Greener Anesthesia Slashes Operating Room Emissions Nearly in Half While Cutting Costs 40%

Operating rooms are among the most resource-intensive spaces in any hospital, and the anesthetic gases that keep patients safely asleep during surgery carry a hidden climate cost that has long troubled sustainability experts. Now, a large study presented at the ANESTHESIOLOGY 2026 annual meeting in San Diego suggests that hospitals can dramatically shrink that footprint with nothing more than practical changes to everyday anesthesia practice. Researchers at a six-site academic health system in Virginia found that by adjusting which anesthetic gases clinicians reached for, reducing waste from fresh gas flows, and giving anesthesiologists clear feedback about their own emissions, the institution cut anesthetic-related greenhouse gas emissions by 45 percent per procedure while reducing spending on inhaled anesthetics by nearly 40 percent, all without any measurable decline in patient safety or quality of care.

The scale of the intervention is notable. The study, led by Etta Hanlon, a researcher at Virginia Tech Carilion School of Medicine in Roanoke, compared anesthetic use, estimated emissions, costs, and patient outcomes in 2021 with results from January 2022 through October 2025, after the health system began implementing its changes. In total, the analysis covered 145,917 anesthetic episodes, making it one of the larger real-world assessments of sustainable anesthesia practice to date. Average total emissions dropped from 57.6 kilograms of carbon dioxide equivalent per anesthetic episode in 2021 to 31.6 kilograms after the intervention, a reduction of 45 percent. By late 2025, the health system had surpassed its original goal of cutting emissions by half.

The climate problem stems from the chemistry of the gases themselves. Some inhaled anesthetics, particularly desflurane and nitrous oxide, are potent greenhouse gases that trap heat in the atmosphere far more effectively than carbon dioxide, and they are typically vented from operating rooms into the atmosphere after exhalation by patients. Desflurane, a heavily fluorinated ether, has an especially large global warming potential, which has led health systems in several countries to restrict or phase out its routine use. Nitrous oxide, meanwhile, is both a greenhouse gas and an ozone-depleting substance, and much of what is delivered through hospital piping systems can leak before it ever reaches a patient. Reducing reliance on these agents is therefore one of the most direct levers a hospital can pull to lower the carbon footprint of surgery.

In the Virginia health system, the shift was visible in the prescribing patterns themselves. Desflurane use fell sharply, from 23.8 percent of cases in 2021 to 9.81 percent after the intervention, while the use of sevoflurane, a less climate-damaging inhaled agent, increased from 82.4 percent to 93.1 percent of cases. The health system also encouraged greater use of intravenous anesthesia, which produces no anesthetic gas emissions at all, and reduced fresh gas flow rates during maintenance of anesthesia, a technical adjustment that limits the volume of carrier gas and anesthetic agent wasted during a procedure. These are not exotic measures. They rely on drugs and equipment that most operating rooms already have, which is precisely why the researchers argue that greener anesthesia does not require costly new technology.

A central component of the effort was clinician feedback. Neil Macdonald, chair of the Department of Anesthesiology at Carilion Clinic and associate professor at the Virginia Tech Carilion School of Medicine, helped establish the feedback program, which included individualized emissions reports designed to support informed clinical decision making. By showing each anesthesiologist the estimated climate impact of their own practice, the program turned an abstract environmental problem into a concrete, personal metric that clinicians could act on. This kind of audit-and-feedback approach has proven effective in other areas of quality improvement in medicine, and the Virginia results suggest it can work equally well for sustainability goals, where the environmental consequences of individual choices are usually invisible at the point of care.

The financial results were as striking as the environmental ones. Spending on inhaled anesthetics fell from 628,588 dollars in 2021 to 379,010 dollars in 2024, a reduction of nearly 40 percent. The savings follow directly from the clinical changes, since desflurane is considerably more expensive than sevoflurane, and wasting less fresh gas means purchasing less of it. For hospital administrators weighing sustainability initiatives against budget pressures, the study offers a rare case in which the greener option is also the cheaper one, a combination that could accelerate adoption well beyond a single health system.

Perhaps the most important finding, however, is what did not change. The researchers found that patients continued to recover from surgery safely, with no increase in recovery room stays, hospital stays, breathing tube reinsertion, intraoperative awareness, or postoperative nausea and vomiting after the changes were implemented. These outcomes matter because they address the central concern any clinician would raise about altering anesthetic practice: that patient care might suffer. Anesthetic selection and gas flow rates are clinical decisions with real physiological consequences, and the study indicates that shifting toward lower-emission practice did not compromise recovery in any of the measures tracked across nearly 146,000 procedures.

Our findings show that hospitals can take meaningful steps to reduce the environmental impact of surgery without compromising safety or quality, said Hanlon. By making practical changes in anesthetic selection, reducing waste and giving anesthesiologists clear feedback, we reduced emissions and costs while maintaining strong patient outcomes. The framing matters, because it positions sustainability not as an additional burden on already stretched surgical teams but as a set of behind-the-scenes adjustments that patients never need to think about. Patients should not have to choose between environmentally responsible healthcare and safe, high-quality care, said Sara Wohlford, director of sustainability at Carilion Clinic. These are changes health systems and clinicians can make behind the scenes, allowing patients to benefit from more sustainable care without having to do anything differently.

The broader context gives these findings urgency. Healthcare is a major contributor to greenhouse gas emissions globally, and if the sector were a country, its emissions would rank among the largest in the world. Within hospitals, operating rooms stand out for their intensity of resource use, consuming large volumes of anesthetic gases, energy, and single-use supplies. Because anesthetic gases are vented directly to the atmosphere, they represent an emissions stream that cannot be captured or offset easily, making source reduction the only realistic strategy. The Virginia experience suggests that a coordinated program of drug selection, waste reduction, and clinician engagement can deliver deep cuts in that stream within a few years, using existing infrastructure and clinical judgment rather than capital investment.

As health systems worldwide face growing pressure to account for their carbon footprints, the study offers a template that others can adapt. The interventions were deliberately mundane: prefer one gas over another, turn down the fresh gas flow, show clinicians their own numbers. Yet applied consistently across six surgical sites and nearly 146,000 anesthetic episodes, they halved the climate impact of anesthesia care and returned hundreds of thousands of dollars to the institution, with patient outcomes intact. The researchers note that meeting presentations may contain updated data beyond what was available when the underlying abstract was submitted, and the findings will continue to be refined as the program matures through late 2025. Even so, the direction is clear. The gases that put patients to sleep need not warm the planet, and the operating room of the near future may prove that the greenest choice and the safest choice are increasingly the same one.

Subject of Research: Reducing anesthetic greenhouse gas emissions and costs through changes in anesthetic practice across six surgical sites

Article Title: Greener anesthesia cuts operating room emissions in half, slashes anesthetic costs nearly 40%

Article References: Greener anesthesia cuts operating room emissions in half, slashes anesthetic costs nearly 40%. Original publication (Bibliographic details unavailable.)

Image Credits: AI Generated

DOI: Not provided

Keywords: anesthesia, greenhouse gas emissions, desflurane, sevoflurane, operating rooms, sustainable healthcare, Carilion Clinic, ANESTHESIOLOGY 2026, nitrous oxide, carbon footprint, patient safety, healthcare sustainability