Use of Heparin during Cardiopulmonary Bypass in Patients with a History of Heparin-Induced Thrombocytopenia

Abstract

Patients with heparin-induced thrombocytopenia are at high risk for thromboembolic complications. Heparin-induced thrombocytopenia is caused by heparin-related and platelet-activating antibodies.¹ These antibodies, referred to as HIT antibodies, are usually undetectable 100 days after the cessation of heparin therapy.² Avoidance of a secondary immune response and the use of alternative anticoagulants are strongly recommended in patients who have had heparin-induced thrombocytopenia to avoid another bout. If such patients require cardiopulmonary bypass, danaparoid and hirudin are available.^3,4 Both treatments, however, carry the risk of potentially life-threatening hemorrhage, because their anticoagulant actions cannot be neutralized at the end of cardiopulmonary bypass. In addition, both agents require specialized intraoperative monitoring methods, which are not widely available.