Marijuana may lead to increased platelet activity in trauma patients.

INTRODUCTION: Delta-9-tetraydrocannabinol (THC) usage is associated with venous thromboembolic events (VTE) in trauma patients. We hypothesized that THC â€‹+ â€‹trauma patients would have less platelet inhibition than THC - patients using thromboelastography with platelet mapping (TEG-PM). METHODS: Results from initial TEG- PM assays and patient's UDS were reviewed between 2019 and 2023. Mean levels of arachidonic acid (AA) and adenosine diphosphate (ADP) percent inhibition were compared by THC status. RESULTS: 793 patients had TEG-PM and UDS data. Mean levels of arachidonic acid (AA) percentage inhibition were 32.6 â€‹± â€‹34.2. AA inhibition was lower for THC â€‹+ â€‹vs THC- patients (THC+ 23.9 â€‹± â€‹27.0 vs THC- 34.3 â€‹± â€‹35.3, P â€‹< â€‹0.001). There was no association between THC status and ADP inhibition (THC+ 32.5 â€‹± â€‹27.1 vs THC- 30.8 â€‹± â€‹28.4, P â€‹= â€‹0.536). DISCUSSION: To our knowledge, our data are the first to suggest a clinically measurable increase in platelet reactivity in THC â€‹+ â€‹trauma patients. More work is needed to determine if addition of aspirin to the chemoprophylaxis strategy for THC â€‹+ â€‹patients would mitigate the known association of THC with VTE.

In vitro protamine addition for coagulation assessment using TEG 6s system during cardiopulmonary bypass: a pilot study.

OBJECTIVE: Systemic heparinization during cardiopulmonary bypass (CPB) can significantly affect thromboelastography (TEG). This study investigated the feasibility of adding protamine in vitro to allow assessment of coagulation status using the TEG 6s system during CPB. METHODS: In this prospective observational study, 21 patients undergoing elective cardiac valve surgery were evaluated. During CPB, protamine was added in vitro to the heparinized blood of these patients at a concentration of 0.05 mg/mL and analyzed with the TEG 6s (Pre). The TEG parameters were compared to those analyzed after CPB withdrawal and systemic protamine administration (Post). RESULTS: The citrated kaolin maximal amplitude (CK-MA) and the citrated functional fibrinogen maximal amplitude (CFF-MA) exhibited strong correlations between Pre and Post measurements (r = 0.790 and 0.974, respectively, P < 0.001 for both), despite significant mean differences (-2.23 mm for CK-MA and -0.68 mm for CFF-MA). Bland-Altman analysis showed a clinically acceptable agreement between Pre and Post measurement of CK-MA and CFF-MA (the percentage error was 10.6% and 12.2%, respectively). In contrast, the citrated kaolin reaction time (CK-R) showed no significant correlation between Pre and Post measurements (r = 0.328, P = 0.146), with a mean difference of 1.42 min (95% CI: -0.45 to 3.29). CONCLUSIONS: In vitro protamine addition allows assessment of coagulation status during CPB using the TEG 6s system. CK-MA and CFF-MA measured during CPB using this method revealed a strong correlation and agreement with post-CPB measurements, suggesting that our method potentially facilitates early prediction of post-CPB coagulation status and decision-making on transfusion strategies. CLINICAL TRIAL REGISTRATION: The study was registered in the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR, registration number: UMIN000041097, date of registration: July 13, 2020, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000046925 ) before the recruitment of participants.

Thromboelastography in acute immunologic reactions: a prospective pilot study.

