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Sandro Rizoli - One of the best experts on this subject based on the ideXlab platform.
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Thromboelastography and rotational thromboelastometry for the surgical intensivist a narrative review
Journal of Trauma-injury Infection and Critical Care, 2019Co-Authors: Byron C Drumheller, Sandro Rizoli, Deborah M Stein, Laura J Moore, Mitchell J CohenAbstract:BACKGROUNDViscoelastic tests (VETs), specifically Thromboelastography (TEG) and rotational thromboelastometry (ROTEM), are gaining popularity in the management of critically ill surgical patients with hemorrhage or thrombosis due to their comprehensive characterization of the coagulation process and
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effect of Thromboelastography teg and rotational thromboelastometry rotem on diagnosis of coagulopathy transfusion guidance and mortality in trauma descriptive systematic review
Critical Care, 2014Co-Authors: Bartolomeu Nascimento, Sandro Rizoli, Ajith Kumar Shankarakutty, Neill K J AdhikariAbstract:Introduction The understanding of coagulopathies in trauma has increased interest in Thromboelastography (TEG®) and thromboelastometry (ROTEM®), which promptly evaluate the entire clotting process and may guide blood product therapy. Our objective was to review the evidence for their role in diagnosing early coagulopathies, guiding blood transfusion, and reducing mortality in injured patients.
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thrombelastography teg practical considerations on its clinical use in trauma resuscitation
Scandinavian Journal of Trauma Resuscitation and Emergency Medicine, 2013Co-Authors: Luis Teodoro Da Luz, Bartolomeu Nascimento, Sandro RizoliAbstract:Thrombelastography is a laboratorial test that measures viscoelastic changes of the entire clotting process. There is growing interest in its clinical use in trauma resuscitation, particularly for managing acute coagulopathy of trauma and assisting decision making concerning transfusion. This review focuses on the clinical use of thrombelastography in trauma, with practical points to consider on its use in civilian and military settings. A search in the literature using the terms “thrombelastography AND trauma” was performed in PUBMED database. We focused the review on the main clinical aspects of this viscoelastic method in diagnosing and treating patients with acute coagulopathy of trauma during initial resuscitation. Thrombelastography is not a substitute for conventional laboratorial tests such as INR and aPTT but offers additional information and may guide blood transfusion. Thrombelastography can be used as a point of care test but requires multiple daily calibrations, should be performed by trained personnel and its technique requires standardization. While useful partial results may be available in minutes, the whole test may take as long as other conventional tests. The most important data provided by thrombelastography are clot strength and fibrinolysis. Clot strength measure can establish whether the bleeding is due to coagulopathy or not, and is the key information in thrombelastography-based transfusion algorithms. Thrombelastography is among the few tests that diagnose and quantify fibrinolysis and thus guide the use of anti-fibrinolytic drugs and blood products such as cryoprecipitate and fibrinogen concentrate. It may also diagnose platelet dysfunction and hypercoagulability and potentially prevent inappropriate transfusions of hemostatic blood products to non-coagulopathic patients. Thrombelastography has characteristics of an ideal coagulation test for use in early trauma resuscitation. It has limitations, but may prove useful as an additional test. Future studies should evaluate its potential to guide blood transfusion and the understanding of the mechanisms of trauma coagulopathy.
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Thrombelastography (TEG^®): practical considerations on its clinical use in trauma resuscitation
Scandinavian Journal of Trauma Resuscitation and Emergency Medicine, 2013Co-Authors: Luis Teodoro Da Luz, Bartolomeu Nascimento, Sandro RizoliAbstract:Background Thrombelastography is a laboratorial test that measures viscoelastic changes of the entire clotting process. There is growing interest in its clinical use in trauma resuscitation, particularly for managing acute coagulopathy of trauma and assisting decision making concerning transfusion. This review focuses on the clinical use of thrombelastography in trauma, with practical points to consider on its use in civilian and military settings. Methods A search in the literature using the terms “thrombelastography AND trauma” was performed in PUBMED database. We focused the review on the main clinical aspects of this viscoelastic method in diagnosing and treating patients with acute coagulopathy of trauma during initial resuscitation. Results Thrombelastography is not a substitute for conventional laboratorial tests such as INR and aPTT but offers additional information and may guide blood transfusion. Thrombelastography can be used as a point of care test but requires multiple daily calibrations, should be performed by trained personnel and its technique requires standardization. While useful partial results may be available in minutes, the whole test may take as long as other conventional tests. The most important data provided by thrombelastography are clot strength and fibrinolysis. Clot strength measure can establish whether the bleeding is due to coagulopathy or not, and is the key information in thrombelastography-based transfusion algorithms. Thrombelastography is among the few tests that diagnose and quantify fibrinolysis and thus guide the use of anti-fibrinolytic drugs and blood products such as cryoprecipitate and fibrinogen concentrate. It may also diagnose platelet dysfunction and hypercoagulability and potentially prevent inappropriate transfusions of hemostatic blood products to non-coagulopathic patients. Conclusions Thrombelastography has characteristics of an ideal coagulation test for use in early trauma resuscitation. It has limitations, but may prove useful as an additional test. Future studies should evaluate its potential to guide blood transfusion and the understanding of the mechanisms of trauma coagulopathy.
