Factors influencing thrombelastography in pregnancy / 中南大学学报(医学版)

OBJECTIVES@#The number of gestational women has been increased in recent years, resulting in more adverse pregnancy outcomes. It is crucial to assess the coagulation function of pregnant women and to intervene in a timely manner. This study aims to analyze the influencing factors on thrombelastography (TEG) and explore the evaluation of TEG for gestational women.@*METHODS@#A retrospective study was conducted on 449 pregnant women who were hospitalized in the obstetrics department in Xiangya Hospital of Central South University from 2018 to 2020. We compared the changes on the TEG parameters among normal pregnant women between different age groups, different ingravidation groups, and different stages of pregnancy groups. The influence on TEG of hypertensive disorders in pregnancy (HDP) and gestational diabetes mellitus (GDM) as well as two diseases synchronization was explored.@*RESULTS@#Compared with the normal second trimester women, the R values and K values of TEG were increased, and α angle, CI values and LY30 values were decreased in third trimester women (all P<0.05). Compared with normal group, the R values and CI values of TEG of the HDP group have significant difference (both P<0.05). There were no significant difference of TEG between the GDM group, the HDP combined with GDM group and the normal group (all P>0.05). Multiple linear regression analysis showed that the influencing factors for R value in TEG were weeks of gestation (P<0.001) and mode of conception (P<0.05), for α angle was weeks of gestation (P<0.05), for MA value was mode of conception (P<0.05), and for CI value was weeks of gestation (P<0.05). The analysis of correlation between TEG with platelet (PLT) and coagulation routines represented that there was a correlation between TEG R values and activated partial thromboplastin time (APTT) (P<0.01), and negative correlation between TEG CI values and APTT (P<0.05). There was a negative correlation between TEG K values and FIB (P<0.05). The correlation of α angle (P<0.05), MA values (P<0.01) and CI values (P<0.05) with FIB were positive respectively.@*CONCLUSIONS@#The TEG parameters of 3 stages of pregnancy were different. The different ingravidation approach has effect on TEG. The TEG parameters were consistent with conventional coagulation indicators. The TEG can be used to screen the coagulation status of gestational women, recognize the abnormalities of coagulation and prevent the severe complication timely.

Predictive value of four items of new thrombus markers combined with conventional coagulation tests for thrombosis in antiphospholipid syndrome / 北京大学学报(医学版)

OBJECTIVE@#To explore the predictive value of four items of new thrombus markers combined with conventional coagulation tests for thrombosis in antiphospholipid syndrome.@*METHODS@#A total of 121 antiphospholipid syndrome (APS) patients who hospitalized at Peking University People's Hospital from March 2022 to January 2023 were selected and divided into thrombus group (50 cases) and nonthrombus group (71 cases) according to whether thrombosis occurred. The differences of laboratory characteristics including antiphospholipid antibodies were compared between the thrombotic and non-thrombotic groups. Chemiluminescent immunoassay was used to detect thrombomodulin (TM), thrombin-antithrombin complex (TAT), Plasmin-α2 plasmin inhibitor complex (PIC), and tissue plasminogen activator inhibitor complex (t-PAIC) in plasma from venous. The independent risk factors of thrombosis in patients with APS were determined using binary Logistic regression. Receiver operating characteristic (ROC) curve analysis was applied to evaluate the efficacy of each index on the prediction of thrombosis.@*RESULTS@#Compared with the patients without thrombosis, the patients with thrombosis were older [49 (32, 64) years vs. 36 (32, 39) years, P < 0.05]. The percentages of male, smoking, hypertension, and global antiphospholipid syndrome score (GAPSS)≥10 in the patients with thrombosis were significantly higher than those in the patients without thrombosis (P < 0.05). The positive rates of anticardiolipin antibody (aCL) and lupus anticoagulant (LA) in the thrombotic group were significantly higher than those in the non-thrombotic group (P < 0.05), and the levels of prothrombin time, activated partial thromboplastin time, fibrinogen, fibrin degradation product in the thrombotic group were significantly higher than those in the non-thrombotic group (P < 0.05).Among the thrombosis group, venous thrombosis accounted for 19 (38.00%), including deep vein thrombosis (16, 84.21%) and pulmonary embolism accounted (5, 26.32%); Arterial thrombosis accounted for 35 (70.00%), including myocardial infarction (6, 17.14%) cerebral infarction (30, 85.71%). The patients in the thrombotic group had significantly greater TM levels than those in the non-thrombotic group (P < 0.05).There were no significant dif-ferences between the two groups in TAT (Z=-1.420, P=0.156), PIC (Z=-0.064, P=0.949), and t-PAIC (Z=-1.487, P=0.137). Univariate and binary Logistic regression analysis of relevant variables showed that advanced age [OR=1.126, P=0.002], elevated TM [OR=1.325, P=0.048], prolonged prothrombin time (PT) [OR=4.127, P=0.008] were independent risk factors for thrombosis in the patients with APS. ROC curve analysis of the above three independent risk factors showed that the combined detection of age, PT and TM had the highest Yoden index (0.727) and sensitivity (83.0%), with a specificity of 89.7%.@*CONCLUSION@#TAT, PIC, TM, and t-PAIC may reflect thrombus formation from the coagulation system, fibrinolysis system, and endothelial system. The combined of age TM and PT is superior to the application of a single marker, which has diagnostic value for the early identification of APS thrombosis.

