Thrombocytopenia in two patients treated with low-dose heparin.

Two cases of thrombocytopenia, one resulting in bleeding, are reported in patients treated with prophylactic low-dose heparin. The evidence indicates that low-dose heparin was responsible. A review of the literature indicates that heparin-induced thrombocytopenia may be a common event. Since low-dose heparin has been shown to decrease the incidence of venous thrombosis and subsequent pulmonary embolism in patients undergoing major surgery, recommendations are made for monitoring platelet counts in such patients.