Predictions of Bleeding During Liver Transplantation With Thromboelastometry
Condition: Hemorrhage
MeSH terms: Hemorrhage
Study type: Observational [Patient Registry]

Summary: 
      Patients with cirrhosis present complex coagulation defects. Conventional coagulation tests
      (INR, platelets count) can not predict bleeding or blood product requirements during liver
      transplantation. Thromboelastometry (TEM)analyser measures the viscoelastic of the whole
      blood coagulation generation and lysis. TEM results are available more rapidly than
      conventional tests and give additional information regarding coagulation strengh, platelet
      function, and fibrinolysis.
    

Detailed description: 
      Historically, orthotopic liver transplantation (OLT) has been associated with major blood
      loss and the need for massive blood product transfusion . The cause of bleeding during OLT is
      multifactorial . The extensive surgical trauma plays a major role in the origin of bleeding.
      This bleeding can be accelerated by defects of the hemostatic system. Hemostatic defects can
      be divided into those present before the operation and those originating during the surgery.
      The latter can be classified according to the 3 main systems of hemostasis: coagulation,
      platelet function, and fibrinolysis. Hyperfibrinolysis is an important cause of non surgical
      bleeding during OLT .

      A significant decrease in blood loss and blood product requirements has been observed during
      OLT over the past 10 years . This decrease can be explained by increase experience,
      improvements in surgical and anesthetic techniques, and a better understanding of the various
      hemostatic abnormalities encountered during OLT.

      More than 10 years ago, Reyle-Hahn and Rossaint and Dupont et al stated that it is not
      necessary to correct coagulation defects before the anhepatic phase. More recently, some
      authors have a poor correlation between bleeding and the peripheral indices of coagulation in
      patients with chronic liver disease . These patients with cirrhosis are investigated by means
      of conventional tests for coagulation and primary hemostasis such as prothrombin time (INR),
      activated partial thromboplastin time (aPTT), platelet count, and skin bleeding time. Two
      important studies have raised serious questions about clinical use of INR in both measuring
      liver disease prognosis and in estimating bleeding risk thus calling into question many
      common and traditional clinical practices .

      Now, it is cleat that conventional tests of coagulation (INR, platelet count, fibrinogen) are
      not able to predict blood product transfusion requirements and bleeding during liver
      transplantation.

      A substantial body of evidence suggests that the use of blood products is associated with
      morbidity and mortality . Because 33% of liver recipients had acquired their liver disease
      through the transfusion of blood products , it is important to establish strategies aimed at
      decreasing blood losses and consequently the need for transfusion. The ability to predict
      intraoperative blood loss and transfusion requirements would be of great help to ensure
      adequate blood products and to enable appropriate therapy for patients at high risk of
      bleeding.

      The ROTEM (TEM) thromboelastometry analyzer based on throboelastographic principles ,
      measures the viscoelastic properties of whole blood coagulation generation and lysis. The
      instrument provides important global hemostatic information about the
      plasma-platelet-leucocyte interaction and clot tensile strength . TEM results are available
      more rapidly than those from laboratory-based conventional coagulation testing and also
      provide additional information regarding coagulation strength, platelet function, and
      fibrinolysis. Kang et al 39 using thromboelastogram (TEG) showed a decrease in red blood
      cells (RBC) use after the introduction of TEG monitoring.

      ROTEM analysis includes plasmatic coagulation and fibrinolytic factors and inhibitors, as
      well as all circulating blood cells and provides clinically important information about
      quality of the final blood clot.

      The aim of this observational study was to determine if ROTEM parameters were able to predict
      blood losses and transfusion of RBC during a liver transplantation.
    

Intervention name(s): ROTEM analysis
Intervention type(s): Other
Intervention description(s): 3 blood samples for ROTEM analysis
Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        every patient who had a liver transplantation
      
Keywords: liver transplantation, rotem, bleeding, transfusion