title: Ex vivo evaluation of 4 different viscoelastic assays for detecting moderate to severe coagulopathy during liver transplantation.
abstract: Prolonged prothrombin time (PT) and its ratio are routinely used for the assessment of candidates for liver transplantation (LT), but intraoperative coagulation management of transfusion is hindered by its long turnaround time. Abnormal reaction time (R time) on thromboelastography (TEG) or clotting time (CT) of rotational thromboelastometry (ROTEM) are presumably an alternative, but there is a paucity of clinical data on abnormal R time/CT values compared to PT during LT. After receiving institutional review board approval and informed consent, we obtained blood samples from 36 LT patients for international normalized ratio (INR), factor (F) X level, and viscoelastic tests (EXTEM/INTEM and kaolin/rapid TEG) at baseline and 30 minutes after graft reperfusion. Receiver operating characteristic (ROC) curves were calculated for INR > 1.5 and viscoelastic R time/CT thresholds to assess the ability to diagnose FX deficiency at the moderate (<50%) or severe (<35%) level. The FX deficiency data were calculated using cutoff values of INR (>1.5) and abnormal R time/CT for TEG and ROTEM. Tissue factor (TF)-activated INR and EXTEM-CT performed well in diagnosing FX below 50%, but rapid TEG with combined TF and kaolin activators failed. Improved performance of INTEM-CT in diagnosing FX below 35% underlies multifactorial deficiency involving both intrinsic and common pathways. In conclusion, the differences among different viscoelastic tests and clinical situations should be carefully considered when they are used to guide transfusion during LT.
authors.affiliation: Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Ezeldeen
authors.initials: E
authors.lastname: Abuelkasem
authors.affiliation: Department of Anesthesiology, University of Maryland, Baltimore, MD.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Mazzeffi
authors.affiliation: Department of Anesthesiology, Massachusetts General Hospital, Boston, MA.
authors.forename: Shu Yang
authors.initials: SY
authors.lastname: Lu
authors.affiliation: Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Raymond M
authors.initials: RM
authors.lastname: Planinsic
authors.affiliation: Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Sakai
authors.affiliation: Department of Anesthesiology, University of Maryland, Baltimore, MD.
authors.forename: Kenichi A
authors.initials: KA
authors.lastname: Tanaka
mesh_terms: D001777:Blood Coagulation / Q000502:physiology*; D001778:Blood Coagulation Disorders / Q000097:blood* / Q000209:etiology; D001803:Blood Transfusion; D058625:End Stage Liver Disease / Q000097:blood* / Q000150:complications / Q000601:surgery*; D005170:Factor X / Q000032:analysis; D005260:Female; D006801:Humans; D019934:International Normalized Ratio; D016031:Liver Transplantation; D019520:Living Donors; D008297:Male; D008875:Middle Aged; D011517:Prothrombin Time / Q000379:methods*; D013916:Thrombelastography / Q000379:methods*; D055682:Viscoelastic Substances / Q000097:blood*
chemical_list: D055682:Viscoelastic Substances; D005170:Factor X