Analysis of APTT Mixing Test Results in Factor Ⅷ Inhibitor-Positive Hemophilia Patients / 中国实验血液学杂志

OBJECTIVE@#To analyze the results of activated partial thromboplastin time (APTT) mixing test in coagulation factor Ⅷ inhibitor-positive hemophilia patients, so as to increase the value of APTT mixing test in the screen of factor Ⅷ inhibitor.@*METHODS@#Eighty plasmas samples with different titers of coagulation factor Ⅷ inhibitors had been collected and diluted for routine immediate APTT mixing test and at 37 ℃ 2 hours incubation APTT mixing test. Fifteen samples were selected for immediate and normal temperature incubation for 15 min, 30min, 1 hour, 2 hours and 37 ℃ for 30 min, 1 hour, 2 hours APTT mixing test.@*RESULTS@#The results of APTT mixing test were significantly correlated with the titers of coagulation factor Ⅷ inhibitors. The ROC curve result showed that the best diagnostic cut-off value for 2 hours incubation APTT mixing test at 37 ℃ to determine the presence or absence of coagulation factor Ⅷ inhibitors was 43.8 s (sensitivity and specificity was 85.90% and 100%, respectively), while the best diagnostic cut-off value for distinguishing high-titer and low-titer Ⅷ inhibitors was 52.4 s (sensitivity and specificity was 98.18% and 95.65%, respectively). The critical coagulation factor Ⅷ inhibitor titer that could not be corrected by immediate APTT was 5.14 BU/ml, while that could not be corrected by 37 ℃ 2 hours incubation APTT was 1.31 BU/ml. Paired samples t -test was performed on the APTT mixing test results at different times and temperatures, and the differences were statistically significant (P < 0.05).@*CONCLUSIONS@#The APTT mixing test can be used as a screening index for coagulation factor Ⅷ inhibitors. APTT mixing test result shows a significant time-temperature dependence with lower titers of coagulation factor Ⅷ inhibitor. Patients with hemophilia who cannot be corrected by immediate APTT mixing test should be alert to the possibility of high titer of coagulation factor Ⅷ.

Congenital factor X deficiency: a retrospective analysis of 11 cases / 中华血液学杂志

Objective: To analyze the clinical characteristics, laboratory examination, diagnosis, treatment, and outcome of hereditary factor Ⅹ (FⅩ) deficiency. Methods: Clinical data of 11 patients with congenital FⅩ deficiency were retrospectively analyzed from July 2009 to February 2021. Results: There were 3 males and 8 females. Median age was 39 (5-55) years. The media duration of follow-up was 81.67 (1.87-142.73) months. Of the 11 patients, 10 had bleeding symptoms, 7 had ecchymosis or hemorrhage after skin bump, 7 had nosebleed, 6 had gingival hemorrhage, and 1 had muscle hematoma. Among the female patients, 6 had menorrhagia and 1 experienced bleeding after vaginal delivery. Family history of FⅩ deficiency was found in one case. Eight patients had a history of surgery, and four had postoperative bleeding. Laboratory findings were characterized by significantly prolonged activated partial thromboplastin time, prothrombin time, and decreased FⅩ activity (FⅩ∶C) . Four cases underwent gene mutation analysis and five new mutations were found. Four cases were treated with prothrombin complex concentrates (PCC) and seven cases with fresh frozen plasma (FFP) . One female patient had significantly reduced menstrual volume after PCC prophylactic therapy. One patient received FFP for prophylactic infusion with no bleeding during and after the operation. Conclusion: Most patients with congenital FⅩ deficiency had bleeding symptoms and there was no significant correlation between severity of bleeding symptoms and FⅩ∶C. Prophylaxis should be applied in patients with severe bleeding tendencies. Gene mutation test is significant for screening, diagnosis, and prognosis prediction of congenital FX deficiency.

