using the Confusion Assessment Method (3D-CAM) in general medicine inpatients.

DESIGN

Cross-sectional comparative effectiveness study.

SETTING

Two non-intensive care general medicine units at a single academic medical center.

PARTICIPANTS

Hospitalized general medicine patients aged ≥75 years.

MEASUREMENTS

Clinicians performed a reference standard assessment for delirium that included patient interviews, family interviews, and review of the medical record. An expert panel determined the presence or absence of delirium using DSM-IV criteria. Two blinded research assistants administered the CAM-ICU and the 3D-CAM in random order, and we determined their diagnostic test characteristics compared to the reference standard.

RESULTS

Among the 101 participants (mean age 84 ± 5.5 years, 61 % women, 25 % with dementia), 19 % were classified as delirious based on the reference standard. Evaluation times for the 3D-CAM and CAM-ICU were similar. The sensitivity [95 % confidence interval (CI)] of delirium detection for the 3D-CAM was 95 % [74 %, 100 %] and for the CAM-ICU was 53 % [29 %, 76 %], while specificity was >90 % for both instruments. Subgroup analyses showed that the CAM-ICU had sensitivity of 30 % in patients with mild delirium vs. 100 % for the 3D-CAM.

CONCLUSIONS

In this comparative effectiveness study, we found that the 3D-CAM had substantially higher sensitivity than the CAM-ICU in hospitalized older general medicine patients, and similar administration time. Therefore, the 3D-CAM may be a superior screening tool for delirium in this patient population.

Postoperative Delirium in Elderly Patients Undergoing Hip Fracture Surgery in the Sugammadex Era: A Retrospective Study

Background. Residual neuromuscular block (NMB) after general anesthesia has been associated with pulmonary dysfunction and hypoxia, which are both associated with postoperative delirium (POD). We evaluated the effects of sugammadex on POD in elderly patients who underwent hip fracture surgery. Methods. Medical records of 174 consecutive patients who underwent hip fracture surgery with general anesthesia were reviewed retrospectively to compare the perioperative incidence of POD, pulmonary complications, time to extubation, incidence of hypoxia, and laboratory findings between patients treated with sugammadex and those treated with a conventional cholinesterase inhibitor. Results. The incidence of POD was not significantly different between the two groups (33.3% versus 36.5%, resp.; P = 0.750). Postoperative pulmonary complications and laboratory findings did not showed significant intergroup difference. However, time to extubation (6 ± 3 versus 8 ± 3 min; P < 0.001) and the frequency of postoperative hypoxia were significantly lower (23% versus 43%; P = 0.010) in the sugammadex group than in the conventional cholinesterase inhibitor group. Conclusion. Sugammadex did not reduce POD or pulmonary complications compared to conventional cholinesterase inhibitors, despite reducing time to extubation and postoperative hypoxia in elderly patients who underwent hip fracture surgery under general anesthesia.

Delirium after surgical and transcatheter aortic valve replacement is associated with increased mortality

OBJECTIVE

The purpose of this study was to determine the incidence and clinical significance of postoperative delirium (PD) in patients with aortic stenosis undergoing surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR).

METHOD

Between 2010 and 2013, 427 patients underwent TAVR (n = 168) or SAVR (n = 259) and were screened for PD using the Confusion Assessment Method for the Intensive Care Unit. The incidence of PD in both treatment groups was determined and its association with morbidity and mortality was retrospectively compared.

RESULTS

PD occurred in 135 patients (32%) with a similar incidence between SAVR (33% [86 out of 259]) and TAVR (29% [49 out of 168]) (P = .40). TAVR by transfemoral approach had the lowest incidence of PD compared with SAVR (18% vs 33%; P = .025) or TAVR when performed by alternative access techniques (18% vs 35%; P = .02). Delirium was associated with longer initial intensive care unit stay (70 vs 27 hours), intensive care unit readmission (10% [14 out of 135] vs 2% [6 out of 292]), and longer hospital stay (8 vs 6 days) (P < .001 for all). PD was associated with increased mortality at 30 days (7% vs 1%; P < .001) and 1 year (21% vs 8%; P < .001). After multivariable adjustment, PD remained associated with increased 1-year mortality (hazard ratio, 3.02; 95% confidence interval, 1.75-5.23; P < .001). There was no interaction between PD and aortic valve replacement approach with respect to 1-year mortality (P = .12). Among propensity-matched patients (n = 170), SAVR-treated patients had a higher incidence of PD than TAVR-treated patients (51% vs 29%; P = .004).

CONCLUSIONS

PD occurs commonly after SAVR and TAVR and is associated with increased morbidity and mortality. Given the high incidence of PD and its associated adverse outcomes, further studies are needed to minimize PD and potentially improve patient outcomes.

