Portal vein thrombosis after total knee replacement: a case report.

We present a 74-year-old woman who developed a portal vein thrombosis following an elective total knee replacement. She had atrial fibrillation for which she was taking warfarin for anticoagulation. Seven days prior to surgery, she was instructed to discontinue warfarin and replace it with prophylactic low-molecular-weight heparin. On postoperative day 1, routine blood tests revealed deranged hepatic synthetic function, despite standard anticoagulation management. Doppler ultrasonography confirmed a portal vein thrombosis. She was treated with therapeutic doses of low-molecular-weight heparin until her international normalised ratio reached therapeutic levels. Her liver function results had normalised 2 weeks later. Portal vein thrombosis is a potentially fatal complication that is reversible if identified and treated early.