Complications of Pulmonary Embolism
Authors:
Sravya Kakumanu, Dean Percy, Yan Yu
Reviewers:
Tristan Jones, Ciara Hanly, Jieling Ma (马杰羚), Ben Campbell, Dr. Man-Chiu Poon*, Dr. Lynn Savoie*, Dr. Tara Lohmann * * MD at time of publication
IF CHRONIC:
Unresolved clot after 2 years leading to fibrosis of pulmonary vasculature
Chronic Thromboembolic Pulmonary Hypertension (CTEPH)
(<5% of PE cases) Venous Stasis Hypercoagulable state Vessel Injury Virchow’s Triad (*See Suspected Deep Vein Thrombosis slide) Deep Vein Thrombosis Clot migrates from deep limb veins à femoral àiliac veins ACUTE/MASSIVE PE: Clot obstructs pulmonary arterial or arteriolar flow Lung infarction (tissue death) from ischemia Inflammatory cells migrate to site and release cytokines ↑ Permeability of blood vessels Permeability-driven (exudate) fluid leakage into pleural space Pleural Effusion Clot migratesàinferior vena cava àright atrium (RA) of heartà right ventricle (RV) à gets lodged in pulmonary arteries/arterioles Pulmonary Embolism (PE) ↑ RV afterload ↑ RV pressure and expansion Well-ventilated (V) areas of lung do not receive adequate blood supply (Q) V/Q Mismatch Leftward shift of ventricular septum ↓ Left ventricle filling in diastole ↓ Cardiac output Obstructive Shock Impaired heart filling Pulseless Electrical Activity (ECG activity in absence of palpable pulse) Back up of pressure in systemic venous system ↑ Pressure in capillaries draining parietal pleura Pressure-driven (transudate) fluid leakage into pleural space For signs and symptoms, see the Obstructive Shock slide For signs and symptoms refer to CTEPH slide Chronic ↑ RV afterload ↑ Stretching of myocytes causing RV hypertrophy and dilation ↓ RV ejection fraction Right Heart Failure “Cor Pulmonale” For signs and symptoms, see the Right Heart Failure slide Failure to oxygenate blood Type I Respiratory Failure Hypoxemic: patient has ↓ blood [O2] IF MASSIVE PE (less common): ↑ Alveolar dead space Failure to ventilate Type II Respiratory Failure Hypercapnic: patient has ↑ blood [CO2] Legend: Pathophysiology Mechanism Sign/Symptom/Lab Finding Complications Published August 7, 2012, updated Mar 31, 2022 on www.thecalgaryguide.com