Rivastigmine for the prevention of postoperative delirium in elderly patients undergoing elective cardiac surgery--a randomized controlled trial. Crit Care Med. 2009;37:1762-1768. [PMID: 19325490 DOI: 10.1097/CCM.0b013e31819da780]

Characteristics associated with effectiveness in postoperative delirium research: a systematic review of randomised controlled trials with meta-regression and meta-analysis

BACKGROUND

Postoperative delirium remains prevalent despite extensive research through randomised trials aimed at reducing its incidence. Understanding trial characteristics associated with interventions' effectiveness facilitates data interpretation.

METHODS

Trial characteristics were extracted from eligible trials identified through two systematic literature searches. Multivariable meta-regression was used to investigate trial characteristics associated with effectiveness estimated using odds ratios. Meta-analysis was used to investigate pooled effectiveness.

RESULTS

We identified 201 eligible trials. Compared with China, trials from the USA/Canada (ratio of odds ratio, 1.89; 95% confidence interval, 1.45-2.45) and Europe/Australia/New Zealand (1.67; 1.29-2.18) had an 89% and 67% higher odds ratio, respectively, suggesting reduced effectiveness. The effectiveness was enhanced when the incidence of postoperative delirium increased (0.85; 0.79-0.92, per 10% increase). Trials with concerns related to deviations from intended interventions reported increased effectiveness compared with those at low risk (0.69; 0.53-0.90). Compared with usual care, certain interventions appeared to have reduced the incidence of postoperative delirium in low-risk trials with low-to-moderate certainty of evidence. However, these findings should be considered inconclusive because of challenges in grouping heterogeneous interventions, the limited number of eligible trials, the prevalence of small-scale studies, and potential publication bias.

CONCLUSIONS

The effectiveness of postoperative delirium trials varied based on the region of trial origin, the incidence of delirium, and the risk of bias. The limitations caution against drawing definitive conclusions from different bodies of evidence. These findings highlight the imperative need to improve the quality of research on a global scale.

SYSTEMATIC REVIEW PROTOCOL

PROSPERO (CRD42023413984).

Prevention of post-operative delirium using an overnight infusion of dexmedetomidine in patients undergoing cardiac surgery: a pragmatic, randomized, double-blind, placebo-controlled trial

BACKGROUND

After cardiac surgery, post-operative delirium (PoD) is acknowledged to have a significant negative impact on patient outcome. To date, there is no valuable and specific treatment for PoD. Critically ill patients often suffer from poor sleep condition. There is an association between delirium and sleep quality after cardiac surgery. This study aimed to establish whether promoting sleep using an overnight infusion of dexmedetomidine reduces the incidence of delirium after cardiac surgery.

METHODS

Randomized, pragmatic, multicentre, double-blind, placebo controlled trial from January 2019 to July 2021. All adult patients aged 65 years or older requiring elective cardiac surgery were randomly assigned 1:1 either to the dexmedetomidine group or the placebo group on the day of surgery. Dexmedetomidine or matched placebo infusion was started the night after surgery from 8 pm to 8 am and administered every night while the patient remained in ICU, or for a maximum of 7 days. Primary outcome was the occurrence of postoperative delirium (PoD) within the 7 days after surgery.

RESULTS

A total of 348 patients provided informed consent, of whom 333 were randomized: 331 patients underwent surgery and were analysed (165 assigned to dexmedetomidine and 166 assigned to placebo). The incidence of PoD was not significantly different between the two groups (12.6% vs. 12.4%, p = 0.97). Patients treated with dexmedetomidine had significantly more hypotensive events (7.3% vs 0.6%; p < 0.01). At 3 months, functional outcomes (Short-form 36, Cognitive failure questionnaire, PCL-5) were comparable between the two groups.

CONCLUSION

In patients recovering from an elective cardiac surgery, an overnight infusion of dexmedetomidine did not decrease postoperative delirium. Trial registration This trial was registered on ClinicalTrials.gov (number: NCT03477344; date: 26th March 2018).

Ramelteon and suvorexant for postoperative delirium in elderly patients with esophageal cancer

BACKGROUND

There is no clear evidence on the prevention of postoperative delirium with pharmacotherapy in elderly patients with esophageal cancer. This retrospective study aimed to evaluate the efficacy of ramelteon and suvorexant in preventing postoperative delirium in this patient group.

METHODS

Data on 251 patients who received radical esophagectomy for thoracic esophageal cancer were collected from January 2010 to September 2021. In total, 74 patients did not receive preventive intervention, and 177 received ramelteon and suvorexant. After propensity score matching, the rate of postoperative delirium was compared between the two groups.

RESULTS

Seventy-two well-balanced patients in each group demonstrated similar clinical and pathological characteristics. The mean ages of the intervention and control groups were 70.8 and 70.3 years, respectively. All the patients underwent McKeown esophagectomy, and in the volume of intraoperative blood loss or operative time did not significantly differ between the two groups. The incidence rates of postoperative hyperactive delirium were 7% (5/72) in the intervention group and 32% (23/72) in the control group (p < 0.001). No severe adverse event potentially attributable to the intervention drug was observed. The multivariate analysis showed that the use of ramelteon and suvorexant was the only independent protective factor against postoperative delirium (hazard ratio 0.157, 95% CI 0.055-0.448, p < 0.001).

CONCLUSIONS

Ramelteon and suvorexant may play an important role in reducing postoperative delirium in elderly patients with esophageal cancer.

Preventing and treating delirium in clinical settings for older adults

Delirium is a serious consequence of many acute or worsening chronic medical conditions, a side effect of medications, and a precipitant of worsening functional and cognitive status in older adults. It is a syndrome characterized by fluctuations in cognition and impaired attention that develops over a short period of time in response to an underlying medical condition, a substance (prescribed, over the counter, or recreational), or substance withdrawal and can be multi-factorial. We present a narrative review of the literature on nonpharmacologic and pharmacologic approaches to prevention and treatment of delirium with a focus on older adults as a vulnerable population. Older adult patients are most at risk due to decreasing physiologic reserves, with delirium rates of up to 80% in critical care settings. Presentation of delirium can be hyperactive, hypoactive, or mixed, making identification and study challenging as patients with hypoactive delirium are less likely to come to attention in an inpatient or long-term care setting. Studies of delirium focus on prevention and treatment with nonpharmacological or medication interventions, with the preponderance of evidence favoring multi-component nonpharmacological approaches to prevention as the most effective. Though use of antipsychotic medication in delirium is common, existing evidence does not support routine use, showing no clear benefit in clinically significant outcome measures and with evidence of harm in some studies. We therefore suggest that antipsychotics be used to treat agitation, psychosis, and distress associated with delirium at the lowest effective doses and shortest possible duration and not be considered a treatment of delirium itself. Future studies may clarify the use of other agents, such as melatonin and melatonin receptor agonists, alpha-2 receptor agonists, and anti-epileptics.

The impact of rivastigmine on post-surgical delirium and cognitive impairment; a randomized clinical trial

BACKGROUND

Delirium is an acute and transient disorder of brain function that often occurs in post-surgical patients. Rivastigmine is a cholinesterase inhibitor drug that has been proposed as an adjuvant drug in recent years, still, despite significant theoretical evidence, few clinical studies have been performed on its impact on delirium.