Bartolomeu Nascimento - One of the best experts on this subject based on the ideXlab platform.
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effect of Thromboelastography teg and rotational thromboelastometry rotem on diagnosis of coagulopathy transfusion guidance and mortality in trauma descriptive systematic review
Critical Care, 2014Co-Authors: Bartolomeu Nascimento, Sandro Rizoli, Ajith Kumar Shankarakutty, Neill K J AdhikariAbstract:Introduction The understanding of coagulopathies in trauma has increased interest in Thromboelastography (TEG®) and thromboelastometry (ROTEM®), which promptly evaluate the entire clotting process and may guide blood product therapy. Our objective was to review the evidence for their role in diagnosing early coagulopathies, guiding blood transfusion, and reducing mortality in injured patients.
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thrombelastography teg practical considerations on its clinical use in trauma resuscitation
Scandinavian Journal of Trauma Resuscitation and Emergency Medicine, 2013Co-Authors: Luis Teodoro Da Luz, Bartolomeu Nascimento, Sandro RizoliAbstract:Thrombelastography is a laboratorial test that measures viscoelastic changes of the entire clotting process. There is growing interest in its clinical use in trauma resuscitation, particularly for managing acute coagulopathy of trauma and assisting decision making concerning transfusion. This review focuses on the clinical use of thrombelastography in trauma, with practical points to consider on its use in civilian and military settings. A search in the literature using the terms “thrombelastography AND trauma” was performed in PUBMED database. We focused the review on the main clinical aspects of this viscoelastic method in diagnosing and treating patients with acute coagulopathy of trauma during initial resuscitation. Thrombelastography is not a substitute for conventional laboratorial tests such as INR and aPTT but offers additional information and may guide blood transfusion. Thrombelastography can be used as a point of care test but requires multiple daily calibrations, should be performed by trained personnel and its technique requires standardization. While useful partial results may be available in minutes, the whole test may take as long as other conventional tests. The most important data provided by thrombelastography are clot strength and fibrinolysis. Clot strength measure can establish whether the bleeding is due to coagulopathy or not, and is the key information in thrombelastography-based transfusion algorithms. Thrombelastography is among the few tests that diagnose and quantify fibrinolysis and thus guide the use of anti-fibrinolytic drugs and blood products such as cryoprecipitate and fibrinogen concentrate. It may also diagnose platelet dysfunction and hypercoagulability and potentially prevent inappropriate transfusions of hemostatic blood products to non-coagulopathic patients. Thrombelastography has characteristics of an ideal coagulation test for use in early trauma resuscitation. It has limitations, but may prove useful as an additional test. Future studies should evaluate its potential to guide blood transfusion and the understanding of the mechanisms of trauma coagulopathy.
