Pulm

Question 1

Structures cross the diaphragm at what levels

Answer 1

I ate 10 eggs at 12

• IVC - T8
• esophagus - T10
• aorta - T12

Question 2

physiologic dead space equation

Answer 2

Vd = Vt x (PaCO2 - PeCO2)/PaCO2
taco, paco peco, paco
= tidal volume (arterial PCO2 - expired air PCO2)/arterial PCO2

Question 3

things that favor the taught form of Hgb

Answer 3

Cl-, H+, CO2, 2,3BPG and temperature

- right shift favored by BAT ACE: BPG, altitude, temp, acid, CO2, exercise

Question 4

methemoblobin

Answer 4

• oxidized Hgb (Fe3+), doesnt bind Hgb as well, seen in newborns and with oxidative stress (cyanosis and chocolate covered blood)
• binds cyanide well, so give nitrites to form methemoglobin in cyanide poisoning, then give thiosulfate to bind cyanide and be renally excreted

Question 5

carboxyhemoglobin

Answer 5

CO binds Hgb, causes a left shift and pts have cherry red skin

Question 6

perfusion limited vs. diffusion limited

Answer 6

• perfusion limited: things that are perfusion limited equilibrate early: O2 in healthy ppl, CO2, N2O
• diffusion limited: things that do not equilibrate by the time the blood reaches the end of the capillary: O2 in emphysema and fibrosis, CO

Question 7

hypoxemia with normal Aa gradient

Answer 7

high alt, hypoventilation

Question 8

hypoxemia with increased Aa gradient

Answer 8

VQ mismatch, diffusion limitation, RL shunt

Question 9

V/Q = 0

Answer 9

shunt

- does not improve with 100% O2

Question 10

V/Q = infinity

Answer 10

blood flow obstruction

- does improve with 100% O2

Question 11

Haldane effect

Answer 11

oxygenation of Hgb promotes dissociation of H+ from Hgb, therefore CO2 is released

Question 12

Bohr effect

Answer 12

increased H+ in the tissue causes a right shift, causing unloading of O2

Question 13

response to high altitude

Answer 13

decreased PaO2 leads to hyperventilation

• increased EPO
• increased 2,3BPG for more O2 unloading
• more renal excretion of bicarb to compensate for respiratory alkalosis

Question 14

response to exercise

Answer 14

increased CO2 production and O2 consumption

• increased ventilation rate, and V/Q becomes more uniform throughout the lung
• no change in PaO2 and PaCO2, but increase in venous CO2 and decrease in venous O2 content

Question 15

rhinosinusitis bugs

Answer 15

S. pneumo, H flu, M catarrhalis

Question 16

virchow triad

Answer 16

• predisposition to DVTs

- stasis, hypercoagulability, endothelial damage

Question 17

different types of emboli and their classic findings

Answer 17

• fat: hypoxemia, neurologic abnormalities and petechial rash
• amniotic fluid: DIC
• gas: divers, treat with hyperbaric O2

Question 18

centriacinar vs. paracinar emphysema

Answer 18

• centri - smokers

- para - alpha 1 antitrypsin

Question 19

asthma path findings

Answer 19

Curschman spirals (shed epithelium forms mucus plugs)
Charcot-Leyden crystals (formed from breakdown of eosinophils in sputum)

Question 20

bronchiectasis

Answer 20

• chronic necrotizing infection of bronchi –> permanently dilated airways, purulent sputum, recurrent infections and hemoptysis
• assoc w/ bronchial obstruction, poor ciliary motility (smoking), Kartagener syndrome, CF, allergic bronchopulmonary aspergillosis

Question 21

asbestosis findings and increased risks

Answer 21

• asbestos (ferrunginous) bodies are golden-brown fusiform rods resembling dumbells
• increased incidence of bronchogenic carcinoma and mesothelioma

Question 22

silicosis findings

Answer 22

• impairs macrophages, leads to fibrosis and increased susceptibility to TB
• “eggshell” calcification of hilar lymph nodes

Question 23

pulm HTN

Answer 23

• primary due to BMPR2 gene, leading to vascular smooth muscle cell proliferation, poor prognosis
• secondary due to COPD, VTE, AI disease, L-R shunt, sleep apnea or high alt

