The hypothesis is that the EEG-guided anesthetic protocol will improve postoperative quality of life. Patient self-reported Health-related Quality of Life information will be assessed through the Veteran's RAND 12-item Health Survey at baseline and during follow-up (30-day and 1-year).

As measured by the FAM-CAM and patient perceptions

Delirium incidence, duration and severity have all been shown to be associated with other (downstream) clinically relevant outcomes, including mortality, length of ICU stay, length of hospital stay, falls, cognitive decline and functional decline.

Given that postoperative delirium is common and may relate to uncontrolled pain, this has important implications for the assessment and treatment of postoperative pain. We plan to compare patient reported and behavioral pain assessments in both non-delirious and delirious patients.

Postoperative disturbances in sleep abnormalities have previously been associated with postoperative delirium. Measures of root mean-squared activity (RMSactivity) was calculated by combining counts (binned in 1-minute intervals) across all three accelerometer axes (X, Y, and Z) from 16:00 on the day of surgery to 6:00 the following day. Median activity count was calculated from all minutes with nonzero RMS activity within each epoch- higher values indicate more movement.

Routine clinical (i.e. conducted by ICU nursing staff) delirium assessments in the intensive care units (conducted with the CAM-ICU) will be collected when these are available. Comparison will be made on the outcome of the assessment (positive for delirium or negative by delirium) between these routine clinical assessments and the assessments made by the research team. Since the purpose of this is to determine whether clinical staff are picking up episodes of delirium compared to researcher's assessment in all patients regardless of treatment group, data from both treatment arms were combined for the analysis.

There is an ongoing randomized, clinical trial investigating the effects of depth of anesthesia on a range of outcomes98, including death, myocardial infarction, cardiac arrest, pulmonary embolus, stroke, surgical site infection, ICU length of stay, hospital length of stay, intraoperative awareness, persistent pain and cancer recurrence. Many of these outcomes are tracked with the SATISFY-SOS study, and will therefore be reported for patients enrolled in the ENGAGES study.

It is important to improve our understanding of factors that are associated with an increased incidence of postoperative delirium or perhaps may even mediate an elevated risk for postoperative delirium. The arm/group was included in the model to determine if it was associated with postoperative delirium therefore data is not presented by arm/group.

The ENGAGES study is being conducted in collaboration with complementary trials at the University of California, San Francisco (UCSF) (NCT01983384), the University of Michigan in Ann Arbor and the University of Manitoba in Winnipeg. Some of the outcomes will be analyzed considering data from some or all of these studies, as appropriate. In terms of the practicality of disseminating the EEG-guided protocol in North America and beyond, it will be important to demonstrate the feasibility and impact of the protocol in multiple sites.

The severity of delirium will be scored using the CAM-Severity (CAM-S) metric, which has specifically been shown to be strongly associated with clinically relevant outcomes. Severe delirium was defined as patients with a CAM-S score of 10 or greater (range 0-19).

EEG abnormalities have previously been associated with postoperative delirium

Postoperative disturbances in sleep abnormalities have previously been associated with postoperative delirium. Measures of root mean-squared activity (RMSactivity) was calculated by combining counts (binned in 1-minute intervals) across all three accelerometer axes (X, Y, and Z) from 16:00 on the day of surgery to 6:00 the following day. We quantified inactivity using the number of immobile minutes, defined as the total number of minutes with an RMSactivity count of zero- higher number indicates patient had more time being immobile.

Total of all reporting groups

American Society of Anesthesiologist (ASA) Classification ASA I: Normal Healthy patient ASA II: A patient with mild systemic disease ASA III: A patient with severe systemic disease ASA IV: a patient with severe systemic disease that is a constant threat to life ASA V: A moribund patient who is not expected to survive without the operation ASA VI: A declared brain-dead patient whose organs are being removed for donor purposes

The Functional status of the patient can be divided into POOR (< 4 METs,-unable to walk > 2 blocks on level ground without stopping due to symptoms, eating, dressing, toileting, walking indoors, light housework) or MODERATE /EXCELLENT (> 4 METs, -climbing > 1 flight of stairs without stopping, walking up hill > 1-2 blocks, scrubbing floors, moving furniture, golf, bowling, dancing or tennis, running short distance

Assesses current depression. Range 0 to 24. greater than or equal to 10 indicates major depression and greater than or equal to 20 indicates severe major depression.

The SBT is a screening tool that aids in detecting early cognitive changes associated with dementia disorders. Rage 0 to 28. A score of 0-4 is normal cognition, 5-9 is questionable cognitive impairment, 10 or greater is cognitive impairment consistent with dementia.

The AD8 is quite sensitive to detecting early cognitive changes associated many common dementing illness including Alzheimer disease, vascular dementia, Lewy body dementia and frontotemporal dementia. Range 0 to 8. A score of 0-1 is normal cognition, 2 or greater cognitive impairment is likely to be present.

Assesses functional independence. Range 0 to 100. Less than 20 indicates totally dependent, 20 to 39 indicates very dependent, 40-59 indicates partially dependent, 60 to 79 indicates minimally dependent, 80 to 100 indicates independent.

Instrument assesses independent living skills. Range 0 (low function, dependent) to 8 (high function, independent).

VR-12 is a patient reported global heath measure that is used to assess a patient's overall perspective of their health. Answers are summarized into two scores, a Physical Component Score and a Mental Component Score which then provides an important contrast between the respondents physical and psychological health status. Standardized scale 0 to 100 with 50 representing the population average. A score above 50 is better than the USA average where a score below 50 is worse than the USA average.