Background: Biomarkers of fibrinolysis are elevated during acute immunologic reactions (allergic reactions and angioedema), although it is unclear whether fibrinolysis is associated with disease severity. Objectives: We investigated a possible association between maximum lysis (ML) measured by thromboelastography and the severity of acute immunologic reactions. Methods: We recruited patients with acute immunologic reactions at a high-volume emergency department. Clinical disease severity at presentation and at the end of the emergency department stay was assessed using a 5-grade scale, ranging from local symptoms to cardiac arrest. We determined ML on admission by thromboelastography (ROTEM's extrinsic [EXTEM], and aprotinin [APTEM] tests), expressed as ML%. Hyperfibrinolysis was defined as an ML of >15% in EXTEM, which was reversed by adding aprotinin (APTEM). We used exact logistic regression to investigate an association between ML% and disease severity (grades 1 and 2 [mild] vs 3-5 [severe]) and between hyperfibrinolysis and disease severity. Results: We included 31 patients (71% female; median age, 52 [IQR, 35-58] years; 10 [32%] with a severe reaction). ML% was higher in patients with severe symptoms (21 [IQR, 12-100] vs 10 [IQR, 4-17]). Logistic regression found a significant association between ML% and symptom severity (odds ratio, 1.07; 95% CI, 1.01-1.21; P = .003). Hyperfibrinolysis was detected in 6 patients and found to be associated with severe symptoms (odds ratio, 17.59; 95% CI, 1.52-991.09; P = .02). D-dimer, tryptase, and immunoglobulin E concentrations increased with the severity of immunologic reactions. Conclusion: ML, quantified by thromboelastography, is associated with the severity of acute immunologic reactions.

Utility of thromboelastography with platelet mapping (TEG-PM) for monitoring platelet transfusion in qualitative platelet disorders.

BACKGROUND: Patients with pathogenic variants in RASGRP2 (inherited platelet disorder (IPD)-18) have normal platelet counts but show impaired platelet aggregation due to diminished activation of αIIbß3 integrin. This defect results in moderate to severe bleeding episodes, especially following surgical procedures, which require patients to be transfused with platelets and/or pro-hemostatic agents. We recently demonstrated that hemostatic efficacy of transfused platelets is limited by dysfunctional endogenous platelets in a mouse model of IPD-18 (Rasgrp2-/- mice), as dysfunctional platelets were recruited to the forming hemostatic plug but did not participate in clot contraction. Consequently, higher amounts of transfused platelets were required to outcompete these dysfunctional cells and to reverse bleeding. OBJECTIVE: We here studied the usefulness of thromboelastography with platelet mapping (TEG-PM), a method to evaluate platelet-dependent clot contraction, for ex vivo monitoring of the hemostatic potential in Rasgrp2-/- mice transfused with various amounts of wild-type (WT) platelets. RESULTS: Rasgrp2-/- whole blood samples did not contract in TEG-PM, consistent with a critical role of this protein in αIIbß3 activation. Addition of WT platelets improved TEG parameters (K time, α-angle, MA) in a ratio dependent manner, consistent with our recent in vivo studies showing impaired hemostasis at a 5:1, but not at a 2:1 ratio of mutant to WT platelets. K and α values were identified as better predictors of transfusion efficacy than MA, the most platelet-dependent TEG parameter. CONCLUSION: This proof-of-concept study supports the use of TEG-PM to monitor platelet transfusion ratios and hemostatic potential in IPD-18 and potentially other platelet disorders.

Rotational thromboelastometry predicts future bleeding events in patients with cirrhosis.

BACKGROUND AND AIMS: Patients with cirrhosis of the liver are in a delicate state of rebalanced haemostasis and are at risk of developing both bleeding and thrombotic complications. Conventional haemostatic tests are unable to predict bleeding and thrombosis in these patients. We aimed to explore the role of Rotational Thromboelastometry (ROTEM) in predicting bleeding and thrombotic events in patients with cirrhosis. METHODS: We conducted a prospective cohort study of patients with cirrhosis at two metropolitan hospitals. All patients underwent ROTEM analysis and were then followed to record any bleeding and thrombotic events. Univariate and multivariate logistic regression analyses were performed to explore associations with bleeding and thrombotic events. RESULTS: Nineteen of the 162 patients recruited experienced a bleeding event within one year of ROTEM analysis. On univariate analysis, maximum clot firmness (MCF) using both EXTEM and INTEM tests was significantly reduced in patients who had a bleeding event, compared to those who did not (50 mm vs. 57 mm, p < 0.01 and 48 mm vs. 54 mm, p < 0.01, respectively). In addition, on univariate analysis, clotting time (CT) in the INTEM test was prolonged in the bleeding group (214 s vs. 198 s, p = 0.01). On multivariate analysis, only MCFEX was a significant predictor of bleeding events. In contrast, there was no association found between ROTEM parameters and development of thrombosis within a one-year period. CONCLUSIONS: ROTEM may provide a useful tool in predicting future bleeding events in patients with cirrhosis. Larger studies are required to further validate this finding and explore its application in clinical practice.

