Meta-Analysis Finds No Significant Difference in Postoperative Delirium Risk Between Volatile and Propofol-Based Anesthesia

A meta-analysis published in the *Journal of Clinical Anesthesia* found no clear difference in the risk for postoperative delirium between patients receiving volatile anesthesia and those receiving propofol-based intravenous (IV) anesthesia, according to a study led by Jibran Ikram, MD, of the Cleveland Clinic Foundation in Ohio. The research, which analyzed 29 randomized trials involving over 11,000 patients, concluded that while small, inconsistent cognitive differences favored propofol-based anesthesia, these were unlikely to be clinically meaningful.

What Did the Study Find?

The study evaluated neurocognitive outcomes after surgery using volatile anesthesia versus propofol-based IV anesthesia. Researchers conducted a systematic review and meta-analysis of trials up to November 2025, focusing on delirium diagnosed within seven days of surgery and delayed neurocognitive recovery within 30 days. The primary outcome showed no significant difference in delirium risk between the two groups (11 trials; 8,818 patients; I² = 55%).

However, patients receiving volatile anesthesia had a 35% higher risk for delayed neurocognitive recovery compared to those receiving propofol-based IV anesthesia (15 trials; 2,423 patients; P = .01; I² = 66%). Pooled Mini-Mental State Examination (MMSE) scores were also 1.5 points lower after volatile anesthesia, though researchers noted this difference was not clinically significant.

Why Does This Matter for Patients and Clinicians?

The findings challenge the assumption that propofol-based IV anesthesia offers superior cognitive protection post-surgery. “The evidence does not support choosing intravenous anesthesia solely to reduce postoperative delirium or improve postoperative cognition,” the researchers stated. This could influence clinical guidelines, as anesthesiologists often weigh factors like recovery time and patient safety when selecting anesthesia types.

Dr. Ikram emphasized that the study’s results highlight the need for further research into individualized approaches to anesthesia, given the high variability in trial designs and patient populations. “The heterogeneity in surgical procedures and baseline patient characteristics limits the generalizability of these findings,” he said.

What Are the Study’s Limitations?

The analysis faced challenges due to the diversity of trials, with most including fewer than 200 patients per group. Researchers noted high heterogeneity (I² values up to 98%) in cognitive outcome assessments, which varied by tool and timing. Additionally, the study did not report funding sources or conflicts of interest, though the authors declared no financial ties.

“The lack of standardized cognitive testing across trials makes it difficult to draw definitive conclusions,” said Dr. Natalie Singh, a board-certified internal medicine physician and health editor. “Clinicians should interpret these results alongside patient-specific factors and ongoing clinical judgment.”

What’s Next for Anesthesia Research?

The study underscores the complexity of postoperative cognitive outcomes, which can be influenced by age, surgery type, and preexisting conditions. Future research may focus on biomarkers or personalized anesthesia protocols to mitigate delirium risk. For now, the findings suggest that the choice between volatile and propofol-based anesthesia should prioritize other clinical considerations, such as patient comfort and procedural efficiency.