Prolog: The current Medical System is kinda nice and complex like you need certain stuff to do stuff but i think its only scratch the surface of a potential Medic system. I used to play Arma 3 and there are a loot of good approaches. I used the Ace Medical + KAT advanced Medical as my inspirations, to show case i will use some images from Arma 3 to show you how things could be done. This idea will do the medic system more complex but also more intuitive.
Under Medic you will see ur body like in the picture.. If you click on a body part it will showcase you which kind of injuries do u have (for example scratches, deep wounded scratches.. shrapnels or bullets, deep wounds like bites, traumas, broken bones etc.
On the right you got also general informations like how much blood do you got (will be the new HP bar), your body tempature, Bloodpressure, Pain. With certain items or after treating you got more in depth informations like how good is ur pulse, bloodpressure, Ilnesses etc.
Bandages: Quicklot/Pflaster closing down minor scratches and will open not often again.
Elastic Bandage: Will closing down big wounds the chance of reopening will be high
Compression Bandages: Will be the middle between both.. you need more to close bigger wounds but the chance of reopen will be lower than elastic.
Makeshift: will clothes Minor deep wounds too like Compression but have a higher chance of reopening wounds.
Stethoscope: Can be used to hear the lunge and heart too, to identify lunge and heart disfunctions.