2014 Consensus conference on viscoelastic test–based transfusion guidelines for early trauma resuscitation

Abstract

There has been an increased interest in the use of viscoelastic testing to guide blood product replacement during the acute resuscitation of the injured patient. Currently, no uniformly accepted guidelines exist for how this technology should be integrated into clinical care. In September 2014, an international multidisciplinary group of leaders in the field of trauma coagulopathy and resuscitation was assembled for a 2-day consensus conference in Philadelphia, Pennsylvania. This panel included trauma surgeons, hematologists, blood bank specialists, anesthesiologists, and the lay public.Nine questions regarding the impact of viscoelastic testing in the early resuscitation of trauma patients were developed before the conference by panel consensus. Early use was defined as baseline viscoelastic test result thresholds obtained within the first minutes of hospital arrival-when conventional laboratory results are not available. The available data for each question were then reviewed in person using standardized presentations by the expert panel. A consensus summary document was then developed and reviewed by the panel in an open forum. Finally, a two-round Delphi poll was administered to the panel of experts regarding viscoelastic thresholds for triggering the initiation of specific treatments including fibrinogen, platelets, plasma, and prothrombin complex concentrates. This report summarizes the findings and recommendations of this consensus conference.

Fixed ratio versus goal-directed therapy in trauma

“…An expert panel recently recommended that VETs should be used early in trauma resuscitation to identify injured patients with systemic hyperfibrinolysis, and it was clearly stated that normal lysis in VETs does not rule out profibrinolytic activation [44]. Thus, withholding antifibrinolytic therapy based on VETs is not justified.…”

“…For example, TEG findings suggest that clot lysis of more than 3% 30 min after maximum clot strength has been reached is associated with higher bleeding rates, increased transfusion requirements and unfavorable outcomes [55,56]. More rapidly obtainable VET parameters have been suggested as a surrogate for profibrinolytic activation; these include clot amplitude after 5 min running time (CA5) of less than 35 mm and, importantly, a flat line in extrinsically activated test plus cytochalasin D that inhibits platelet contribution to clot firmness (FIBTEM) [44] (Figs 1 and 2). www.co-anesthesiology.com…”

“…Maximum clot firmness (MCF) demonstrates the interaction between the fibrin network, activated platelets, and activated factor XIII [44,45]. Thus, diminished clot strength implies alterations in the number and/or function of platelets or impairment of fibrin polymerization [45], and is associated with increased bleeding rates, higher transfusion requirements, and increased mortality [60][61][62][63][64].…”

“…VETs are highly specific for hyperfibrinolysis, with time of onset and magnitude of clot lysis strongly related to poor outcomes [52][53][54]; however, these tests have a poor sensitivity [44] and identification of hyperfibrinolysis by VET results may take considerable time. For example, TEG findings suggest that clot lysis of more than 3% 30 min after maximum clot strength has been reached is associated with higher bleeding rates, increased transfusion requirements and unfavorable outcomes [55,56].…”

“…Furthermore, VETs identify hemostatic deficiencies substantially faster and more accurately than SCTs [44][45][46][47]. VET analyses are performed in whole blood, which avoids preanalytic preparation of the samples and, in contrast to plasma-based SCTs, corpuscular blood elements remain in place.…”