VR-12 is a patient reported global heath measure that is used to assess a patient's overall perspective of their health. Answers are summarized into two scores, a Physical Component Score and a Mental Component Score which then provides an important contrast between the respondents physical and psychological health status. Standardized scale 0 to 100 with 50 representing the population average. A score above 50 is better than the USA average where a score below 50 is worse than the USA average.

Participants will have the standard anesthetic protocol.

The hypothesis is that the EEG-guided anesthetic protocol and providing a safety intervention will prevent subsequent injurious falls. Falls will be assessed using the Prevention of Falls Network Europe (ProFaNE) questions. At baseline questions will be asked about preoperative falls, and at 30-days and 1-year postoperatively, questions will be asked about postoperative falls.

The hypothesis is that the EEG-guided anesthetic protocol will improve postoperative quality of life. Patient self-reported Health-related Quality of Life information will be assessed through the Veteran's RAND 12-item Health Survey at baseline and during follow-up (30-day and 1-year).

Duration will be calculated by the number of positive CAM,CAM-ICU or delirium chart reviews.

A total of 1232 patients were randomized (614 EEG guided protocol and 618 control arm). In the EEG guided group 10 patients could not be assessed for delirium (6 comatose, 2 withdrew, 2 early hospital discharge). In the control arm 9 patients could not be assessed for delirium (1 died, 5 comatose, 1 withdrew, 2 early hospital discharge).

The Family Confusion Assessment Method (FAM-CAM) instrument has previously been shown to have good agreement with the CAM and with DSM-IV diagnostic criteria in patients with cognitive impairment and in hospitalized patients.

As measured by the FAM-CAM and patient perceptions

Delirium incidence, duration and severity have all been shown to be associated with other (downstream) clinically relevant outcomes, including mortality, length of ICU stay, length of hospital stay, falls, cognitive decline and functional decline.

Given that postoperative delirium is common and may relate to uncontrolled pain, this has important implications for the assessment and treatment of postoperative pain. We plan to compare patient reported and behavioral pain assessments in both non-delirious and delirious patients.

Postoperative disturbances in sleep abnormalities have previously been associated with postoperative delirium. Measures of root mean-squared activity (RMSactivity) was calculated by combining counts (binned in 1-minute intervals) across all three accelerometer axes (X, Y, and Z) from 16:00 on the day of surgery to 6:00 the following day. Median activity count was calculated from all minutes with nonzero RMS activity within each epoch- higher values indicate more movement.

A total of 84 patients had analyzable data and included in the analysis. Patients were pooled regardless of intervention (EEG guidance or usual care) since the primary outcome was to assess whether using actigraphy could predict delirium regardless of interventions. Therefore, patients were separated by delirious and non-delirious patients.

Routine clinical (i.e. conducted by ICU nursing staff) delirium assessments in the intensive care units (conducted with the CAM-ICU) will be collected when these are available. Comparison will be made on the outcome of the assessment (positive for delirium or negative by delirium) between these routine clinical assessments and the assessments made by the research team. Since the purpose of this is to determine whether clinical staff are picking up episodes of delirium compared to researcher's assessment in all patients regardless of treatment group, data from both treatment arms were combined for the analysis.

Patients who were in the ICU, had a nursing CAM-ICU assessment and researcher's delirium assessment were included in this analysis. Agreement between the instruments was calculated using Kappa agreement.

There is an ongoing randomized, clinical trial investigating the effects of depth of anesthesia on a range of outcomes98, including death, myocardial infarction, cardiac arrest, pulmonary embolus, stroke, surgical site infection, ICU length of stay, hospital length of stay, intraoperative awareness, persistent pain and cancer recurrence. Many of these outcomes are tracked with the SATISFY-SOS study, and will therefore be reported for patients enrolled in the ENGAGES study.

It is important to improve our understanding of factors that are associated with an increased incidence of postoperative delirium or perhaps may even mediate an elevated risk for postoperative delirium. The arm/group was included in the model to determine if it was associated with postoperative delirium therefore data is not presented by arm/group.

Covariated included were pre-selected and considered likely to be associated with postoperative delirium.

The ENGAGES study is being conducted in collaboration with complementary trials at the University of California, San Francisco (UCSF) (NCT01983384), the University of Michigan in Ann Arbor and the University of Manitoba in Winnipeg. Some of the outcomes will be analyzed considering data from some or all of these studies, as appropriate. In terms of the practicality of disseminating the EEG-guided protocol in North America and beyond, it will be important to demonstrate the feasibility and impact of the protocol in multiple sites.

The severity of delirium will be scored using the CAM-Severity (CAM-S) metric, which has specifically been shown to be strongly associated with clinically relevant outcomes. Severe delirium was defined as patients with a CAM-S score of 10 or greater (range 0-19).

A total of 1232 patients were randomized (614 EEG guided protocol and 618 control arm). In the EEG guided group 10 patients could not be assessed for delirium (6 comatose, 2 withdrew, 2 early hospital discharge). In the control arm 9 patients could not be assessed for delirium (1 died, 5 comatose, 1 withdrew, 2 early hospital discharge).

EEG abnormalities have previously been associated with postoperative delirium

Postoperative disturbances in sleep abnormalities have previously been associated with postoperative delirium. Measures of root mean-squared activity (RMSactivity) was calculated by combining counts (binned in 1-minute intervals) across all three accelerometer axes (X, Y, and Z) from 16:00 on the day of surgery to 6:00 the following day. We quantified inactivity using the number of immobile minutes, defined as the total number of minutes with an RMSactivity count of zero- higher number indicates patient had more time being immobile.

A total of 84 patients had analyzable data and included in the analysis. Patients were pooled regardless of intervention (EEG guidance or usual care) since the primary outcome was to assess whether using actigraphy could predict delirium regardless of interventions. Therefore, patients were separated by delirious and non-delirious patients.

Participants will have the standard anesthetic protocol.