Greenhouse Gas Emissions Significantly Lower With Regional vs General Anesthesia

By Linda Carroll

June 17, 2020

(Reuters Health) - Switching from general to regional anesthesia may substantially cut greenhouse gas emissions and help reduce global warming, a new study suggests.

Researchers determined that if all the hip and knee arthroplasties performed in the U.S. in 2009 had been done with regional anesthesia, the nation could saved the equivalent in greenhouse gas emissions of 3,260,000 pounds of coal burned, according to the report published in Regional Anesthesia and Pain Medicine.

"The take home message from our study is that anesthesiologists have the opportunity to make a personal difference in decreasing greenhouse gases in their practices through the use of regional anesthesia," said coauthor Dr. Christopher Wu, a clinical professor of anesthesiology at the Hospital for Special Surgery at Weill Cornell Medicine in New York. "In this day and age we are all trying to make personal contributions to decreasing greenhouse gases."

Unlike general anesthesia, regional anesthesia doesn't use volatile halogenated agents such as desflurane or nitrous oxide, Wu explained.

In 2019, the Hospital for Special Surgery decided to use regional anesthesia in as many hip and knee replacements as possible. Out of the 10,485 procedures carried out at during 2019, just 419, or 4%, were done under general anesthesia.

By using general anesthesia less often than the average rate for the U.S., which is 75%, Wu and his colleagues estimate that the Hospital for Special Surgery saved the equivalent of 26,900 pounds of coal burned, 2,750 gallons of gasoline consumed, or 60,500 miles driven by an average passenger vehicle.

"The impact of anesthetics on greenhouse gases is pretty well established," said Dr. Andrew Leibowitz, chair of the department of anesthesiology, perioperative and pain medicine at The Mount Sinai Health System in New York. Most anesthesiologists in academic hospitals use regional anesthesia whenever it's appropriate, he said, but that's not always the case nationwide.

Regional anesthesia is "very safe and effective for patients and most are very accepting of it," he said. "It's a mystery to me why almost half the country insists on doing general anesthesia" when regional anesthesia would be possible.

"Having said that, there are ways you can do general anesthesia that would not use those gases and be safe for the environment," Leibowitz said. "Total intravenous anesthesia is very effective and safe."

That said, the gases used in anesthesia aren't the only environmental issues at the nation's hospitals, Leibowitz said.

"Hospitals make an enormous amount of non-biodegradable waste," Leibowitz said. "They do very little recycling. It's kind of shocking. I'm an environmentalist at home where we are very careful to (recycle). Here we make around 10 bags of waste per operation and I have no idea what happens to it."

What goes into those bags?

"It includes the disposable thick paper covering of the OR table, the outer paper coverings of all the instrument trays, everyone's gloves, gowns, masks, maybe the patient's disposable paper gown and then the various "dirty" things like lap pads, 4x4's, disposable intubation equipment, used IV bags, vials that contained medication, etc. and then also the laundered blankets and sheets," Leibowitz said. "So even a simple operation like a knee arthroscopy or cholecystectomy makes three to four very large garbage bags of waste and a more complex operation like a liver transplant could make 10-15 bags."

SOURCE: Regional Anesthesia and Pain Medicine, online June 16, 2020.