Laboratory Animals and Anesthetics Quiz

Acceptable Methods for Anesthesia in Small Laboratory Rodents

• Inhaled anesthesia is a common and acceptable method for anesthetizing small rodents in laboratory settings.
  • Isoflurane is a commonly used inhalant anesthetic in mice and rats.
  • Sevoflurane is another suitable inhalant anesthetic.
  • Carbon dioxide (CO2) can be used as an euthanasia method, but only under strict conditions.
  • CO2 is not recommended as an anesthetic for routine surgical procedures due to potential complications.

Conditions for Using CO2 as an Inhaled Anesthetic

• CO2 can be used as an inhaled anesthetic in small rodents only if the aim is to induce euthanasia, not anesthesia.
• The concentration of CO2 used for euthanasia must be high enough to quickly induce unconsciousness and death.
  • This is because high concentrations of CO2 can cause stress and discomfort in the animal.
  • Using an unsuitable concentration of CO2 can lead to pain and distress, so care must be taken to ensure the appropriate concentration is used.

Acceptable Physical Anesthesia

• Physical anesthesia is another acceptable method for anesthetizing small laboratory rodents.
• This method involves cooling the animal down to lower body temperature but not freezing, which induces a state of torpor.
• Torpor is a state of reduced metabolic activity and lowered body temperature.
• This method is often used for specific procedures where inhalant anesthesia is not suitable, such as for imaging studies.

Unacceptable Methods of Anesthesia

• Methods that are not acceptable for anesthetizing small laboratory rodents include:
  • Physical methods that induce pain or distress to the animal, such as using a tight restraint or crushing the animal.
  • Chemicals that are not proven to be effective or safe for the species being used.
  • Procedures that cause prolonged pain or suffering.
  • Any method that does not induce a state of unconsciousness and analgesia.
• It is crucial to use ethical and humane methods of anesthesia to minimize pain and discomfort to the animal.