Comparative Analysis of Thromboelastogram and Coagulation Items in Mongolian Patients with Thrombosis / 中国实验血液学杂志

OBJECTIVE@#To investigate the age distribution of Mongolian patients with cerebral infarction caused by thrombosis and the correlation and consistency between thromboelastography (TEG) and four parameters of coagulation.@*METHODS@#The age distribution of 298 Mongolian patients with cerebral infarction treated in Affiliated Hospital of Inner Mongolia Minzu University from January 2020 to December 2021 and their TEG, four items of routin coagulation and platelet count were analyzed retrospectively. The correlation and consistency of above-mentioned two detection methods were statistically analyzed.@*RESULTS@#The onset age of 298 Mongolian patients with cerebral infarction was mainly 61-70 years old, accounting for 38.3%, followed by 51-60 years old, accounting for 26.8%. The R time detected by TEG was linearly correlated with PT and APTT（r=0.186，r=0.152）. K value, MA value and α-Angle measured by TEG was linearly correlated with Fib (r=-0.364，r=0.616，r=0.359), K value, MA value and α-Angle measured by TEG was linearly correlated with Plt (r=0.318，r=0.519，r=0.301). The R time detected by TEG was consistent with PT and APTT, and the Kappa values were 0.252 (P<0.001), 0.336 (P<0.001). K, MA, and α-Angle measured by TEG was consistent with Fib, the Kappa values were 0.265 (P<0.001), 0.289 (P<0.001) and 0.290 (P<0.001), respectively; K、MA and α-Angle measured by TEG was consistent with Plt, the Kappa values were 0.276 (P<0.001), 0.285 (P<0.001) and 0.302 (P<0.001), respectively.@*CONCLUSION@#The onset age of Mongolian patients with cerebral infarction caused by thrombosis is mainly 61-70 years old, followed by 51-60 years old. The onset age shows a younger trend. There is a significant correlation between TEG and coagulation, but the consistency is weak, therefore, the two methods can not be replaced each other.

Effects of Leukapheresis on Hemostatic Function in Patients with Hyperleukocytic Leukemia / 中国实验血液学杂志

OBJECTIVE@#To analyze and compare the effects of leukapheresis on hemostatic function in patients with hyperleukocytic leukemia.@*METHODS@#A total of 139 patients with AML, ALL and CML who underwent leukapheresis from June 2009 to February 2020 and did coagulation test before and after operation were included in this study. The clearance efficiency of each group and the difference among three groups were evaluated, as well as hemostatic function including platelet counts, coagulation indicators, CDSS score and incidence of adverse events. The difference of hemostatic function caused by leukapheresis in different leukemia patients were compared.@*RESULTS@#After leukapheresis, the WBC counts were decreased significantly in the three groups of patients (P<0.001), and the clearance efficiency was highest in ALL patients. However, the platelet counts also were decreased significantly (AML:P＜0.001, ALL: P＜0.001, CML: P＜0.01) in the three groups of patients, particularly for acute leukemia patients with a positive correlation with WBC clearance efficiency(r=0.284). After leukapheresis, fibrinogen decreased, PT and APTT prolonged. For acute leukemia patients, higher CDSS score was related to an elevated incidence of bleeding events (P<0.05).@*CONCLUSION@#Leukapheresis is an effective method to decrease the leukemic burden, but it is necessary to monitor the impact on hemostatic function. It is recommended to assess the CDSS socre for acute leukemia patients, in order to identify the predictive value for bleedings.

Design of Detection Module in Coagulometers Based on Dual-magnetic Circuit Beads Method / 中国医疗器械杂志

Coagulometer, known as blood coagulation analyzer, is a product that can provide accurate test results for medical diagnosis and treatment analysis by detecting a series of items closely related to thrombosis and hemostasis in coagulation reaction. On the basis of previous traditional methods, and with our deep understanding about the principles of hemagglutination detection, we propose a hemagglutination detection method by using the dual-magnetic circuit beads method. Then, the corresponding hemagglutination detection module is designed. The coagulation time of plasma can be measured by detecting the movement of the magnetic beads when the magnetic field intensity is appropriate. The activated partial thromboplastin time(APTT) of plasma is tested when the most suitable magnetic field intensity is found. The results preliminarily show that this blood coagulation test method is valid and the corresponding test module has a potential value in business.

