title: Anticoagulant properties of enoxaparin 400 IU/mL-40 % ethanol catheter lock solution.
abstract: Unfractionated heparin (UFH) is the most widely used interdialytic lock solution but has no anti-infectious properties. Ethanol at a content ≥40 %v/v eradicates experimental biofilm but has no anticoagulant properties. In contrast to UFH, enoxaparin (Enox) can be combined with 40 % ethanol without precipitation. Enoxaparin 400 UI/mL-40 % ethanol (Enox/Eth) has antibiofilm properties and therefore has promise as an alternative lock solution. This study assessed the anticoagulant properties of Enox/Eth. Enox and Enox/Eth were diluted in whole blood at a final Enox concentration of 0.5, 1 (N = 6 samples), 1.5 (N = 4) and 2 (N = 6) IU/mL. Anti-Xa activity was determined by chromogenic assay and the inhibition of endogenous thrombin potential (ETP) by thrombinography. Quantitative data were compared by the Mann-Withney U test. For Enox concentrations of 0.5, 1, 1.5 and 2 UI/mL in whole blood samples, the mean ± SD values of the anti-Xa activity were 0.68 ± 0.09, 1.26 ± 0.14, 1.73 ± 0.30, 2.35 ± 0.32 UI/mL for Enox/Eth and 0.94 ± 0.15, 1.80 ± 0.22, 2.74 ± 0.23, 3.54 ± 0.44 UI/mL for Enox (P = 0.03, P = 0.03, P = 0.13, P = 0.03); and of the percentage of ETP inhibition was 17.36 ± 9.65, 30.27 ± 17.06, 36.5 ± 17.06, 57.82 ± 15.42 for Enox/Eth, and 42.96 ± 15.68, 68.93 ± 10.01, 83.5 ± 8.81, 91.19 ± 4.67 for Enox (P = 0.03, P = 0.03, P = 0.13, P = 0.03), respectively. The median and IQR values of Enox concentration inhibiting 50 % of ETP (IC50 ETP) were 1.8 [1.1-2.4] IU/mL for Enox/Eth and 0.7 [0.3-0.9] IU/mL for Enox, P = 0.03. Enox/Eth has strong anticoagulant activity, albeit lower than that of Enox, but with an extremely low IC50 ETP compared to the Enox concentration of non-diluted Enox/Eth.
authors.affiliation: Service de Réanimation Médicale Polyvalente CHU de Clermont-Ferrand, Clermont-Ferrand, France.
authors.forename: Laure
authors.initials: L
authors.lastname: Calvet
authors.affiliation: Université de Lyon, 42023 Saint-Etienne, France ; Groupe de Recherche sur la Thrombose, EA 3065, 42023 Saint-Etienne, France.
authors.forename: Michèle
authors.initials: M
authors.lastname: Piot
authors.affiliation: Laboratoire Chimie Analytique et Spectrométrie de masse UMR 990 Inserm-UdA, Clermont-Ferrand, France.
authors.forename: Claire
authors.initials: C
authors.lastname: Lartigue
authors.affiliation: Service de Réanimation Médicale Polyvalente CHU de Clermont-Ferrand, Clermont-Ferrand, France ; Laboratoire Microorganismes: Génome Environnement (LMGE), Clermont Université, UMR CNRS 6023, Université d'Auvergne, Clermont-Ferrand, France ; Hôpital Gabriel Montpied, Service de Réanimation Médicale Polyvalente, CHU de Clermont-Ferrand, 63003 Clermont-Ferrand Cedex 01, France.
authors.forename: Bertrand
authors.initials: B
authors.lastname: Souweine
authors.affiliation: Université de Lyon, 42023 Saint-Etienne, France ; Groupe de Recherche sur la Thrombose, EA 3065, 42023 Saint-Etienne, France ; Laboratoire d'Hématologie, CHU Saint-Etienne, Hôpital Nord, 42055 Saint-Etienne, France.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Tardy-Poncet
keywords: Antithrombotic effect; Catheter lock; Enoxaparin; Ethanol; Lock solution; Thrombin generation