Impact of coagulopathy assessment with thromboelastography and thromboelastometry on transfusion requirements in critically ill cirrhosis with nonvariceal bleeding: A prospective observational study.

Background: Viscoelastic tests are now routinely used for coagulopathy correction in patients with cirrhosis. Thromboelastography (TEG®) and rotational thromboelastometry (RoTEM®) are the most widely studied tests in this population. However, they have not been compared with each other in critically ill patients with liver disease presenting with nonvariceal bleed. Hence, we aimed to compare these tests for coagulopathy correction in patients with liver disease presenting with nonvariceal bleeding. Methods: Sixty adult patients with liver cirrhosis presented to the liver intensive care unit, presenting with a nonvariceal upper gastrointestinal (GI) bleed (diagnosed by doing upper GI endoscopy which revealed bleeding from a nonvariceal source) oral or nasal bleed were enrolled. The patients were allocated to the TEG® group (Group T) or RoTEM® group (Group R) depending on the immediate availability of the viscoelastic test. Coagulopathy correction was done in each group as per established protocols and the results were compared. Results: There was a significant difference in the fresh frozen plasma (FFP) transfusion between the groups. The TEG® group received more FFP when compared to the RoTEM® group (P = 0.001). Conclusion: RoTEM®-based coagulopathy correction leads to lesser use of blood products with similar control of bleeding when compared to TEG, in critically ill patients with cirrhosis.

Andexanet Alfa for Edoxaban Reversal and Associated Thromboelastography Changes in Surgical Pulmonary Embolectomy.

Andexanet alfa neutralizes factor Xa inhibitors in critical bleeding situations. However, in cardiac surgery with cardiopulmonary bypass (CPB), heparin resistance induced by andexanet alfa should be a concern, and the lack of point-of-care monitoring of plasma concentration of factor Xa inhibitors makes it difficult to decide when to administer andexanet alfa. A 69-year-old man underwent emergency surgery for acute pulmonary thromboembolism. The patient had been on edoxaban until the day before the surgery. Withdrawal from CPB required venoarterial extracorporeal membrane oxygenation due to right heart failure, followed by severe bleeding that required massive transfusion. Despite adequate coagulation factor replacement, bleeding persisted and citrated kaolin-reaction time (CK-R) on thromboelastography (TEG) was prolonged. Administering andexanet alfa achieved excellent hemostasis without any thrombosis and normalized the prolonged CK-R of TEG. This is the first report of a change in TEG findings before and after administration of andexanet alfa in a cardiac surgery patient taking factor Xa inhibitor. Monitoring CK-R in TEG may help evaluate the anticoagulant effect of factor Xa inhibitors and the reversal effect of andexanet alfa.

Prothrombin and activated partial thromboplastin times, thromboelastography, hematocrit, and platelet count in a feline hemorrhage/over-resuscitation model using lactated Ringer's solution or 6% tetrastarch 130/0.4.

OBJECTIVE: To describe and compare prothrombin time (PT), activated partial thromboplastin time (aPTT), thromboelastography (TEG), HCT, and platelet count measurements in a hemorrhage/over-resuscitation model. DESIGN: Randomized crossover study. SETTING: University teaching hospital. ANIMALS: Six cats. INTERVENTIONS: Anesthetized cats underwent 3 treatments at 2-month intervals. The treatments were as follows: NHR-no controlled hemorrhage and sham resuscitation; LRS-controlled hemorrhage and lactated Ringer's solution (LRS) for resuscitation; and Voluven-controlled hemorrhage and 6% tetrastarch 130/0.4 for resuscitation. The LRS and Voluven were administered at 60 and 20 mL/kg/h, respectively, for 120 minutes. Blood samples were drawn for PT, aPTT, TEG, HCT, and platelet count measurements at a healthy check (T - 7d), after controlled hemorrhage (T0), at 60 and 120 minutes of resuscitation (T60 and T120), and at 24 hours after completion of resuscitation (T24h). Data were analyzed using a general linear mixed model approach (significance was P < 0.05). MEASUREMENTS AND MAIN RESULTS: Total median blood loss (controlled hemorrhage and blood sampling from T0 to T120) at T120 was 11.4, 31.0, and 30.8 mL/kg for NHR, LRS, and Voluven, respectively. PT and aPTT during LRS and Voluven were prolonged at T60 and T120 compared to NHR (P < 0.001). On TEG, the reaction time, kinetic time, and alpha-angle were within reference intervals for cats at all time points in all treatments, while maximum amplitude was less than the reference interval (40 mm) at T0, T60, and T120 during Voluven and at T60 and T120 during LRS compared to NHR (both P < 0.001). The HCT and platelet count were significantly lower at T60 and T120 during LRS and Voluven compared to NHR (P < 0.001). CONCLUSIONS: Hypocoagulopathy was observed during hemorrhage and liberal fluid resuscitation. Prolongation of PT and aPPT and decreased clot strength may have been caused by hemodilution and platelet loss.