Coagulation Indexes and Their Prognostic Significance in Patients with Multiple Myeloma / 中国实验血液学杂志

OBJECTIVE@#To analyze the relationship between coagulation indexes and prognosis of patients with multiple myeloma (MM).@*METHODS@#A total of 99 newly diagnosed MM patients treated in Gansu Provincial Hospital from October 2017 to October 2019 were enrolled. Plasma thromboplastin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), D-dimer (D-D), platelet (PLT), and other laboratory indexes were detected. The relationship between coagulation indexes and clinical characteristics of MM patients was analyzed. The differences in survival rates among MM patients with different levels of coagulation indexes were compared, and the effect of each clinical index on the prognosis of MM patients was analyzed by univariate and multivariate.@*RESULTS@#Each coagulation index was correlated to sex, disease classification and stage, and β@*CONCLUSION@#Coagulation function is correlated with multiple clinical indicators of patients with MM and plays an important role in their prognosis.

Comparison of Plasma Components between Frozen Plasma and Fresh Frozen Plasma / 中国实验血液学杂志

OBJECTIVE@#To compare the plasma components of frozen plasma (FP) and fresh frozen plasma (FFP).@*METHODS@#Twenty samples of FP and 20 samples of FFP from Beijing Red Cross Blood Center were randomly selected. Immediately after plasma melting, 12 plasma components including coagulation factor, fibrinolytic system and anticoagulation protein were detected, including activated partial thromboplastin time (APTT), prothrombin time (PT), coagulation factor Ⅷ (FⅧ) activity, coagulation factor Ⅴ (FⅤ) activity, fibrinogen(FIB) level, ADAMTS-13 activity, von Willebrand factor(vWF) activity, D-dimer (D-dimer, DD), fibrin degradation products (FDP), antithrombin (AT), protein C (PC), and protein S (PS). All these coagulation components between the two types of plasma were compared and analyzed.@*RESULTS@#Compared with FFP, APTT in FP was significantly prolonged(t=3.428, P0.05).@*CONCLUSION@#FP can substitute FFP in the treatment of some diseases, although it is lack of some coagulation factors and anticoagulation protein.

Trastornos hereditarios de la coagulación en adolescentes con sangrado menstrual excesivo, ¿debemos evaluar la vía fibrinolítica? / Inherited bleeding disorders in adolescents with excessive menstrual bleeding: should we evaluate the fibrinolytic pathway?

Resumen: Introducción: El Sangrado Menstrual Excesivo (SME) es un problema frecuente en la adolescencia. La prevalencia de trastornos hereditarios de la coagulación (THC) como causa del SME no está bien establecida y la participación de defectos de la vía fibrinolítica ha sido poco explorada. Objetivo: Determinar la prevalencia de THC y defectos de la fibrinólisis en adolescentes con SME. Pacientes y Método: Se incluyeron 93 adolescentes, edad 11 a 18 años. Los antecedentes personales y familiares de sangra do se obtuvieron con un cuestionario estandarizado. Se controló exámenes: tiempo de protrom- bina (TP), tiempo de tromboplastina parcial activada (TTPa), estudio del factor Von Willebrand, recuento y función plaquetaria. Los pacientes que no fueron diagnosticados como THC, se evaluaron adicionalmente con el tiempo de lisis del coágulo. Resultados: 41 pacientes (44%) fueron diagnos ticados como THC: Enfermedad de Von Willebrand n = 28, defectos de la función plaquetaria n = 8, hemofilia leve n = 5. Se confirmó disminución del tiempo de lisis del coágulo en 31 pacientes. El 54% de pacientes diagnosticado como THC, tuvo SME como la primera manifestación hemorrágica. Conclusión: Estos resultados apoyan la necesidad de evaluación de la coagulación, incluyendo la vía fibrinolítica, en el estudio de adolescentes con SME.

Abstract: Introduction: Heavy Menstrual Bleeding (EMB) is a frequent problem in adolescence. The prevalence of inherited bleeding disorders (IBD) as a cause of EMB is not well established and the involvement of fibri nolytic pathway defects has been poorly explored. Objective: To determine the prevalence of IBD and fibrinolysis defects in adolescents with EMBs. Patients and Method: 93 adolescents (11 to 18 years old) were included. Personal and family history of bleeding were obtained through a standard ized questionnaire. The following lab tests were performed: prothrombin time (PT), activated partial thromboplastin time (aPTT), von Willebrand factor quantification, and platelet count and function. Those patients who were not diagnosed with IBD were further evaluated with clot lysis time assay. Results: 41 patients (44%) were diagnosed as IBD (Von Willebrand disease n = 28, platelet func tion defects n=8, mild hemophilia n = 5. Decreased clot lysis time was found in 31 patients. 54% of patients diagnosed with IBD had EMB as the first hemorrhagic manifestation. Conclusion: These results support the need to evaluate the coagulation process, including the fibrinolytic pathway in the study of adolescents with EMB.

