Resp 180 Exam 3: Pulmonary Embolism and Infarction

  1. What is Pulmonary Embolism?
    When a blood clot breaks loose from somewhere else & floats into the pulmonary circulation
  2. When does Pulmonary Infarction develop? What does an Infartion lead to?
    • When embolus interrupts pulmonary blood flow. 
    • Atelectasis, consolidation, and tissue necrosis
  3. Changes in lungs from Pulmonary Embolism & Infarction
    • Bronchoconstriction: release of mediators-serotonin, histamine & prostaglandins. Also hypocapnia & hypoxemia
    • 1 big clot (fatal) or bunch of smaller ones
  4. Summary of Pulmonary Embolism & Infarction changes in the lungs
    • Blockage of pulmonary vessel
    • Pulmonary infarction
    • Atelectasis
    • Consolidation
    • Maybe bronchoconstriction
  5. How many cases of PE are missed? Common symptoms?
    • 70%
    • 90% in pts younger than 70 years
    • Dyspnea, hemoptysis & pleuritic chest pain are seen in over 20% of pts
  6. When to suspect Pulmonary Embolism?
    Dyspnea, tachypnea & chest pain
  7. What's the most common cause of Pulmonary Embolism?
    Blood clot
  8. Where do clots come from?
    • Deep veins in legs, pelvis or inferior vena cava.
    • When a piece breaks off, clot moves through veins RA and RV of heart and impacts in the PA or artioles
  9. Risk factors of Pulmonary Embolism?
    • Venous statis: lengthy bed rest
    • Trauma: bone fx.
    • Post-op/postpartum: hip surgeries or "milk leg"
    • Misc: obesity, cancer & burns
  10. Clinical signs/symptoms of Pulmonary Embolism
    • High resp rate
    • High heart rate
    • Systemic hypotension
    • Cyanosis
    • Cough/hemoptysis
    • JVD
    • Swollen, tender liver
    • Chest pain/decrease chest expansion
    • Syncope/dizziness/confusion
    • AbNL heart sounds
    • Crackles/wheezes/pleural friction rub
  11. ABGs of Pulmonary Embolism
    • Mild to moderate PE: acute alveolar hypervent'n with hypoxemia
    • Severe PE/Infarction: acute vent'y failure with hypoxemia
  12. Oxygenation of PE?
    • Increase: shunting/total flow & O2 extraction ratio
    • Decrease: O2 delievery & mixed venous O2 consumption
    • NL: venous O2 & arterial to mixed venous oxygen content difference
  13. Hemodynamics of Pulmonary Embolism?
    • Increase: Central Venous Pressure, Right Arterial Pressure, Pulmonary Artery Pressure & Pulmonary Vascular Resistance
    • Decrease: PCWP, Stroke Volume, Stroke Volume Index, CO & Cardiac Index
    • NL: System Vascular Resistance
  14. What to use to diagnosis Pulmonary Embolism?
    • ECG
    • CXR
    • V/Q
    • Pulmonary angiography
    • CT scan
    • Fibrinogen test
    • Extremity venography
    • Duplex ultrasonography
    • MRI
  15. Diagnosis of Pulmonary Embolism: ECG:
    • Sinus/atrial tach
    • arrhythmias
    • AFlutter
    • AFib
    • Right Bundle Branch Block
    • P-pulmonale
  16. Diagnosis of Pulmonary Embolism: CXR:
    • Increase density (whiter) 
    • Hyperradiolucency distal to embolus in non-infarcted areas
    • big PA
    • Pulmonary Edema
    • Cor pulmonale
    • Small pleural effusion
  17. Diagnosis of Pulmonary Embolism: V/Q
    • Shows noramal ventilation
    • Normal perfusion
  18. Diagnosis of Pulmonary Embolism: Pulmonary angiography:
    • abNL filling or cutoff
    • areas with no perfusion will be dark
    • If V/Q scan is NL, this angiogram will be negative
  19. Diagnosis of Pulmonary Embolism: CT Scan:
    • Good to dx PE
    • Fast
    • Less invasive
    • Don't need pulmonary cath
  20. Diagnosis of Pulmonary Embolism: Fibrinogen test:
    • Checks for high levels of fibrinogen (blood clotting protein)
    • Normal result rules out PE
  21. Diagnosis of Pulmonary Embolism: Extremity Venography:
    • Put cath in arm or leg vein, inject dye
    • not used much today
  22. Diagnosis of Pulmonary Embolism: Duplex ultrasonography:
    • Noninvasive
    • Uses high-frequency sound waves to I.D. clots in thigh veins
    • Good to dx DVT above knee, bad for DVT below knee
  23. Diagnosis of Pulmonary Embolism: MRI:
    • Good to use if kidneys may be harmed by dyes
    • useful in pregnancy
  24. Management of Pulmonary Embolism?
    • Pulse ox
    • ECG monitoring
    • Anticoagulants: blood thinner. Fast: Heparin Slow: Warfarin DON'T use with IBUPROFEN
    • Thrombolytics: urokinase, streptokinase, alteplase
    • Vein filter
    • O2 therapy: decrease WOB & myocardial work, treat hypoxemia
    • Elastic stockings
    • Meds: for bronchoconstriction
    • Mechanical ventilation
    • Pulmonary embolectomy: last resort-high mortality
Card Set
Resp 180 Exam 3: Pulmonary Embolism and Infarction
When a blood clot breaks loose from somewhere else and floats into the pulmonary circulation.