Forgotten source of heparin as a cause of worsening platelet count in a pre-existing heparin induced thrombocytopenia

Heparin induced thrombocytopenia is a known complication of using heparin. In this case, the patient developed deep vein thrombosis while he was in the ICU. Upon administration of heparin, he developed thrombocytopenia. After stopping heparin and using alternative anticoagulation, there was no improvement in the platelet count, however. Eventually, there was another source of heparin that could contribute to the worsening of platelet function