Upvote:-1
There's a partial answer there on the history section and modern day section:
There's more in depth info here:
Hopefully both of those links will complete each other.
Let me know if you need me to expand.
Upvote:1
For combat forces there was a regimental medical department that had personnel ranging from Doctors to stretcher-bearers. A good outline of the evolution of them is here.
The airborne medicos were in fact airborne trained and there is an outline of their organization and operational history at another page on the site.
In the PTO the Marines had aid from Navy Hospital Corpsman. It seems that most trained with the marines and had a fair amount of medical knowledge since they spent time in hospitals. Here's a training guide.
Note that some corpsmen with the same ratings even did surgeries in submarines in emergency cases.