Major B.C. trauma hospital switches anesthetic gas to reduce carbon footprint

Canada's health-care system accounts for about five per cent of greenhouse gas emissions in the country, but anesthesiologists at Royal Columbian Hospital in New Westminster, B.C., are moving to curb their surgical unit's carbon footprint.

Patients going under the knife at RCH will no longer be put to sleep with desflurane — a highly potent pollutant that RCH anesthesiologists say has 25 times more greenhouse gas emissions than its alternative, sevoflurane. 

The hospital, one of B.C.'s biggest and busiest, will also return to the manufacturer vaporizers used to administer the gas.

Eagle Ridge Hospital, a smaller acute care facility in neighbouring Port Moody, will also ban the anesthetic.

Dr. Cedric Ho, an anesthesiologist at Royal Columbian and Eagle Ridge hospitals, acknowledges both desflurane and sevoflurane have global warming potential, but the differences between their climate impacts are stark. 

"If I were to give you the [desflurane] anesthetic for two hours, it would be the same as if you and I got into an SUV and drove up to Kamloops [a 350-kilometre drive]," said Ho. "Whereas the other option is like a short trip, just locally."

Studies show treating patients with desflurane does not have a significant benefit over other alternatives. Ho referred to individual preferences among anesthesiologists.

"It's just like how we all might have a different brand that we like for diet cola, but really, in many ways, there's not much of a difference."

Royal Columbian Hospital follows a handful of surgical units nationwide that have phased out desflurane, including Health Sciences North (HSN) in Sudbury, Ont.

Dr. Sanjiv Mathur, a physician at HSN, said the hospital managed to eliminate 700 annual tonnes of carbon dioxide since making the complete switch to sevoflurane.

"[It's] the equivalent of getting into a 28-mile-per-gallon car, driving four times to the moon and back," said Mathur. 

Mathur co-authored a report examining the climate impacts of anesthetic gases and attributes those preferences to marketing.

"It was marketed as being faster for patient wake-ups, so the reality was that never really panned out in more rigorous studies," said Mathur.

Mathur said there were no differences in patient outcome and recovery after switching to sevoflurane.

Ho also points out how more than 95 per cent of anesthetic gases are not metabolized by the body. 

"Everything we give the patient eventually comes back out," said Ho. "But they're actually just allowed to go up essentially like a chimney up into the atmosphere out of the top of the hospital."

Ho acknowledges there are solutions to capture, scavenge and recycle desflurane, but insists the best solution is not to use it at all.

Dr. Kai Chan, a UBC professor and research chair at the Institute for Resources, Environment and Sustainability, said operating rooms moving away from desflurane is a small but important step. 

"It's been known for over a decade that desflurane has really high greenhouse gas impacts, and it's taken quite a while for some hospitals to switch," said Chan. 

Growing movement of health-care providers looking out for climate change'

Mathur said he is working with the Citizens Climate Lobby to ban desflurane, possibly through carbon pricing. He has done research on how legislation can work to phase out the drug.

"I published a paper showing that if you apply the current carbon pricing mechanism in Canada to these (gas) agents, desflurane would no longer be competitive, and hospitals probably just won't buy it."

He says he wants Canada to be the first country to ban desflurane and follow the national effort of the U.K.'s NHS system to reduce the country's health-care footprint. 

Mathur's research into the climate impacts of anesthetic gases began as the Canadian Medical Association and other medical publications called on physicians to look for ways to minimize health care's carbon footprint.

"Once I figured out that it was actually a threat to my kids' future, I started to examine what we could really do," said Mathur. "I was shocked to find out that the gases that are used every day — desflurane and sevoflurane — are, in fact, very high carbon footprint agents."

According to Chan, RCH moving away from desflurane represents a "growing movement of health-care providers looking out for climate impacts. He is calling for a framework to include climate considerations in health-care operations. 

"If all industries were responsible for all major greenhouse gases, then this would be something that already would have been accounted for," said Chan.

Ho says it would be difficult to ban a substance that is still considered effective and safe, but he hopes RCH's ban on desflurane will ripple across other hospitals.

"Our hope is that other groups will look at this decision and say, 'Well, that was simple.'"