Aspects and assessment of delirium in old age. First data from a German interdisciplinary emergency department

BACKGROUND

The prevalence of delirium in hospitalized patients is high, but delirium is frequently not identified by treating physicians in emergency departments (EDs). Although the number of elderly patients admitted to EDs is increasing, no data on prevalence, identification and outcome of delirious elderly patients in German EDs exist.

OBJECTIVES

To evaluate the prevalence and identification of delirium in elderly patients in a German ED and to identify characteristics of delirium in elderly ED patients.

METHODS

Evaluation of data from a prospective single-center observational study. The study was conducted in the interdisciplinary ED of an urban university-affiliated hospital receiving approximately 80,000 visits per year. The shortened Confusion Assessment Method (CAM) was used to screen 133 consecutive ED patients, aged 75 years and older, for delirium. Comorbid conditions were ascertained by patient interview and review of medical records. Data concerning patient mortality and current living status were collected 28 days after the ED visit in a structured telephone interview.

RESULTS

A positive CAM result was recorded in 14.3 % of cases; 68.4 % of these CAM-positive patients were not identified as being delirious by the ED physician. The 28-day mortality was higher among patients with delirium. Dependency on external help, polypharmacy, pre-existing cognitive or mobility impairments and the presence of any care level were strongly associated with delirium.

CONCLUSION

Elderly patients with known risk factors should be routinely assessed for delirium in the ED with a standardized assessment tool such as the CAM.

The confusion assessment method for the intensive care unit in patients with cirrhosis

In the intensive care unit (ICU), delirium is routinely measured with the widely-used, validated Confusion Assessment Method for the ICU (CAM-ICU), but CAM-ICU has not been studied in patients with cirrhosis. We studied a group of patients with cirrhosis to determine the relationship between delirium measured by CAM-ICU and clinical outcomes. Consecutive patients with cirrhosis admitted to the ICU from 2009 to 2012 were included in a retrospective cohort study. Patients were screened twice daily for coma and delirium during their ICU stay using the Richmond Agitation Sedation Scale (RASS) and CAM-ICU. The association between delirium/coma and mortality was determined using multiple logistic regression. RASS and CAM-ICU were also compared to a retrospective assessment of hepatic encephalopathy (HE). Of 91 patients with cirrhosis, 26 (28.6 %) developed delirium/coma. RASS/CAM-ICU had fair agreement with the HE assessment (κ 0.38). Patients with delirium/coma had numerically greater mortality in-hospital (23.1 vs. 7.7 %, p = 0.07) and at 90 days (30.8 vs. 18.5 %, p = 0.26), and they also had longer hospital length of stay (median 19.5 vs. 6 days, p < 0.001). Delirium/coma was associated with increased inpatient mortality, independent of disease severity (unadjusted OR 3.6; 95 % CI, 0.99-13.1; MELD-adjusted OR 5.4; 95 % CI, 1.3-23.8; acute physiology score-adjusted OR 2.2; 95 % CI, 0.53-8.9). Delirium/coma was also associated with longer length of stay after adjusting for disease severity. In critically ill patients with cirrhosis, delirium/coma as measured by the RASS and CAM-ICU is associated with increased mortality and hospital length of stay. For these patients, these measures provide valuable information and may be useful tools for clinical care. RASS and CAM-ICU need to be compared to HE-specific measures in future studies.

Validation study of the European Portuguese version of the Confusion Assessment Method (CAM)

BACKGROUND

The Confusion Assessment Method (CAM) is the most widely used delirium screening instrument. The aim of this study was to evaluate the reliability and validity of the European Portuguese version of CAM.

METHODS

The sample included elderly patients (≥65 years), admitted for at least 48 h, into two intermediate care units (ICMU) of Intensive Medicine and Surgical Services in a university hospital. Exclusion criteria were: score ≤11 on the Glasgow Coma Scale (GCS), blindness/deafness, inability to communicate and to speak Portuguese. For concurrent validity, a blinded assessment was conducted by a psychiatrist (DSM-IV-TR, as a reference standard) and by a trained researcher (CAM). This instrument was also compared with other cognitive measures to evaluate convergent validity. Inter-rater reliability was also assessed.

RESULTS

In this sample (n = 208), 25% (n = 53) of the patients had delirium, according to DSM-IV-TR. Using this reference standard, the CAM had a moderate sensitivity of 79% and an excellent specificity of 99%. The positive predictive value was 95%, indicating a strong ability to confirm delirium with a positive test result, and the negative predictive value was lower (93%). Good convergent validity was also found, in particular with Mini-Mental State Examination (MMSE) (rs = -0.676; p ≤0.01) and Digit Span Test (DST) forward (rs = -0.605; p ≤0.01), as well as a high inter-rater reliability (diagnostic k = 1.00; single items' k between 0.65 and 1.00).

