Platelet transfusion and catheter insertion for plasma exchange in patients with thrombotic thrombocytopenic purpura and a low platelet count.

BACKGROUND: In thrombotic thrombocytopenic purpura (TTP), platelet (PLT) transfusion is contraindicated unless a life-threatening hemorrhage occurs. However, when PLT count is low (<20 × 10(9) /L), their benefit-risk balance before central venous catheter (CVC) insertion for plasma exchange (PE) has not specifically been addressed in guidelines. CASE REPORTS: We report two cases in which PLTs were transfused before CVC insertion for PE, resulting in fatal myocardial infarction or neurologic complications. DISCUSSION: To date, there is a paucity of high-quality, evidence-based information on prophylactic PLT transfusion for CVC placement in TTP. Several monocenter series report that CVC could be inserted safely without PLT transfusion by experienced teams under ultrasound guidance. Uncertainty makes most physicians uncomfortable with this decision and this is a common reason why PLT transfusion remains a "precautionary" albeit misguided position. CONCLUSION: We propose a practical algorithm to avoid unnecessary PLT transfusion before CVC insertion for rapid PE in the initial management of TTP patients. We recommend no prophylactic PLT transfusion but CVC insertion in a compressible vein under ultrasound guidance by an experienced team or quick PE started on two peripheral veins if possible. PLTs should only be transfused in case of severe bleeding in association with plasma infusion and CVC insertion for immediate PE.