Louis,
I don't think that you are comparing the proverbial 'apples with apples'.
I think the main issue aboard aircraft is with various nav/comms systems, all of which receive e.m signals in order to process + provide information as their primary function. As such, it is more difficult to give them broad spectrum e.m immunity without reducing device sensitivity, and therefore adequate functionality. (Even if the aircraft is on the ground, a momentary signal of high field strength may be enough to de-sensitize a radio receiver so that the pilot misses/misinterprets a vital piece of info).
Nearly all medical devices on the other hand do not have such a need to use e.m. radiation as part of their inherent function, and should have a degree of e.m. immunity, as well as not being an emitter.
This CE requirement has become more stringent in recent years, and modern devices fairly immune (it is the antique, microprocessor based kit that is perhaps of most concern, since they were not built with e.m immunity in mind). Hopefully natural evolution will weed out thos most vulnerable (except if us biomeds manage to keep patching them up and sending them out again)
Can I respectfully deduce that you are an army bod, and not an RAF one?
this is because it MAY interfere with the electronic control systems, obviously somebody somewhere had enough evidence to obtain an 