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Thrombelastography (TEG^®): practical considerations on its clinical use in trauma resuscitation
Scandinavian Journal of Trauma Resuscitation and Emergency Medicine, 2013Co-Authors: Luis Teodoro Da Luz, Bartolomeu Nascimento, Sandro RizoliAbstract:Background Thrombelastography is a laboratorial test that measures viscoelastic changes of the entire clotting process. There is growing interest in its clinical use in trauma resuscitation, particularly for managing acute coagulopathy of trauma and assisting decision making concerning transfusion. This review focuses on the clinical use of thrombelastography in trauma, with practical points to consider on its use in civilian and military settings. Methods A search in the literature using the terms “thrombelastography AND trauma” was performed in PUBMED database. We focused the review on the main clinical aspects of this viscoelastic method in diagnosing and treating patients with acute coagulopathy of trauma during initial resuscitation. Results Thrombelastography is not a substitute for conventional laboratorial tests such as INR and aPTT but offers additional information and may guide blood transfusion. Thrombelastography can be used as a point of care test but requires multiple daily calibrations, should be performed by trained personnel and its technique requires standardization. While useful partial results may be available in minutes, the whole test may take as long as other conventional tests. The most important data provided by thrombelastography are clot strength and fibrinolysis. Clot strength measure can establish whether the bleeding is due to coagulopathy or not, and is the key information in thrombelastography-based transfusion algorithms. Thrombelastography is among the few tests that diagnose and quantify fibrinolysis and thus guide the use of anti-fibrinolytic drugs and blood products such as cryoprecipitate and fibrinogen concentrate. It may also diagnose platelet dysfunction and hypercoagulability and potentially prevent inappropriate transfusions of hemostatic blood products to non-coagulopathic patients. Conclusions Thrombelastography has characteristics of an ideal coagulation test for use in early trauma resuscitation. It has limitations, but may prove useful as an additional test. Future studies should evaluate its potential to guide blood transfusion and the understanding of the mechanisms of trauma coagulopathy.
Kenichi A Tanaka - One of the best experts on this subject based on the ideXlab platform.
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clinical applicability of rapid thrombelastography and functional fibrinogen thrombelastography to adult liver transplantation
Liver Transplantation, 2014Co-Authors: Kenichi A Tanaka, Ezeldeen Abuelkasem, Raymond M Planinsic, Tetsuro SakaiAbstract:Unlike kaolin thrombelastography (k-TEG), the clinical utility of rapid thrombelastography (r-TEG) and functional fibrinogen thrombelastography (FF-TEG) has not been tested in liver transplantation (LT). These thrombelastography techniques were simultaneously performed at the time of the skin incision (the baseline) and 30 minutes after graft reperfusion (III + 30) for 27 consecutive adult LT patients. k-TEG and r-TEG parameters [alpha angle (α) and maximum amplitude of the clot (MA)] were compared in addition to the assay time. Estimated FF-TEG fibrinogen levels were compared with plasma fibrinogen measurements. At the baseline, the values of Spearman's correlation coefficient (r) between k-TEG and r-TEG were moderate for α (r = 0.40, P = 0.06) and strong for MA (r = 0.90, P < 0.01). At III + 30, r was 0.46 (P < 0.05) for α and 0.80 (P < 0.01) for MA. The average time required to measure MA via r-TEG was decreased in comparison with k-TEG [from 29.7 to 21.6 minutes at the baseline (a 22% reduction) and from 29.6 to 22.9 minutes at III + 30 (a 23% reduction)]. FF-TEG correlated strongly with the plasma fibrinogen level at the baseline (r = 0.90, P < 0.01); however, FF-TEG overestimated the fibrinogen level at III + 30 (r = 0.58, P = 0.01). In conclusion, in adult LT, r-TEG correlates with k-TEG strongly for MA but only moderately for α. FF-TEG estimates the plasma fibrinogen level well at the baseline; however, it must be interpreted with caution because of its overestimation after graft reperfusion when the plasma fibrinogen level often decreases to less than 100 mg/dL. Liver Transpl 20:1097–1105, 2014. © 2014 AASLD.
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principles and practice of Thromboelastography in clinical coagulation management and transfusion practice
Transfusion Medicine Reviews, 2012Co-Authors: Kenichi A Tanaka, Daniel Bolliger, Manfred D SeebergerAbstract:In the recent years, Thromboelastography has become a popular monitoring device for hemostasis and transfusion management in major surgery, trauma, and hemophilia. Thromboelastography is performed in whole blood and assesses the viscoelastic property of clot formation under low shear condition. Thromboelastography can be performed with a variety of activator and inhibitors at different concentrations representing the most important factors for different intervals and clot formation variables reported in multiple studies and algorithms. Furthermore, fibrinogen levels and platelet counts have a major influence on thromboelastographic variables. In addition, differences in patient populations, devices, and preanalytical conditions contribute to some conflicting findings in different studies.
