I thought it was ridiculous that he was practically a backup the Doctor. Who are they kidding? Tom Paris performing a life-saving operation, please. They should have replaced Kes with a advanced holographic nurse/medic, not dump Paris in sick bay because he had so little to do at the helm.
As I understood it, field medics are basically equal to an EMT.
I don't believe they're trained or skilled in surgery.
If Tom or Kes were skilled at surgery, then we never would of had the dilemma the EMH had in "Latent Image" due to there being only him with the knowledge and ability to perform surgery.