Background: Reagent‐supported thromboelastometry with the rotation thrombelastography (e.g. ROTEM®) is a whole blood assay that evaluates the visco‐elastic properties during blood clot formation and ...clot lysis. A hemostatic monitor capable of rapid and accurate detection of clinical coagulopathy within the resuscitation room could improve management of bleeding after trauma. Objectives: The goals of this study were to establish whether ROTEM correlated with standard coagulation parameters to rapidly detect bleeding disorders and whether it can help to guide transfusion. Methods: Ninety trauma patients were included in the study. At admission, standard coagulation assays were performed and ROTEM parameters such as clot formation time (CFT) and clot amplitude (CA) were obtained at 15 min (CA15) with two activated tests (INTEM, EXTEM) and at 10 min (CA10) with a test analyzing specifically the fibrin component of coagulation (FIBTEM). Results: Trauma induced significant modifications of coagulation as assessed by standard assays and ROTEM. A significant correlation was found between prothrombin time (PT) and CA15‐EXTEM (r = 0.66, P < 0.0001), between activated partial thromboplastin time and CFT‐INTEM (r = 0.91, P < 0.0001), between fibrinogen level and CA10‐FIBTEM (r = 0.85, P < 0.0001), and between platelet count and CA15‐INTEM (r = 0.57, P < 0.0001). A cutoff value of CA15‐EXTEM at 32 mm and CA10‐FIBTEM at 5 mm presented a good sensitivity (87% and 91%) and specificity (100% and 85%) to detect a PT > 1.5 of control value and a fibrinogen less than 1 g L−1, respectively. Conclusions: ROTEM is a point‐of‐care device that rapidly detects systemic changes of in vivo coagulation in trauma patients, and it might be a helpful device in guiding transfusion.
Blood loss and uncontrollable bleeding are major factors affecting survival in trauma patients. Because treatment with antifibrinolytic drugs may be effective, early detection of hyperfibrinolysis ...with rotation thrombelastography (ROTEM®) may be beneficial.
Eighty-seven trauma patients were included in this prospective observational study. Blood samples were collected at admission. After in vitro activation with tissue factor (EXTEM) and inhibition with aprotinin (APTEM), ROTEM® parameters including maximal clot firmness (MCF) and clot lysis index at 30 min (CLI30) were determined. Hyperfibrinolysis was defined as a euglobulin lysis time (ELT) <90 min. Threshold for ROTEM® parameters were determined with receiver-operating characteristic curves (ROC) analysis according to the ELT results.
ELT was determined in a subgroup of 23 patients. In this group of patients, ROC analysis showed that for a threshold of 18 mm (MCF-EXTEM), 71% (CLI30) and 7% (increase of MCF-APTEM), sensitivity was, respectively, 100%, 75%, and 80% with a specificity of 100%. With the application of these thresholds to the whole trauma cohort, ROTEM® analysis detected hyperfibrinolysis in five patients 6%, 95% confidence interval (CI): 2–13%. As expected, patients with hyperfibrinolysis were more severely injured (median Injury Severity Score: 75 vs 20, P<0.05), had greater coagulation abnormalities international normalized ratio (INR): 8.2 vs 1.3, P<0.05; fibrinogen: 0.0 vs 2.2 g litre−1, P<0.05, and a higher mortality rate (100%, CI: 48–100% vs 11% CI: 5–20%, P<0.05).
ROTEM® provided rapid and accurate detection of hyperfibrinolysis in severely injured trauma patients.
La coagulopathie post-traumatique est fréquente et complexe, elle aggrave le pronostic des traumatisés. Son diagnostic repose sur la biologie standard mais récemment des techniques de biologie ...déportée permettant l’obtention rapide d’un INR ou d’une étude de la formation du caillot par thromboélastométrie, ont permis d’obtenir des informations plus précoces. Le traitement de la coagulopathie doit être entrepris le plus précocement possible. Deux stratégies sont possibles avec soit l’utilisation d’une association de CGR/plaquette/PFC selon un ratio défini, soit l’utilisation de concentrés de facteurs guidés par la thromboélastométrie. À la correction de la coagulopathie doit impérativement s’associer le traitement des facteurs favorisants tels que l’hypothermie, l’acidose et l’hypocalcémie.