AIM

Due to the widespread use of cholinesterase inhibitors in pediatric and adult surgery, the present study aims to investigate the impact of Rivastigmine as a cholinesterase inhibitor on delirium after radical surgery.

METHODS

In this randomized double-blind clinical trial, a hundred recruited patients were randomly assigned to either Rivastigmine (n = 50) or placebo (n = 50) groups, and we measured post-operative impact on delirium, by Confusion Assessment Method (CAM) score, and cognitive impairment, by the Mini-Mental State Examination (MMSE). Our univariate and multivariate logistical regression models assessed this hypothesized impact.

RESULTS

Treatment with Rivastigmine was significantly associated with reduced day one post-op delirium, as measured by CAM score (Odds Ratio (OR) = 0.35, 95% Confidence Interval (CI) 0.11 to 0.97, p = 0.05), and cognitive impairment, as measured by MMSE (OR = 0.25, 95% CI 0.1 to 0.59, p = 0.0022). These associations became stronger after controlling for age, blood loss, and post-op blood sodium levels: Delirium (OR = 0.23, 95% CI 0.05 to 0.92, p = 0.05), cognitive impairment (OR = 0.12, 95% CI 0.03 to 0.42, p = 0.000178).

CONCLUSION

The significant result of our randomized clinical trial is that pre-op Rivastigmine treatment may be associated with a substantial drop in patients experiencing post-op delirium and post-op cognitive impairment.

Perioperative Neurocognitive Disorders in Adults Requiring Cardiac Surgery: Screening, Prevention, and Management

Neurocognitive changes are the most common complication after cardiac surgery, ranging from acute postoperative delirium to prolonged postoperative neurocognitive disorder. Changes in cognition are distressing to patients and families and associated with worse outcomes overall. This review outlines definitions and diagnostic criteria, risk factors for, and mechanisms of Perioperative Neurocognitive Disorders and offers strategies for preoperative screening and perioperative prevention and management of neurocognitive complications.

Delirium Prevention and Management in Frail Surgical Patients

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

Pharmacological prevention of postoperative delirium in patients undergoing cardiac surgery: a bayesian network meta-analysis

The incidence of postoperative delirium in patients undergoing cardiac surgery is very high and increases morbidity and mortality. The possibility of pharmacological means to reduce its incidence is very attractive. At present, there is still no clear demonstration that any drug can prevent postoperative delirium in these patients. The aim of this Bayesian network meta-analysis (NMA) was to evaluate whether there is evidence that a drug is effective in reducing the incidence of POD in cardiac surgical patients. Our NMA showed that preoperative ketamine at subanesthetic doses can significantly reduce the incidence of POD. Risperidone also decreases the incidence of POD, but not significantly.

Increased Enzymatic Activity of Acetylcholinesterase Indicates the Severity of the Sterile Inflammation and Predicts Patient Outcome following Traumatic Injury

Traumatic injury induces sterile inflammation, an immune response often associated with severe organ dysfunction. The cholinergic system acts as an anti-inflammatory in injured patients. Acetylcholinesterase (AChE), an enzyme responsible for the hydrolysis of acetylcholine, plays an essential role in controlling cholinergic activity. We hypothesized that a change in the AChE activity might indicate the severity of the traumatic injury. This study included 82 injured patients with an Injury Severity Score (ISS) of 4 or above and 40 individuals without injuries. Bedside-measured AChE was obtained on hospital arrival, followed by a second measurement 4-12 h later. C-reactive protein (CRP), white blood cell count (WBCC), and Sequential Organ Failure Assessment (SOFA) score were simultaneously collected. Injured patients showed an early and sustained increase in AChE activity. CRP remained unaffected at hospital admission and increased subsequently. Initially elevated WBCC recovered 4-12 h later. AChE activity directly correlated with the ISS and SOFA scores and predicted the length of ICU stay when measured at hospital admission. An early and sustained increase in AChE activity correlated with the injury severity and could predict the length of ICU stay in injured patients, rendering this assay a complementary diagnostic and prognostic tool at the hand of the attending clinician in the emergency unit.

Surgical Pharmacy for Optimizing Medication Therapy Management Services within Enhanced Recovery after Surgery (ERAS®) Programs

Drug-related problems (DRPs) are common among surgical patients, especially older patients with polypharmacy and underlying diseases. DRPs can potentially lead to morbidity, mortality, and increased treatment costs. The enhanced recovery after surgery (ERAS) system has shown great advantages in managing surgical patients. Medication therapy management for surgical patients (established as "surgical pharmacy" by Guangdong Province Pharmaceutical Association (GDPA)) is an important part of the ERAS system. Improper medication therapy management can lead to serious consequences and even death. In order to reduce DRPs further, and promote the rapid recovery of surgical patients, the need for pharmacists in the ERAS program is even more pressing. However, the medication therapy management services of surgical pharmacy and how surgical pharmacists should participate in ERAS programs are still unclear worldwide. Therefore, this article reviews the main perioperative medical management strategies and precautions from several aspects, including antimicrobial agents, antithrombotic agents, pain medication, nutritional therapy, blood glucose monitoring, blood pressure treatment, fluid management, treatment of nausea and vomiting, and management of postoperative delirium. Additionally, the way surgical pharmacists participate in perioperative medication management, and the relevant medication pathways are explored for optimizing medication therapy management services within the ERAS programs. This study will greatly assist surgical pharmacists' work, contributing to surgeons accepting that pharmacists have an important role in the multidisciplinary team, benefitting medical workers in treating, counseling, and advocating for their patients, and further improving the effectiveness, safety and economy of medication therapy for patients and promoting patient recovery.

Statin Use and Delirium Risk: An Updated Systematic Review and Meta-Analysis

BACKGROUND

Findings on the association of statin use with delirium risk are inconsistent.

THE STUDY QUESTION

Is statin use associated with delirium risk?

STUDY DESIGN

We searched PubMed, the Cochrane Library, and the EMBASE database, limiting the search to human patients and articles in English published until December 31, 2021. The effect size and 95% confidence interval (CI) were defined as the odds ratio (OR) and 95% CI, respectively, to indicate the difference in the incidence of delirium between statin use and nonuse groups. A random-effects model was selected in the case of high heterogeneity of study populations. We used funnel plots, Egger test, Duval and Tweedie trim-and-fill approach, and the classic fail-safe N to assess publication bias.

RESULTS

Of a total of 264 identified studies, 13 were selected for the qualitative review-4 RCTs and 9 observational cohort studies. Statin use was not associated with low delirium risk (pooled OR, 0·82; 95% CI, 0·64-1·04; P = 0·09). Substantial statistical heterogeneity was observed (I2, 90%). Visual inspection of the funnel plot of ORs from the studies revealed symmetry. Using the Grading of Recommendations Assessment, Development, and Evaluation approach, we assigned the evidence a rating of C and a weak recommendation for this review.

CONCLUSIONS

Statin use is not associated with delirium risk. More comprehensive RCTs are required to confirm the results.

