Which volatile anesthetic has a pungent odor and requires a vaporizer?

• A. Desflurane
• B. Sevoflurane
• C. Isoflurane
• D. Nitrous oxide

Answer: (A)

Desflurane stands out because it has a distinctly pungent odor that can irritate the airways, making induction or emergence more challenging in some patients. In addition, it requires a specialized heated, pressurized vaporizer to deliver the correct concentration. Its very low boiling point and high vapor pressure mean a standard vaporizer cannot reliably vaporize and regulate the dose, so a dedicated desflurane vaporizer is used to maintain precise delivery. Sevoflurane, by contrast, has a pleasant, nonpungent smell and is typically delivered with a standard vaporizer, isoflurane has a pungent odor but does not require the special vaporizer, and nitrous oxide is a gas and does not use a liquid vaporizer.