Question 24

most common sites that metastasize TO the lungs

Answer 24

breast, colon, prostate, bladder

Question 25

most common sites that the lungs metastasize to

Answer 25

adrenals, brain, bone, liver

Question 26

lung adenocarcinoma

Answer 26

- most common - peripheral - activating mutations include k-ras, EGFR, and ALK - clubbing

Question 27

squamous cell carcinoma of the lung

Answer 27

- Central, Cavitation, Cigarrettes, hyperCalcemia (PTHrP) - SCa+++mous - keratin pearls and intercellular bridges

Question 28

small cell (oat cell) lung cancer

Answer 28

- central, undifferentiated, aggressive - Acth, Adh, Antibodies (Lambert-Eaton), Amplification of myc - inoperable, treat with chemo - neoplasm of the neuroendocrine Kulchitsky cells --> small dark blue cells

Question 29

large cell carcinoma

Answer 29

- peripheral - highly anaplastic undiff tumor, poor prognosis - removed surgically - pleomorphic giant cells

Question 30

bronchial carcinoid tumor

Answer 30

- excellent prognosis - symptoms due to mass effect, occasionally carcinoid syndrome (flushing, diarrhea, wheezing) - nests of neuroendocrine cells, Chromagranin A +ve

Question 31

mesothelioma

Answer 31

- malignancy of the pleura with hemorrhagic pleural effusions and pleural thickening - psammoma bodies

Question 32

pancoast tumor

Answer 32

- Horner, SVC, sensorimotor defects, hoarseness, upper extrem edema

Question 33

transudate pleural effusion

Answer 33

low prot content | - CHF, nephrotic syndrome, hepatic cirrhosis

Question 34

exudate pleura effusion

Answer 34

high prot content | - malignancy, infection, collagen vascular disease, trauma

Question 35

lymphatic pleural effusion

Answer 35

- milky fluid with high TG | - thoracic duct injury

Question 36

1st gen H1 blockers

Answer 36

- diphenhydramine, dimenhydrinate, chlorpheniramine - used in allergy, motion sickness, sleep aid - tox - sedation, antimuscarinic, anti-adrenergic

Question 37

2nd gen H1 blockers

Answer 37

- loratidine, fexodenadine, desloratidine, cetirizine - used in allergy - tox - less sedating because less CNS penetration

Question 38

guaifenesin

Answer 38

expectorant - thins resp secretions, does not suppress cough reflex

Question 39

NAC

Answer 39

mucolytic - can loosen mucous plugs in CF kids

Question 40

dextromothorphan

Answer 40

- antitussive (NMDA antagonism) - synthetic codeine analog - mild opioid effect in excess, mild abuse potential - naloxone can be given for overdose

Question 41

pseudoephedrine, phenylephrine

Answer 41

- alpha agonist nasal decongestants - reduce hyperemia, edema and nasal congestion - tox - HTN, can also cause CNS stimulation/anxiety - tachyphylaxis - rapidly declining effect after a few days due to decreased production of norepi at nerve terminals

Question 42

b2 agonists

Answer 42

- albuterol (short), salmeterol, formoterol (long-acting) - relaexes smooth muscle - SE: tremor and arrhythmia

Question 43

theophylline

Answer 43

- methylxanthine that causes bronchodilation by inhibiting PDE --> inc CAMP because of decreased breakdown - narrow TI, p450 metabolizes it, blocks adenosine actions

Question 44

beclomethasone, fluticasone

Answer 44

corticosteroids that inactivate NFkB, the transcription factor that induces the production of TNFa and other inflammatory cytokines

Question 45

monteleukast, zafirlukast

Answer 45

leukotriene receptor blocker, good for aspirin-induced asthma

Question 46

zileuton

Answer 46

5-lipoxegenase pathway inhibitor (blocks AA --> leukotriene conversion)

Question 47

omalizumab

Answer 47

monoclonal IgE Ab for allergic asthma

Question 48

bosentan

Answer 48

used to treat pulmonary arterial hypertension, competitively antagonizes endothelin-1 receptors, decreased pulmonary vascular resistance