PF803 VON WILLEBRAND FACTOR DELAYS LIVER REPAIR AFTER ACETAMINOPHEN-INDUCED ACUTE LIVER INJURY IN MICE
Authors: D. Groeneveld, H. Cline-Fedewa, K. Baker, K.J. Williams, R.A. Roth, K. Mittermeier, T. Lisman, J.S. Palumbo, J.P. Luyendyk
Journal: HemaSphere (2019)

Background: Management of venous thromboembolism (VTE) in patients with haematological malignancies (HM) and thrombocytopenia challenges clinicians because this scenario is encumbered with several risks. Our panel, composed by elected members of the Gruppo Italiano Malattie EMatologiche dell’Adulto (GIMEMA) Working Party on Thrombosis and Haemostasis (WPHT). has recently published a consensus,reached by RAND method, focused on the platelet cut-off for safely administering Low Molecular Weight Heparin (LMWH) in adult patients with hematological malignancies, acute (no later than 1 month) or non-acute VTE and thrombocytopenia (PLT< 100 × 109/L). Aims: Aim of the current study was to produce a formal consensus, not achieved by the previous method, focused on anticoagulant treatment with LMWH in adult patients with HM affected by acute or non-acute catheter-related VTE and severe thrombocytopenia Methods: Delphi methodology was adopted to allow members of the GIMEMA-WPHT to achieve consensus on the above reported issue, starting from available scientific data. For each indication, the panel members (N = 21, 3 validators and 18 participants) rated the benefit-to-harm ratio of the indication on a scale of 1 to 5, where 1 means that the expected harms greatly outweigh the expected benefits, and 5 means that the expected benefits greatly outweigh the expected harms. The first survey consisted of 7 different statement; after analysis of the first results, it was decided to discuss and re-formulate 3 items, panel members were then asked to rate again items for which no consensus had been achieved. The interventions considered were the administration of different doses of LMWH (therapeutic, reduced dose at 50% of full therapeutic dose, prophylactic dose) and PLT transfusions, according to platelet counts >30 <50 × 109/L, in patients with catheter-related VTE. LMWH doses were defined according to the datasheet for each LMWH molecule. Results: After the first round, an agreement >80%was reached for 4 out of the initial 7 items. Three items were thus reformulated nd partecipants were asked to reasses them After the second round, an agreement was reached for all items. The panel of experts expressed the following consensus: for the management of acute-catether related VTE with platelet counts >30 <50 × 109/L in patients with HM, anticoagulant treatment with reduced dose to 50% of LMWH is appropriate (90%agreement); for the management of non-acute catheter-related VTE, treatment with reduced dose to 50% of LMWH is also appropiate. PLTs transfusions were deemed inappropriate in both,acute (90% agreement) and non-acute (100% agreement) catheter-related VTE. The administration of prophylactic dose of LMWH was deemed inappropriate with an agreement of 90% in patients with acute catheter-related VTE and 80% in subjects with non-acute catheter-related VTE. Summary/Conclusion: Delphi method has allowed to reach consensus on a still debated issue, where scientific evidences are lacking.GIMEMA-WPHT suggests anticoagulant treatment with reduced dose to 50% of LMWH for platelet counts >30 <50 × 109/L in patients with haematological malignancies and either acute or non-acute catheter-related VTE.