A Randomised Controlled Trial to Reduce Postoperative Delirium Through Reduction in Intraoperative EEG Suppression in Older Surgical Patients Undergoing Major Noncardiac Surgery
Overview
- Phase
- N/A
- Intervention
- Not specified
- Conditions
- Delirium
- Sponsor
- University of California, San Francisco
- Enrollment
- 205
- Locations
- 1
- Primary Endpoint
- Intraoperative EEG Suppression
- Status
- Completed
- Last Updated
- 6 years ago
Overview
Brief Summary
Recent limited evidence suggests that anesthetic depth may influence postoperative cognitive outcomes, however, the mechanism between this association is unclear.
Detailed Description
Recently, it has been proposed that use of a processed electroencephalogram (EEG) monitor during surgery may be associated with a lower rate of postoperative delirium. In fact, some suggest that older patients undergoing surgery should routinely be monitored with an anesthetic depth monitor to allow the titration of anesthetics or sedation medications to lighter levels to promote better postoperative cognitive outcomes. Recent studies, including preliminary results from our group, have demonstrated electroencephalogram (EEG) suppression to be an independent risk factor for postoperative delirium. Prior studies that have focused on risk prediction have shown age and prior cognitive impairment to be the most consistent risk factors for postoperative delirium. However, as of yet, no clinical trial has identified a relationship whether use of processed EEG monitor resulted in a reduction of incident postoperative delirium through a reduction in EEG suppression, with proper consideration of patients' baseline cognitive status as a potential moderator. Additionally, use of anesthetic depth monitor to keep patients' anesthetic depth above a specified value has never been validated or proven to be feasible or safe. Accordingly, the investigators plan an exploratory study to: 1) determine whether the use of processed EEG to keep anesthetic depth above a specified level, results in a reduction in EEG suppression when compared to standard anesthetic care, 2) to determine whether preoperative level of cognitive function moderates the effect of group assignment on EEG suppression, and 3) to determine the feasibility and safety of using processed EEG-guided to keep patients' anesthetic depth above a specified value. A secondary aim was to determine the effect size for the intervention to reduce postoperative delirium for subjects with and without preoperative cognitive impairment for a future trial.
Investigators
Eligibility Criteria
Inclusion Criteria
- •65 years and older of age undergoing non-cardiac surgery, requiring hospital stay of 2 or more days.
Exclusion Criteria
- •patients who are not fluent in English or cannot provide informed consent
- •patients who may not tolerate either light or deep anesthesia (history of heart failure, coronary artery disease, substance abuse)
- •history of intraoperative recall or awareness during anesthesia
- •pathologies of the brain which may affect EEG monitoring
- •patients who are anticipated to have consecutive surgery within 3 days of first procedure
- •patients who have had surgery with general anesthesia in the past 30 days
Outcomes
Primary Outcomes
Intraoperative EEG Suppression
Time Frame: Patients will be monitored by processed EEG intraoperatively, for the duration of surgery
Intraoperative EEG suppression will be measured by processed EEG monitor
Secondary Outcomes
- Patient intraoperative awareness and recall(Intraoperative recall and awareness will be measured within 72 hours after end of surgery)
- Anesthesiologists' adherence to assigned processed EEG index in the interventional group(Anesthesiologists complete self-report within 72 hours after end of surgery. This outcome measure is collected once for each patient through study completion, an average of 2 years.)
- Intraoperative systolic and diastolic blood pressure(During surgery)
- Postoperative delirium(Daily for three postoperative days.)
- Patient movement(During surgery)
- Preoperative level of cognitive function(Up to one week before surgery)
- Intraoperative heart rate(During surgery)