Pulmonary Embolism

Pulmonary embolism (PE) is an obstruction of one or more pulmonary arteries, most commonly by a blood clot (thrombus) that originates in the deep veins of the legs or pelvis (deep vein thrombosis — DVT). PE is the third most common acute cardiovascular syndrome after myocardial infarction and stroke, and it carries a mortality rate of roughly 10 to 30 percent when it is not recognized and treated promptly. Because most emboli arise from a DVT, the two conditions are grouped together under the umbrella term venous thromboembolism (VTE), and prevention of VTE is inseparable from its treatment. PE exists on a clinical spectrum that drives both urgency and treatment choice: - Low-risk PE: hemodynamically stable, no right ventricular (RV) strain, normal cardiac biomarkers. - Intermediate-risk PE: RV strain seen on echocardiogram or elevated troponin/BNP, but the person remains hemodynamically stable. - High-risk PE: hemodynamic instability — systolic blood pressure below 90 mmHg or the need for vasopressors — with mortality that may exceed 50 percent. For the NCLEX-RN, the high-yield pattern is the sudden onset of dyspnea, pleuritic chest...