In patients with vascular diseases, heparinization is necessary for surgery. Here, we report the case of a 77-year-old man who presented with heparin-induced thrombocytopenia (HIT) during the postoperative management of tongue cancer. The patient was already on warfarin owing to arteriosclerosis obliterans, and was perioperatively administered heparin by a cardiologist. The prothrombin time-international normalized ratio (PT-INR) was stabilized, and heparin administration was terminated on postoperative day 23. However, on postoperative day 41, the PT-INR was prolonged; warfarin was discontinued, and heparin was re-administered. On day 6 after heparin re-administration (postoperative day 47), the patient developed sudden fever. Contrast-enhanced computed tomography (CT) imaging was performed to evaluate the fever and showed a thrombus at the L5 level of the inferior vena cava. Blood examination showed a platelet count of 108,000 /μL; however, the next day, the count was 87,000 /μL. On day 10 after heparin re-administration (postoperative day 51), contrast-enhanced CT imaging showed an increase in thrombus formation. Therefore, inferior vena cava filter insertion surgery was performed on day 13 of heparin re-administration (postoperative day 54). The patient was diagnosed with HIT because of thrombocytopenia and increased thrombin after the re-administration of heparin, which was discontinued on postoperative day 64; argatroban (an anti-thrombin drug) was administered for HIT treatment. The patient was discharged with an indwelling inferior vena cava filter and intestinal fistula.
