Summary

Aim: To compare clinical outcomes in a randomised comparison oftreatment with danaparoid sodium (a heparinoid), or dextran 70, forheparin-induced thrombocytopaenia (HIT) plus thrombosis. Methods:Forty-two patients with recent thrombosis and a clinical diagnosis ofprobable HIT who presented at ten Australian hospitals during a studyperiod of six and one half years were randomly assigned to open-labeltreatment with intravenous danaparoid or dextran 70, each combinedwith oral warfarin. Thirty-four patients (83%) had a positive plateletaggregation or 14C-serotonin release test for HIT antibody. Twenty-fivereceived danaparoid as a bolus injection of 2400 anti-Xa units followedby 400 units per hour for 2 h, 300 units per hour for 2 h, and then200 units per hour for five days. Seventeen received 1000 mL dextran70 on day one and then 500 mL on days 2-5. Patients were revieweddaily for clinical evidence of thrombus progression or resolution, freshthrombosis or embolism, bleeding or other complications. The primarytrial endpoint was the proportion of thromboembolic events with completeclinical resolution by the time of discharge from hospital. Results:With danaparoid, there was complete clinical recovery from 56% ofthromboembolic events compared to 14% after dextran 70 (Odds Ratio10.53, 95% Confidence Interval 1.6-71.4; p = 0.02). Clinical recoverywith danaparoid was complete or partial in 86% of thromboembolicevents compared with 53% after dextran 70 (Odds Ratio 4.55, 95%Confidence Interval 1.2-16.7; p = 0.03). Overall clinical effectivenessof danaparoid was rated as high or moderate in 88% of patients comparedwith 47% for dextran 70 (p = 0.01). One patient given danaparoiddied of thrombosis compared with three patients given dextran 70.The platelet count returned to normal after a mean of 6.7 days withdanaparoid and 7.3 days with dextran 70. There was no major bleeding with either treatment. Conclusion: danaparoid plus warfarin treatmentfor HIT with thrombosis is effective, safe, and superior to dextran 70plus warfarin.