How can I learn to maintain and repair the high tech hospital equipment? any resources?

first>> read the  information about any medical machine , undestand   the  digram, service and data sheet>secand>> when you make any maintain be sure how the machine work< know about electric for example how measuring any electronic board

u can do this by knownig the basic theory for each equipment and the tech is differ from one equipment to another  u can read ther service & user manual for each equipment to repair it

You should do internship or service and maintenance training in some reputed medical company dealing in high tech medical equipments and gain an experience of at least2-3 years.