A patient is stabilized on warfarin with an international normalized ratio (INR)of 2.7.He develops pneumonia and is admitted to the hospital.His appetite is depressed and he is placed on broad-spectrum antibiotic agents.At 1 week after the admission,his INR is 5.0.What is the most likely interpretation?

Question

Quizplus · Accepted Answer

This elevated INR is probably the result of a deficiency of vitamin K,which increases the effects of warfarin.Vitamin K deficiency is seen during use of broad-spectrum antibiotic agents that destroy gut flora and in people with a poor diet,both of which are present in this patient.

A Patient Is Stabilized on Warfarin with an International Normalized