Perioperative ROTEM® evaluation in a patient affected by severe VII factor deficiency undergoing microvascular decompression craniotomy for hemifacial spasm.

The potential use of TEG/ROTEM® in evaluating the bleeding risk for rare coagulation disorders needs to be assessed, considering the common mismatch among laboratory tests and the clinical manifestations. As a result, there is currently no published data on the use of viscoelastic tests to assess coagulation in FVII deficient patients undergoing elective neurosurgery. We describe the case of a patient affected by severe FVII deficiency who underwent microvascular decompression (MVD) craniotomy for hemifacial spasm (HFS). The ROTEM® did not show a significant coagulopathy according to the normal ranges, before and after the preoperative administration of the recombinant activated FVII, but a substantial reduction in EXTEM and FIBTEM Clotting Times was noted. The values of coagulation in standard tests, on the contrary, were indicative of a coagulopathy, which was corrected by the administration of replacement therapy. Whether this difference between ROTEM® and standard tests is due to the inadequacy of thromboelastographic normal ranges in this setting, or to the absence of clinically significant coagulopathy, has yet to be clarified. Neurosurgery is a typical high bleeding risk surgery; additional data is required to clarify the potential role for thromboelastographic tests in the perioperative evaluation of the FVII deficient neurosurgical patients.

Temperature effect on coagulation function in mild hypothermic patients undergoing thoracic surgeries: thromboelastography (TEG) versus standard tests.

PURPOSE: Our previous research has revealed that mild hypothermia leads to excessive bleeding in thoracic surgeries, while the underlying mechanism stayed unrevealed by the standard coagulation tests. The research question in this study was as follows: "How does mild hypothermia impair the hemostatic function in patients receiving thoracic surgeries?". The purpose was to detect the disturbed coagulation processes by comparing the TEG parameters in patients receiving active vs. passive warming during thoracic surgeries. METHODS: Standard coagulation tests and thromboelastography (TEG) were adopted to compare the hemostatic functions in patients receiving active vs. passive warming during thoracic surgeries. Furthermore, blood samples from passive warming group were retested for TEG at actual core body temperatures. RESULTS: Sixty-four eligible patients were included in this study. TEG revealed that mild hypothermia significantly disturbed coagulation by decreasing MA (59.4 ± 4.5 mm vs. 64.2 ± 5.7 mm, p = 0.04) and α angle (70.4 ± 5.2° vs. 74.9 ± 4.4°, p = 0.05) and prolonging ACT (122.2 ± 19.3 s vs. 117.3 ± 15.2 s, p = 0.01) and K time (1.9 ± 1.0 s vs. 1.3 ± 0.4 min, p = 0.02). TEGs conducted under core body temperatures revealed more impaired coagulation than those incubated at 37 °C. Furthermore, postoperative shivering and waking time were significantly increased in mild hypothermic patients. CONCLUSION: Mild hypothermia significantly impaired coagulation function in patients receiving thoracic surgeries, which could be detected by TEGs other than the standard coagulation tests. Temperature-adjusted TEGs may provide a preferable method of hemostatic monitoring and transfusion guidance in thoracic surgeries, which warrants further clinical investigations.

