In the former case, the resources of medical centers, hospitals and their associated facilities will mostly remain intact - if not in your town, then someplace fairly close.
In one of the latter worst cases, you might be on your own for medical treatment, at least for some period of time.
A useful tool to have available on a thumb drive or an "SD card" and kept in your EMP safe container (see here) is the Special Operations Forces Medical Handbook available in pdf format.
Special Operations Forces Medical Handbook, 2001, is the first edition of a comprehensive medical reference resource designed for Special Operations Forces (SOF) medics. This “single-source” reference provides many revolutionary approaches to accessing medical information, such as a treatment hierarchy based on available medical resources and mission circumstances commonly facing the SOF Medic. The Special Operations Forces Medical Handbook is an innovative achievement in military medical knowledge, with contributions by over 80 medical specialists organized into a problem-oriented template for reference to diagnoses and treatmentsYou could even print it out if you are a "belt and suspenders" type though it does run 723 pages. The pdf has a nice index and the pictures are, in some cases, colorful. The issue above is from 2001. Amazon offers a paperback version updated through 2008 here for about $16 new. Used versions are cheaper.
Probably won't ever need it, but . . . it would be really nice to have after one of those worst case things.