Dexmedetomidine after Cardiac Surgery for Prevention of Delirium (EXACTUM) trial protocol: a multicentre randomised, double-blind, placebo-controlled trial

INTRODUCTION

Incidence of delirium after cardiac surgery remains high and delirium has a significant burden on short-term and long-term outcomes. Multiple causes can trigger delirium occurence, and it has been hypothesised that sleep disturbances can be one of them. Preserving the circadian rhythm with overnight infusion of low-dose dexmedetomidine has been shown to lower the occurrence of delirium in older patients after non-cardiac surgery. However, these results remain controversial. The aim of this study was to demonstrate the usefulness of sleep induction by overnight infusion of dexmedetomidine to prevent delirium after cardiac surgery.

METHODS AND ANALYSIS

Dexmedetomidine after Cardiac Surgery for Prevention of Delirium is an investigator-initiated, randomised, placebo-controlled, parallel, multicentre, double-blinded trial. Nine centres in France will participate in the study. Patients aged 65 years or older and undergoing cardiac surgery will be enrolled in the study. The intervention starts on day 0 (the day of surgery) until intensive care unit (ICU) discharge; the treatment is administered from 20:00 to 08:00 on the next day. Infusion rate is modified by the treating nurse or the clinician with an objective of Richmond Agitation and Sedation Scale score from -1 to +1. The primary outcome is delirium occurrence evaluated with confusion assessment method for the ICU two times per day during 7 days following surgery. Secondary outcomes include incidence of agitation related events, self-evaluated quality of sleep, cognitive evaluation 3 months after surgery and quality of life 3 months after surgery. The sample size is 348.

ETHICS AND DISSEMINATION

The study was approved for all participating centers by the French Central Ethics Committee (Comité de Protection des Personnes Ile de France VI, registration number 2018-000850-22). The results will be submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT03477344.

Contemporary Neuroprotection Strategies during Cardiac Surgery: State of the Art Review

Open-heart surgery is the leading cause of neuronal injury in the perioperative state, with some patients complicating with cerebrovascular accidents and delirium. Neurological fallout places an immense burden on the psychological well-being of the person affected, their family, and the healthcare system. Several randomised control trials (RCTs) have attempted to identify therapeutic and interventional strategies that reduce the morbidity and mortality rate in patients that experience perioperative neurological complications. However, there is still no consensus on the best strategy that yields improved patient outcomes, such that standardised neuroprotection protocols do not exist in a significant number of anaesthesia departments. This review aims to discuss contemporary evidence for preventing and managing risk factors for neuronal injury, mechanisms of injury, and neuroprotection interventions that lead to improved patient outcomes. Furthermore, a summary of existing RCTs and large observational studies are examined to determine which strategies are supported by science and which lack definitive evidence. We have established that the overall evidence for pharmacological neuroprotection is weak. Most neuroprotective strategies are based on animal studies, which cannot be fully extrapolated to the human population, and there is still no consensus on the optimal neuroprotective strategies for patients undergoing cardiac surgery. Large multicenter studies using universal standardised neurological fallout definitions are still required to evaluate the beneficial effects of the existing neuroprotective techniques.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Delirium and neuropsychological outcomes in critically Ill patients with COVID-19: a cohort study

OBJECTIVE

To characterise the clinical course of delirium for patients with COVID-19 in the intensive care unit, including postdischarge neuropsychological outcomes.

DESIGN

Retrospective chart review and prospective survey study.

SETTING

Intensive care units, large academic tertiary-care centre (USA).

PARTICIPANTS

Patients (n=148) with COVID-19 admitted to an intensive care unit at Michigan Medicine between 1 March 2020 and 31 May 2020 were eligible for inclusion.

PRIMARY AND SECONDARY OUTCOME MEASURES

Delirium was the primary outcome, assessed via validated chart review method. Secondary outcomes included measures related to delirium, such as delirium duration, antipsychotic use, length of hospital and intensive care unit stay, inflammatory markers and final disposition. Neuroimaging data were also collected. Finally, a telephone survey was conducted between 1 and 2 months after discharge to determine neuropsychological function via the following tests: Family Confusion Assessment Method, Short Blessed Test, Patient-Reported Outcomes Measurement Information System Cognitive Abilities 4a and Patient-Health Questionnaire-9.

RESULTS

Delirium was identified in 108/148 (73%) patients, with median (IQR) duration lasting 10 (4-17) days. In the delirium cohort, 50% (54/108) of patients were African American and delirious patients were more likely to be female (76/108, 70%) (absolute standardised differences >0.30). Sedation regimens, inflammation, delirium prevention protocol deviations and hypoxic-ischaemic injury were likely contributing factors, and the most common disposition for delirious patients was a skilled care facility (41/108, 38%). Among patients who were delirious during hospitalisation, 4/17 (24%) later screened positive for delirium at home based on caretaker assessment, 5/22 (23%) demonstrated signs of questionable cognitive impairment or cognitive impairment consistent with dementia and 3/25 (12%) screened positive for depression within 2 months after discharge.

CONCLUSION

Patients with COVID-19 commonly experience a prolonged course of delirium in the intensive care unit, likely with multiple contributing factors. Furthermore, neuropsychological impairment may persist after discharge.

Effects of perioperative interventions for preventing postoperative delirium: A protocol for systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Postoperative delirium (POD) not only increases the medical burden but also adversely affects patient prognosis. Although some cases of delirium can be avoided by early intervention, there is no clear evidence indicating whether any of these measures can effectively prevent POD in specific patient groups.

OBJECTIVE

The aim of this meta-analysis was to compare the efficacy and safety of the existing preventive measures for managing POD.

METHODS

The PubMed, OVID (Embase and MEDLINE), Web of Science, and the Cochrane Library databases were searched for articles published before January 2020. The relevant randomized controlled trials (RCTs) were selected based on the inclusion and exclusion criteria. Data extraction and methodological quality assessment were performed according to a predesigned data extraction form and scoring system, respectively. The interventions were compared on the basis of the primary outcome like incidence of POD, and secondary outcomes like duration of delirium and the length of intensive care unit and hospital stay.

RESULTS

Sixty-three RCTs were included in the study, covering interventions like surgery, anesthesia, analgesics, intraoperative blood glucose control, cholinesterase inhibitors, anticonvulsant drugs, antipsychotic drugs, sleep rhythmic regulation, and multi-modal nursing. The occurrence of POD was low in 4 trials that monitored the depth of anesthesia with bispectral index during the operation (P < .0001). Two studies showed that supplementary analgesia was useful for delirium prevention (P = .002). Seventeen studies showed that perioperative sedation with α2-adrenergic receptor agonists prevented POD (P = .0006). Six studies showed that both typical and atypical antipsychotic drugs can reduce the incidence of POD (P = .002). Multimodal nursing during the perioperative period effectively reduced POD in 6 studies (P < .00001). Furthermore, these preventive measures can reduce the duration of delirium, as well as the total and postoperative length of hospitalized stay for non-cardiac surgery patients. For patients undergoing cardiac surgery, effective prevention can only reduce the length of intensive care unit stay.

CONCLUSION

Measures including intraoperative monitoring of bispectral index, supplemental analgesia, α2-adrenergic receptor agonists, antipsychotic drugs, and multimodal care are helpful to prevent POD effectively. However, larger, high-quality RCTs are needed to verify these findings and develop more interventions and drugs for preventing postoperative delirium.

