EEG Guidance of Anesthesia (ENGAGES-CANADA) (ENGAGES)

Protocol for the Electroencephalography Guidance of Anesthesia to Alleviate Geriatric Syndromes (ENGAGES-CANADA) Study: a Pragmatic, Randomized Clinical Trial

ENGAGES CANADA is a parallel study to the ENGAGES study which has been published in JAMA, DOI:10.1001/jama.2019.5161. Due to the difference in practice models and types of anesthesia principles, ENGAGES CANADA is an important study. Delirium is a relatively common postoperative complication in the geriatric population, affecting 20% to 70% of surgical patients over the age of 60. Delirium manifests as confusion, inattention and the inability to think logically, and may affect the patient's postoperative healing and rehabilitation. It is associated with persistent cognitive decline, longer hospital stay, increased incidence of injurious falls, and increased mortality. Patients undergoing major cardiac surgery are at a significant risk of postoperative delirium. To date, there is no proven method to prevent postoperative delirium in this patient population and often delirious events remain unrecognized. Randomized controlled studies in diverse surgical patient populations suggest that intraoperative electroencephalography (EEG) guidance during general anesthesia may decrease postoperative delirium and adverse postoperative outcomes. Patients who experience postoperative delirium report persistently decreased quality of life and it is a risk factor for incident psychiatric disorders and psychotropic medication use. One potential key mechanism in the relationship between delirium and incident psychiatric illness may be the experience of dissociation (disturbed awareness, impaired memory, or altered perceptions) in the perioperative period in those who are delirious. The co-occurrence of psychiatric illness and delirium can put older adults at greater risk of negative long terms effect such as functional decline. This study will compare the effectiveness of two anesthetic protocols in reducing postoperative delirium and postoperative health-related quality of life in a high risk population.We expect that EEG-guided anesthetic management of patients during their operative procedure will result in improved health-related outcomes, specifically decreased incidence of postoperative delirium and improved postoperative mental and physical health outcomes.

anesthesia, delirium, surgery, electroencephalography, burst suppression, PTSD, anxiety, depression, falls

Anesthesia practitioner is not blinded to intervention. Subject is blinded and primary outcome assessor is blinded to intervention.

Patients will undergo standard anesthesia and will be blinded to EEG-based data, as per standard of care in this patient population.

Practitioners will follow the EEG-Guided protocol to limit the incidence of EEG burst suppression by decreasing administration of anesthesia. The EEG-guided protocol is suggestive rather than prescriptive, and practitioners will exercise judgment depending on the clinical situation.

Incidence of delirium will be compared between the Control Group and the EEG-Guided Group as measured by the numbers of positive Confusion Assessment Method (CAM) or CAM for intensive care unit (CAM-ICU) scores, coupled with Chart Review.

Incidence of mortality (%) will be compared between the Control Group and the EEG-Guided Group at 30 days and at 1 year

Number of falls will be recorded by patient interview at 30 days and 1 year, compared between the Control Group and the EEG-Guided Group.

Time (days) measured between the first and last positive CAM assessments and compared between the Control Group and the EEG-Guided Group.

Severity of delirium will be compared between the Control Group and the EEG-Guided Group. As assessed by the CAM-S severity score

The overall incidence of delirium as assessed by CAM vs the incidence of falls by an adjusted regression model.

The overall incidence of delirium as assessed by CAM vs quality of life as assessed by the PROMIS Global Health measure, by an adjusted regression model.

A regression model will be used to assess independent predictors of dissociation as assessed by the PDEQ measure, and mental health outcomes associated with perioperative dissociation.

A regression model will be used to assess independent predictors of PTSD as assessed by the PDI measure.

Depth of anesthesia measured by BIS, Medline, or MASIMO monitors vs mortality rate by an adjusted regression model.

Predictors of Post-Traumatic Stress Disorder (PTSD) using the Post-Traumatic Checklist for DSM-5 (PCL-5).

A regression model will be used to assess independent predictors of PTSD as assessed by the PCL-5 measure. This score predicts the risk of PTSD from 0, negligible risk, to 80, extremely high risk of PTSD in patients.

Undesirable intraoperative movement, awareness with recall, complications such as major blood loss and transfusions, stroke, sternal wound infection, sepsis, dialysis, prolonged intubation

Inclusion Criteria: Adults 60 years or older; Competent to provide informed consent; Undergoing elective cardiac surgery requiring cardiopulmonary bypass. Exclusion Criteria: Unable to provide informed consent; Preoperative delirium; Unable to participate adequately in delirium screening including those who are blind, deaf, illiterate or not fluent English or French; History of intraoperative awareness

Deschamps A, Saha T, El-Gabalawy R, Jacobsohn E, Overbeek C, Palermo J, Robichaud S, Dumont AA, Djaiani G, Carroll J, Kavosh MS, Tanzola R, Schmitt EM, Inouye SK, Oberhaus J, Mickle A, Ben Abdallah A, Avidan MS, Clinical Trials Group CPA. Protocol for the electroencephalography guidance of anesthesia to alleviate geriatric syndromes (ENGAGES-Canada) study: A pragmatic, randomized clinical trial. F1000Res. 2019 Jul 23;8:1165. doi: 10.12688/f1000research.19213.2. eCollection 2019.