Evaluation Of Coagulation Status Research Articles

Prognostic Role of Initial Thromboelastography in Emergency Department Patients with Primary Postpartum Hemorrhage: Association with Massive Transfusion.

The early prediction of the need for massive transfusions (MTs) and the preparation of blood products are essential for managing patients with primary postpartum hemorrhage (PPH). Thromboelastography (TEG) enables a thorough evaluation of coagulation status and is useful for guiding the treatment of hemorrhagic events in various diseases. We investigated the role of TEG in predicting the need for MT in patients with primary PPH. A retrospective observational study was conducted in the emergency department (ED) of a university-affiliated, tertiary referral center between November 2015 and August 2023. TEG was performed upon admission. We defined MT as the requirement for transfusion of more than 10 units of packed red blood cells within the first 24 h. The primary outcome was the need for MT. Among the 184 patients with initial TEG, 34 (18.5%) required MT. Except for lysis after 30 min, the MT and non-MT groups had significantly different TEG values. Based on multivariate analysis, an angle < 60 was an independent predictor of MT (odds ratio (OR) 7.769; 95% confidence interval (CI), 2.736-22.062), along with lactate (OR, 1.674; 95% CI, 1.218-2.300) and shock index > 0.9 (OR, 4.638; 95% CI, 1.784-12.056). Alpha angle < 60 degrees indicated the need for MT with 73.5% sensitivity, 72.0% specificity, and 92.3% negative predictive value. Point-of-care testing of TEG has the potential to be a useful tool in accurately predicting the necessity for MT in ED patients with primary PPH at an early stage.

Evaluation of coagulation status using clot waveform analysis in general ward patients with COVID-19.

Coronavirus disease (COVID-19)-related systemic cytokine response induces the production of procoagulant factors, which predisposes patients to a prothrombotic state. Viscoelastic testing can identify the degree of hypercoagulability, which is related to outcomes. We aimed to study the changes in clot waveform analysis (CWA) parameters in COVID-19 patients on hospital admission compared to those in a group of healthy individuals. We conducted a retrospective study of COVID-19 patients admitted to general wards and evaluated demographic and clinical parameters as well as laboratory parameters, including coagulation parameters. CWA data from patients (n = 62) with COVID-19 prior to the initiation of anticoagulation therapy were compared with those from healthy controls (n = 67). The measured CWA parameters were min1, min2, max2, and delta change. CWA, fibrinogen, and D-dimer values were higher in COVID-19 patients than in healthy controls (p < 0.001). CWA profiles were consistent with hypercoagulability and characterized by an increase in density, velocity, and acceleration of clot formation. Activated partial thromboplastin time, fibrinogen, D-dimer, and C-reactive protein (CRP) values were higher in patients in whom all CWA parameters were raised than in patients with just a few elevated CWA parameters, while Sequential Organ Failure Assessment scores, prothrombin time, fibrin degradation product levels and platelet counts did not differ between the two groups. CWA variables showed hypercoagulopathy on admission in COVID-19 patients who were hospitalized in the general ward, and this pattern was more pronounced in critically ill patients with elevated fibrinogen, D-dimer, and CRP levels. Our results may help identify patients at high risk of thromboembolism.

Evaluation of coagulation status using viscoelastic testing in intensive care patients with coronavirus disease 2019 (COVID-19): An observational point prevalence cohort study

BackgroundCoronavirus Disease-19 (COVID-19) is associated with a high rate of thrombosis, the pathophysiology of which is not well defined. Viscoelastic testing may identify and characterise hypercoagulable states which are not apparent using conventional coagulation assays. ObjectivesThe objective of this study was to undertake viscoelastic evaluation of the coagulation state in critically ill adults with COVID-19–associated respiratory failure MethodsThis was a single-centre observational point prevalence cohort study of adults with COVID-19–associated respiratory failure requiring respiratory support in the intensive care unit. Coagulation status was evaluated using rotational thromboelastometry (ROTEM®) in conjunction with laboratory markers of coagulation. ResultsSix patients fulfilled inclusion criteria. Each patient had one ROTEM® performed. All patients had supranormal clot amplitude at 10 min (A10) and supranormal clot firmness (maximal clot firmness) measured in at least one ROTEM® pathway, and five were supranormal on all pathways. Minimal clot lysis was present on all analyses. Fibrinogen and D-dimer were elevated and routine markers of coagulation within normal ranges in all patients. ConclusionPatients with COVID-19–associated respiratory failure admitted to the intensive care unit exhibit a hypercoagulable state which is not appreciable on conventional tests of coagulation. Supranormal clot firmness, minimal fibrinolysis, and hyperfibrinogenaemia are key findings. Further research is required into the pathophysiology of this hypercoagulable state, as well as the harms and benefits of different anticoagulation strategies.

4:03 PM Abstract No. 362 To screen or not to screen: can we accurately limit the preoperative testing of coagulation status in patients undergoing placement of tunneled central venous catheter to only those that need it?

