Pulmonary Vascular Disease and Pleural Disease (PATHOLOGY) Flashcards
Why is atherosclerosis not common in the pulmonary circulation?
because it is a Low pressure system
What is pulmonary oedema?
Accumulation of fluid in the lung interstitium and/or alveolar spaces
Leaking of fluid into interstitium causes it to ______ resulting in which kind of spirometry pattern?
thicken
Restrictive
What are the causes of pulmonary oedema?
Increase in hydrostatic pressure
Cellular injury to alveolar lining or alveolar endothelium
What can cause ARDS?
Sepsis
Diffuse infection
Severe trauma
Oxygen (if at toxic levels)
What is the pathological cause of ARDS?
Injury to alveolar lining or epithelium leading to infiltration of inflammatory cells, release of inflammatory cytokines, oxygen free radicals and injury to cell membranes
What would you expect to find on autopsy of a patient that suffered from ARDS?
Fibrinous exudate lining of alveolar walls
Cellular regeneration
Inflammation
What are the 3 outcomes for ARDS?
Death
Resolution
Fibrosis
Why can low levels of surfactant in neonates cause RDS?
Increased effort to expand the lungs can lead to physical damage to the cells
What is an embolus?
A detached intravascular mass carried by the blood to a site in the body distant from its point of origin
What is meant when saying that many PEs are subclinical?
Patient doesn’t really know that they are occurring
What is the most common site or origin for PEs?
DVT of lower limbs
Why are DVTs of the lower limbs common?
We stand a lot so there is a high hydrostatic pressure
Why are long-haul flights a risk factor for DVTs?
Blood isn’t pumped properly
Virchow’s triad describes the risk factors for PEs. What are these?
Factors in endothelial wall (e.g. endothelial hypoxia)
Abnormal blood flow (venous stasis)
Hyper coagulate blood (e.g. cancer or post-MI patients due to high platelet levels)
What are the effects of PEs?
Sudden death Severe chest pain Dyspnoea Pulmonary hypertension Pulmonary infarct (leading to...) Haemoptysis
What do the effects of PEs depend on?
Size of embolus
Cardiac function
Respiratory function
What are the common features of small PEs?
more likely to cause chronic effects like pulmonary hypertension
Clinically silent
What are the common features of large PEs?
Death
Pulmonary infarct
Severe symptoms
What causes pulmonary infarct?
PE + Compromised bronchial artery supply
What type of patient typically gets primary pulmonary hypertension?
Young women
How common is primary pulmonary hypertension?
No, it is very rare?
What causes primary pulmonary hypertension?
Idiopathic (unknown)
What causes secondary pulmonary hypertension?
Hypoxia (vascular constriction leading to pressure increase)
Increased pulmonary blood flow (congenital heart disease)
PE
Emphysema Back pressure from left-sided heart failure
What is the morphology of pulmonary hypertension?
Medial hypertrophy of arteries Intimal thickening (fibrosis) Atheroma Right ventricular hypertrophy If extreme - plexogenic change/necrosis
What is cor pulmonale?
Pulmonary hypertension complicating lung disease
Describes changes in the right ventricle = RV hypertrophy / RV dilation / right heart failure
What is the pleura?
Mesothelial surface lining the lungs and mediastinum
What are the mesothelial cells in the pleura designed for?
Fluid absorption
What is the hallmark of disease in the pleura?
Effusion
What are the two types of pleural effusions?
Transudate (low protein)
Exudate (high protein)
Between transudate and exudate pleural effusion - which one in active and which one is a passive process?
Transudate - passive
Exudate - active
Which diseases are associated with transudate pleural effusion?
Cardiac failure
Hypoproteinaemia
Which diseases are associated with exudate pleural effusion?
Pneumonia
TB
Connective tissue disease
Malignancy
What is a purulent effusion?
Full of acute inflammatory cells = pus = Empyema
Can become chronic
Empyema usually occurs as a complication of ______
pneumonia
What is a pneumothorax?
Air in the pleural sapce
What can cause a pneumothorax?
Trauma
Rupture of bulla
What is a malignant primary neoplasm in the pleural space?
Malignant mesothelioma
What is the common secondary neoplasm in the pleural cavity?
Adenocarcinomas from the lung GI tract or ovary
What chemical are mesotheliomas related to ?
Asbestos exposure
What cell differentiation do malignant mesotheliomas have?
Mixed epithelial and mesenchymal differentiation
How can malignant effusions be diagnosed
Fluid form effusion sent to pathology - examine cytology
Sometimes requires bigger piece or biopsy
Immunohistochemistry for lineage specific antigens
Medicolegal important
How does immunohistochemistry work and what is it used for?
Can identify primary/secondary and benign / malignant using different antibodies