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the effects of platelet count on clot retraction and tissue plasminogen activator induced fibrinolysis on thrombelastography
Anesthesia & Analgesia, 2005Co-Authors: Nobuyuki Katori, Fania Szlam, Kenichi A Tanaka, Jerrold H LevyAbstract:Clot retraction and fibrinolysis may present as a decrease in amplitude on thrombelastography (TEG®). The former represents normal or hyperactive platelet function, and the latter represents a fibrinolytic state. It is important to distinguish clot retraction from fibrinolysis because the treatment
Vance G Nielsen - One of the best experts on this subject based on the ideXlab platform.
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thrombelastographic method to quantify the contribution of factor xiii to coagulation kinetics
Blood Coagulation & Fibrinolysis, 2007Co-Authors: Vance G Nielsen, James K Kirklin, Hugh Hoogendoorn, Truitt C Ellis, William L HolmanAbstract:Factor XIII (FXIII) plays a critical role in clot strength, and FXIII deficiency or excess is associated with hemorrhage or thrombosis, respectively. Our goal was to design a thrombelastography-based method to characterize the effects of FXIII on plasma clot strength. Normal human plasma was exposed to 0 or 200 mug/ml anti-FXIII antibodies for 20 min prior to celite activation and calcium addition. Other plasma had addition of fibrinogen (625 mg/dl)/FXIII (2 U/ml) or 30% dilution with hydroxyethyl starch before exposure to 0 or 200 mug/ml anti-FXIII antibodies. Thromboelastography was performed and data were collected until stable clot strength was observed. The exposure of normal plasma to anti-FXIII antibodies resulted in a significant (P < 0.05) decrease in clot strength (63%) compared with plasma without antibodies. Further samples exposed to anti-FXIII antibodies had clot strength no different from FXIII-deficient plasma. The FXIII-mediated clot strength varied between 44 and 50% in hypercoagulable and hypocoagulable plasma, respectively. In conclusion, the present investigation successfully demonstrated a novel method to detect the impact of FXIII activity in plasma samples. Further actuarial investigation will be required to determine the utility of this approach in the diagnosis and treatment of patients with either acquired FXIII deficiency or excess and concordant coagulopathy.
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effects of aprotinin on plasma coagulation kinetics determined by thrombelastography role of factor xi
Acta Anaesthesiologica Scandinavica, 2006Co-Authors: Vance G NielsenAbstract:Background: Aprotinin is commonly administered in settings involving cardiopulmonary bypass and liver transplantation to decrease peri-operative bleeding. Thrombelastography has been utilized to monitor coagulation in these settings, and aprotinin delays clot initiation, presumably by inhibiting kallikrein; however, aprotinin also inhibits Factor XI (FXI), a contact system protein. Thus, it was hypothesized that celite-activated thrombelastography coagulation kin-etics would be decreased via aprotinin-mediated FXI inhibition. Methods: Citrated normal plasma and prekallikrein-deficient (<1% normal activity) plasma were exposed to 0, 200, 400 or 800 kallikrein inhibitory units (KIU)/ml (n = 6 per condition). Samples were recalcified and celite-activated in a thrombelastograph, with clot initiation (R, s) determined. To confirm contact system specificity, additional prekallikrein-deficient samples with 0 or 800 KIU/ml aprotinin were activated with tissue factor (n = 4 per condition). Results: Exposure of celite-activated, normal plasma to aprotinin 0, 200, 400 or 800 KIU/ml resulted in R values of 167 ± 14, 253 ± 10, 293 ± 22 and 349 ± 21 s, respectively, which were significantly different from one another (P < 0.05). Exposure of celite-activated, prekallikrein-deficient plasma to aprotinin 0, 200, 400 or 800 KIU/ml resulted in R values of 366 ± 15, 630 ± 64, 698 ± 46 and 850 ± 47 s, respectively, which were significantly different from one another (P < 0.05). There were no significant differences in R values between tissue factor-activated, prekallikrein-deficient plasma samples with 0 or 800 KIU/ml aprotinin. Conclusions: These data support a role for the inhibition of FXI as the mechanism for aprotinin-mediated delayed contact system clot initiation determined by thrombelastography.
