Follow-up Visits

In the PACU, participants are screened using the Confusion Assessment Method for the Intensive Care Unit (CAM-ICU)^34,35,36 at 15 and 30 minutes after tracheal extubation and at discharge from PACU (within 1 hour after tracheal extubation). Delirium is defined as a positive CAM-ICU test result at either of these 3 time points. The Richmond Agitation Sedation Scale (RASS) is performed before the CAM-ICU test to assess the depth of sedation.³⁷ If the RASS score is −4 or −5, the patient is insufficiently aroused for delirium assessment. Researchers will repeat an independent assessment at the next predetermined point. If the RASS score is greater than −4, the CAM-ICU test will be performed. If RASS scores remain −4 or −5 beyond 1 hour after tracheal extubation, the patient will no longer receive the CAM-ICU test in the PACU, and the primary outcome will be recorded as missing data. Before discharge from PACU, EEG monitoring (5 minutes) and blood draw are conducted for participants.

In the hospital wards, participants are reassessed for delirium from postoperative days 1 to 3 in the morning and the afternoon. The visual analog scale is used to measure the level of pain at postoperative days 1 to 3. Participants complete measures of depression (9-item Patient Health Questionnaire),³⁰ anxiety (7-item Generalized Anxiety Disorder Scale),³¹ and insomnia (Insomnia Severity Index)³² at postoperative day 3. Trained researchers conduct assessments blinded to the allocation.