Pulmonary Embolism Doug Bretzing, pgy 3 https://www.slideshare.net/steveclaydon1970/pulmonary-embolism-pe-51686443

Definition Obstruction of the pulmonary artery or one of its branches by material Thrombus Tumor Air Fat

Nomenclature Massive – Sustained hypotension, systolic blood pressure < 90 mmHg for at least 15 minutes OR requiring inotropic support, or PE resulting in pulselessness Submassive – Acute PE without hemodynamic instability but resulting in right ventricular dysfunction or myocardial necrosis Clinically “Low Risk” - PE that doesn’t meet the above definitions

Epidemiology Incidence 112 cases in 100,000 in one database Higher in males Rises with increasing age Accounts for approximately 100,000 annual deaths in the US (probably even higher due to sudden cardiac death) Mortality 30 day – 4% 1 year – 13%

Risk factors for vte Virchow’s Triad Alterations in blood flow Vascular endothelial injury Alterations in the constituents of blood

source Most arise from lower extremity proximal veins (iliac, femoral, and popliteal) More than 50% of patients with proximal DVT have concurrent PE Calf vein DVT rarely embolizes to the lung and two–thirds of calf vein thrombi resolve spontaneously after detection

pathophysiology Infarction – Occurs in about 10% of patients Small thrombi lodge distally in to the segmental and subsegmental vessels More likely to have pleuritic chest pain and hemoptysis Name that sign! https://www.vcuthoracicimaging.com/Imagewindow.aspx?imgname=Uploadimg\Picture10941279870398.jpg&caption=

Pathophysiology Abnormal gas exchange due to mechanical and functional obstruction of the vascular bed altering the ventilation to perfusion ratio (V/Q Mismatch) Cardiovascular compromise Hypotension due to diminished stroke volume and cardiac output Increased pulmonary vascular resistance due to physical obstruction and hypoxic vasoconstriction RV dilation Decreased LV preload Decreased CO https://www.slideshare.net/doctoranish/pulmonary-embolism-radiology

Workup ABG Hypoxemia (74%) Respiratory alkalosis and hypocapnia (41%) BNP Limited diagnostic utility Useful prognostically for risk stratification (and nomenclature) Troponin Similar utility as BNP

workup EKG Most common findings? (70%) S1Q3T3, RV strain, new incomplete RBBB uncommon (< 10%) http://journalofclinicaltrialresults.com/wp-content/uploads/2015/06/Figure-3-Ho_Smouse.jpg

workup Echocardiogram Useful for prognostic purposes in patients with CONFIRMED PE New RV strain and RV thrombus are poor prognostic indicators https://youtu.be/f_QgPo4c6XU

treatment

Long-term anticoagulation

Pleural effusion

Indications for thoracentesis Newly detected pleural effusion (unless there is an obvious cause, such as CHF) Symptom relief Imaging characteristics of complicated pleural effusion (e.g. loculations) At least 1 cm pleural fluid on CXR or US

Light’s criteria Pleural fluid protein/serum protein ratio greater than 0.5, or Pleural fluid LDH/serum LDH ratio greater than 0.6, or Pleural fluid LDH greater than two-thirds the upper limits of the laboratory's normal serum LDH

references https://www.uptodate.com/contents/overview-of-acute-pulmonary-embolism-in- adults?search=pulmonary%20embolism&source=search_result&selectedTitle=1~150&usage_t ype=default&display_rank=1 https://www.uptodate.com/contents/diagnostic-evaluation-of-a-pleural-effusion-in-adults- initial- testing?search=pleural%20effusion&source=search_result&selectedTitle=1~150&usage_type= default&display_rank=1#H2 https://en.wikipedia.org/wiki/James_Stewart#Death https://www.mdcalc.com/geneva-score-revised-pulmonary-embolism https://imgflip.com/memegenerator/Oprah-You-Get-A http://www.acc.org/latest-in-cardiology/ten-points-to- remember/2016/03/02/15/45/antithrombotic-therapy-for-vte-disease https://slideplayer.com/slide/4721194/