To determine if the preoperative screening and evaluation of coagulation status in patients undergoing placement of a tunneled central venous catheter, as reflected by the platelet count and the calculated International Normalized Ratio (INR), can be accurately limited to specific patients based upon known risk factors and relevant past medical history in accordance with the recommendations set forth in the updated SIR Guidelines for the Periprocedural Management of Bleeding Risk. We conducted a retrospective analysis of tunneled central venous catheter placements performed by interventional radiology in both the ambulatory and inpatient setting at a single institution over a 12-month period between August 1st, 2018 and July 31st, 2019. The preoperative platelet and INR values were compiled from the electronic medical record. Any encountered platelet or INR abnormalities (platelet count < 20 x 109/L, INR > 3.0) were then cross-referenced to the relevant patient medical history to determine the etiology of the coagulation deficit. A total of 578 tunneled central venous catheters (142 ports, 103 permacaths, 16 Hickman catheters, 317 Powerline catheters) were placed during the study period. Coagulation testing was performed within 3 days or 30 days of the procedure (inpatient vs. ambulatory setting, respectively) in accordance with current departmental protocol. Of the 578 tunneled catheter placements, 1 patient (0.17%) demonstrated an INR value above the threshold limit and 12 patients (2.1%) possessed a platelet count below the recommended transfusion threshold. The laboratory abnormalities in all cases were easily explained: the elevated INR was secondary to Coumadin therapy for atrial fibrillation and the thrombocytopenia was related to a hematologic malignancy in every instance. The presence of a coagulation deficit in a patient undergoing a tunneled central venous catheter placement is rare and, when encountered, explained by a review of the relevant past medical history. These findings support the updated Periprocedural Guidelines for low bleeding risk procedures recommending preoperative laboratory screening only in patients with relevant risk factors.

Comparison of two blood sampling techniques for the determination of coagulation parameters in the horse: Jugular venipuncture and indwelling intravenous catheter

Evaluation of coagulation status is an important component of critical care. Ongoing monitoring of coagulation status in hospitalised horses has previously been via serial venipuncture due to concerns that sampling directly from the intravenous catheter (IVC) may alter the accuracy of the results. Adverse effects such as patient anxiety and trauma to the sampled vessel could be avoided by the use of an indwelling IVC for repeat blood sampling. To compare coagulation parameters from blood obtained by jugular venipuncture with IVC sampling in critically ill horses. Prospective observational study. A single set of paired blood samples were obtained from horses (n = 55) admitted to an intensive care unit by direct jugular venipuncture and, following removal of a presample, via an indwelling IVC. The following coagulation parameters were measured on venipuncture and IVC samples: whole blood prothrombin time (PT), fresh plasma PT and activated partial thromboplastin time (aPTT) and stored plasma antithrombin activity (AT) and fibrinogen concentration. D-dimer concentration was also measured in some horses (n = 22). Comparison of venipuncture and IVC results was performed using Lin's concordance correlation coefficient. Agreement between paired results was assessed using Bland Altman analysis. Correlation was substantial and agreement was good between sample methods for all parameters except AT and D-dimers. Each coagulation parameter was tested using only one assay. Sampling was limited to a convenience sample and timing of sample collection was not standardised in relation to when the catheter was flushed with heparinised saline. With the exception of AT and D-dimers, coagulation parameters measured on blood samples obtained via an IVC have clinically equivalent values to those obtained by jugular venipuncture.

Application of thromboelastography in evaluation of coagulation status in late pregnant women

Objective To explore the application value of thromboelastography (TEG) in evaluation of coagulation status in late pregnancy women.Methods The results of TEG detection and coagulation function test were analyzed retrospectively in 84 late pregnancy women.The difference in detecting abnormal coagulation function was compared between the two methods.Results There were 10 late pregnancy women (11.9％) with abnormal coagulation function detected by TEG detection,and 26 (31.0％) with abnormal coagulation function detected by routine coagulation function test.The difference in detection rate of abnormal coagulation function was statistically significant between the two methods(x2 =4.53,P ＜ 0.05).Conclusion Hypercoagulable status in late pregnancy women detected by TEG detection was better than detected by routine coagulation function test. Key words: Late pregnant; Thromboelastography; Coagulation status

Evaluation of coagulation status in dogs with naturally occurring canine hyperadrenocorticism

