Associations of environmental and lifestyle factors with spatial navigation in younger and older adults.

Objective: Advanced age is associated with prominent impairment in allocentric navigation dependent on the hippocampus. This study examined whether age-related impairment in allocentric navigation and strategy selection was associated with sleep disruption or circadian rest-activity fragmentation. Further, we examined whether associations with navigation were moderated by perceived stress and physical activity.

Quiescence during burst suppression and postictal generalized EEG suppression are distinct patterns of activity.

Objective: Periods of low-amplitude electroencephalographic (EEG) signal (quiescence) are present during both anesthetic-induced burst suppression (BS) and postictal generalized electroencephalographic suppression (PGES). PGES following generalized seizures induced by electroconvulsive therapy (ECT) has been previously linked to antidepressant response. The commonality of quiescence during both BS and PGES motivated trials to recapitulate the antidepressant effects of ECT using high doses of anesthetics.

Evaluation of the 3-Minute Diagnostic Confusion Assessment Method for Identification of Postoperative Delirium in Older Patients.

Importance: Delirium is a common postoperative complication in older patients that often goes undetected and might lead to worse outcomes. The 3-Minute Diagnostic Confusion Assessment Method (3D-CAM) might be a practical tool for routine clinical diagnosis of delirium.

Objective: To assess the 3D-CAM for detecting postoperative delirium compared with the long-form CAM used for research purposes.

Effect of electroencephalogram-guided anaesthesia administration on 1-yr mortality: follow-up of a randomised clinical trial.

Background: Intraoperative EEG suppression duration has been associated with postoperative delirium and mortality. In a clinical trial testing anaesthesia titration to avoid EEG suppression, the intervention did not decrease the incidence of postoperative delirium, but was associated with reduced 30-day mortality. The present study evaluated whether the EEG-guided anaesthesia intervention was also associated with reduced 1-yr mortality.

Recovery of consciousness and cognition after general anesthesia in humans.

Understanding how the brain recovers from unconsciousness can inform neurobiological theories of consciousness and guide clinical investigation. To address this question, we conducted a multicenter study of 60 healthy humans, half of whom received general anesthesia for 3 hr and half of whom served as awake controls. We administered a battery of neurocognitive tests and recorded electroencephalography to assess cortical dynamics.

Preoperative Cognitive Abnormality, Intraoperative Electroencephalogram Suppression, and Postoperative Delirium: A Mediation Analysis.

Background: Postoperative delirium is a common complication that hinders recovery after surgery. Intraoperative electroencephalogram suppression has been linked to postoperative delirium, but it is unknown if this relationship is causal or if electroencephalogram suppression is merely a marker of underlying cognitive abnormalities. The hypothesis of this study was that intraoperative electroencephalogram suppression mediates a nonzero portion of the effect between preoperative abnormal cognition and postoperative delirium.

Duration of EEG suppression does not predict recovery time or degree of cognitive impairment after general anaesthesia in human volunteers.

Background: Burst suppression occurs in the EEG during coma and under general anaesthesia. It has been assumed that burst suppression represents a deeper state of anaesthesia from which it is more difficult to recover. This has not been directly demonstrated, however.

Perioperative Epidural Use and Risk of Delirium in Surgical Patients: A Secondary Analysis of the PODCAST Trial.

Background: Postoperative delirium is an important public health concern without effective prevention strategies. This study tested the hypothesis that perioperative epidural use would be associated with decreased risk of delirium through postoperative day 3.

Methods: This was a secondary, observational, nonrandomized analysis of data from The Prevention of Delirium and Complications Associated With Surgical Treatments Trial (PODCAST; NCT01690988).

Effect of Electroencephalography-Guided Anesthetic Administration on Postoperative Delirium Among Older Adults Undergoing Major Surgery: The ENGAGES Randomized Clinical Trial.

Importance: Intraoperative electroencephalogram (EEG) waveform suppression, often suggesting excessive general anesthesia, has been associated with postoperative delirium.

Objective: To assess whether EEG-guided anesthetic administration decreases the incidence of postoperative delirium.

Design, Setting, And Participants: Randomized clinical trial of 1232 adults aged 60 years and older undergoing major surgery and receiving general anesthesia at Barnes-Jewish Hospital in St Louis.

Early Postoperative Actigraphy Poorly Predicts Hypoactive Delirium.

Study Objectives: Delirium is a postoperative complication accompanied by disturbances in attention, cognition, arousal, and psychomotor activity. Wrist actigraphy has been advocated to study inactivity and inferred sleep patterns during delirium. We hypothesized that altered patterns of motor activity or immobility, reflective of disordered sleep and wakefulness patterns, would serve as predictive markers of hypoactive postoperative delirium.

