Coagulopathy in the Trauma Patient
Stephen M. Cohn, Matthew O. Dolich, Kenji Inaba in Acute Care Surgery and Trauma, 2016
TEG parameters reflect clot formation time, clot strength, and clot breakdown. Reaction time or R time reflects the latent time until fibrin formation begins. A decrease in R time reflects hypocoagulability from factor deficiency or decreased factor activity, while shortened R time reflects hypercoagulability [10]. a angle reflects the rate of fibrin formation. Measures of clot strength are maximum amplitude (MA) and G, which measures clot elasticity. MA reflects the strength of platelet and fibrin interaction in the clot (Figure 10.2). Any defect in platelet count or function or decreased fibrin formation is reflected as a decrease in MA. High MA reflects hypercoagulability and is shown to be a risk factor for pulmonary embolism [11]. Fibrinolysis is measured by the parameters LY30 and LY60. LY30 and LY60 measure the rate of amplitude reduction at 30 and 60 min, respectively, after MA. A higher LY30 and LY60 reflect decreased clot stability and accelerated fibrinolysis (Figure 10.3) [1].
Acquired Circulating Anticoagulants And Defective Hemostasis In Malignant Paraprotein Disorders
Genesio Murano, Rodger L. Bick in Basic Concepts of Hemostasis and Thrombosis, 2019
Acquired inhibitors to blood coagulation factors have been described in several autoimmune disorders, most commonly systemic lupus erythematosus (SLE). A specific “lupus anticoagulant” has been identified and may precede the disease by several years. The presence of lupus anticoagulant is characterized by a prolonged partial thromboplastin time (PTT), a prolonged prothrombin time, prolongation of the PTT done on a mixture of normal plasma plus patients’ plasma, and a normal thrombin time and bleeding time.22 It remains unclear as to where this anticoagulant functions in the clotting sequence. Most of the evidence suggests that the activity is directed against prothrombin or a combination of the prothrombin complex factors. The inhibitor appears in approximately 6% of patients with SLE, and in many there is an associated deficiency of prothrombin. In those cases studied, the anticoagulant does not lead to a significant bleeding diathesis unless other associated coagulation defects are also present. Inhibitory activity correlates closely with disease activity and responds to immunosuppressive therapy. Other specific inhibitors to coagulation factors may also develop in SLE or any other of the collagen vascular diseases. The factors most commonly effected are Factors VIII, IX, XI, and XIII, as previously discussed.
Adnexal masses in the neonate, child, and adolescent
Joseph S. Sanfilippo, Eduardo Lara-Torre, Veronica Gomez-Lobo in Sanfilippo's Textbook of Pediatric and Adolescent GynecologySecond Edition, 2019
The adolescent ovarian cyst should be managed conservatively. Functional ovarian cysts may be either simple or complex on ultrasound imaging. Given their propensity for resolution in the absence of symptomatology requiring immediate surgical diagnosis (i.e., suspicion of torsion or malignancy), follow-up sonography at 6-week intervals will document resolution in the majority of adolescent ovarian cysts. The use of an oral contraceptive pill does not aid in regression of the functional ovarian cyst76 but is an option to prevent future cyst formation in an adolescent who experiences recurrent painful hemorrhagic cysts.85 Instructions should be given to both the adolescent and, if possible, her family during the observation period concerning symptoms of adnexal torsion that should lead them to seek assistance. A hemorrhagic cyst with a frank hemoperitoneum rarely may require surgical management. Patients on anticoagulants or with a bleeding diathesis are at greatest risk.86
Prospective assessment of platelet function in patients undergoing elective resection of glioblastoma multiforme
Published in Platelets, 2023
Santiago R. Leal-Noval, Manuel Casado, Cancela Palomares, José L. Narros, José L. García-Garmendia, Ginés Escolar, Diego X. Cuenca, Klaus Görlinger
