RT Book, Section A1 Meyer, Nuala J. A1 Schmidt, Gregory A. A2 Hall, Jesse B. A2 Schmidt, Gregory A. A2 Wood, Lawrence D.H. SR Print(0) ID 2285540 T1 Chapter 27. Pulmonary Embolic Disorders: Thrombus, Air, and Fat T2 Principles of Critical Care, 3e YR 2005 FD 2005 PB The McGraw-Hill Companies PP New York, NY SN 9780071416405 LK accessmedicine.mhmedical.com/content.aspx?aid=2285540 RD 2022/08/14 AB Pulmonary embolism (PE) is common, underdiagnosed, and lethal, yet readily treatable.Prophylaxis and accurate diagnosis are essential to improving outcome.The cause of death in PE is most often circulatory failure (acute cor pulmonale) due to right heart ischemia.There is no perfect diagnostic test for PE; accurate diagnosis requires both an informed clinical pretest probability and a stepwise application of tests including D-dimer, helical CT angiography, and lower extremity duplex.A careful risk assessment may identify patients ideal for outpatient therapy. Conversely, patients with hypotension, cancer, heart failure, hypoxemia, and present or prior deep vein thrombosis are at significantly higher risk for death, recurrence, or major bleeding from PE, and are best managed in an appropriately monitored setting.Low molecular weight heparin (LMWH) is approved and recommended as the initial therapy for PE, and should be used in most patients unless there exists a compelling reason to do otherwise. When LMWH is not used, unfractionated heparin is typically used to maintain the partial thromboplastin time at 1.5 to 2.5 times control. Numerous new anticoagulants are being tested and may soon be approved for the treatment of PE.Critically ill patients may especially benefit from aggressive use of vena caval interruption.Thrombolytic therapy is life-saving in patients with massive embolism and circulatory instability.Air and fat embolism usually present as acute respiratory distress syndrome, and are managed with mechanical ventilation, oxygen, and positive end-expiratory pressure.