A Retrospective Study on Unfractionated Bovine Heparin Safety in On-Pump Cardiac Surgery

Abstract Background: Heparin decreases the risks of thrombotic phenomena in extracorporeal circulation. However, it must present a robust safety profile itself, especially for bleeding. Contamination of porcine heparin demands an alternative source and consequent assessment of safety. Objective: To evaluate the safety of unfractionated bovine heparin during on-pump cardiac surgery. Methods: Descriptive, retrospective study, evaluating medical records from all patients who had on-pump cardiac surgery over four years. We observed the occurrence of bleeding, thrombocytopenia, postoperative vasoplegia, activated clotting time values and any other coagulation phenomena as safety profile parameters. Results: We evaluated 204 medical records reporting the use of unfractionated bovine heparin. 66.18% of the patients presented thrombocytopenia, 1.04% presented bleeding of more than 2000 mL in the first 24 hours of the postoperative period. One patient presented clots in the surgical field. Median activated clotting time was 137 seconds at baseline, 803 seconds after the first dose of heparin and, after protamine, it returns to similar baseline values, that is, 149.5 seconds. Conclusion: Unfractionated bovine heparin did not present unusual adverse effects and can be considered safe for on-pump cardiac surgery.

Reduction of FXIII during myelosuppression in acute leukemia after chemotherapy and adverse relation with bleeding events / 中华血液学杂志

Objective: To explore the relationship between plasma coagulation factor XIII (FXIII) and bleeding events. Methods: A total of 55 cases of acute leukemia (AL) at the myelosuppression phase after chemotherapy hospitalized in our hospital from August 2017 to March 2018 were enrolled, with 35 normal controls. The concentration of plasma coagulation factor XIII (FXIII) was detected by ELISA to determine the relationship between the plasma FXIII levels in AL patients at the myelosuppression phase after chemotherapy with bleeding events. Results: The level of FXIII in AL patients at the myelosuppression phase after chemotherapy was significantly lower than that in controls (P<0.001) . The level of FXIII was inversely related with the bleeding severity (the Spearman correlation coefficient -0.761) . Given the diagnosis cut-off point of FXIII concentration as 103.9 μg/L, the sensitivity of diagnosing bleeding in AL patients at the myelosuppression phase after chemotherapy was 0.939, and the specificity 0.909. Conclusion: AL patients at the myelosuppression phase after chemotherapy had low level of plasma FXIII, and patients with lower plasma FXIII associated with higher incidence and severity of bleeding. FXIII level was an independent influencing factor of bleeding in AL patients at the myelosuppression phase after chemotherapy.

Level of Coagulation Function Indexes and Its Clinical Significance in Patients with Lymphoplasmacytic Lymphoma / 中国实验血液学杂志

OBJECTIVE@#To analyze the level of coagulation function indexes in patients with lymphoplasmacytic lymphoma (LPL) and its clinical significance.@*METHODS@#The clinical data of 32 patients with initial LPL (LPL group) and physical examination data of 25 healthy persons (control group) who underwent physical examination in our hospital during the same period were collected. The differences of platelet (Plt), D-Dimer (D-D), fibrinogen (Fib), thrombin time (TT), prothrombin time (PT) and activated partial thrombin time (APTT) between the two groups were compared.@*RESULTS@#The Plt count in LPL group [ (137.06±40.14)×10/L] was significantly lower than that in control group [ (215.07±33.25)×10/L], D-D [ (1.01±0.16) mg/L, PT [ (13.01±1.37) s] and APTT [ (40.96±7.24) s] in LPL group were significantly higher than those in control group [ (0.37±0.09) mg/L, (11.96±0.87) s, (25.07±5.13) s] (P＜0.01); there was no significant difference in TT and Fib levels between the two groups (P＞0.05). There was no significant difference in Plt, D-D, Fib, AP, TT and APTT among LPL patients secreting different types of immunoglobulin (Ig) (P＞0.05). After treatment, the coagulation function of LPL patients returned to normal, and no death cases occurred due to hemorrhage or thrombosis.@*CONCLUSION@#LPL patients have hypercoagulable state blood and abnormal coagulation function, but which not closely relates to with the type of Ig secreted by patients.