Comparative effectiveness of pharmacological interventions to prevent postoperative delirium: a network meta-analysis

Many pharmacologic agents were investigated for the effect to prevent delirium. We aimed to comprehensively compare the effect of the pharmacological interventions to prevent postoperative delirium. A Bayesian network meta-analysis of randomized trials was performed using random effects model. PubMed, the Cochrane Central Register of Controlled Trials, and Embase were searched on 20 January 2021. Randomized trials comparing the effect of a drug to prevent postoperative delirium with another drug or placebo in adult patients undergoing any kind of surgery were included. Primary outcome was the postoperative incidence of delirium. Eighty-six trials with 26,992 participants were included. Dexmedetomidine, haloperidol, and atypical antipsychotics significantly decreased the incidence of delirium than placebo [dexmedetomidine: odds ratio 0.51, 95% credible interval (CrI) 0.40-0.66, moderate quality of evidence (QOE); haloperidol: odds ratio 0.59, 95% CrI 0.37-0.95, moderate QOE; atypical antipsychotics: odds ratio 0.27, 95% CrI 0.14-0.51, moderate QOE]. Dexmedetomidine and atypical antipsychotics had the highest-ranking probabilities to be the best. However, significant heterogeneity regarding diagnostic time window as well as small study effects precludes firm conclusion.

Pharmacological strategies to prevent postoperative delirium: a systematic review and network meta-analysis

Background

Postoperative delirium (POD) is a condition of cerebral dysfunction and a common complication after surgery. This study aimed to compare and determine the relative efficacy of pharmacological interventions for preventing POD using a network meta-analysis.

Methods

We performed a systematic and comprehensive search to identify and analyze all randomized controlled trials until June 29, 2020, comparing two or more pharmacological interventions, including placebo, to prevent or reduce POD. The primary outcome was the incidence of POD. We performed a network meta-analysis and used the surface under the cumulative ranking curve (SUCRA) values and rankograms to present the hierarchy of the pharmacological interventions evaluated.

Results

According to the SUCRA value, the incidence of POD decreased in the following order: the combination of propofol and acetaminophen (86.1%), combination of ketamine and dexmedetomidine (86.0%), combination of diazepam, flunitrazepam, and pethidine (84.8%), and olanzapine (75.6%) after all types of anesthesia; combination of propofol and acetaminophen (85.9%), combination of ketamine and dexmedetomidine (83.2%), gabapentin (82.2%), and combination of diazepam, flunitrazepam, and pethidine (79.7%) after general anesthesia; and ketamine (87.1%), combination of propofol and acetaminophen (86.0%), and combination of dexmedetomidine and acetaminophen (66.3%) after cardiac surgery. However, only the dexmedetomidine group showed a lower incidence of POD than the control group after all types of anesthesia and after general anesthesia.

Conclusions

Dexmedetomidine reduced POD compared with the control group. The combination of propofol and acetaminophen and the combination of ketamine and dexmedetomidine seemed to be effective in preventing POD. However, further studies are needed to determine the optimal pharmacological intervention to prevent POD.

Diagnostic Value of Cholinesterase Activity for the Development of Postoperative Delirium after Cardiac Surgery

BACKGROUND

 Depression of cholinesterase (CHE) activity has been reported to lead to an amplified neuroinflammatory response, which clinically manifests as postoperative delirium (PD). This observational study investigates the association between CHE activity and the development of PD following elective cardiac surgery.

METHODS

 Patients with preexisting neurologic deficits or carotid artery disease as well as patients undergoing reoperations or procedures under circulatory arrest have been excluded from this study. The Mini-Mental State Examination, the Confusion Assessment Method for the Intensive Care Unit, and the Intensive Care Delirium Screening Checklist were performed at regular intervals. CHE activity was estimated pre- and postoperatively until postoperative day (POD) 5 and at discharge.

RESULTS

 A total of 107 patients were included. PD was diagnosed in 34 (31.8%) patients, who have been compared with those without PD. Time on ventilator, length of ICU, and hospital stay were longer in patients with PD (p = 0.001, p < 0.001, and p = 0.004, respectively). MMSE scores were lower in patients with PD (p < 0.001; p = 0.015). CHE activity on POD 1 to 4 as well as at discharge were lower in the delirium group (p = 0.041; p = 0.029; p = 0.015; p = 0.035; p = 0.028, respectively). A perioperative drop of CHE activity of more than 50% and a postoperative CHE activity below 4,800 U/L (on POD 0) were independently associated with an increased risk of development of PD (p = 0.038; p = 0.008, respectively).

CONCLUSION

 In addition to the established functional tests, routine estimation of CHE activity may serve as an additional diagnostic tool allowing for the timely diagnosis and treatment of PD in cardiac surgery patients.

AChE-activity in critically ill patients with suspected septic encephalopathy: a prospective, single-centre study

Background

Up to 70% of septic patients develop a diffuse brain dysfunction named “septic associated encephalopathy” which is often solely based on clinical impressions. However, the diagnosis of septic associated encephalopathy is outcome-relevant due to an increase in mortality in these patients. Neuroinflammation as well as a disturbance of cholinergic transmission are assumed to be the causes of both delirium and septic associated encephalopathy. An alteration in cholinergic activity can be objectified by measuring the erythrocytic acetylcholinesterase-activity. Single-point measurements of acetylcholinesterase-activity are of limited value because individual and dynamic changes over time have to be anticipated. Therefore, the hypothesis should be tested whether a longitudinal analysis of acetylcholinesterase-activity in critically ill patients can help to diagnose a suspected septic-associated encephalopathy and whether acetylcholinesterase-activity differs in comparison to non-septic patients.

Methods

In this prospective, observational, single-center study, 175 patients (45 with sepsis, 130 without sepsis) were included. All patients were admitted to the surgical Intensive Care Unit of the University hospital Ulm, Germany. Patients were examined daily for the presence of delirium using the CAM-ICU. Daily measurement of the acetylcholinesterase-activity was performed in all patients. The possible time-dependent change in acetylcholinesterase-activity was analyzed with a linear regression model considering repeated measurements. Using a time-adjusted model further factors able to affect AChE-activity were investigated. For nonparametric distributions quantitative data were compared using Wilcoxon matched-pairs test. For analysis of independent samples the Mann-Whitney test was performed.

Results

About 90% of septic patients with suspected septic associated encephalopathy exhibited a statistically significant time-dependent in- or decrease in acetylcholinesterase-activity over a period of at least 5 consecutive days.

Conclusion

Longitudinal measurement of acetylcholinesterase-activity over several consecutive days revealed a change from baseline only in septic patients with suspected septic-associated encephalopathy. Therefore, longitudinal measurement of acetylcholinesterase-activity is able to diagnose septic associated encephalopathy in septic patients with delirious symptoms.

Trial registration

Retrospectively registered at German Clinical Trials Register, registration number DRKS00020542, date of registration: January 27, 2020.