CONCLUSION

Robust results on concurrent and convergent validity and good reliability were achieved. This version was shown to be a valid and reliable instrument for delirium detection in elderly patients hospitalized in intermediate care units.

Clinical neurophysiological assessment of sepsis-associated brain dysfunction: a systematic review

Introduction

Several studies have reported the presence of electroencephalography (EEG) abnormalities or altered evoked potentials (EPs) during sepsis. However, the role of these tests in the diagnosis and prognostic assessment of sepsis-associated encephalopathy remains unclear.

Methods

We performed a systematic search for studies evaluating EEG and/or EPs in adult (≥18 years) patients with sepsis-associated encephalopathy. The following outcomes were extracted: a) incidence of EEG/EP abnormalities; b) diagnosis of sepsis-associated delirium or encephalopathy with EEG/EP; c) outcome.

Results

Among 1976 citations, 17 articles met the inclusion criteria. The incidence of EEG abnormalities during sepsis ranged from 12% to 100% for background abnormality and 6% to 12% for presence of triphasic waves. Two studies found that epileptiform discharges and electrographic seizures were more common in critically ill patients with than without sepsis. In one study, EEG background abnormalities were related to the presence and the severity of encephalopathy. Background slowing or suppression and the presence of triphasic waves were also associated with higher mortality. A few studies demonstrated that quantitative EEG analysis and EP could show significant differences in patients with sepsis compared to controls but their association with encephalopathy and outcome was not evaluated.

Conclusions

Abnormalities in EEG and EPs are present in the majority of septic patients. There is some evidence to support EEG use in the detection and prognostication of sepsis-associated encephalopathy, but further clinical investigation is needed to confirm this suggestion.

3D-CAM: derivation and validation of a 3-minute diagnostic interview for CAM-defined delirium: a cross-sectional diagnostic test study

BACKGROUND

Delirium is common, leads to other adverse outcomes, and is costly. However, it often remains unrecognized in most clinical settings. The Confusion Assessment Method (CAM) is the most widely used diagnostic algorithm, and operationalizing its features would be a substantial advance for clinical care.

OBJECTIVE

To derive the 3D-CAM, a new 3-minute diagnostic assessment for CAM-defined delirium, and validate it against a clinical reference standard.

DESIGN

Derivation and validation study.

SETTING

4 general medicine units in an academic medical center.

PARTICIPANTS

201 inpatients aged 75 years or older.

MEASUREMENTS

20 items that best operationalized the 4 CAM diagnostic features were identified to create the 3D-CAM. For prospective validation, 3D-CAM assessments were administered by trained research assistants. Clinicians independently did an extensive assessment, including patient and family interviews and medical record reviews. These data were considered by an expert panel to determine the presence or absence of delirium and dementia (reference standard). The 3D-CAM delirium diagnosis was compared with the reference standard in all patients and subgroups with and without dementia.

RESULTS

The 201 participants in the prospective validation study had a mean age of 84 years, and 28% had dementia. The expert panel identified 21% with delirium, 88% of whom had hypoactive or normal psychomotor features. Median administration time for the 3D-CAM was 3 minutes (interquartile range, 2 to 5 minutes), sensitivity was 95% (95% CI, 84% to 99%), and specificity was 94% (CI, 90% to 97%). The 3D-CAM did well in patients with dementia (sensitivity, 96% [CI, 82% to 100%]; specificity, 86% [CI, 67% to 96%]) and without dementia (sensitivity, 93% [CI, 66% to 100%]; specificity, 96% [CI, 91% to 99%]).

LIMITATION

Limited to single-center, cross-sectional, and medical patients only.

CONCLUSION

The 3D-CAM operationalizes the CAM algorithm using a 3-minute structured assessment with high sensitivity and specificity relative to a reference standard and could be an important tool for improving recognition of delirium.

PRIMARY FUNDING SOURCE

National Institute on Aging.

Neurological complications of surgery and anaesthesia

Injury to the central and peripheral nervous systems is often permanent. As such, adverse neurological outcomes of surgery and anaesthesia can be devastating for patients and their families. In this article, we review the incidence, risk factors, outcomes, prevention, and treatment of a number of important neurological complications in the perioperative period.

Automatic Delirium Prediction System and Nursing-Sensitive Outcomes in the Medical Intensive Care Unit

In Korea, delirium risk screening has not been routinely implemented in intensive care units (ICUs). The purpose of this study was to implement an Automatic Prediction of Delirium in Intensive Care Units (APREDEL-ICU) system to investigate its impact on nursing-sensitive outcomes and to assess nurse satisfaction with the system. A pre–post research design was used. A total of 145 patients were involved prior to the system implementation and 172 were involved after implementation. Forty medical ICU nurses evaluated the system. The APREDEL-ICU system did not result in a reduction in the incidence of delirium. However, the nurses reported that their knowledge regarding delirium care increased after the system was introduced. The proposed system was successfully implemented without increasing the burden of nurses in their assessment of delirium risk. Long-term use of APREDEL-ICU could enhance preventive care and consequently result in positive patient outcomes.

