Seminars in thrombosis and hemostasis
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Semin. Thromb. Hemost. · Jan 1997
Acquired antithrombin deficiency following severe traumatic injury: rationale for study of antithrombin supplementation.
Hemorrhage, head injury, and multiple organ dysfunction are the most frequent causes of mortality in patients who experience severe injury. Acceleration of the coagulation cascade is known to result in hemorrhage secondary to disseminated intravascular coagulation (DIC) and end-organ dysfunction, as manifest by pulmonary and renal failure. Few studies have been conducted to evaluate the effects of injury on the endogenous anticoagulants that inhibit excessive coagulation activation. ⋯ However, patients with adverse outcomes [DIC and adult respiratory distress syndrome (ARDS)] had significant reductions in AT and protein C activities. Decreased levels of AT and protein C 8 hours after admission served as independent predictors of both DIC and ARDS. Prospective, randomized studies should be conducted to evaluate the effect of supplementation of these factors after severe injury has occurred.
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Semin. Thromb. Hemost. · Jan 1999
Use of argatroban during percutaneous coronary interventions in patients with heparin-induced thrombocytopenia.
Percutaneous coronary revascularization (PTCR) procedures require intense anticoagulation during the procedure to reduce the risk of a thrombotic complication. This anticoagulation is almost always performed with unfractionated heparin. Heparin, however, is far from the ideal anticoagulant for use in PTCR, and its use is contraindicated in patients with known or suspected heparin-induced thrombocytopenia (HIT) or the heparin-induced thrombocytopenia and thrombosis syndrome (HITTS). ⋯ Argatroban was used in a trial of 50 patients with known or suspected HIT or HITTS who required PTCR. Adequate anticoagulation was achieved in 98% and there was procedural success in 98% with only 1 major bleeding event. These preliminary data suggest that argatroban can be used safely and effectively as an anticoagulant during PTCR in patients with known or suspected HIT or HITTS.
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Semin. Thromb. Hemost. · Apr 2013
Interference in coagulation testing: focus on spurious hemolysis, icterus, and lipemia.
The chance that errors might jeopardize the quality of testing is inherently present throughout the total testing process, especially in the preanalytical phase. In the coagulation laboratory, as well as in other areas of diagnostic testing, spurious hemolysis, icteria, and lipemia in test samples represent by far the leading diagnostic challenges. Interference in hemostasis testing due to spurious hemolysis is attributed to both analytical and biologic elements, namely high absorbance of cell-free hemoglobin at wavelengths used by optical instrumentation and release of both cytoplasmatic and plasma membrane molecules (e.g., tissue factor, proteases, phospholipids, and ADP) that can spuriously activate blood coagulation and platelets. ⋯ In practical terms, spurious hemolysis reflects a more generalized process of endothelial and blood cell damage, so that test results on spuriously hemolyzed specimens should be systematically suppressed. The bias attributable to hyperbilirubinemia is less significant using modern coagulometers equipped with dedicated wavelengths (i.e., with readings at 650 nm or above), so that test results in samples with a bilirubin concentration up to 20 mg/dL can still be analytically reliable. The interference observed in lipemic samples is most evident with readings using wavelengths lower than 500 nm and can hence be prevented with readings at 650 nm or above, and/or using higher dilutions of the test sample, or can be abated in high hypertriglyceridemic specimens (i.e., > 1,000 mg/dL) using high speed microcentrifugation or lipid extraction with organic solvents such as fluorine-chlorinated hydrocarbon, or lipid-clearing agents such as LipoClear (StatSpin Inc., Norwood, MA) and n-hexane.
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Semin. Thromb. Hemost. · Mar 2013
The approach to patients with bleeding disorders who do not accept blood-derived products.
Despite the widespread use of allogeneic blood components in clinical practice, there are patients in whom transfusion cannot be carried out for various reasons, including refusal of transfusions because of religious beliefs. The refusal of transfusion is not equivalent to refusal of medical treatment, and numerous options are available to effectively manage care without transfusions. ⋯ The strategies involve obtaining advance directive and consent to determine what components and procedures are acceptable to the patient; preoptimizing the patient for early correction of treatable deficiencies (e.g., anemia, coagulopathy); minimizing blood loss (e.g., hemostatic agents, blood salvage); and improving physiologic responses to anemia. Using these approaches, it is possible to effectively manage patients, with outcomes comparable to patients who accept transfusions.