Trauma-induced coagulopathy is frequent and complex, and is responsible for an impairment of trauma outcome. Diagnosis of trauma coagulopathy is usually done with standard biology but recently new technics arose and gave us the opportunity to have faster information on coagulopathy with quick INR measure or clot formation study with thrombelastometry. Treatment of the coagulopathy should be done earlier in the course of trauma. Two strategies are possible that include either the association of RBC, platelet and FFP in a predefined ratio, or the use of factor concentrates guided with thrombelastometry. Treatment of favouring factors such as hypothermia, acidosis and hypocalcemia is also mandatory.
Essentials
Pregnancy is a risk factor for thrombosis.
Management of thrombosis risk in pregnancy remains a challenge.
Prophylaxis needs to be personalized.
Our score may be a helpful tool for the ...management of pregnancies at high risk of thrombosis.
Summary
Background
Patients with thrombophilia and/or a history of venous thromboembolism (VTE) are at risk of thrombosis during pregnancy. A risk score for pregnancies with an increased risk of VTE was previously described by our group (Lyon VTE score).
Objectives
The aim of this prospective study was to assess the efficacy and safety of our score‐based prophylaxis strategy in 542 pregnancies managed between 2005 and 2015 in Lyon University Hospitals.
Patients/Methods
Of 445 patients included in the study, 36 had several pregnancies during the study period. Among these 445 patients, 279 had a personal history of VTE (62.7%), 299 patients (67.2%) had a thrombophilia marker, and 131 (29.4%) thrombophilic women had a personal history of VTE. During pregnancy, patients were assigned to one of three prophylaxis strategies according to the risk scoring system.
Results
In the antepartum period, low molecular weight heparin (LMWH) prophylaxis was prescribed to 64.5% of patients at high risk of VTE. Among them, 34.4% were treated in the third trimester only, and 30.1% were treated throughout pregnancy. During the postpartum period, all patients received LMWH for at least 6 weeks. Two antepartum‐related VTEs (0.37%; one with a score of < 3 and the other with a score of > 6) and four postpartum‐related VTEs (0.73%; three with scores of 3–5 and one with a score of > 6) occurred. No case of pulmonary embolism was observed during the study period. The rate of bleeding was 0.37%. No serious bleeding requiring transfusions or surgery occurred during the study period.
Conclusion
The use of a risk score may provide a rational decision process to implement safe and effective antepartum thromboprophylaxis in pregnant women at high risk of VTE.
Introduction
The correct diagnosis and classification of VWD (von Willebrand disease) is crucial and must be optimized by including the collagen binding assay (VWF:CB). VWF:CB remains an ...under‐recognized tool, not fully automated. The objective of this study was to evaluate and to compare the previously evaluated automated chemiluminescent assay (HemosIL AcuStar VWF:CB) to the ELISA ASSERACHROM® assay used routinely in our laboratory in patients with molecular diagnosis of VWD.
Methods
A plasma sample from 49 patients previously diagnosed with VWD (type 1; type 2A, type 2M, type 2B) through phenotype and VWF (von Willebrand factor) analysis and 15 healthy controls was analysed. The VWF ristocetin cofactor activity (VWF:Rco) and VWF antigen (VWF:Ag) were performed simultaneously on the VWD plasma samples, and VWF:CB/VWF:Ag ratios were calculated.
Results
The AcuStar VWF:CB assay was quickly performed with Pearson's correlation coefficient (r²) of .9571 between assays and a bias of +5.1U/dL (AcuStar > ELISA). Discrepancies of VWF:CB/VWF:Ag ratio were observed in type 2M‐2A‐like VWD (ratio <0.6 with AcuStar assay in 4/5 samples).
Conclusion
The AcuStar VWF:CB assay has demonstrated good performance to detect VWF mutational changes with capacity to discriminate quickly principal types of VWD.
