Seminars in respiratory and critical care medicine
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Semin Respir Crit Care Med · Feb 2017
ReviewApproach to Suspected Acute Pulmonary Embolism: Should We Use Scoring Systems?
Modern diagnostic strategies for pulmonary embolism diagnosis almost all rely on an initial assessment of the pretest probability. Clinical prediction rules are decision-making tools using combinations of easily available clinical predictors to define the probability of a disease. ⋯ They should be derived and validated following strict methodological standards. The use of clinical prediction rules should be encouraged, since their implementation in local guidelines for pulmonary embolism diagnosis has been shown to improve patients' outcomes.
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Semin Respir Crit Care Med · Feb 2017
ReviewMassive Pulmonary Embolism: Extracorporeal Membrane Oxygenation and Surgical Pulmonary Embolectomy.
Massive pulmonary embolism (PE) refers to large emboli that cause hemodynamic instability, right ventricular failure, and circulatory collapse. According to the 2016 ACCP Antithrombotic Guidelines, therapy for massive PE should include systemic thrombolytic therapy in conjunction with anticoagulation and supportive care. However, in patients with a contraindication to systemic thrombolytics or in those who fail the above interventions, extracorporeal membrane oxygenation (ECMO) and/or surgical embolectomy may be used to improve oxygenation, achieve hemodynamic stability, and successfully treat massive PE. ⋯ Unfortunately, ECMO requires full anticoagulation to maintain the functionality of the system; hence, significant bleeding complicates its use in 35% of patients. Contraindications to ECMO include high bleeding risk, recent surgery or hemorrhagic stroke, poor baseline functional status, advanced age, neurologic dysfunction, morbid obesity, unrecoverable condition, renal failure, and prolonged cardiopulmonary resuscitation without adequate perfusion of end organs. In this review, we discuss management of massive PE, with an emphasis on the potential role for ECMO and/or surgical embolectomy.
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Semin Respir Crit Care Med · Feb 2017
ReviewReversal of Direct Oral Anticoagulants: Current Status and Future Directions.
Direct oral anticoagulants (DOACs) are increasingly used for prevention and treatment of venous thromboembolism and for prevention of stroke in patients with nonvalvular atrial fibrillation. In phase III clinical trials that included more than 100,000 patients, the DOACs were at least as effective as vitamin K antagonists (VKAs) and were associated with less serious bleeding, particularly less intracranial bleeding. Real-world evidence supports these outcomes. ⋯ Anticoagulant reversal should only be considered with life-threatening bleeds, with bleeds that fail to respond to usual measures and in patients requiring urgent surgery. Idarucizumab is licensed for dabigatran reversal and andexanet alfa is likely to be soon licensed for reversal of rivaroxaban, apixaban, and edoxaban. To ensure responsible use of these agents, every hospital needs a bleeding management algorithm that identifies patients eligible for reversal and outlines appropriate dosing regimens.
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Semin Respir Crit Care Med · Feb 2017
ReviewSystemic Thrombolytic Therapy for Acute Pulmonary Embolism: Who Is a Candidate?
Pulmonary embolism (PE) is a major cause of both acute and long-term morbidity for a large number of patients worldwide, and massive PE is frequently fatal. Right ventricular (RV) dysfunction is a key determinant of prognosis in the acute phase of PE. Patients with clinically overt RV failure, that is, with cardiogenic shock or persistent hypotension at presentation (acute high-risk PE), are clearly in need of immediate reperfusion treatment with systemic thrombolysis or, alternatively, surgical or catheter-directed techniques. ⋯ Thus, current guidelines agree in proposing a strategy of effective anticoagulation and "watchful waiting" (with initial hemodynamic monitoring notably over the first 48-72 hours) in intermediate-risk PE, with an indication for rescue thrombolysis if signs of hemodynamic decompensation appear. Recently published trials suggest that catheter-directed, ultrasound-assisted, low-dose local fibrinolysis may provide an effective and particularly safe treatment option for some of these patients. Ongoing or planned studies are expected to resolve the controversy on the efficacy and safety or reduced-dose systemic thrombolysis and to address the possible impact of thrombolytic therapy on long-term outcomes after acute PE.
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Semin Respir Crit Care Med · Feb 2017
ReviewRisk Stratification for Proven Acute Pulmonary Embolism: What Information Is Needed?
Classification of risk drives treatment decisions for patients with acute symptomatic pulmonary embolism (PE). High-risk patients with acute symptomatic PE have hemodynamic instability (i.e., shock or hypotension present), and treatment guidelines suggest systemically administered thrombolytic therapy in this setting. Normotensive PE patients at low risk for early complications (low-risk PE) might benefit from treatment at home or early discharge, while normotensive patients with preserved systemic arterial pressure deemed as having a high risk for PE-related adverse clinical events (intermediate-high-risk PE) might benefit from close observation and consideration of escalation of therapy. Prognostic tools (e.g., clinical prognostic scoring systems, imaging testing, and cardiac laboratory biomarkers) assist with the classification of patients into these categories.