Viscoelastic blood coagulation testing system enabled by a non-contact triboelectric angle sensor.

Thromboelastography (TEG) remains a convenient and effective viscoelastic blood coagulation testing device for guiding blood component transfusion and assessing the risk of thrombosis. Here, a TEG enabled by a non-contact triboelectric angle sensor (NTAS) with a small size (∼7 cm3) is developed for assessing the blood coagulation system. With the assistance of a superelastic torsion wire structure, the NTAS-TEG realizes the detection of blood viscoelasticity. Benefiting from a grating and convex design, the NTAS holds a collection of compelling features, including accurate detection of rotation angles from -2.5° to 2.5°, high linearity (R 2 = 0.999), and a resolution of 0.01°. Besides, the NTAS exhibits merits of low cost and simplified fabrication. Based on the NTAS-TEG, a viscoelastic blood coagulation detection and analysis system is successfully constructed, which can provide a graph and parameters associated with clot initiation, formation, and stability for clinicians by using 0.36 mL of whole blood. The system not only validates the feasibility of the triboelectric coagulation testing sensor, but also further expands the application of triboelectric sensors in healthcare.

Association of clopidogrel resistance and ABCD-GENE score with long-term clinical prognosis in patients with ischemic stroke or TIA.

BACKGROUND: Clopidogrel resistance (CR) is associated with adverse clinical outcomes in acute ischemic stroke or transient ischemic attack (TIA) patients. However, whether CR affects the long-term clinical prognosis remains to be clarified. The ABCD-GENE score is a novel risk model that identifies CR in cardiovascular disease patients; its diagnostic ability and application in ischemic stroke or TIA remain to be studied. This study aimed to investigate the diagnostic ability of the ABCD-GENE score for CR and analyze the relationship between CR and long-term clinical prognosis in patients with ischemic stroke or TIA. METHODS: From January 2018 to January 2021, 251 ischemic stroke or TIA patients who were treated with clopidogrel for more than three months after onset and maintained the medication until the follow-up time were enrolled, and platelet reactivity was detected by thromboelastography. CYP2C19 gene analysis was performed. Adverse clinical outcomes were recorded from 3months after onset. The median follow-up time was 878days. RESULTS: The prevalence of CR was 33.9%. The proportion of CYP2C19 loss-of-function carriers was 62.2%. The ABCD-GENE score≥10 was independently associated with CR (OR=1.82, 95% CI: 1.02-3.24, P=0.041), and the C-statistic value of the score (as a binary and integer variable) on CR was 0.58 and 0.63, respectively. The risk of long-term adverse clinical outcomes was not significantly different between CR and clopidogrel sensitive groups (12.94% vs. 11.44%, HR=1.22, 95% CI: 0.57-2.62, P=0.603). A similar result was observed between ABCD-GENE score≥10 and ABCD-GENE score<10 groups (10.38% vs. 12.64%, HR=1.19, 95% CI: 0.55-2.60, P=0.666). CONCLUSIONS: In ischemic stroke or TIA patients, the ABCD-GENE score could identify the risk of CR. CR was not associated with long-term adverse clinical outcomes.

Hypocoagulability in severe yellow fever infection is associated with bleeding: results from a cohort study.

Background: Severe yellow fever infection (YFI) may be complicated by a hemorrhagic diathesis. However, the hemostasis profile of YFI has rarely been reported. Objectives: The aim of this study was to characterize the hemostatic features of YFI by using a rotational thromboelastometry (ROTEM). Methods: We evaluated clinical, laboratory, and ROTEM parameters in adults with severe YFI and their correlation with hemostatic variables according to bleeding and death. Results: A total of 35 patients were included (median age, 49 years). ROTEM was performed in 22 patients, of whom 21 (96%) presented bleeding and 4 (18%) died. All patients who died had major bleeding. Patients who died presented prolonged clotting time (CT; median, 2326 seconds; IQR, 1898-2986 seconds) and reduced alpha angle (median, 12°; IQR, 12°-15°) in comparison with patients who had minor (median CT, 644 seconds; IQR, 552-845 seconds and alpha angle, 47°; IQR, 28°-65°) and major (median CT, 719 seconds; IQR, 368-1114 seconds and alpha angle, 43°; IQR, 32°-64°) bleeding who survived. In patients who had bleeding, CT showed a strong negative correlation with factor (F)V (r = -.68), FIX (r = -.84), and FX (r = -.63) as well as alpha angle showed a strong negative correlation with FIX (r = -.92). In patients who died, the correlations were even stronger. A total of 19/21 (90%) patients presented hypocoagulability assessed by ROTEM. Conclusion: Hypocoagulabitity is the hallmark of the bleeding diathesis of severe YFI. Abnormal CT and alpha angle associated with death and could be used as potential predictors of adverse outcome in severe YFI.

