What gas anesthetic is commonly used in rodents and can be delivered by chamber or face mask?

• A. Isoflurane
• B. Sevoflurane
• C. Halothane
• D. Desflurane

Answer: (A)

Inhalant anesthetics used for small mammals are given through a sealed chamber or a face mask, allowing easy control of depth by adjusting the vapor concentration. Isoflurane fits this role best in rodent work because it’s inexpensive, widely available, and produces smooth, controllable anesthesia with minimal metabolism, making it easy to titrate and quickly recover after procedures. It works well whether you induce in a chamber and maintain with a mask, which is common in lab settings.

Halothane is older and carries a higher risk of liver toxicity, so it’s largely out of favor. Desflurane tends to irritate airways and requires specialized equipment, making it less practical for routine rodent use. Sevoflurane is valued for rapid induction and less irritation, but it is more expensive, so many facilities default to isoflurane as the standard option.