Second, how and when coagulation is assessed by ROTEM is of paramount importance. In our study, we found a state of hypocoagulability (based on decreased ROTEM amplitude), rather than hypercoagulability (based on decreased PT/aPTT). The procoagulant activity of GBM has been documented by ROTEM in 21 patients with cerebral tumors (8 gliomas).28 All intra-operative data had median value within the ROTEM reference ranges, however a significant decreased CT-EXTEM and clot amplitude (MCF in EXTEM, INTEM and APTEM, except FIBTEM) and increased fibrinolisis (median ML > 50% in all the tests) were observed after spiking with tumor tissue extract own citrated whole blood. Authors concluded that there was a procoagulant state counterbalanced by strong hyperfibrinolysis and speculated that tumor extract induced and strong and early drop in platelets count and worsened platelet aggregation leading to reduced clot amplitude (MCF-EXTEM). We found reduced MCF in EXTEM, although we did not observe hyperfibrinolysis, nor did these authors find it in the basal ROTEM, without adding extracts of brain tissue.28
Acute coronary syndrome in patients with cancer
Published in Expert Review of Cardiovascular Therapy, 2022
Fisayomi Shobayo, Muhammad Bajwa, Efstratios Koutroumpakis, Saamir A. Hassan, Nicolas L. Palaskas, Cezar Iliescu, Jun-Ichi Abe, Elie Mouhayar, Kaveh Karimzad, Kara A. Thompson, Anita Deswal, Syed Wamique Yusuf
Thromboelastography (TEG) is a hemostatic tool used to determine the clotting efficacy of blood [117]; it has been proposed as a tool in the management of ACS in the thrombocytopenic patient. Agha and colleagues [118] report hypocoagulability in all patients with platelet counts below 20,000/mm3 and in 75% of patients with a platelet count below 50,000/mm3 [118]. Patients with a platelet count of <50,000/mm3 were more likely to have a hypocoagulable profile on TEG and had overall worse survival at 24 months [118]. Based on their data, the authors recommend TEG measurements in all patients with platelet count <50,000/ mm3 or in all patients with hematological malignancies before invasive coronary procedures [118]. Patients with platelet counts below 20,000/ mm3 have abnormal TEGs; TEG analysis in these patients may guide transfusion requirements if excessive bleeding does occur. A normal TEG in patients with platelet counts between 20,000–50,000/mm3 suggests a reduced risk of bleeding and portends a higher chance of survival [118]. Kasivisvanathan and colleagues [119] also show comparable results in their consecutive prospective analysis of bleeding risks in hematological malignancies and concurrent thrombocytopenia patients. All patients with bleeding episodes demonstrated hypocoagulability on TEG measurements compared to their non-bleeding counterparts [119].
Performance Evaluation of a New Point of Care Viscoelastic Coagulation Monitoring System in Major Abdominal, Orthopaedic and Vascular Surgery
Published in Platelets, 2020
Chris Brearton, Andrew Rushton, Jane Parker, Hannah Martin, Jake Hodgson
One limitation of the study was that none of the intra-operative samples for the Major Abdominal and Orthopedic Surgery groups had abnormal hemostasis. The study was intended to compare VCM and ROTEM® NATEM results for samples with coagulation statuses ranging from hypo- to hypercoagulable. This would have allowed a review of the agreement between the two systems across the likely measurement range and provided a good data set for regression analysis. The patient groups and sample times were selected with the aim of achieving this range of samples. However due to the limitation of selecting only elective patients it was difficult to predict when/if abnormalities of coagulation would occur. Pre-operative samples were expected to show normal coagulability, intra-operative samples from the Major Abdominal and Orthopedic Surgery were anticipated to show varying degrees of hypo- and hypercoagulability, whilst the Vascular Surgery patients were expected to show more extreme hypocoagulability. In reality, the vast majority of samples tested as part of this study fell within the ‘normal’ range on both systems, with the majority of the ‘abnormal’ samples coming from the Vascular Surgery group. This had two disadvantages. Firstly, that it limited our ability to review how the two systems correlate across the range of moderately hypocoagulable to hypercoagulable. Secondly, the available data was not ideal for regression analysis, as rather than a spread of data across a range the study gave two clusters of data points in the ‘normal’ and ‘extreme hypocoagulable’ ranges.
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