Reliability and accuracy of delirium assessments among investigators at multiple international centres.

Introduction: Delirium is a common, serious postoperative complication. For clinical studies to generate valid findings, delirium assessments must be standardised and administered accurately by independent researchers. The Confusion Assessment Method (CAM) is a widely used delirium assessment tool.

Intraoperative ketamine for prevention of depressive symptoms after major surgery in older adults: an international, multicentre, double-blind, randomised clinical trial.

Background: Ketamine is a general anaesthetic with anti-depressant effects at subanaesthetic doses. We hypothesised that intraoperative administration of ketamine would prevent or mitigate postoperative depressive symptoms in surgical patients.

Methods: We conducted an international, randomised clinical trial testing the effects of intraoperative administration of ketamine [0.

Intraoperative electroencephalogram suppression at lower volatile anaesthetic concentrations predicts postoperative delirium occurring in the intensive care unit.

Background: Postoperative delirium is a common complication associated with increased morbidity and mortality. A recently-reported association between intraoperative electroencephalogram suppression and postoperative delirium might be mediated in some patients by a heightened sensitivity to volatile anaesthetics.

Methods: This retrospective cohort study included 618 elective surgery patients with planned intensive care unit admission, who also received intraoperative electroencephalogram monitoring and had delirium assessments documented in the medical record.

Cognitive and Neurophysiological Recovery Following Electroconvulsive Therapy: A Study Protocol.

Electroconvulsive therapy (ECT) employs the elective induction of generalizes seizures as a potent treatment for severe psychiatric illness. As such, ECT provides an opportunity to rigorously study the recovery of consciousness, reconstitution of cognition, and electroencephalographic (EEG) activity following seizures. Fifteen patients with major depressive disorder refractory to pharmacologic therapy will be enrolled (Clinicaltrials.

Ability of postoperative delirium to predict intermediate-term postoperative cognitive function in patients undergoing elective surgery at an academic medical centre: protocol for a prospective cohort study.

Introduction: Postoperative delirium (POD) is a common complication in elderly patients, characterised by a fluctuating course of altered consciousness, disordered thinking and inattention. Preliminary research has linked POD with persistent cognitive impairment and decreased quality of life. However, these findings maybe confounded by patient comorbidities, postoperative complications and frailty.

Achieving Milestones as a Prerequisite for Proceeding With a Clinical Trial.

Background: Although the National Institutes of Health (NIH) invests $30 billion in research annually, many funded studies fail to generate results that can inform practice. The National Institutes of Health introduced a phased funding mechanism as one potential solution. Study-specific milestones are established for an initial pilot phase.

Intraoperative ketamine for prevention of postoperative delirium or pain after major surgery in older adults: an international, multicentre, double-blind, randomised clinical trial.

Background: Delirium is a common and serious postoperative complication. Subanaesthetic ketamine is often administered intraoperatively for postoperative analgesia, and some evidence suggests that ketamine prevents delirium. The primary purpose of this trial was to assess the effectiveness of ketamine for prevention of postoperative delirium in older adults.

Protocol for the Electroencephalography Guidance of Anesthesia to Alleviate Geriatric Syndromes (ENGAGES) study: a pragmatic, randomised clinical trial.

Introduction: Postoperative delirium, arbitrarily defined as occurring within 5 days of surgery, affects up to 50% of patients older than 60 after a major operation. This geriatric syndrome is associated with longer intensive care unit and hospital stay, readmission, persistent cognitive deterioration and mortality. No effective preventive methods have been identified, but preliminary evidence suggests that EEG monitoring during general anaesthesia, by facilitating reduced anaesthetic exposure and EEG suppression, might decrease incident postoperative delirium.

Intraoperative Electroencephalogram Suppression Predicts Postoperative Delirium.

Background: Postoperative delirium is a common complication associated with increased morbidity and mortality, longer hospital stays, and greater health care expenditures. Intraoperative electroencephalogram (EEG) slowing has been associated previously with postoperative delirium, but the relationship between intraoperative EEG suppression and postoperative delirium has not been investigated.

Methods: In this observational cohort study, 727 adult patients who received general anesthesia with planned intensive care unit admission were included.

The Prevention of Delirium and Complications Associated with Surgical Treatments (PODCAST) study: protocol for an international multicentre randomised controlled trial.

Introduction: Postoperative delirium is one of the most common complications of major surgery, affecting 10-70% of surgical patients 60 years and older. Delirium is an acute change in cognition that manifests as poor attention and illogical thinking and is associated with longer intensive care unit (ICU) and hospital stay, long-lasting cognitive deterioration and increased mortality. Ketamine has been used as an anaesthetic drug for over 50 years and has an established safety record.