Usefulness of Danaparoid sodium in patients with Heparin-induced thrombocytopenia after cardiac surgery

OBJECTIVE: Thrombocytopenia is a common problem in cardiovascular surgery patients. However, heparin-induced thrombocytopenia (HIT) is a rare but life-threatening complication of prophylaxis or treatment with heparin. Prompt management of HIT with an alternative anticoagulant is necessary due to the extreme risk of thrombotic complications. Therefore, we evaluated the effects of danaparoid in the treatment of HIT in patients with cardiac surgery who are at moderate to high risk of HIT. METHODS: A prospective observational study involving 418 postcardiac surgery patients who received unfractionated heparin and low-molecular weight heparin was conducted in an educational tertiary cardiac care hospital in Iran. All patients were assessed for HIT type II based on thrombocytopenia and pretest clinical scoring system, the "4T's" score. HIT patients were treated with 1500-2500 units intravenous bolus danaparoid sodium followed by 200-400 units/h for a mean of 5 days. Successful response to danaparoid therapy, defined as augmentation in platelet count and improvement of thrombotic events was assessed in all patients treated with danaparoid. FINDINGS: According to pretest clinical score (4T's), the probability of HIT was high in 14 (3.3%) patients and intermediate in three ones (0.7%). 15 patients with HIT were treated with danaparoid. One death occurred in danaparoid-treated group due to persistent thrombocytopenia. The rest of patients were treated successfully with danaparoid without any major thrombotic complication. CONCLUSION: According to our data and the previous studies', HIT can be managed prosperously with danaparoid in postcardiac surgery patients. However, with the absence of any increase in platelet count after 3-5 days of danaparoid therapy and/or the occurrence of a new thrombotic event, danaparoid cross-reactivity with heparin should be suspected.