This stuff is out there.
This caught my attention ——”buildup of fluid in the lungs”
https://www.livescience.com/15899-drinking-blood-safe.html
Excerpt
Because blood is so rich in iron — and because the body has difficulty excreting excess iron — any animal that consumes blood regularly runs a risk of iron overdose. While iron is necessary for all animals (and indeed most life), in high doses it can be toxic. This condition, called haemochromatosis, can cause a wide variety of diseases and problems, including liver damage, buildup of fluid in the lungs, dehydration, low blood pressure, and nervous disorders.
Never eat the liver of a predator.