Temporal dynamics of in vitro hemostatic function in platelets cryopreserved using a novel approach for rapid issuance.

BACKGROUND: Current procedures for thawing and issuing of cryopreserved platelets (CPPs) are laborious and have remained challenging in emergency settings such as blood banks and military operations. In this prospective study, a novel processing method designed to facilitate the rapid issuance of CPPs with no postthaw handling required was developed and functionally characterized in parallel with standard CPPs manufactured. STUDY DESIGN AND METHODS: Double-dose plateletpheresis units (n = 42) were cryopreserved at -80°C in 5%-6% dimethyl sulfoxide to produce matched pairs thawed successively over a 27-month period for comparison between two processing arms. In contrast to the standard CPPs manufactured as standalone units, platelets were frozen in tandem with resuspending plasma in a distinct partition as a single unit in the novel method, herein referred to as tandem CPPs. Postthaw (PT) CPPs from both arms were assessed at PT0-, 12-, and 24-h to measure platelet recovery, R-time (time to clot initiation; min), and maximum amplitude (MA; clot strength; mm) using thromboelastography. RESULTS: In the overall dataset, mean platelet recovery was higher (p < .0005) for tandem CPPs (83.9%) compared with standard CPPs (73.3%) at PT0; mean R-times were faster (p < .0005) for tandem CPPs (2.5-3.6 min) compared with standard CPPs (3.0-3.8 min); mean MA was higher for tandem CPPs (57.8-59.5 mm) compared with standard CPPs (52.1-55.8 mm) at each postthaw time point (p < .05). CONCLUSION: Robust temporal dynamics of superior hemostatic functionality were established for tandem CPPs over extended cryopreservation up to 27 months and 24 h of postthaw storage.

Use of Thromboelastography in Coronary Artery Bypass Grafting in a Patient With Factor â ¤ Deficiency With Platelet Function Disorders: A Case Report and Literature Review.

Reports on cases of factor Ⅴ (FⅤ) deficiency complicated by platelet function disorders in patients undergoing cardiac surgery are rare, and the utilization of thromboelastography in such cases is limited. This case presents a unique case of FⅤ deficiency complicated by platelet function disorders, highlighting the significance of tailored transfusion strategies guided by thromboelastography (TEG). A 64-year-old hemodialysis patient who was diagnosed with FⅤ deficiency 24 years prior presented for an on-pump coronary artery bypass graft. The decrease in FⅤ activity on preoperative examination was mild. Based on this finding, it was determined that preoperative fresh frozen plasma supplementation was not required. However, the case was complicated by platelet function disorders; therefore, a preoperative transfusion of platelet concentrate was performed to correct the decreased platelet function, enabling subsequent surgery. Intraoperative and postoperative transfusion strategies were guided by TEG. This study highlights TEG-guided transfusion management as a viable option for patients with FⅤ deficiency complicated by platelet function disorders.

Point of care guided coagulation management in adult patients on ECMO: A systematic review and meta-analysis.

