TOPLINE

In adults who underwent elective neurovascular surgery, remimazolam-based total intravenous anesthesia (TIVA) with flumazenil reversal was noninferior to propofol-based TIVA for postoperative delirium. However, the incidence of delirium was lower than expected, which warrants careful inference.

METHODOLOGY

• Researchers conducted a double-blind, randomized trial to assess whether remimazolam-based TIVA with flumazenil reversal was noninferior to propofol-based TIVA for postoperative delirium after neurovascular surgery. 
• The analysis included 686 adults aged 19 years or older (mean age, 58.4 years; 31.8% women) who were scheduled for elective neurovascular craniotomy at a center in Seoul between November 2023 and November 2025. Patients had an American Society of Anesthesiologists physical status of 1-3. 
• Patients were randomly assigned to receive either remimazolam (induction 0.1-0.2 mg/kg; infusion 1-2 mg/kg/h) or propofol (effect-site target-controlled infusion 3-5 µg/mL). Both groups received remifentanil, and the remimazolam group received flumazenil at emergence. 
• The primary outcome was the occurrence of delirium within 5 days after surgery, assessed twice daily using validated tools. Remimazolam was judged noninferior if the upper limit of the 95% CI for the difference remained below 10 percentage points. 
• Secondary outcomes included intraoperative hypotension, emergence and airway events, early postoperative symptoms, and cognitive and functional outcomes up to 3 months. 

TAKEAWAY

• Delirium within 5 days of surgery occurred in 12.8% of patients in the remimazolam group and in 10.8% of those in the propofol group. The risk difference of 1.97 percentage points (95% CI, -2.85 to 6.80) met the noninferiority margin (P < .001 for noninferiority). 
• A post hoc analysis using a stricter margin of 3.6 percentage points did not support noninferiority. 
• Patients in the remimazolam vs propofol group spent less time with mean arterial pressure below 65 mm Hg (median, 0 vs 7.5 mm Hg·min) and were extubated in the operating room more often (85.2% vs 67.3%; P < .001 for both). 
• Nausea and vomiting at 6 hours and airway events were more common in the remimazolam group. Severity of delirium, cognition, and function did not differ between groups. 

IN PRACTICE

"[The] present findings characterise remimazolam-based TIVA with flumazenil reversal rather than remimazolam alone," the researchers reported.

SOURCE

The study was led by Jeayoun Kim and Seungwon Lee of Sungkyunkwan University School of Medicine in Seoul, Republic of Korea. It was published online on October 29 in the British Journal of Anaesthesia.

LIMITATIONS

Delirium occurred less often than expected in the propofol group, which made the noninferiority margin relatively wide. Assessments on day 0 after surgery were missed in 9.2% of patients, which may have overlooked short and self-resolving episodes of delirium. The study was conducted at a single center, limiting generalizability.

DISCLOSURES

The study received funding from the Korean Ministry of Science and Information and Communication Technology, through the National Research Foundation of Korea. The authors declared having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.