Mehdi Oualha1,2, Christophe Chardot3, Dominique Debray4, Fabrice Lesage1, Annie Harroche5, Sylvain Renolleau1, Jean-Marc Treluyer1,2, Saïk Urien2. 1. Service de réanimation et surveillance continue médico-chirurgicales, Hôpital Necker Enfants-Malades, Université Paris Descartes, Sorbonne-Paris Cité, 149 rue de Sèvres, 75015, Paris, France. 2. EA7323, Evaluation des thérapeutiques et pharmacologie périnatale et pédiatrique, Université Paris Descartes, Paris, France. 3. Service de chirurgie viscérale pédiatrique, Hôpital Necker Enfants-Malades, Université Paris Descartes, Sorbonne-Paris Cité, 149 rue de Sèvres, 75015, Paris, France. 4. Unité d'hépatologie pédiatrique, Hôpital Necker Enfants-Malades, Université Paris Descartes, Sorbonne-Paris Cité, 149 rue de Sèvres, 75015, Paris, France. 5. Service d'hématologie clinique, Hôpital Necker Enfants-Malades, Université Paris Descartes, Sorbonne-Paris Cité, 149 rue de Sèvres, 75015, Paris, France.
Abstract
AIMS: Preventing post-liver transplantation (LT) hepatic artery and portal vein thrombosis includes enoxaparin administration. Enoxaparin pharmacokinetics (PK) has not been investigated in children following LT. We described an enoxaparin PK model in 22 children the first week following LT. METHODS: Anti-Xa activity time-courses were analysed using a nonlinear mixed effects approach with Monolix version 2016R. RESULTS: Anti-Xa activity time-courses were well described by a one-compartment model with first order absorption and elimination. Bodyweight prior to surgery (BWPREOP ) and the related postoperative variation (BW(t)) were the main covariates explaining CL and V between subject variabilities. Parameter estimates were CLi = CLTYP * (BWPREOP /70)3/4 ; Vi = VTYP * (BW(t)/70)1 ; where typical clearance (CLTYP ) and typical volume of distribution (VTYP ) were 1.23 l h-1 and 14.6 l, respectively. Standard dosing regimens of 50 IU kg-1 12 h-1 were insufficient to reach the target range of anti-Xa activity of 0.2-0.4 IU ml-1 . Specifically, seven children (32%) never attained the target range during the whole period of treatment and all children were at least once underdosed. According to the final results, we simulated individualized dosing regimens within 4 h following the first administration. More than 100 IU kg-1 12 h-1 are suggested to reach the target range of anti-Xa activity of 0.2-0.4 IU ml-1 from the first day. CONCLUSION: Thanks to this model, the initial and maintenance doses could be assessed to rapidly achieve the target range. Higher doses per kg, especially in the youngest children, are suggested.
AIMS: Preventing post-liver transplantation (LT) hepatic artery and portal vein thrombosis includes enoxaparin administration. Enoxaparin pharmacokinetics (PK) has not been investigated in children following LT. We described an enoxaparin PK model in 22 children the first week following LT. METHODS: Anti-Xa activity time-courses were analysed using a nonlinear mixed effects approach with Monolix version 2016R. RESULTS: Anti-Xa activity time-courses were well described by a one-compartment model with first order absorption and elimination. Bodyweight prior to surgery (BWPREOP ) and the related postoperative variation (BW(t)) were the main covariates explaining CL and V between subject variabilities. Parameter estimates were CLi = CLTYP * (BWPREOP /70)3/4 ; Vi = VTYP * (BW(t)/70)1 ; where typical clearance (CLTYP ) and typical volume of distribution (VTYP ) were 1.23 l h-1 and 14.6 l, respectively. Standard dosing regimens of 50 IU kg-1 12 h-1 were insufficient to reach the target range of anti-Xa activity of 0.2-0.4 IU ml-1 . Specifically, seven children (32%) never attained the target range during the whole period of treatment and all children were at least once underdosed. According to the final results, we simulated individualized dosing regimens within 4 h following the first administration. More than 100 IU kg-1 12 h-1 are suggested to reach the target range of anti-Xa activity of 0.2-0.4 IU ml-1 from the first day. CONCLUSION: Thanks to this model, the initial and maintenance doses could be assessed to rapidly achieve the target range. Higher doses per kg, especially in the youngest children, are suggested.
Authors: Vatche G Agopian; Henrik Petrowsky; Fady M Kaldas; Ali Zarrinpar; Douglas G Farmer; Hasan Yersiz; Curtis Holt; Michael Harlander-Locke; Johnny C Hong; Abbas R Rana; Robert Venick; Sue V McDiarmid; Leonard I Goldstein; Francisco Durazo; Sammy Saab; Steven Han; Victor Xia; Jonathan R Hiatt; Ronald W Busuttil Journal: Ann Surg Date: 2013-09 Impact factor: 12.969
Authors: Paul Monagle; Anthony K C Chan; Neil A Goldenberg; Rebecca N Ichord; Janna M Journeycake; Ulrike Nowak-Göttl; Sara K Vesely Journal: Chest Date: 2012-02 Impact factor: 9.410
Authors: Simon D Harding; Joanna L Sharman; Elena Faccenda; Chris Southan; Adam J Pawson; Sam Ireland; Alasdair J G Gray; Liam Bruce; Stephen P H Alexander; Stephen Anderton; Clare Bryant; Anthony P Davenport; Christian Doerig; Doriano Fabbro; Francesca Levi-Schaffer; Michael Spedding; Jamie A Davies Journal: Nucleic Acids Res Date: 2018-01-04 Impact factor: 16.971