Which anesthesia is generally superior for mice undergoing major surgical procedures?

• A. Oral sedation
• B. Inhalation anesthesia
• C. Intramuscular anesthesia
• D. Topical anesthesia

Answer: (B)

For major surgery in mice, the ability to precisely control the depth of anesthesia with rapid onset and recovery is essential. Inhalation anesthesia using volatile agents like isoflurane or sevoflurane provides that control: you can steadily deepen or lighten the anesthetic plane during a long procedure by adjusting the vaporizer setting, and once you stop delivering the gas, the animal wakes quickly because the agent is eliminated through the lungs. This predictable titration and quick recovery are especially valuable in small, fast-metabolizing animals where conditions change and close monitoring is needed throughout the operation. Inhalants also tend to have a wide safety margin when used with proper equipment and monitoring, reducing the risk of prolonged depression of respiration and circulation compared with some injectable regimens. Other options either don’t provide reliable depth for surgery (oral sedation), offer poor titration and unpredictable duration (intramuscular), or don’t reach true surgical anesthesia for deeper tissue procedures (topical). So, inhalation anesthesia is generally the best choice for major mouse surgeries.