If a pt has a high inr (2.1 & 2.2) but is not on coumadin (warfarin) should a work up be done to determine the cause? why? what would a work up consist of?

Absolutely: High INR indicates impaired blood clotting. It can be caused by advanced liver disease, severe infections, certain types of cancer, very large blood loss, and severe malnutrition. It definitely needs to be investigated if the cause is not obvious.

High INR: Usual cause is hepatic failure/insufficiency as elevated INR reflects vit K dependent clotting. Sepsis and DIC will sometimes cause INR to become elevated but generally thats clinically obvious. Certain antibiotics can cause elevated INR with coumadin/warfarin use. I would review the patient's medications to make sure they aren't taking coumadin/warfarin and then check liver functions.