①Effects of BIS Index (BIS) monitoring on delirium incidence in Post-anesthesia care unit (PACU) in patients undergoing general anesthesia

②Effects of BIS BIS Index (BIS) monitoring on the quality of nursing care in the Post-anesthesia care unit (PACU)

The effect of intraoperative anesthesia depth monitoring on delirium occurrence and improvement of nursing quality in the post-anesthesia care unit (PACU) remains unclear. We aimed to explore the effect of intraoperative anesthesia bispectral index (BIS) monitoring on delirium occurrence and improvement of nursing quality in the PACU for patients recovering from general anesthesia.

This randomized controlled trial included 120 patients, aged 20-80 years and classified as grades I-III according to the American Society of Anesthesiologists. The BIS-guided group (group B) underwent intraoperative monitoring of BIS anesthesia depth (maintained within the anesthetic range [40-60]). The depth of anesthesia was not monitored in the non-BIS-guided group (group C). The patients' vital signs were recorded at the beginning of the operation (T0), upon entering the PACU (T1), 15 min after extubation (T2), and after leaving the PACU (T3). Delirium score, emergence period (extubation and PACU observation times), and adverse events in the PACU were monitored. The nursing activity score (NAS) was used to evaluate the quality of care.

Inclusion Criteria:

1. age ranging from 20 to 80 years
2. estimated operation time of 2 to 3 h
3. body mass index ≤30 kg/m2
4. normal preoperative heart, liver, lung, and renal function.

Exclusion Criteria:

1. Past cognitive impairment (dementia, cognitive impairment, mental illness or mental disorder)
2. Complex injuries: multiple fractures, chest and abdomen, pelvic and sacral trauma, head trauma, etc
3. Contraindications to intraspinal puncture (coagulation dysfunction, thrombocytopenia, intraspinal space occupation, puncture site infection, etc.)
4. Have a history of acute myocardial infarction or stroke within 3 months
5. Patients with severe liver dysfunction (Child-Pugh C) or renal failure
6. Contraindications to ketamine, such as malignant hypertension