BACKGROUND: Despite the advancements in extracorporeal membrane oxygenation (ECMO) technology, balancing the prevention of thrombosis and the risk of bleeding in patients on ECMO is still a significant challenge for physicians. This systematic review and meta-analysis aimed to assess the efficacy and safety of viscoelastic point-of-care (POC)-guided coagulation management in adult patients on ECMO. METHODS: PubMed Medline, Embase, Scopus, Web of Science, and Cochrane Library databases were searched. After quality assessment, meta-analysis was carried out using random effects model, heterogeneity using I2 and publication bias using Doi and Funnel plots. RESULTS: A total of 1718 records were retrieved from the searches. Fifteen studies that enrolled a total of 583 participants met the inclusion criteria. Of those, 3 studies enrolling 181 subjects were eligible for meta-analysis. In patients managed with POC-guided algorithms, the odds were coherently lower for bleeding (OR 0.71, 95%CI 0.36-1.42), thrombosis (OR 0.91, 95%CI 0.32-2.60), and in-hospital mortality (OR 0.54, 95%CI 0.29-1.03), but not for circuit change or failure (OR 1.50, 95%CI 0.59-3.83). However, the differences were not statistically significant due to wide 95%CIs. CONCLUSION: Viscoelastic POC monitoring demonstrates potential benefits for coagulation management in ECMO patients. Future research should focus on standardizing evidence to improve clinical decision-making. REGISTRATION: The protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) with registration ID CRD42023486294.

Comparative studies between humans and golden Syrian hamsters via thromboelastography.

BACKGROUND: Thromboelastography (TEG) is a widely utilized clinical testing method for real-time monitoring of platelet function and the thrombosis process. Lipid metabolism disorders are crucial risk factors for thrombosis. The lipid metabolism characteristics of hamsters resemble those of humans more closely than mice and rats, and their relatively large blood volume makes them suitable for studying the mechanisms of thrombosis related to plasma lipid mechanisms. Whole blood samples from golden Syrian hamsters and healthy humans were obtained following standard clinical procedures. TEG was employed to evaluate coagulation factor function, fibrinogen (Fib) function, platelet function, and the fibrinolytic system. METHODS: The whole blood from hamster or healthy human was isolated following the clinical procedure, and TEG was employed to evaluate the coagulation factor function, Fib function, platelet function, and fibrinolytic system. Coagulation analysis used ACLTOP750 automatic coagulation analysis pipeline. Blood routine testing used XN-2000 automatic blood analyzer. RESULTS: TEG parameters revealed that hamsters exhibited stronger coagulation factor function than humans (reaction time [R], p = 0.0117), with stronger Fib function (alpha angle, p < 0.0001; K-time [K], p < 0.0001). Platelet function did not differ significantly (maximum amplitude [MA], p = 0.077). Hamsters displayed higher coagulation status than humans (coagulation index [CI], p = 0.0023), and the rate of blood clot dissolution in hamsters differed from that in humans (percentage lysis 30 min after MA, p = 0.02). Coagulation analysis parameters indicated that prothrombin time (PT) and activated partial thromboplastin time (APTT) were faster in hamsters than in humans (PT, p = 0.0014; APTT, p = 0.03), whereas the Fib content was significantly lower in hamsters than in humans (p < 0.0001). No significant difference was observed in thrombin time (p = 0.1949). CONCLUSIONS: In summary, TEG could be used to evaluate thrombosis and bleeding parameters in whole blood samples from hamsters. The platelet function of hamsters closely resembled that of humans, whereas their coagulation function was significantly stronger.

Time to maximum amplitude of thromboelastography can predict mortality in patients with severe COVID-19: a retrospective observational study.

Objective: To predict mortality in severe patients with COVID-19 at admission to the intensive care unit (ICU) using thromboelastography (TEG). Methods: This retrospective, two-center, observational study involved 87 patients with PCR-and chest CT-confirmed severe COVID-19 who were admitted to at Wuhan Huoshenshan Hospital and the 908th Hospital of Chinese PLA Logistic Support Force between February 2020 and February 2023. Clinic demographics, laboratory results, and outcomes were compared between those who survived and those who died during hospitalization. Results: Thromboelastography showed that of the 87 patients, 14 were in a hypercoagulable state, 25 were in a hypocoagulable state, and 48 were normal, based on the time to maximum amplitude (TMA). Patients who died showed significantly lower α angle, but significantly longer R-time, K-time and TMA than patients who survived. Random forest selection showed that K-time, TMA, prothrombin time (PT), international normalized ratio (INR), D-dimer, C-reactive protein (CRP), aspartate aminotransferase (AST), and total bilirubin (Tbil) were significant predictors. Multivariate logistic regression identified that TMA and CRP were independently associated with mortality. TMA had a greater predictive power than CRP levels based on time-dependent AUCs. Patients with TMA ≥ 26.4 min were at significantly higher risk of mortality (hazard ratio 3.99, 95% Confidence Interval, 1.92-8.27, p < 0.01). Conclusion: TMA ≥26.4 min at admission to ICU may be an independent predictor of in-hospital mortality for patients with severe COVID-19.

