Blood is a graphic in all GTA games.
Blood in these versions are simple pixels and not very high detail.
GTA 3, Vice City, San Andreas
Blood was improved in these games having small (or large at times) pools of blood come from dead bodies (large), or from getting shot, attacked, etc. (spurts)
Blood has majorly improved in these versions by having blood on the protagonist and pools/spurts being more high definition, and in GTA V gunshots can rip holes in clothing where hit. Jumping out of vehicles make blood on the ground too. In GTA V, after coming out of a hospital from being Wasted, the player will still have blood on some spots of his body and/or face.