The Big Sleep: How Do You Anesthetize a Hippopotamus?

ScienceDaily (July 3, 2012) — It may rank fairly low in most lists of pressing problems to be solved but an increasing number of zoos and wildlife collections as well as gamekeepers nevertheless need to come up with an answer: How do you anesthetize a hippopotamus? Difficulties are posed not only by the undesirability of approaching waking animals but also by hippos' unique skin morphology and by the animals' sensitivity to standard anesthetic methods. 

A new procedure is now described by the group of Chris Walzer at the Research Institute of Wildlife Ecology of the University of Veterinary Medicine, Vienna and published in the current issue of theJournal of the American Veterinary Medical Association.

All zoo animals -- and sometimes also wild animals -- occasionally need veterinary treatment and anesthesia is clearly required in many cases. For most animals the procedures are well established but for a variety of reasons it has proven difficulty to anaesthetize hippopotamuses. The thick skin and the dense subcutaneous tissue make it difficult to introduce sufficient amounts of anesthetics and opioid-based anesthetics often cause breathing irregularities and occasionally even death. In addition, the level of anesthesia is only rarely sufficient to enable surgery to be undertaken: few vets wish to be around when a drugged hippopotamus starts to wake up.

Continued:  http://www.sciencedaily.com/releases/2012/07/120703120622.htm