TEG improves anticoagulation management during cardiopulmonary bypass complicated by antiphospholipid syndrome

Variations in thromboelastography levels in blood exposed to membrane oxygenators

IntroductionThromboelastography (TEG), which indicates hemostatic ability, is useful for monitoring coagulation during extracorporeal circulation (ECC). However, the extent to which TEG levels are independently affected by ECC exposure remains unclear. To determine the effects of TEG levels in blood exposed to a membrane oxygenator, we performed in vitro experiments using whole human blood with ECC circuits including a membrane oxygenator.MethodsBlood provided by healthy volunteers was heparinized and circulated in three types of experimental circuits: polymer-coating, heparin-coating (HC), or non-coating (NC) membrane oxygenators (five of each type). Thromboelastography tests using a global hemostasis assay were performed at 3, 6, 12, and 24 h of circulation in each experiment. During TEG, the sampled blood was reversed with 0.05 mg of protamine. One-way analysis of variance (ANOVA) and two-way repeated measures ANOVA were performed to evaluate trends in circulation duration and coating types, respectively.ResultsCitrated kaolin with heparinase reaction times (CKHR) were significantly shortened at 6 and 12 h but prolonged at 24 h. The maximum amplitude for citrated kaolin with heparinase (CKHMA) was magnified from 6 to 12 h. Regarding the coating type, a significant difference was observed between HC and NC in CKHR at 6 h, but significance was not noted in other comparisons of coating types in CKHR and CKHMA.ConclusionsThromboelastography data indicated that the hemostatic capability of blood exposed to membrane surfaces was maintained after 12 h of circulation. The effects on TEG data in terms of coating type remain to be determined.

Clinical evaluation of hypercoagulability in advanced malignant tumors using thromboelastography and conventional coagulation tests

This study compares the diagnostic value of conventional coagulation tests (CCTs) and thromboelastography (TEG) for high blood coagulation states in advanced malignant tumors and to explore the diagnostic efficacy of their combination. In this study, 120 patients with advanced malignancy were divided into hypercoagulable state (n = 62) and non-hypercoagulable state (n = 58) groups. Traditional coagulation tests or CCTs (including prothrombin time, activated partial thromboplastin time, international normalized ratio, fibrinogen, D-dimer, and platelet count) were conducted. Simultaneously, TEG parameters, such as kinetic time, reaction time, clotting angle, maximum amplitude, and coagulation index, were assessed. Baseline demographic and pathological data were also collected. The role of conventional coagulation indicators, TEG indicators, and their combination in diagnosing high blood coagulation states was explored. The diagnostic efficiency was evaluated by constructing curves and calculating the area under the curve (AUC). Among 120 patients with advanced malignancy, 51.67% (62/120) had a hypercoagulable state. Among CCTs, activated partial thromboplastin time, D-dimer, and platelet count were associated with a hypercoagulable state, whereas no significant differences were found in other indicators. Among TEG parameters, maximum amplitude, reaction time, and clotting angle were associated with a hypercoagulable state, whereas kinetic time and coagulation index were not significantly different. The combined use of CCTs and TEG parameters was more effective in diagnosing hypercoagulable states than either test alone. The AUC values for the diagnostic efficacy of the CCTs, TEG, and TEG combined with CCTs for the diagnosis of hypercoagulable transitions in blood were 0.825, 0.744, and 0.947, respectively, with the highest AUC value in the combined test group. This study indicates that TEG parameters were highly correlated with hypercoagulability in patients with malignant tumors. The combined use of CCTs and TEG parameters is more effective for diagnosing hypercoagulability. These results can guide the clinical management and treatment of patients with malignant tumors.

Evaluation of the Safety and Efficacy of a Novel Thrombin Containing Combination Hemostatic Powder Using a Historical Control

This clinical study compares 2 hemostatic agents, a novel combination powder (CP) (HEMOBLAST^™ Bellows) and an established polysaccharide starch powder (PP) (Arista^™ AH) to assess the usefulness of CP. Retrospective comparative analysis of CP (July 2018 to July 2019, 68 patients) to PP (January 2011 to January 2013, 94 patients) in cardiothoracic patients was performed using linear regression models adjusting for age, sex, and procedure type for the endpoints: blood loss; protamine to skin closure time (hemostasis time); chest tube output and blood products required 48 hours postoperatively; ICU stay; postoperative comorbidities; and 30 day mortality. 162 patients (108 M: 54 F) underwent 162 cardiothoracic surgical procedures including: transplantation (n = 44), placement of ventricular assist device (n = 87), and others (n = 31). Use of CP compared to PP (Estimated Mean Difference [95% CI], P-value) produced significant reductions: blood loss (mL) (-886.51 [-1457.76, -312.26], P = 0.003); protamine to skin closure time (min) (-16.81 [-28.03, -5.59], P = 0.004); chest tube output (48 hrs, mL) (-445.76 [-669.38, -222.14], P < 0.001); packed red blood cell transfusions (units) (-0.98 [-1.56, -0.4], P = 0.001); and postoperative comorbidities (-0.31 [-0.55, -0.07], P = 0.012). There were no differences in the ICU stay (4.07 [-2.01, 10.15], P = 0.188) or 30-day mortality (0.57 [0.20, 1.63], P = 0.291). The use of CP in complex cardiothoracic operations resulted in improved hemostasis and significant clinical benefits in blood loss, transfusion requirements, morbidity, and time in operating room.

Monitoring of anticoagulation in thrombotic antiphospholipid syndrome

Anticoagulation is central to the management of thrombotic antiphospholipid syndrome (APS). The standard anticoagulant treatment for thrombotic APS is life-long warfarin or an alternative vitamin K antagonist. The role of direct oral anticoagulants for thrombotic APS is not established due to the lack of definitive evidence and has recently been addressed in international guidance. Other anticoagulant options include low molecular weight heparin, unfractionated heparin, and fondaparinux. In APS patients, lupus anticoagulant can affect phospholipid-dependent coagulation monitoring tests, so that they may not reflect true anticoagulation intensity. Accurate assessment of anticoagulation intensity is essential, to optimize anticoagulant dosing and facilitate thrombus resolution; minimize the risk of recurrent thrombosis or bleeding; inform assessment of whether recurrent thrombosis is related to breakthrough thrombosis while on therapeutic anticoagulation, subtherapeutic anticoagulation, non-adherence, or spurious results; and guide the management of bleeding. Knowledge of anticoagulant intensity also informs assessment and comparison of anticoagulation regimens in clinical studies. Considerations regarding anticoagulation dosing and/or monitoring of thrombotic APS patients underpin appropriate management in special situations, notably APS-related severe renal impairment, which can occur in APS or APS/systemic lupus erythematosus-related nephropathy or catastrophic APS; and APS-related thrombocytopenia. Anticoagulant dosing and monitoring in thrombotic APS patients also require consideration in anticoagulant-refractory APS and during pregnancy. In this review, we summarize the tests generally used in monitoring anticoagulant therapy, use of the main anticoagulants considered for thrombotic APS, lupus anticoagulant effects on anticoagulation monitoring tests, and strategies for appropriate anticoagulant monitoring in thrombotic APS.