I would think it depends on the type of contamination and what the end use of the device is.  For an external unit I would determine which parts are not tolerant and then decide if the parts are worth trying to re-use.  If you are talking just the plastic parts then there are number of good sanitizer fluids on the commercial market that should work.  If the unit is an implantable then the final unit when ready for resale or reuse would have to be resterilized anyway.  

I worked for a company that took a feeding device and reconditioned them.  We were lucky and most of the parts that we kept were the plastic molded pieces and we used a spray sanitizer on those pieces.  The circuit assembly only had a few parts that weren't tolerable of cleaning and sanitizing.  We built extra units with new production runs (kept costs down that way in a servicing enviroment) and then threw the bad ones out.  We found all kinds of unbelievable stuff in these units.  Some I will never forget (absolutely gross).  

Contact me off line if you want to discuss further.