Current Evidence Regarding Biomarkers Used to Aid Postoperative Delirium Diagnosis in the Field of Cardiac Surgery-Review

Postoperative cognitive disorders after cardiac surgery may manifest as postoperative delirium (POD) or later as postoperative cognitive dysfunction (POCD). The incidence of POD after cardiac surgery ranges from 16% to 73%. In contrast to POD, POCD is usually diagnosed after the discharge from hospital, with an incidence of 30 to 70% of cases, very often noticed only by close relative or friends, decreasing after six (20–30%) and twelve (15–25%) months after surgery. Perioperative cognitive disorders are associated with adverse short- and long-term effects, including increased morbidity and mortality. Due to the complexity of delirium pathomechanisms and the difficulties in the diagnosis, researchers have not yet found a clear answer to the question of which patient will be at a higher risk of developing delirium. The risk for POD and POCD in older patients with numerous comorbidities like hypertension, diabetes, and previous ischemic stroke is relatively high, and the predisposing cognitive profile for both conditions is important. The aim of this narrative review was to identify and describe biomarkers used in the diagnosis of delirium after cardiac surgery by presenting a search through studies regarding this subject, which have been published during the last ten years. The authors discussed brain-derived biomarkers, inflammation-related biomarkers, neurotransmitter-based biomarkers, and others. Work based on inflammation-related biomarkers, which are characterized by the low cost of implementation and the effectiveness of delirium diagnosis, seems to be the closest to the goal of discovering an inexpensive and effective marker. Currently, the use of a panel of tests, and not a single biomarker, brings us closer to the discovery of a test, or rather a set of tests ideal for the diagnosis of delirium after cardiac surgery.

Sepsis-associated encephalopathy and septic encephalitis: an update

INTRODUCTION

Sepsis-associated encephalopathy (SAE) and septic encephalitis (SE) are associated with increased mortality, long-term cognitive impairment, and focal neurological deficits.

AREAS COVERED

The PUBMED database was searched 2016-2020. The clinical manifestation of SAE is delirium, SE additionally is characterized by focal neurological symptoms. SAE is caused by inflammation with endothelial/microglial activation, increase of permeability of the blood-brain-barrier, hypoxia, imbalance of neurotransmitters, glial activation, axonal, and neuronal loss. Septic-embolic (SEE) and septic-metastatic encephalitis (SME) are characterized by focal ischemia (SEE) and small abscesses (SME). The continuum between SAE, SME, and SEE is documented by imaging techniques and autopsies. The backbone of treatment is rapid optimum antibiotic therapy. Experimental approaches focus on modulation of inflammation, stabilization of the blood-brain barrier, and restoration of membrane/mitochondrial function.

EXPERT OPINION

The most promising diagnostic approaches are new imaging techniques. The most important measure to fight delirium remains establishment of daily structure and adequate sensory stimuli. Dexmedetomidine and melatonin appear to reduce the frequency of delirium, their efficacy in SAE and SE remains to be established. Drugs already licensed for other indications or available as food supplements which may be effective in SAE are statins, L-DOPA/benserazide, β-hydroxybutyrate, palmitoylethanolamide, and tetracyclines or other bactericidal non-lytic antibiotics.

Antipsychotic Drugs in Prevention of Postoperative Delirium-What Is Known in 2020?

Delirium is one of the most frequently reported neuropsychiatric complications in the perioperative period, especially in the population of elderly patients who often suffer from numerous comorbidities undergoing extensive or urgent surgery. It can affect up to 80% of patients who require hospitalization in an intensive care setting postoperatively. Delirium increases mortality, morbidity, length of hospital stay, and cost of treatment. An episode of delirium in the acute phase may lower the general quality of life and increases the risk of cognitive decline long-term. Since pharmacological treatment of delirium is not highly effective, focus of research has shifted towards developing preventive strategies. We aimed to perform a review of the topic based on the most recent literature. We conclude that, based on the available data, it seems impossible to make strong recommendations for using antipsychotic drugs in prophylaxis. Further research should answer the question what, if any, benefit patients receive from the pharmacological prevention of delirium, and which agents should be used.

Multi-disciplinary and pharmacological interventions to reduce post-operative delirium in elderly patients: A systematic review and meta-analysis

STUDY OBJECTIVE

An estimated 80% of older people undergoing surgery develop postoperative delirium (POD) making them a high-risk group. Research in this area is growing fast but there is no established consensus on strategies for POD prevention or management. A systematic review and meta-analysis were conducted to synthesise data on clinical interventions used to reduce POD among older people undergoing elective and emergency surgery.

METHODS

A range of database searches generated 336 papers. A total of 25 studies met the inclusion criteria and were assessed using the Joanna Briggs Institute Critical Appraisal Checklist. The studies were undertaken across the world.

RESULTS

This review identified a range of intervention approaches: comparisons between anaesthetic and sedatives agents, medication-specific interventions and multidisciplinary models of care. Results found more consistencies across multidisciplinary interventions than the pharmacological interventions. In pooled analyses, haloperidol (OR 0.74; 95% CI (confidence interval) 0.44, 1.26) was not statistically significantly associated with reduced POD incidence any more than a placebo.

CONCLUSION

There is a need to implement multidisciplinary interventions, as well as collaboration between clinicians on pre- and postoperative care practices regarding pharmacological interventions to more effectively reduce and manage POD in older people.

American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on Postoperative Delirium Prevention

Postoperative delirium is a geriatric syndrome that manifests as changes in cognition, attention, and levels of consciousness after surgery. It occurs in up to 50% of patients after major surgery and is associated with adverse outcomes, including increased hospital length of stay, higher cost of care, higher rates of institutionalization after discharge, and higher rates of readmission. Furthermore, it is associated with functional decline and cognitive impairments after surgery. As the age and medical complexity of our surgical population increases, practitioners need the skills to identify and prevent delirium in this high-risk population. Because delirium is a common and consequential postoperative complication, there has been an abundance of recent research focused on delirium, conducted by clinicians from a variety of specialties. There have also been several reviews and recommendation statements; however, these have not been based on robust evidence. The Sixth Perioperative Quality Initiative (POQI-6) consensus conference brought together a team of multidisciplinary experts to formally survey and evaluate the literature on postoperative delirium prevention and provide evidence-based recommendations using an iterative Delphi process and Grading of Recommendations Assessment, Development and Evaluation (GRADE) Criteria for evaluating biomedical literature.

Emergency Surgery and Male Gender Are Risk Factors of Postoperative Delirium After General or Gastrointestinal Surgery in Elderly Patients: A Multicenter Cohort Study

Objective

The aim of this study was to investigate the incidence and risk factors of postoperative delirium (PD) in elderly patients after general or gastrointestinal surgery.

Summary of background data

Societies worldwide are rapidly aging, and the number of surgeries in elderly patients has been increasing. PD, which adversely influences postoperative course, has thus become more common.

Methods

The Surgery and Anesthesia Network Group of the National Hospital Organization in Japan conducted this retrospective cohort study of patients older than 70 years of age who underwent general or gastrointestinal surgery.

Results

A total of 219 patients from 9 participating institutes underwent surgery between July 2013 and August 2014. We excluded 2 patients who died within 2 weeks after surgery. Of the remaining 217 cases, 31 (14.3%) developed PD. These patients were older (80 versus 76 years, P = 0.013), more likely to be male (74.2 versus 54.8%, P = 0.039), and had higher American Society of Anesthesia Physical Status scores than those without PD. Emergency surgery was more common than elective surgery in the PD group (41.9 versus 10.2%, P &lt; 0.0001). Multivariate analysis showed that male gender (odds ratio, 3.31; 95% confidence interval, 1.32 to 9.39; P = 0.0098) and emergency surgery (odds ratio, 7.47; 95% confidence interval, 2.79 to 20.83; P &lt; 0.0001) were independent risk factors of PD.

