A 60-year-old woman with a pancreatic mass is scheduled to undergo a non-emergency endoscopic procedure. She has a past medical history of stroke and has been on warfarin for the past 20 years. Pre-surgical lab values include an international normalized ratio (INR) of 10.0 (reference range: 0.8 to 1.2). She is not currently bleeding. The patient was given 5 mg of oral vitamin K; her INR was rechecked approximately five hours later and found to be 12.3.
Heidi Lehrke, D.O.
Resident, Anatomic and Clinical Pathology Residency
Justin Kreuter, M.D.
Consultant, Division Transfusion Medicine
Instructor in Laboratory Medicine and Pathology,
Mayo Clinic College of Medicine