Respiratory Flashcards
What is a chylous effusion? When might you see it?
It is an exudate of chylomicron-rich fluid from the lymphatic duct that drains into the pleura due to damage by a tumor or trauma.
What is the most important antibiotic resistance mechanism of pseudomonas aeruginosa?
Mutation of a porin protein that restricts entry of antibiotics into the cell
What are three anaerobic species that are commonly aspirated from the oral cavity leading to aspiration pneumonia?
Bacteroides, Fusobacterium, and Peptococcus
In what medium does S. aureus cause color change to yellow?
mannitol salt agar
What is the most common cause of bronchiolitis in a 6 month old child?
RSV
How might one differentiate between lymphoma in the lungs and SCC?
SCC is of neuroendocrine origin, so it often presents with a paraneoplastic syndrome, such as Cushing’s
How does pertussis cause hypoglycemia?
Pertussis toxin ADP ribosylates Gi –> increased cAMP –> increased insulin production
What is the target for zileuton?
5-lipooxygenase
What is the molecule that binds to the CFTR channel, controlling the opening/closing?
ATP
What is the mechanism of asprin-induced asthma?
inhibits COX pathway w/out affecting LOX pathway → decreased ratio of prostaglandins:leukotrienes → bronchoconstrction in susceptible patients
What is the most common cause of lobar pneumonia?
Streptococcus pneumoniae causes 90-95% of cases. This is an alpha hemolytic organism that colonizes 40-70% of health individuals.
Describe the size and capsule of histoplasma capsulatum
small (2-5 um) yeast with thin cell wall but NO capsule
Where does cilia end in the respiratory tree?
terminal bronchioles contain cilated cuboidal epithelium–the alveolar ducts and alveoli are not ciliated
Where do goblet cells, glands, and cartilage generally stop in the respiratory tree?
at the end of the bronchi – bronchioles are just pseudostratified columnar ciliated epithelium until transitioning at the terminal bronchioles
What is the supposed cause of primary spontaneous pneumothorax?
Rupture of apical subpleural blebs, usually in tall, thin males around 20 y.o.
What is another name for the lung apex?
Superior sulcus
What are the abnormal serum values in sarcoidosis? What findings on bronchiolar lavage would help you differentiate sarcoidosis from hypersensitivity pneumonitis?
↑ ACE and Ca2+; you would see ↑ CD4:CD8 ratio
What is an alternative test to the sweat test for CF?
nasal transepithelial potential difference; if more negative than expected, evidence for CF b/c Na+ absorbed (these electrolyte changes occurs in most glands except sweat glands)
How does CF → hypovolemia?
NaCl loss in sweat
Does changing PaCO2 or PaO2 have more of an effect on cerebral vessel tone?
PaCO2
Do panic attacks cause hyper- or hypo- ventillation. How do the neurological symptoms relate?
hyperventilation → ↓ PaCO2 → vasoconstriction → dizziness, weakness, blurred vision
What is a quick and dirty HCO3- cutoff that would indicate the kidneys are holding onto bicarb in response to chronic respiratory acidosis? What time limits define acute and chronic respiratory acidosis?
30 suggests chronic
24 hrs chronic (compensation starts kicking in, max at 3-5 d)
What are the borders of the lungs at the:
- midclavicular line?
- midaxillary line?
- paravertebral line?
- 7
- 10
- 12
What cell secretes proteases and ROS that lead to alveolar wall destruction in emphysema?
neutrophils
