Like many other academic institutions, Great Eastern University used the pain and distress categories identified in the USDA Annual Report to classify the level of pain or distress experienced by all animals in the school's biomedical research program, not just those species covered by the Animal Welfare Act and its regulations. Anesthesia induced by hypothermia was considered to be USDA category D (pain or distress alleviated by drugs). For years, the university had considered hypothermia an acceptable means of anesthesia for neonatal rats and mice less than one week of age. This technique was used to anesthetize pups prior to decapitation and for certain surgical procedures when inhalant or parenteral anesthetics were contraindicated by the research.

Over time, as the composition of the IACUC changed, so did attitudes toward using hypothermia. The issue was brought to a head when Jonathan Bellamy, a neuroscientist on the committee, questioned whether hypothermia should be considered a drug. He believed it was necessary to consider it a drug in order for animals subjected to hypothermia-induced anesthesia to be placed in category D; otherwise, he said, using the USDA's definition, animals anesthetized by hypothermia should be in category E (pain or distress unalleviated by drugs). The IACUC chairman, Larry Covelli, said that the argument was immaterial because use of the USDA categories was a convenience for the IACUC rather than a legal requirement. But Bellamy persisted. First, he said that the issue should be resolved because it could easily involve newborn hamsters or other species covered by the USDA. Second, he questioned whether hypothermia itself had a painful induction and recovery process, even if the committee assumed that there was satisfactory anesthesia at the endpoint. “Remember,” he said, “in humans, hypothermia is almost always used as an adjunct to general anesthesia, not as the sole means of anesthesia.” Finally, he said, he was not confident whether the hypothermic animal was paralyzed or anesthetized.

What do you and your IACUC think? Is hypothermia an acceptable means of anesthesia if other means cannot be used? If used, should it be considered category D or E?

Response to Protocol Review Scenario: The rodent species is immaterial

Response to Protocol Review Scenario: SOPs for hypothermia

Response to Protocol Review Scenario: Category definitions are limited