Environmental and patient safety outcomes of a health-system Green Anesthesia Initiative (GAIA): a retrospective observational cohort study.

Summary

A health-system-wide initiative (GAIA) reduced anesthesia-related greenhouse gas emissions by decreasing nitrous oxide use, favoring lower-impact volatile agents, and increasing total intravenous anesthesia, without worsening patient outcomes. Retrospective multivariable analyses across ~92,891 cases showed environmental benefits with maintained clinical safety.

Key Findings

• System-wide GAIA implementation reduced anesthesia-attributable CO2e emissions post-intervention versus pre-intervention.
• Intervention strategies included nitrous oxide reduction, preferential use of less environmentally harmful volatile agents, and increased intravenous anesthesia.
• No deterioration in patient outcomes was observed after implementation based on multivariable modeling.
• Large dataset analyzed: 45,692 cases pre-intervention and 47,199 cases post-intervention across a single academic medical center.

Clinical Implications

Implement system-wide reductions in nitrous oxide, preferential use of lower-GWP volatiles, and more TIVA to reduce CO2e without compromising patient safety. Incorporate environmental metrics into anesthesia quality dashboards.

Limitations

• Single-center retrospective design with potential unmeasured confounding
• Environmental and clinical outcomes not randomized; generalizability may vary by infrastructure and practice patterns

Future Directions

Prospective multicenter implementation studies with standardized environmental metrics and patient-centered outcomes; evaluation of cost-effectiveness and real-time carbon dashboards.