Conclusions

The incidence of PD was high in male patients and those undergoing emergency surgery. Effective interventions in these groups will be necessary to improve treatment outcomes in elderly patients.

The pharmacotherapeutic management of postoperative delirium: an expert update

INTRODUCTION

Postoperative delirium is a common sequela in older adults in the peri-operative period leading to poor outcomes with a complex pathophysiology which has led to a variety of different pharmacologic agents employed in attempts to prevent and treat this syndrome. No pharmacologic agent has been approved to treat this disorder, but this review discusses the pharmacologic strategies which have been tried based on the hypotheses of the causation of the syndrome including neurotransmitter imbalance, inflammation, and oxidative stress.

AREAS COVERED

Systematic reviews and meta-analyses of randomized clinical trials (RCTs) were included via search of electronic databases specifically for the terms postoperative delirium and pharmacologic treatments. With this approach, the recurrent topics of analgesia and sedation, antipsychotics, acetylcholinesterase inhibitors (AchE-Is), inflammation, and melatonin were emphasized and provided the outline for this review.

EXPERT OPINION

Research evidence does not support any particular agent in any of the pharmacologic classes reviewed. However, there is some potential benefit with dexmedetomidine, melatonin, and the monitoring of anesthetic agents all of which need further clinical trials to validate these conclusions. Exploration of ways to improve studies and the application of novel pharmacologic agents may offer future benefit.

Results from a double blinded, randomised, placebo-controlled, feasibility trial of melatonin for the treatment of delirium in older medical inpatients

BACKGROUND

Delirium is common in elderly inpatients, causing distress, cognitive decline and death. No known intervention improves the course of delirium; current treatments are symptomatic, and limited by lack of efficacy and adverse effects. There is an urgent need to find an effective treatment for delirium.

AIMS

To determine the feasibility of a trial of oral melatonin 5 mg nightly for five nights for the treatment of delirium in older medical inpatients, and determine the participants required to demonstrate a clinically and statistically significant decrease in severity of delirium in older medical inpatients treated with melatonin.

METHODS

This was a double blinded, randomised controlled trial in general internal medicine units of a tertiary teaching hospital. Older (≥70 years) inpatients with confusion assessment method positive hyperactive or mixed delirium were suitable for inclusion. Subjects received melatonin 5 mg oral nightly for five nights or matching placebo. The primary outcome was the Memorial Delirium Assessment Scale (MDAS) administered daily.

RESULTS

No adverse effects occurred due to melatonin. In the treatment group, the mean change in MDAS from baseline during treatment period was 2.5 ± 5.0 points, in the placebo group, 2.1 ± 4.1 points, a non-significant difference. A power calculation accounting for drop-out (31.0%), suggests 120 participants would be required to demonstrate with 90% power that melatonin 5 mg reduces the severity of delirium by 3 points or more on MDAS.

CONCLUSIONS

A trial of the hypothesis that 5 mg melatonin nightly for five nights reduces delirium severity in older medical inpatients would require 120 patients, and is feasible.

Cholinesterase alterations in delirium after cardiosurgery: a German monocentric prospective study

OBJECTIVES

Postoperative delirium (POD) is a common complication after elective cardiac surgery. Recent evidence indicates that a disruption in the normal activity of the cholinergic system may be associated with delirium.

DESIGN

Prospective observational study.

SETTING

Single-centre at a European academic hospital.

PRIMARY AND SECONDARY OUTCOME MEASURES

In our study the enzyme activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were determined preoperatively as well as on the first and second postoperative day. The confusion assessment method for the intensive care unit was used to screen patients for the presence of POD.

RESULTS

A total of 114 patients were included in the study. POD was associated with a decrease in BChE activity on postoperative day 1 (p=0.03). In addition, patients who developed POD, had significantly lower preoperative AChE activity than patients without POD (p<0.01). Multivariate analysis identified a preoperatively decreased AChE activity (OR 3.1; 95% CI 1.14 to 8.46), anticholinergic treatment (OR 5.09; 95% CI 1.51 to 17.23), elevated European System for Cardiac Operative Risk Evaluation (OR 3.68; 95% CI 1.04 to 12.99) and age (OR 3.02; 95% CI 1.06 to 8.62) to be independently associated with the development of POD.

CONCLUSIONS

We conclude that a reduction in the acetylcholine hydrolysing enzyme activity in patients undergoing cardiac surgery may correlate with the development of POD.

Efficacy of Low-Dose Prophylactic Quetiapine on Delirium Prevention in Critically Ill Patients: A Prospective, Randomized, Double-Blind, Placebo-Controlled Study

Purpose: To evaluate the efficacy of short-term low-dose quetiapine for delirium prevention in critically ill patients. Methods: In this prospective, a single-center, randomized, double-blind, placebo-controlled trial, adult patients who were admitted from July 2015 to July 2017 to a medical intensive care unit (ICU) of a tertiary teaching hospital affiliated to Seoul National University were included. Quetiapine (12.5 mg or 25 mg oral at night; N = 16) or placebo (N = 21) was administered according to randomization until ICU discharge or the 10th ICU day. The primary endpoint was the incidence of delirium within the first 10 ICU days. Secondary endpoints included the rate of positive Confusion Assessment Method for the ICU (CAM-ICU) (the number of positive CAM-ICU counts/the number of total CAM-ICU counts), delirium duration, successful extubation, and overall mortality. Result: The incidence of delirium during the 10 days after ICU admission was 46.7% (7/15) in the quetiapine group and 55.0% (11/20) in the placebo group (p = 0.442). In the quetiapine group, the rate of positive CAM-ICU was significantly lower than in the placebo group (14.4% vs. 37.4%, p = 0.048), delirium duration during the study period was significantly shorter (0.28 day vs. 1.83 days, p = 0.018), and more patients in the quetiapine than in the placebo group were weaned from mechanical ventilation successfully (84.6% vs. 47.1%, p = 0.040). Conclusions: Our study suggests that prophylactic use of low-dose quetiapine could be helpful for preventing delirium in critically ill patients. A further large-scale prospective study is needed.

Impact of a Premorbid Psychiatric Disorder on the Incidence of Delirium during ICU Stay, Morbidity, and Long-Term Mortality

Introduction

Delirium during ICU stay is a widespread problem with complex aetiology. A premorbid psychiatric disorder has been associated with an increased incidence of delirium in the general hospital population, but data on the impact of ICU delirium and consequences for morbidity and long-term mortality remain scarce.

Methods

In this single-centre retrospective analysis, 472 patients with an ICU stay >48 hours were included during a 2-year period. Postresuscitation and neurosurgical patients were not included. The primary aim of the study was to establish the incidence and duration of delirium during ICU stay in patients with (PS group) and without (NPS group) a premorbid psychiatric disorder. Data were analysed with applicable nonparametric tests. In a secondary analysis, patients were compared according to the presence or absence of delirium. Finally, a binary logistic regression model was constructed to correct for potential confounders.

