Biomedical engineers rarely work in hospitals, unless they are doing research or are involved in clinical trials. Generally, they design and develop medical devices, materials and instrumentation.
Here is the Biomedical Engineering Society’s webpage and description of what a BME does.
http://www.bmes.org/careers.asp
Thanks for asking.
BTW, Duke’s BME department is #2 in the USA behind Johns Hopkins. My son pulled his application to Duke when Nifong refuse to drop all of the charges after Crystal Gail Magnum recanted on the rape charge.