Heparin-induced thrombocytopenia without thrombosis: an evidence-based review of current literature
ABSTRACT
Background and aim: There has been a recent change inthe management guidelines for patients with heparin-inducedthrombocytopenia with the addition of arecommendation to commence parenteral anticoagulationin patients with isolated HIT without evidence ofthrombosis. We assessed the evidence supporting thisrecommendation, to answer the following questions: in apatient with isolated HIT, should alternative anticoagulationbe commenced, what alternative agent should be used,what is the recommended duration of anticoagulation, andwhen should warfarin be used?
Methods: We searched MEDLINE (using keywords“heparin-induced thrombocytopenia”, “heparin inducedthrombocytopaenia”, “HIT” and “HITTS”) and PubMed(using MeSH terms “thrombocytopenia” and “heparin”)from 1966 to 2006 and selected articles for furtherassessment according to specified criteria.
Results: We assessed 12 non-randomised studies, five large case series and multiple small case series.
Conclusion: Although patients with isolated HIT are atconsiderable risk of new thrombosis, there is limitedevidence to support or reject the use of non-heparinanticoagulation in this group. Non-randomised, historicallycontrolled trials support the use of lepirudin andargatroban; evidence favouring danaparoid is limited tolarge case series and one retrospective observational study.Duration of parenteral anticoagulation and warfarin use areguided by consensus opinion alone.
Crit Care Resusc 2006; 8: 345-352