Utilidad del tromboelastograma en pediatría: correlación con pruebas habituales de la coagulación / Usefulness of the thromboelastogram in children: correlation with habitual coagulation tests

INTRODUCCIÓN: Los exámenes habituales de coagulación evalúan distintos elementos de la hemostasia en forma par cial, y no traducen las interacciones celulares, lo que es especialmente sensible en pacientes críticos. Las técnicas viscoelásticas, como el tromboelastograma (TEG) muestran el proceso de coagulación completo, y están siendo evaluadas como exámenes de la coagulación global. OBJETIVO: determinar la correlación de los exámenes habituales de coagulación con los valores del TEG, en niños atendidos en una unidad de cuidados intensivos (UCI). PACIENTES Y MÉTODO: Se revisaron 238 TEG de pacientes <18 años, con evidencia de alteración de coagulación clínica y/o de laboratorio, hospitalizados en UCI. Se correlacionaron los valores de los parámetros del TEG con cada uno de los valores de los exámenes habituales de coagulación. Los exámenes se obtuvieron según protocolo, utilizando una muestra de sangre de 4,5 ml para TEG con equipo TEG® 5000 Thrombelastograph Hemostasis Sys tem, mediante un transductor electromagnético que permite la medición de la resistencia durante la formación y lisis del coágulo. El recuento de plaquetas se obtuvo utilizando método automatizado o microscopía con contraste de fase; el fibrinógeno, tiempo de protrombina y de tromboplastina parcial activada por métodos nefelométricos. RESULTADOS: 201 TEGs correspondientes a 59 pacientes. Se evidenció una correlación moderada a baja en todos los parámetros medidos. No se encontró co rrelación entre porcentaje de lisis del coágulo, ni firmeza del coágulo. CONCLUSIONES: Existe una baja correlación entre la información entregada por TEG y los exámenes de coagulación habituales, esto sugiere que el TEG aporta información diferente acerca del estado de coagulación de los pacientes críticos evaluados.

INTRODUCTION: Usual coagulation tests partially evaluate different elements of hemostasis, and do not translate cell interactions, which is an especially sensitive issue in critically ill patients. Viscoelastic measurement techniques, such as thromboelastogram (TEG) show the complete coagulation pro cess and are being evaluated as global coagulation tests. OBJECTIVE: To determine the correlation of the usual coagulation tests with the TEG values, in children treated in an intensive care unit (ICU). PATIENTS AND METHOD: We reviewed 238 TEGs of patients under 18 years of age, with evidence of clinical and/or laboratory coagulation alterations, who were hospitalized in the ICU. The TEG para meter values were correlated with each of the usual coagulation test values. The tests were obtained according to the protocol, using a 4.5 ml blood sample for TEG with TEG® 5000 Thrombelastograph Hemostasis System, through an electromagnetic transducer that allows the measurement of resis tance during the clot formation and lysis. Platelet count was obtained using an automated method or phase-contrast microscopy, and fibrinogen levels, prothrombin time, and partial thromboplastin time activated by nephelometric methods. RESULTS: 201 TEGs corresponding to 59 patients were re viewed. A moderate to low correlation was observed in all the measured parameters. No correlation was found between the percentages of clot lysis or clot firmness. CONCLUSIONS: There is a low corre lation between the information provided by TEG and the usual coagulation tests. This suggests that the TEG provides different information about the coagulation status of the evaluated critical patients.

Rotational thromboelastometry assessment of ballanced crystalloid, hydroxyethyl starch and gelatin effects on coagulation: a randomized trial / Tromboelastometria rotacional na avaliação dos efeitos de cristaloides balanceados, hidroxietilamido e gelatina na coagulação: estudo randômico

Abstract Background and objectives Modern crystalloid and colloid solutions are balanced solutions which are increasingly used in perioperative period. However, studies investigating their negative effect on whole blood coagulation are missing, and vivid debate is going on about which solution has the minimal coagulopathy effect. The aim of our study was to assess the effect of modern fluid solutions on whole blood coagulation using rotational thromboelastometry. Methods Blood samples were obtained from 30 patients during knee arthroscopy before and after administration of 500 mL of crystalloid, Hydroxyethyl Starch and gelatin according to the randomization. Rotational thromboelastometry (Extem, Intem and Fibtem tests) was used to assess negative effect of fluid solutions on whole blood coagulation. Results In Extem test, the initiation phase of fibrin clot formation represented by CT parameter was not influenced by any fluid solution (p > 0.05). The speed of clot formation represented by CFT and α angle was impaired by Hydroxyethyl Starch and gelatin but not by crystalloids (p < 0.05). The strength of formatted coagulum represented by MCF parameter was impaired both in Extem and Fibtem test by HES and in Fibtem also by crystalloids (p < 0.05). Intem test was not negatively influenced by any crystalloid or colloid solution in any parameter (p > 0.05). Conclusion Extem test appears to be sensitive to coagulopathy effect of modern colloids and crystalloids. Hydroxyethyl starch has the most obvious negative effect on clot formation followed by gelatin and finally by crystalloids. Intem test seems to be insensitive to adverse effect of modern colloids and crystalloids.

