Allow blood packs to directly increase a patient's blood level.

[PHLiao]

Currently writing this as I've been somewhat confused on why this doesn't appear to be the case for a while. I'd rather like it if blood IVs, instead of going into a person's bloodstream as a chemical that's as effective as if a person swallowed a pill of blood, why not instead have blood IVs directly increase a person's blood level? It doesn't have to be a pure 1:1 ratio if that's too strong, but it would give more of a reason to use blood IVs when people have lost most of their blood.