Pulmonary Circulation Disorders Flashcards
Refers to the movement of a clot (most commonly blood) from a systemic vein through the right side of the heart and into the pulmonary
Pulmonary Embolism
What is the most common preventable cause of hospital death?
Pulmonary Embolism
3rd most common vessel death after MI and stroke
Pulmonary Embolism
Most pulmonary embolisms arise from where?
thrombi in venous circulation of lower extremities 🡪 thromboembolism (typically around a valve)
What are other sources of pulmonary embolisms besides a LE thrombi?
Amniotic fluid
Air
Fat
Bone Marrow
Intravenous material
Septic emboli
What percentage of PE’s originate as clots in the deep veins of lower extremities, mostly in calves
70%
List some risk factors for a PE
Hypercoagulable States
Limb stasis (immobilization)
Prior DVT/PE
Malignancy
Age >45 years
Obesity
CHF
Trauma within the past 4 weeks
Surgery within the past 4 weeks
Major surgery
Serious infection
Virchow’s Triad
Local trauma to vessel wall (endothelial injury)
Hypercoagulability
Stasis or stagnation of the blood
Why can a diagnosis of PE be so difficult?
No single sign or symptom or combination of clinical findings are
indicative of a PE
there is not one single diagnostic test we can do to make the diagnosis
What is a rule that can help with a PE diagnosis?
The PERC Rule – Pulmonary Embolism Rule Out Criteria
(aids - not absolute)
When measuring and comparing the contralateral leg in suspicion for PE, what difference should you be concerned about?
≥2cm difference highly suspicious
List some low pretest probability for PE:
Age less than 50
Pulse rate less than 100 beats/min
Oxygen saturation greater than 94%
No hormone use
No hemoptysis
No unilateral leg swelling (measure with tape, NOT eyes)
No recent major surgery or trauma
No prior PE or DVT
What is a good predictor of the outcomes from PEs?
The degree of hypoxemia
One of the first workups we’re going to do in a suspected PE?
Pulse Ox
PE Workup – what Chest Xray finding is described below?
Increased opacity from intraparenchymal hemorrhage
Wedge-shaped density/area of infiltrate pointing towards hilum
Hampton’s Hump
PE Workup – what Chest Xray finding is described below?
Prominent central pulmonary artery with local oligemia
Unilateral lung oligemia (absence of vasculature)
Rare sign of a very large pulmonary embolism
Westermark’s Sign
What is the classic EKG finding in a PE?
T wave inversion in V1-V4
S1Q3T3: classic
This non-specific test can help confirm, but not diagnostic of a PE
D Dimer
What D-dimer level is strong evidence against thromboembolism?
less than 500
What screening test for a PE is 90% sensitive?
Venous ultrasound
What imaging is gold standard for diagnosing PE?
Pulmonary Angiography
Why is Pulmonary Angiography not commonly used for PE even though it is the gold standard?
Minimal use secondary to toxicity issues
Also invasive - must insert a catheter int the pulmonary artery and inject dye in the cath lab
What imaging has largely replaced Pulmonary Angiography for diagnosing PEs?
Helical (spiral) CT angiography
Which imaging used to be the gold standard – was the most useful screening tool to rule out PE?
Ventilation-Perfusion Scan
Which imaging is preferred for pregnant patients for evaluation of a PE?
Ventilation-Perfusion Scan
The prognosis of patients with pulmonary embolism depends on what 2 factors?
underlying disease state
appropriate diagnosis and treatment
Approximately what percentage of patients who develop PE die within the first hour?
10%
The mortality in patients with undiagnosed PE is what percentage?
30%
As a cause of sudden death, massive pulmonary embolism is second
only to what?
sudden cardiac death
Pathological state in which the systolic pressure in the PA is consistently elevated above normal
Pulmonary Hypertension
Most common cause of pulmonary hypertension is what?
left heart failure
Pulmonary circulation is unique because of what factors?
it’s high blood flow and low pressure and low resistance
What type of pulmonary HTN is most common?
secondary
Which type of pulmonary HTN is described below?
most common
Hypoxic vasoconstriction
Obliteration of pulmonary vasculature
Volume/pressure overload
Secondary Pulmonary Hypertension
Which type of pulmonary HTN is described below?
Rare (often genetic) - however cause unknown
Occurs mostly in young and middle aged women
Progressive dyspnea, rapid downhill course (self-perpetuates)
Invariably fatal if not treated – can be crippled within 6 months
Characteristic histopathologic plexiform lesions found in muscular
pulmonary arteries
Primary Pulmonary Hypertension
What signs may you hear on auscultation in pulmonary HTN?
Narrow splitting of second heart sound with accentuation of pulmonary component - P2 may be fixed or paradoxical splitting
Paradoxical splitting: splitting of S2 heard on expiration only (disappears during inspiration)
What are two of the biggest signs you may find on physical exam for pulmonary HTN?
RFV and Cor pulmonale
What is the is gold standard to confirm diagnosis of Pulmonary HTN?
Right heart catheterization
Right sided heart failure – enlargement of the right ventricle due
to high blood pressure in the arteries of the lungs usually caused by chronic lung disease
Cor Pulmonale
Cor Pulmonale is most commonly caused by what lung disease in the US?
COPD
What imaging is done to confirm the diagnosis of cor pulmonale?
Right heart catheterization
What heart rhythm is common to see in cor pulmonale and why?
Atrial fib/flutter
From RA dilation – the flimsiest chamber of the heart we have