Results

Of all patients, 19.7% were included in the PS group. Baseline characteristics with respect to severity of illness and type of admission did not differ between groups, but PS patients were significantly younger and more often female in comparison with NPS patients. The overall incidence of delirium during ICU was 57% and did not significantly differ between groups (65% in PS group vs. 56% in the NPS group, p=0.13). In a univariate analysis, the presence of a psychiatric history was also associated with prolonged mechanical ventilation, length of stay ICU, and hospital stay, but not with long-term all-cause mortality. The presence of delirium at any time during ICU admission was significantly associated with prolonged mechanical ventilation and prolonged ICU and hospital stay, but not with mortality. In a Kaplan–Meier analysis, 5-year all-cause mortality was clearly separated between groups, but the difference remained statistically insignificant (X²=3.01, p=0.08). In a binary logistic regression model, age, male sex, APACHE III score, and premorbid psychiatric disorder (OR 1.8, CI 1.1–3.0; p=0.023) were all independently associated with the presence of delirium.

Conclusions

In ICU patients with a length of stay >48 hours and a premorbid psychiatric disorder, the incidence of delirium was not significantly higher in comparison with patients without a premorbid psychiatric disorder.

Special Considerations for the Aging Brain and Perioperative Neurocognitive Dysfunction

Postoperative delirium and postoperative cognitive dysfunction (POCD) occur commonly in older adults after surgery and are frequently underrecognized. Delirium has been associated with worse outcomes, and both delirium and cognitive dysfunction increase the risk of long-term cognitive decline. Although the pathophysiology of delirium and POCD have not been clearly defined, risk factors for both include increasing age, lower levels of education, and baseline cognitive impairment. In addition, developing delirium increases the risk of POCD. This article examines interventions that may reduce the risk of developing delirium and POCD and improve long-term recovery and outcomes in the vulnerable older population.

Pharmacological Prevention of Postoperative Delirium: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

The high prevalence of delirium among postoperative patients has increased morbidity and mortality. The kind of drug that can effectively reduce the incidence of delirium has become the focus of discussion in recent years. However, a consensus in this respect has yet to be reached.

Methods

Randomized controlled trials (RCTs) were retrieved from the PubMed, Cochrane Library, ClinicalTrials.gov, and Embase databases from their inception through October 12, 2018. We included RCTs of pharmacological prevention for postoperative delirium in adults (at least 18 years), and the Cochrane risk of bias tool was used to evaluate the methodological quality of trials. The primary outcomes were the risk ratios (RRs) of incidence of postoperative delirium, and the secondary outcomes were the RRs of mortality and adverse events in the intervention and control groups.

Results

Thirty-eight trials, which comprised 20302 patients and 18 different drugs, were included in the analysis. Of the 38 studies, 17 were rated as low risk with respect to methodological quality. Dexmedetomidine administration (RR 0.58, 95%CI 0.44-0.76, P<0.01) was associated with a significantly lower incidence of postoperative delirium than the control conditions. However, the findings from the studies with a low risk of bias did not show a significant difference in this beneficial effect (RR 0.64, 95%CI 0.39-1.04, P=0.07). The antipsychotic drugs olanzapine (RR 0.44, 95%CI 0.30- 0.65, P<0.01) and risperidone (RR 0.42, 95%CI 0.19-0.92, P=0.03) had promising effects, but there was a lack of sufficient evidence to obtain a definitive conclusion. The beneficial effect of other drugs, including haloperidol, methylprednisolone, dexamethasone, gabapentin, ketamine, cyproheptadine, donepezil, hypertonic saline, melatonin, nimodipine, ondansetron, pregabalin, rivastigmine, TJ-54, and tryptophan, was not proven on the basis of present evidence.

Conclusion

Among the pharmacological prophylactic measures for postoperative delirium, dexmedetomidine, olanzapine, and risperidone showed higher efficacy than other drugs. However, more high-quality evidence is needed to confirm these results.

Postoperative delirium in the elderly: the potential neuropathogenesis

Postoperative delirium (POD) is a neurobehavioral syndrome caused by dysfunction of neural activity mainly in elderly people. POD is not uncommon, but under-recognized, and often serious. Multifactorial causes including aging, acetylcholine deficiency, sleep deprivation and intraoperative hypoxia have been proposed attempting to explain the processes leading to the development of POD. To date, however, no specific pathophysiologic mechanism has been identified. Here, we summarize the five most prominent theories (neuronal aging, neuroinflammation, neurotransmitter imbalance, neuroendocrine activation, and network connectivity change) to explain the development of delirium. Understanding of the neuropathogenesis of delirium will help focus future research, and assist in developing prophylactic and treatment strategies.

Neurocognitive Function after Cardiac Surgery: From Phenotypes to Mechanisms

For half a century, it has been known that some patients experience neurocognitive dysfunction after cardiac surgery; however, defining its incidence, course, and causes remains challenging and controversial. Various terms have been used to describe neurocognitive dysfunction at different times after cardiac surgery, ranging from "postoperative delirium" to "postoperative cognitive dysfunction or decline." Delirium is a clinical diagnosis included in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). Postoperative cognitive dysfunction is not included in the DSM-5 and has been heterogeneously defined, though a recent international nomenclature effort has proposed standardized definitions for it. Here, the authors discuss pathophysiologic mechanisms that may underlie these complications, review the literature on methods to prevent them, and discuss novel approaches to understand their etiology that may lead to novel treatment strategies. Future studies should measure both delirium and postoperative cognitive dysfunction to help clarify the relationship between these important postoperative complications.

Pharmacologic prevention of postoperative delirium after on-pump cardiac surgery: A meta-analysis of randomized trials

BACKGROUND

Postoperative delirium is a prevalent and disabling mental disorder in patients undergoing on-pump cardiac surgery. There is some evidence that the use of pharmacological interventions may reduce the risk of developing of postoperative delirium. Therefore, the aim of this meta-analysis was to determine the effect of pharmacologic agents for the prevention postoperative delirium after cardiac surgery.

METHODS

Randomized controlled trials (RCTs) were identified through a systematic literature search of electronic databases and article references up to October 2016. End points included incidence of postoperative delirium, severity of postoperative delirium, cognitive disturbances of postoperative delirium, duration of postoperative delirium, length of stay in intensive care unit (ICU) and hospital, and short-term mortality.

RESULTS

A total of 14 RCTs with an aggregate of 14,139 patients were included. The results of the present meta-analysis show that pharmacologic agents significantly decrease postoperative delirium [relative risk (RR), 0.83; 95% confidence interval (95% CI), 0.75-0.91, P < .00001] and duration of postoperative delirium (RR = -0.37, 95% CI = -0.47 to -0.27, P < .00001) after on-pump cardiac surgery. In addition, subgroup analysis shows that dexamethasone and dexamethasone were associated with a trend toward a reduction in postoperative delirium (RR, 0.45; 95% CI, 0.30-0.66, P < .0001; RR, 0.80; 95% CI, 0.68-0.93, P = .003, respectively). However, our results fail to support the assumption that pharmacologic prophylaxis is associated with a positively reduction in short-term mortality, length of ICU, or hospital stay.

CONCLUSION

This meta-analysis suggests that the perioperative use of pharmacologic agents can prevent postoperative delirium development in patients undergoing cardiac surgery. However, there remain important gaps in the evidence base on a few small studies with multiple limitations. Further large-scale, high-quality RCTs are needed in this area.