Introduction
Haemostatic assessments of patients with von Willebrand disease (VWD) who undergo total knee arthroplasty (TKA) and total hip arthroplasty (THA) have mainly relied on subjective ...parameters.
Aims
To compare objective haemostatic outcomes of TKA/THA in VWD patients and controls without bleeding disorders.
Methods
We retrospectively analysed haemostatic outcomes in VWD patients undergoing TKA/THA from 1993 to 2011 and compared them with two matched controls per operation. Using one‐way analysis of variance, we tested the effect of VWD on bleeding risk after TKA and THA.
Results
Twelve VWD patients (6 type 1, 3 type 2M, 1 each of types 2A/2B/3) undergoing 19 operations (12 TKA, 7 THA) were matched to 38 controls. One (5%) of 19 operations in VWD patients and none of the control operations met clinical criteria for major bleeding. Baseline and postoperative day 1 haemoglobin levels, postoperative blood loss, transfused red blood cells (RBCs) and mean hospitalization days were not significantly different. More VWD patients than controls received RBC transfusions 12 (63%) vs. 12 (32%). Only 9 (47%) VWD patients vs. 38 (100%) controls received pharmacologic VTE prophylaxis. No postoperative symptomatic VTE occurred in either group.
Conclusion
In this largest, single‐institutional study, von Willebrand factor replacement based on daily levels resulted in low frequency of major bleeding in VWD patients after TKA/THA. RBC transfusion was more frequent compared with matched controls, but other objective measures of haemostasis were similar. Lack of sufficient details in published reports precluded comparison of haemostatic outcomes.
Patients with congenital afibrinogenemia suffer from spontaneous recurrent severe bleeding. While fibrinogen concentrates are known to effectively treat bleeding episodes, thrombotic complications ...often occur upon replacement therapy, rendering clinical management highly challenging.
We hereby report a case of combined afibrinogenemia and congenital antithrombin deficiency manifested by recurrent life-threatening bleeding, as well as spontaneous severe arterial occlusion, such as acute coronary syndrome and stroke, and venous thromboses like pulmonary embolism.Secondary fibrinogen prophylaxis is recommended following any initial life-threatening bleeding episode in patients with afibrinogenemia, yet the high associated risk of thrombosis illustrates the complexity of choosing the most effective prophylaxis strategy combining fibrinogen concentrate with antithrombotic agent for optimal protection against the risk of both severe bleeding and thrombosis. For our patient, the thrombin generation assay objectively confirmed her prothrombotic tendency.
This case may help us better understand the pathophysiology of arterial thrombosis in afibrinogenemia, while highlighting the difficulty of managing such complications.
Factor XI (FXI) deficiency is a rare bleeding disorder. Most patients with FXI deficiency are mild bleeders but certain patients with similar FXI activity exhibit different bleeding phenotype. ...Routine laboratory assays do not help physicians to estimate the individual bleeding risk in these patients. Thrombin generation test (TGT) is a more comprehensive, global function test of the clotting system. We investigated whether or not the bleeding tendency of patients with FXI deficiency is correlated with features of the TGT. Twenty‐four patients with FXI deficiency were divided in two groups: (i) severe bleeders (n = 9) and (ii) mild or non‐bleeders (n = 15). All severe bleeders had a personal history of surgery‐related severe bleeding. Thrombin generation (TG) was measured in platelet‐rich plasma (PRP) using a low concentration of tissue factor 0.5 pm. In patients exhibiting severe bleeding tendency, independently of their FXI level, a dramatically impaired TG was observed. For example, despite a low plasma FXI = 1 IU dl−1, a clinically non‐bleeding individual exhibited normal TG results whereas another patient with severe bleeding history and FXI = 40 IU dl–1 had a very low TG capacity. Low velocity and delayed TG were the main parameters suggesting a higher bleeding risk. DNA analysis of patients reported eight novel mutations of the FXI gene but neither mutation location nor secretion or not of the variant correlated with the bleeding tendency. The results of this study suggest that TG measurement in PRP may be a useful tool to predict bleeding risk in FXI deficiency and should be studied further in larger prospective clinical studies.
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