Reduction in anesthesia-related nitrous oxide consumption and environmental footprint via a quality improvement initiative at two quaternary hospitals in São Paulo, Brazil.

Abstract

Purpose: Climate change is increasingly recognized as an emergency, particularly within the health care sector. Reducing nitrous oxide (N₂O) usage is critical for mitigating anesthesia-related greenhouse gas emissions, a significant environmental threat. We aimed to evaluate the effectiveness of implementing quality improvement (QI) strategies to reduce the carbon footprint in anesthesia practice at two quaternary hospitals in São Paulo, Brazil, São Luiz Anália Franco Hospital and and São Luiz Itaim Hospital. We aimed to lower N₂O use in inhalational anesthesia, targeting a 75% reduction in carbon footprint over 16 weeks.

Methods: Through a QI initiative, we restricted N₂O usage to inhalational induction in pediatric anesthesia only. Employing quality and safety tools, we implemented educational strategies to limit N₂O application and minimize waste from the central anesthesia workstation pipeline. We calculated greenhouse gas emissions as carbon dioxide equivalents (CO₂e), monitored adverse events, and tracked sedative agents use both before and after the interventions.

Results: From January to August 2024, our project encompassed 30,217 anesthetics over 32 weeks. Among these, 6,806 involved inhalational anesthesia, with 624 (9%) involving N₂O. In adult patients, baseline data over 16 weeks prior to the intervention showed an average N₂O usage rate of 11%, which decreased significantly to 2% postintervention (P < 0.001). In pediatric patients, N₂O usage dropped from 62% to 46% following the intervention (P < 0.001). The emissions per anesthetic using N₂O declined from 132 kg (lower control limit [LCL], 98 kg; upper control limit [UCL], 167 kg) to 23 kg (LCL, 9 kg; UCL, 38 kg) following our interventions.

Conclusions: By optimizing N₂O usage through educational and judicious interventions, our QI initiative achieved a 82.5% postintervention reduction in anesthesia-related institutional CO₂e. Moreover, we fostered a significant cultural shift, enhancing accountability for health care initiatives aimed at environmental protection.