The Impact of a Long-Term Rivastigmine and Donepezil Treatment on All-Cause Mortality in Patients With Alzheimer's Disease

Cholinesterase inhibitors (ChEIs) are the mainstays of symptomatic treatment of Alzheimer's disease (AD); however, their efficacy is limited, and their use was associated with deaths in some groups of patients. The aim of the current study was to assess the impact of the long-term use of ChEIs on mortality in patients with AD. This observational, longitudinal study included 1171 adult patients with a diagnosis of AD treated with donepezil or rivastigmine. Each patient was observed for 24 months or until death. The cognitive and functional assessments, the use of ChEIs, memantine, antipsychotics, antidepressants, and anxiolytics were recorded. The total number of deaths at the end of the observational period was 99 (8.45%). The patients who had received rivastigmine treatment were at an increased risk of death in the follow-up period. The higher risk of death in the rivastigmine group remained significant in multivariate Cox regression models.

Perioperative cognitive protection

There is significant evidence that many older surgical patients experience at least a transient decrease in cognitive function. Although there is still equipoise regarding the degree, duration, and mechanism of cognitive dysfunction, there is a concurrent need to provide best-practice clinical evidence. The two major cognitive disorders seen after surgery are postoperative delirium and postoperative cognitive dysfunction. Delirium is a public health problem; millions of dollars are spent annually on delirium-related medical resource use and prolonged hospital stays. Postoperative cognitive dysfunction is a research construct that historically signifies decline in performance on a neuropsychiatric test or group of tests and begins days to weeks after surgery. This review focuses on the current state of information gathered by several interdisciplinary stakeholder groups. Although there is still a need for high-level evidence to guide clinical practice, there is an emerging literature that can guide practitioners.

Acetylcholinesterase Activity Measurement and Clinical Features of Delirium

AIMS

Cholinergic deficiency is commonly implicated in the pathophysiology of delirium. We aimed to investigate the relationship between directly measured serum acetylcholinesterase (AChE) activity and (1) clinical features of delirium and (2) outcomes among older hospital patients with delirium.

METHODS

Hospitalised patients with delirium were recruited, and delirium motor subtype, severity and duration of delirium were measured. Serum AChE activity was measured using a colorimetric assay.

RESULTS

The mean AChE activity for the whole sample was 2.46 μmol/μL/min (standard deviation 1.75). Higher AChE activity was associated with increased likelihood of hypoactive delirium rather than the hyperactive or mixed subtype (odds ratio 1.98, 95% confidence interval 1.10-3.59).

CONCLUSION

Higher AChE activity was associated with hypoactive delirium but did not predict outcomes. Simple enhancement of cholinergic neurotransmission may not be sufficient to treat delirium.

Anesthetic Immunomodulation of the Neuroinflammation in Postoperative Cognitive Dysfunction

Postoperative delirium and cognitive dysfunction are phenomena that are associated with increases in morbidity, mortality, and resource utilization after surgery. This review scrutinized a number of studies in order to better characterize the biochemical basis for associated cognitive dysfunction and delirium, with particular focus paid to the interactions of the cholinergic system with innate immunity and how the modulation of the immune system contributes to associated neuroinflammation. Despite the clinical impact of postoperative cognitive dysfunction, evidence-based protocols for the prevention and treatment of these disorders are still lacking. Several previous trials have attempted to prevent or treat clinical manifestation by modulation of the cholinergic system with acetylcholinesterase inhibitors, the results of which have been largely ambiguous at best. As the biochemical basis of postoperative cognitive dysfunction becomes more clearly defined, future research into therapeutics based on immune modulation and treatment of neuroinflammation may prove to be very promising.

Delirium after cardiac surgery. Incidence, phenotypes, predisposing and precipitating risk factors, and effects

BACKGROUND

In cardiac surgical patients little is known about different phenotypes of delirium and how the symptoms fluctuate over time.

OBJECTIVES

Evaluate risk factors, incidence, fluctuations, phenotypic characteristics and impact on patients' outcomes of delirium.

METHODS

Prospective longitudinal study. In postoperative intensive care unit 199 patient were assessed three-times a day through an adapted versions of the Intensive Care Delirium Screening Checklist.

RESULTS

Delirium and subsyndromal delirium incidence were 30.7% and 31.2%, respectively. Delirium manifested mostly in the hypoactive form and showed a fluctuating trend for several days. Atrial fibrillation, benzodiazepine/opioids dosages, hearing impairment, extracorporeal circulation length, SAPS-II and mean arterial pressure were independent predictors for delirium. Delirium was a statistically significant predictor of chemical/physical restraint use and hospital length of stay.

CONCLUSIONS

Given the fluctuating and phenotypic characteristics, delirium screening should be a systematic/intentional activity. Multidisciplinary prevention strategies should be implemented to identify and treat the modifiable risk factors.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

BACKGROUND AND PURPOSE

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 and published in the Journal of JSICM, [2017; Volume 24 (supplement 2)] 10.3918/jsicm.24S0001 and Journal of Japanese Association for Acute Medicine [2017; Volume 28, (supplement 1)] http://onlinelibrary.wiley.com/doi/10.1002/jja2.2017.28.issue-S1/issuetoc.This abridged English edition of the J-SSCG 2016 was produced with permission from the Japanese Association of Acute Medicine and the Japanese Society for Intensive Care Medicine.

METHODS

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ) and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (> 66.6%) majority vote of each of the 19 committee members.

RESULTS

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation, and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty-seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for five CQs.

CONCLUSIONS

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016)

Background and Purpose

The Japanese Clinical Practice Guidelines for Management of Sepsis and Septic Shock 2016 (J-SSCG 2016), a Japanese-specific set of clinical practice guidelines for sepsis and septic shock created jointly by the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine, was first released in February 2017 in Japanese. An English-language version of these guidelines was created based on the contents of the original Japanese-language version.

Methods

Members of the Japanese Society of Intensive Care Medicine and the Japanese Association for Acute Medicine were selected and organized into 19 committee members and 52 working group members. The guidelines were prepared in accordance with the Medical Information Network Distribution Service (Minds) creation procedures. The Academic Guidelines Promotion Team was organized to oversee and provide academic support to the respective activities allocated to each Guideline Creation Team. To improve quality assurance and workflow transparency, a mutual peer review system was established, and discussions within each team were open to the public. Public comments were collected once after the initial formulation of a clinical question (CQ), and twice during the review of the final draft. Recommendations were determined to have been adopted after obtaining support from a two-thirds (>66.6%) majority vote of each of the 19 committee members.

Results

A total of 87 CQs were selected among 19 clinical areas, including pediatric topics and several other important areas not covered in the first edition of the Japanese guidelines (J-SSCG 2012). The approval rate obtained through committee voting, in addition to ratings of the strengths of the recommendation and its supporting evidence were also added to each recommendation statement. We conducted meta-analyses for 29 CQs. Thirty seven CQs contained recommendations in the form of an expert consensus due to insufficient evidence. No recommendations were provided for 5 CQs.

Conclusions

Based on the evidence gathered, we were able to formulate Japanese-specific clinical practice guidelines that are tailored to the Japanese context in a highly transparent manner. These guidelines can easily be used not only by specialists, but also by non-specialists, general clinicians, nurses, pharmacists, clinical engineers, and other healthcare professionals.