Improving delirium care: prevention, monitoring, and assessment

Delirium is an acute change in awareness and attention and is common, morbid, and costly for patients and health care systems. While hyperactive delirium is easily identifiable, the hypoactive form is more common and carries a higher mortality. Hospital systems to address delirium should consist of 3 critical steps. First, hospitals must identify patients who develop or are at intermediate or high risk for delirium. Delirium risk may be assessed using known patient-based and illness-based risk factors, including preexisting cognitive impairment. Delirium diagnosis remains a clinical diagnosis that requires a clinical assessment that can be structured using diagnostic criteria. Hospital systems may be useful to efficiently allocate delirium resources to prevent and manage delirium. Second, it is crucial to develop a systematic approach to prevent delirium using multimodal nonpharmacologic delirium prevention methods and to monitor all high-risk patients for its occurrence. Tools such as the modified Richmond Agitation and Sedation Scale can aid in monitoring for changes in mental status that could indicate the development of delirium. Third, hospital systems can utilize established methods to assess and manage delirium in a standardized fashion. The key lies in addressing the underlying cause/causes of delirium, which often involve medical conditions or medications. With a sustained commitment, standardized efforts to identify and prevent delirium can mitigate the long-term morbidity associated with this acute change. In the face of changes in health care funding, delirium serves as an example of a syndrome where care coordination can improve short-term and long-term costs.

Delirium prevalence, incidence, and implications for screening in specialist palliative care inpatient settings: a systematic review

BACKGROUND

Delirium is a serious neuropsychiatric syndrome frequently experienced by palliative care inpatients. This syndrome is under-recognized by clinicians. While screening increases recognition, it is not a routine practice.

AIM AND DESIGN

This systematic review aims to examine methods, quality, and results of delirium prevalence and incidence studies in palliative care inpatient populations and discuss implications for delirium screening.

DATA SOURCES

A systematic search of the literature identified prospective studies reporting on delirium prevalence and/or incidence in inpatient palliative care adult populations from 1980 to 2012. Papers not in English or those reporting the occurrence of symptoms not specifically identified as delirium were excluded.

RESULTS

Of the eight included studies, the majority (98.9%) involved participants (1079) with advanced cancer. Eight different screening and assessment tools were used. Delirium incidence ranged from 3% to 45%, while delirium prevalence varied, with a range of: 13.3%-42.3% at admission, 26%-62% during admission, and increasing to 58.8%-88% in the weeks or hours preceding death. Studies that used the Diagnostic and Statistical Manual-Fourth Edition reported higher prevalence (42%-88%) and incidence (40.2%-45%), while incidence rates were higher in studies that screened participants at least daily (32.8%-45%). Hypoactive delirium was the most prevalent delirium subtype (68%-86% of cases).

CONCLUSION

The prevalence and incidence of delirium in palliative care inpatient settings supports the need for screening. However, there is limited consensus on assessment measures or knowledge of implications of delirium screening for inpatients and families. Further research is required to develop standardized methods of delirium screening, assessment, and management that are acceptable to inpatients and families.

Delirium in postoperative nonventilated intensive care patients: risk factors and outcomes

Background

Delirium features can vary greatly depending on the postoperative population studied; however, most studies focus only on high-risk patients. Describing the impact of delirium and risk factors in mixed populations can help in the development of preventive actions.

Methods

The occurrence of delirium was evaluated prospectively in 465 consecutive nonventilated postoperative patients admitted to a surgical intensive care unit (SICU) using the confusion assessment method (CAM). Patients with and without delirium were compared. A multiple logistic regression was performed to identify the main risk factors for delirium in the first 24 h of admission to the SICU and the main predictors of outcomes.

Results

Delirium was diagnosed in 43 (9.2%) individuals and was more frequent on the second and third days of admission. The presence of delirium resulted in longer lengths of SICU and hospital stays [6 days (3–13) vs. 2 days (1–3), p < 0.001 and 26 days (12–39) vs. 6 days (3–13), p <0.001, respectively], as well as higher hospital and SICU mortality rates [16.3% vs. 4.0%, p = 0.004 and 6.5% vs. 1.7%, p = 0.042, respectively]. The risk factors for delirium were age (odds ratio (OR), 1.04 [1.02-1.07]), Acute Physiologic Score (APS; OR, 1.11 [1.04-1.2]), emergency surgery (OR, 8.05 [3.58-18.06]), the use of benzodiazepines (OR, 2.28 [1.04-5.00]), and trauma (OR, 6.16 [4.1-6.5]).

Conclusions

Delirium negatively impacts postoperative nonventilated patients. Risk factors can be used to detect high-risk patients in a mixed population of SICU patients.