Environmental considerations for inhalant anesthesia

Tatiana Henriques Ferreira, DVM, PhD, MSc, DACVAA, a clinical assistant professor at the University of Wisconsin-Madison School of Veterinary Medicine, and Marlis Rezende, DVM, PhD, MSc, DACVAA, an associate professor of anesthesia and analgesia at Colorado State University College of Veterinary Medicine and Biological Sciences in Fort Collins, co-presented a lecture on inhalant anesthesia vs total intravenous anesthesia at the 2025 North American Veterinary Community (NAVC) SkillShop in Orlando, Florida. In a dvm360 interview, Ferreira discusses the environmental impacts of inhalant anesthesia use, including how these gasses affect air and water quality.

The following is a transcript of the video:

Tatiana Henriques Ferreira, DVM, PhD, MSc, DACVAA: Healing anesthetics are potent greenhouse gasses, so we do worry about the impact of those gasses in our environment. So trying to minimize that by decreasing oxygen flow during anesthesia is critical, right? Like, I know a lot of people jump to go into 1-2 liters per minute automatically, which is not necessarily required for all the patients. So when you do this, you definitely minimize the exposure of the environment to greenhouse gasses.

Even though we think about inhaling anesthetics as being gas or eliminated [into] and affecting the air, [they] do have an effect on the water as well, especially if you're using sevoflurane. So sevoflurane does have a higher metabolism…rate compared to isoflurane. Isoflurane can be, like, very low, like less than point 2%. However, so it can be 2% to 5% metabolized, and it generate metabolites in byproducts that can stick to the environment for a long, long time. And then after metabolism, that's going to be excreted in urine, and there you go.

So you have water contamination as well as air contamination. And like I said, these metabolites are really hard to get rid of, and they stick to the environment for a long time. So we definitely have to keep that in in mind as well when you're using inhalants.