Individualized antiplatelet therapy for non-cardiogenic ischemic stroke.

OBJECTIVE: This research aims to investigate the impact of individualized antiplatelet therapy guided by thromboelastography with platelet mapping (TEG-PM) on the clinical outcomes of patients with non-cardiogenic ischemic stroke. METHODS: Among a total of 1264 patients, 684 individuals diagnosed with non-cardiogenic ischemic stroke underwent TEG-PM testing. Based on the adjustment of antiplatelet medication, these patients were divided into individual and control groups. Within the individual group, in accordance with the TEG-PM test results, a Maximum amplitude (MA) value greater than 47mm was defined as high residual platelet reactivity (HRPR), while an MA value less than 31mm was defined as low residual platelet reactivity (LRPR). Patients with arachidonic acid (AA) less than 50% and adenosine diphosphate (ADP) less than 30% were classified as aspirin-resistant or clopidogrel-resistant. Treatment strategies for antiplatelet medication were subsequently adjusted accordingly, encompassing increment, decrement, or replacement of drugs. Meanwhile, the control group maintained their original medication regimen without alterations. RESULTS: The individual group included 487 patients, while the control group had 197. In the individual group, approximately 175 patients (35.9%) were treated with increased medication dosages, 89 patients (18.3%) with reduced dosages, and 223 patients (45.8%) switched medications. The results showed that the incidence rate of ischemic events in the individual group was lower than that of the control group (5.54% vs. 12.6%, P = 0.001), but no significant difference was observed in bleeding events. Cox regression analysis revealed age (hazard ratio, 1.043; 95% CI, 1.01-1.078; P = 0.011) and coronary heart disease (hazard ratio, 1.902; 95% CI, 1.147-3.153; P = 0.013) as significant risk factors for adverse events. CONCLUSION: Individualized antiplatelet therapy based on TEG-PM results can reduce the risk of ischemic events in patients with non-cardiogenic ischemic stroke without increasing the risk of bleeding events or mortality. Advanced age and coronary heart disease were identified as risk factors affecting the outcomes of individualized antiplatelet therapy.

Variability of fibrinolytic activity in pregnant patients exposed to tissue plasminogen activator: an in vitro study utilizing rotational thromboelastometry.

BACKGROUND: The investigation into the variability of fibrinolysis in obstetric patients is notably limited despite its relevance to postpartum hemorrhage. We investigate an in vitro model of fibrinolysis measured by rotational thromboelastrometry (ROTEM) in maternal blood samples with lysis stimulated by tissue plasminogen activator (tPA). METHODS: Written informed consent was obtained from 19 patients at term pregnancy during admission to the labor and delivery unit. Patients who were taking medication affecting coagulation were excluded. Tissue plasminogen activator was added to whole blood samples to a final concentration of 100 or 220 ng/mL prior to ROTEM testing. RESULTS: The addition of tPA produced high intra-individual fibrinolytic variability for clot firmness and lysis parameters. Patients responded differently to each tPA dose ranging from clot lysis within the range of 0 ng/mL tPA group to complete clot lysis. The coefficient of variation (CV) values for the 220 ng/mL tPA group were: EXTEM MCF 0.510, EXTEM LI30 1.601, FIBTEM MCF 0.349, FIBTEM LI30 2.097. CV values for the 100 ng/mL tPA group were: EXTEM MCF 0.144, EXTEM LI30 1.038, FIBTEM MCF 0.096, FIBTEM LI30 1.238. CONCLUSION: We demonstrate a wide range of fibrinolytic response in the obstetric population to exogeneous tPA. We found subgroups of patients that were very responsive to tPA and insensitive to tPA. This study represents a preliminary exploration into classifying the obstetric fibrinolytic phenotypes. Further research will integrate relevant coagulation factors to establish a predictive model for testing susceptibility to lysis that can be applied at the point of care.