I've tried various google phrases like "predators scent of blood," "predators fresh blood," etc. and I'm out of ideas. And I've been reading up on tiger hunting techniques (here; Wiki). They use their sense of smell to sniff out prey, but I haven't found the specifics of what they might sniff for.
The setting is a pre-modern (but clean) urban area which the tiger is stuck in, and she's hungry. Will she go for the bleeding guy first?