Studying Light Versus Deep General Anesthesia to Reduce Delirium and Cognitive Decline After Major Surgery in Older Adults

What this Trial Is About

Researchers are studying the effects of light versus deep general anesthesia in older adults undergoing major surgery to see if lighter anesthesia can reduce postoperative delirium, cognitive decline, and disability. Delirium is a common and serious complication in older surgical patients, causing distress and long-term health issues. This trial targets older adults aged 65 and above, including Indigenous and Pacific patients aged 55 and above, undergoing non-heart and non-brain major surgery under total intravenous anesthesia TIVA. Participants will be randomly assigned to two groups receiving either light or deep general anesthesia guided by processed electroencephalography pEEG brain monitors, such as the Bispectral Index BIS or Patient State Index PSI. The anesthesiologist will adjust anesthetic drugs based on brain wave readings from 10 minutes after anesthesia induction until awakening. The study limits certain drugs that interfere with brain monitoring. Care during surgery follows standard protocols except for the anesthesia depth adjustment. During the study, participants will be assessed twice daily for up to three days after surgery to detect delirium and monitored further if delirium occurs. Longer-term follow-ups at 90 days and one year will evaluate cognitive, physical function, and survival outcomes. The study aims to understand if anesthesia depth affects delirium rates and longer-term brain health, with careful tracking of participant health and safety throughout the process.

Depth of Anesthesia on Postoperative Delirium and Cognitive After Surgery