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effects of coagulation factor deficiency on plasma coagulation kinetics determined via thrombelastography critical roles of fibrinogen and factors ii vii x and xii
Acta Anaesthesiologica Scandinavica, 2005Co-Authors: Vance G Nielsen, Benjamin M Cohen, E CohenAbstract:Background: Thrombelastography (TEG®) is used to assess coagulopathy. However, a comprehensive characterization of the effects of specific coagulation factor deficiencies and mode of activation on TEG® data does not exist. Methods: Thrombelastography® was performed for 15 min with control plasma and plasmas deficient (<1% activity) in Factors II, V, VII, VIII, IX, X, XI, XII, or XIII activated with celite (0.28 mg ml−1) or tissue factor (TF, 0.1%) (n = 6 per condition). Additional fibrinogen concentration activity (75–345 mg dl−1) and Factor II, VII, X and XII activity-response relationships (1%, 6.25%, 12.5%, 25%, 50% and 100% activity) were obtained (n = 8 per condition). Thrombelastography® parameters included reaction time (R), angle (α), and clot strength (A, amplitude; G, elastic modulus). Results: Celite activation of FXII-deficient plasma, TF activation of FVII-deficient and FX-deficient plasma, and celite or TF activation of FII-deficient plasma resulted in an almost undetectable clot. Compared to control values, celite activation of plasmas deficient in FXI, FIX and FVIII resulted in prolonged R and decreased α values, whereas TF activation resulted in decreased α values. Celite and TF activation of FV-deficient plasma resulted in prolonged R and decreased α values, whereas FXIII-deficient plasma had decreased α, A and G-values compared to control values. Conclusions: The fundamental finding of this study is that coagulation factor deficiencies affect TEG® parameters in both a factor-dependent and activation-dependent fashion. Utilizing both celite and TF activation improves the diagnostic power of TEG®. Based on such TEG® data, more targeted administration of blood products could potentially help improve perioperative hemostatic outcomes.
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evaluation of the contribution of platelets to clot strength by Thromboelastography in rabbits the role of tissue factor and cytochalasin d
Anesthesia & Analgesia, 2000Co-Authors: Vance G Nielsen, Brian T Geary, Manuel S BairdAbstract:UNLABELLED The contribution of platelets and soluble clotting components to clot strength has been the focus of several clinical studies using Thromboelastography; it would, therefore, be beneficial to develop an animal model with which to mechanistically approach hemostatic disorders. Thus, we proposed to determine if the contribution of platelet function (G(P), dyne/cm(2)) and soluble components of the coagulation pathway to total clot strength (G(T)) in rabbits were similar to those in humans. Blood was sampled from the ear arteries of conscious rabbits (n = 12); 350 microL of the blood was placed in a thromboelastograph. Ten microliters of normal saline, cytochalasin D (an inhibitor of microtubule function, 10 microM final concentration), or tissue factor (a potent stimulator of platelet function, 0.00625% final concentration) was added to the blood sample, and Thromboelastography performed for 1 h. The G(T) (mean +/- SD) was significantly (P < 0.001) different among samples exposed to normal saline, cytochalasin D, or tissue factor, with G(T) values of 7238 +/- 1432, 937 +/- 372, and 16,556 +/- 3314, respectively. G(P) was responsible for 87% and 94% of G(T) in the absence or presence of tissue factor, respectively. G(P) did not significantly correlate with platelet concentration in the absence or presence of tissue factor. The contribution of G(P) to G(T) is similar to that observed in humans. IMPLICATIONS Rabbits may serve as a model of hemostasis that closely approximates human situations to mechanistically determine the etiology of coagulopathy. The contribution of platelet function to total clot strength is similar to that observed in humans.
Neill K J Adhikari - One of the best experts on this subject based on the ideXlab platform.
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effect of Thromboelastography teg and rotational thromboelastometry rotem on diagnosis of coagulopathy transfusion guidance and mortality in trauma descriptive systematic review
Critical Care, 2014Co-Authors: Bartolomeu Nascimento, Sandro Rizoli, Ajith Kumar Shankarakutty, Neill K J AdhikariAbstract:Introduction The understanding of coagulopathies in trauma has increased interest in Thromboelastography (TEG®) and thromboelastometry (ROTEM®), which promptly evaluate the entire clotting process and may guide blood product therapy. Our objective was to review the evidence for their role in diagnosing early coagulopathies, guiding blood transfusion, and reducing mortality in injured patients.