Resumo Justificativa e objetivos Os cristaloides e coloides modernos são soluções balanceadas e cada vez mais utilizadas no período perioperatório. No entanto, não há estudos que avaliem seu efeito negativo na coagulação do sangue total e o intenso debate sobre a solução que cause um efeito mínimo na coagulopatia permanece. O objetivo de nosso estudo foi avaliar o efeito das soluções líquidas modernas na coagulação do sangue total com o uso da tromboelastometria rotacional. Métodos De acordo com a randomização, amostras de sangue foram colhidas de 30 pacientes durante a artroscopia de joelho, antes e após a administração de 500 mL de cristaloides, hidroxietilamido e gelatina. A tromboelastometria rotacional (testes Extem, Intem e Fibtem) foi utilizada para avaliar o efeito negativo das soluções líquidas na coagulação do sangue total. Resultados No teste Extem, a fase de iniciação da formação de coágulos de fibrina representada pelo parâmetro CT não foi influenciada por qualquer solução líquida (p > 0,05). A velocidade da formação de coágulos representada pelo CFT e pelo ângulo α foi prejudicada pelo hidroxietilamido e pela gelatina, mas não pelos cristaloides (p < 0,05). A força do coágulo formatado representado pelo parâmetro MCF foi prejudicada tanto no teste Extem quanto no teste Fibtem pelo HES e no teste Fibtem também pelos cristaloides (p < 0,05). O teste Intem não foi influenciado negativamente por nenhuma solução cristaloide ou coloide em nenhum parâmetro (p > 0,05). Conclusão O teste Extem parece ser sensível ao efeito de coagulopatia dos coloides e cristaloides modernos. O hidroxietilamido apresentou o efeito negativo mais óbvio na formação do coágulo, seguido pela gelatina e finalmente pelos cristaloides. O teste Intem parece ser insensível ao efeito adverso dos coloides e cristaloides modernos.

Influência do tempo de centrifugação em testes de coagulação: tempo de protrombina e tempo de tromboplastina parcial / Influence of the centrifuge time in coagulation tests: prothrombin time and partial thromboplastin time

Objetivo: Analisar os testes de coagulação: tempo de protrombina (TP) e tempo de tromboplastina parcial (TTP) em diferentes tempos de centrifugação da amostra da biológica, com relação ao protocolo padrão do Clinical Laboratory Standards Institute (CLSI). Métodos: As amostras foram divididas em cinco alíquotas de 1 mL. Foi realizada a centrifugação em 15, 10, 5, 2 e 1 minuto, com velocidade de 1500 g. O TP e TTP foram imediatamente analisados em aparelho automatizado. Os plasmas foram analisados para presença de elementos residuais: eritrócitos, leucócitos e plaquetas. Resultados: Observou-se alteração dos valores do TP nos tempos de centrifugação 10, 5, 2 e 1 minuto e do TTP em 5, 2 e 1 minuto, com relação ao protocolo padrão. Na interpretação de Bland Altman, observou-se um viés significativo do limite clínico aceitável para o TP e para o TTP em todos os tempos de centrifugação, com relação ao protocolo padrão. Apenas no tempo de centrifugação de 15 minutos não foram encontradas células residuais nas amostras analisadas. Conclusão: O tempo de centrifugação de 15 minutos é o ideal para remoção completa das células sanguíneas residuais e para garantia da confiabilidade dos resultados dos testes de coagulação TP e TTP.

