Medical coding is a very separate animal from EMS. I know this because I am a paramedic and my fiancée is a medical coder. Medical coders are usually separated from practitioners, so that there is no conflict of interest between best treatment vs expense of treatment.
It pays way more than EMS does. You can typically make $16-20/hr starting with a two year degree, and double that within a few years...and double that if you manage a department a few years later.
If you already have a bachelor's degree, or do not plan on getting a master's in the field (to move into management), then get an associate's degree...it is much, much, much cheaper. You could always finish a bachelor's later if you choose to do so. If you plan to go straight through to grad school to move up the pipeline IMO management as soon as possible, then get a bachelor's first.
My fiancée took the associates (but already had a bachelor's) degree from Columbus State Community College. It was an all online program and she finished in about 1 year (because she had a bachelor's already). Her friend had nothing, and finished in a year and a half.
It is not at all connected with EMS. It will not help you as an EMT (aside from the biology and anatomy and pharmacology courses) and being an EMT will not help you as a coder.