While I find adrenaline cool in theory, your suggested conditions for adrenaline feel very arbitrary. Admittedly, a lot of game’s have mechanics with otherwise arbitrary conditions, but I don’t feel like this adds anything.
I don’t think it’s giving the player an interesting/fun solution to a problem, it’s just forcing them to be a little bit better. Doesn’t really seem like a fun mechanic, and it doesn’t feel like the player really deserves it either.
I do appreciate trying to rework the medical item though, since it (and Morphine) are currently rather garbage.
If I was to suggest something like this I’d probably do two things with it:
- Introduce a “sanity” mechanic, and make adrenaline a minor part of it
- Make the adrenaline item give more physical boosts to the player (like you’ve implied)