Objective: To analyze the coagulation tests: prothrombin test (PT) and partial thromboplastin time (PTT) in different centrifugation times of the sample, in relation to the standard protocol of the Clinical Laboratory Standards Institute (CLSI). Methods: The selected samples were splitted up into five aliquots of 1 mL. Centrifugation of these aliquots was carried out at 15, 10, 5, 2 and 1 minute at 1500 g. The PT and PTT were analyzed in an automated apparatus. The plasmas were analyzed for presence of residual elements: erythrocytes, leukocytes and platelets. Results: The results showed a change in the values of PT at the 10, 5, 2 and 1 minute centrifugation times and the PTT at 5, 2 and 1 minutes, relative to the standard protocol. In the interpretation of Bland Altman, a significant bias of the acceptable clinical limit for TP and TTP at all centrifugation times was observed, relative to the standard protocol. Only in the 15 minute centrifugation time no residual cells were found in the analyzed samples. Conclusion: The present study demonstrated that the 15-minute centrifugation time is ideal for complete removal of residual blood cells and to ensure the reliability of the results of the PT and PTT coagulation

Importancia de la orientación diagnóstica en hemofilia A adquirida / Adequate diagnosis of acquired hemophilia A

Acquired hemophilia A (AHA) is a rare and life-threatening autoimmune hemorrhagic disorder where autoantibodies are developed against factor VIII. An early diagnosis is challenging and mandatory: an immediate hemostatic control is required to reduce morbidity and mortality. Laboratory features of AHA are: presence of autoantibodies against factor VIII, prolonged activated partial thromboplastin time (with normal prothrombin time and thrombin time) and decreased factor VIII levels. In some cases, the results of laboratory tests may be incorrect due to errors in analysis, blood extraction or manipulation of samples; also worth of consideration are limitations in the measurement range and low sensitivity of the tests. This review highlights the importance of adequate screening in patients with suspected AHA to make an adequate diagnosis and reduce overall fatal outcomes.

Platelet function, coagulation and fibrinolysis in patients with previous coronary and cerebrovascular ischemic events

OBJECTIVES: Ischemic stroke (IS) or transient ischemic attack (TIA) history is present in 4-17% of patients with coronary artery disease (CAD). This subgroup of patients is at high risk for both ischemic and bleeding events. The aim of this study was to determine the role of platelet aggregability, coagulation and endogenous fibrinolysis in patients with CAD and previous IS or TIA. METHODS: A prospective case-control study that included 140 stable CAD patients divided into two groups: the CASE group (those with a previous IS/TIA, n=70) and the CONTROL group (those without a previous IS/TIA, n=70). Platelet aggregability (VerifyNow Aspirin® and VerifyNow P2Y12®), coagulation (fibrinogen and thromboelastography by Reorox®) and endogenous fibrinolysis (D dimer and plasminogen activator inhibitor-1) were evaluated. RESULTS: Patients in the CASE group presented significantly higher systolic blood pressure levels (135.84±16.09 vs 123.68±16.11, p<0.01), significantly more previous CABG (25.71% vs 10%, p=0.015) and significantly higher calcium channel blocker usage (42.86% vs 24.29%, p=0.02) than those in the control group. In the adjusted models, low triglyceride values, low hemoglobin values and higher systolic blood pressure were significantly associated with previous IS/TIA (CASE group). Most importantly, platelet aggregability, coagulation and fibrinolysis tests were not independently associated with previous cerebrovascular ischemic events (CASE group). CONCLUSION: Platelet aggregability, coagulation and endogenous fibrinolysis showed similar results among CAD patients with and without previous IS/TIA. Therefore, it remains necessary to identify other targets to explain the higher bleeding risk presented by these patients.

Diagnostic accuracy of thromboelastometry and its correlation with the HPLC-MS/MS quantification test

The aim of the study was to evaluate the diagnostic accuracy of thromboelastometry for assessing rivaroxaban concentrations. The accuracy of thromboelastometry was compared with the high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method, which is the gold standard for drug plasma monitoring (the reference standard). Forty-six clinically stable patients were treated with 10, 15, or 20 mg of rivaroxaban once daily (OD group) or 15 mg twice a day (BID group) (no particular indication for treatment). Patient samples were collected 2 h after the use of the medication (peak) and 2 h before the next dose (trough). The rivaroxaban plasma concentrations were determined via HPLC-MS/MS, and thromboelastometry was performed using a ROTEM® delta analyzer. There were significant prolongations in clotting time (CT) for the 10, 15, and 20 mg of rivaroxaban treatments in the OD groups. In the 15 mg BID group, the responses at the peak and trough times were similar. At the peak times, there was a positive correlation between the plasma concentration of rivaroxaban and CT (Spearman correlation rho=0.788, P<0.001) and clot formation time (rho=0.784, P<0.001), and a negative correlation for alpha angle (rho=−0.771, P<0.001), amplitude after 5 min (rho=−0.763, P<0.001), and amplitude after 10 min (rho=−0.680, P<0.001). The CT presented higher specificity and sensitivity using the cut-off determined by the receiver characteristics curve. ROTEM has potential as screening tool to measure possible bleeding risk associated with rivaroxaban plasma levels.