Pulmonary embolism
Formal Definition
A blockage of the pulmonary artery by a thrombus, fat, air, or tumor cells; most commonly from deep vein thrombosis; presents across a spectrum from incidental finding to massive PE causing hemodynamic collapse; diagnosis via CT pulmonary angiography, V/Q scan, or bedside echocardiography; stratified by risk (massive/submassive/low-risk) to guide management.
How It's Used on the Ward
PE or pulmonary embolus or got a clot to the lung — a blood clot that traveled to the lungs; range from a small incidental finding to a fatal event.
Example
"42-year-old on OCP, now 8 days post-knee surgery, acute onset dyspnea and pleuritic chest pain. CTPA shows filling defect in right main pulmonary artery. Troponin I elevated at 0.8, echo shows RV strain. Risk stratification: submassive PE. Started heparin drip, telemetry, hemodynamic monitoring. Consultation for catheter-directed thrombolysis considered given RV dysfunction."
Clinical Context
Wells score for PE probability. D-dimer: negative rules out in low-probability; positive in high-probability requires imaging. CTPA: gold standard; contraindicated in contrast allergy or severe renal failure → V/Q scan. Massive PE (hemodynamic collapse): hypotension, PEA, syncope → thrombolysis (tPA) if no contraindications. Submassive: normal BP but RV strain (echo, elevated BNP/troponin) → anticoagulation, consider catheter or systemic thrombolysis based on institutional protocol. Thrombolysis contraindications: prior hemorrhage, structural GI lesion, known AV malformation, malignant neoplasm. IVC filter: for patients with absolute contraindication to anticoagulation.