To determine whether or not there are differences in coagulation parameters (eg, thrombelastography [TEG], activated partial thromboplastin time [aPTT], prothrombin time [PT], and fibrinogen) among dogs with naturally occurring hyperadrenocorticism (HAC), dogs with HAC undergoing medical management, and dogs without HAC. Prospective, observational study. Veterinary teaching hospital. Forty-six client-owned dogs undergoing adrenal function testing. None. Nine dogs were diagnosed with HAC de novo, 19 dogs were presented for therapeutic monitoring of previously diagnosed HAC, and 18 dogs did not have HAC. Variables compared between groups were age, body weight, platelet count, mean platelet volume, serum concentrations of cholesterol, triglycerides, antithrombin, PT, aPTT, fibrinogen, and TEG parameters (eg, alpha angle, R, K, and maximum amplitude [MA]). Dogs with HAC and dogs treated for HAC had higher serum cholesterol than dogs without HAC (P < 0.05). All groups had mean MA greater than the institutional reference interval. There was a weak, positive correlation between hematocrit and MA that was independent of diagnosis (r(2) = 0.266, P = 0.004). The results of this study do not support the supposition that a significant difference exists in coagulation tendencies between dogs with HAC prior to treatment, dogs with HAC during treatment, and dogs without HAC. This disagreement with the classically accepted notion that HAC leads to a hypercoagulable state could be due to a couple of possibilities. Namely, the link between HAC and hypercoagulability may be relatively weak, or our findings may be the result of a type II error either as a result of a small sample size or the use of coagulation assays that are insensitive to the effects of HAC on the hemostatic system.

Arzneimittelinteraktionen von Phenylbutazon und Phenprocoumon bei einem Warmblutpferd

A 15 year old Oldenburger gelding was treated during 3 weeks for laminitis with the anticoagulant phenprocoumone (27 mg orally, once daily) and concurrent administration of phenylbutazone (2-4 g orally, twice daily). After this treatment the animal was presented to the Equine Clinic University of Zurich with a history of acute colic and advanced symptoms of shock. On the basis of the clinical signs and laboratory values, a diagnosis of combined drug induced coagulopathy was made. The horse was treated with the antidote Vitamine-K1 (0.5 mg/kg, subcutaneously). Eventually, the general condition of the animal worsened and it was therefore euthanized. Necropsy revealed profound, multifocal hemorrhagic diathesis of the serosal surface of the viscera, as well as bleeding into the visceral cavities. This case shows that concurrent administration of phenprocoumone and phenylbutazone may lead to drug interactions that increase the anticoagulation effect of the coumarine-derivative. Simultaneous use of coumarine-derivatives and phenylbutazone is therefore contraindicated due to the higher risk of bleeding. A reasonable treatment of horses with anticoagulants requires regular monitoring with constant evaluation of coagulation status and special attention to potential drug interactions.

Development of Antitissue Factor Antibodies in Patients After Liver Surgery

AbstractAfter liver surgery, two patients developed unexplainable prolonged prothrombin times (PT) that were not associated with bleeding tendency. The substitution of rabbit thromboplastin for either human or monkey thromboplastin in performing PT tests resulted in a normal clotting time. Tissue factor (TF) procoagulant activity assays and an immunoblotting analysis showed that these patients had developed IgG X-type immediate anticoagulants directed against both rabbit and bovine TF that did not cross-react with either human or monkey TF. In a chromogenic assay, the patient IgG caused a decrease in both the Km and the Vmax of the factor X activation by rabbit TF-factor Vila complex. The lack of reactivity of the patient IgG with human TF presumably explained why there was no clinical bleeding. Both patients had been treated earlier with a topical hemostatic agent prepared from bovine corium, microfibrillar collagen hemostat, while undergoing previous surgery. In an immunoblotting analysis, the patient IgG stained a 42-Kd band in the Triton extract of the collagen preparation under either reducing or nonreducing conditions. The Triton extract of the collagen preparation blocked the binding of the patient IgG to bovine TF. Thus, it is suggested that the iatrogenic immunization by intraoperative exposure of bovine TF retained in the collagen preparation may be responsible for the development of anti-TF antibodies in these patients. The anti-TF antibodies resulted in a clinical error in the evaluation of coagulation status after the use of rabbit thromboplastin.

Coagulation studies in the preeclamptic parturient: A survey

Study Objective: To delineate current practice with regard to how coagulation status is evaluated before induction of regional anesthesia in the Preeclamptic parturient, with the goal of defining appropriate testing. Design: A confidential survey was mailed to the chairmen of all 113 anesthesiology residency training programs in the United States listed in the American Medical Association's American Medical Graduation Education guide, to be passed on to the director of obstetric anesthesia. Setting: Academic institutions providing obstetric anesthesia services in the United States. Interventions: Following the original study, there was no additional follow-up or intervention. Measurements and Main Results: The 21-question survey explored institutional characteristics such as the number of deliveries, the use of regional anesthesia, and the laboratory tests required prior to placement of a regional anesthetic in the mildly or severely Preeclamptic parturient under two degrees of operative urgency. In the 74 programs entered into the analysis, we found that regional anesthesia was used in the majority of cesarean sections and more than half of the vaginal deliveries. In an urgent situation, most of the programs required no test of coagulation status in the mild preeclamptic parturient and only a platelet count in the severe preeclamptic parturient. Conclusions: In the majority of academic programs in the United States, we found that the evaluation of coagulation status in the Preeclamptic parturient was based primarily on a platelet count. A review of the literature support this Pattern of testing.