Clara cells
nonciliated cells in bronchioles that secrete component of surfactant and act as reserve cells. also degrade toxins
where aspirated objects go when upright vs supine
upright - lower portion of RLL
supine - superior portion of RLL
spatial relation of each pulm art to bronchus
RALS - right anterior, left superior
innervation of diaphragm
phrenic nerve (C3,4,5)
eqn for physiologic dead space in lungs
Vd = Vt * (PaCO2-PeCO2)/PaCO2 PaCO2 = arterial
at what lung volume is inward pull of lung and outward pull of chest wall balanced so that the pressure in the lungs is atmospheric?
FRC
which form of hemoglobin has higher affinity for O2 - taut or relaxed?
relaxed
5 things that dec Hgb affinity for O2
inc Cl, H, CO2, 2,3BPG, temp
methemoglobin
oxidized Hgb, inc affinity for cyanide
nitrites can cause it to form
tx for methemoglobinemia
methylene blue
tx of CN poisoning
give nitrites to make methemoglobin > binds CN and stops damage, use thiosulfate to bind CN forming thiocyanate > renally excreted
which way does Hgb binding curve shift when affinity dec?
right
which substances are diffusion limited vs perfusion limited in lung?
diffusion - O2 (in emphysema, fibrosis), CO
perfusion - O2 (in health), CO2, N20
nl pulm art pressure
10-14 mmHg
cause of primary pulm HTN
inactivating mutation of BMPR2 gene
cor pulmonale
right heart failure due to inc pulm resistance
alveolar gas eqn
PAO2 = PIO2 - PaCO2/R usually = 0.2*(770-20)-PaCO2/0.8 = 150 - PaCO2/0.8
nl A-a gradient
10-15 mmHg
causes of hypoxemia w/ inc A-a gradient
V/Q mismatch, diffusion limitation, R>L shunt
why does TB like the apex?
thrives in high O2 and apex has high V/Q ratio
haldane effect
oxygenation of Hgb > inc dissoc of H from Hgb > drives buffer system to favor production of CO2 > CO2 released from RBCs and exhaled
bohr effect
inc H from tissue metabolsim shifts Hgb dissociation curve to right and causes unloading of O2 into tissues
Virchow’s triad
stasis, hypercoag, endothelial damage
Homan’s sign
sign of DVT
dorsiflexion of foot causes calf pain
triad of hypoxemia, neuro abnlties, and petechial rash points to
fat embolism
best imaging choice for PE
CT pulm angiography
spirometry hallmark of obstructive lung dz
dec FEV1/FVC ratio
Reid index
thickness of gland : thickness of bronchial wall
>50% in chronic bronchitis
2 types of emphysema and what are they assoc w/
centriacinar (upper lobes) - smoking
panacinar (lower lobes)- alpha 1 antitrypsin def
Curschmann’s spirals
mucus plugs w/ shed epithelium seen in asthma
Charcot-Leyden crystals
make from breakdown of eos in sputum in asthma
inc ACE and Ca caused by what dz
sarcoidosis
3 pneumoconioses - who gets them and what lobes do they affect?
anthracosis - coal miners, upper
silicosis - foundries, sandblasting, mines. upper
asbestosis - shipbuilding, roofing, plumbing. lower
“eggshell” calcification of hilar LNs
silicosis
golden brown fusiform rods resembling dumbbells found in lung tissue
asbestos bodies
calcified pleural plaques
asbestosis
causes of ARDS
trauma, sepsis, shock, gastric aspiration, uremia, acute pancreatitis, amniotic fluid embolism
path process corresponding to ARDS
diffuse alveolar damage
formation of intraalveolar hyaline membranes assoc w/
ARDS
in what pulm condition do you find fremitus?
consolidation (lobar PNA, pulm edema)
leading cause of cancer death
lung CA
MC lung tumor
metastasis
where does lung CA metastasize to?
adrenals, brain, bone, liver
2 types of lung CA not assoc w/ smoking
bronchioloalveolar, bronchial carcinoid
MC type of lung CA in nonsmokers
adenoCA
mutation assoc w/ lung adenoCA
k-ras
bronchioloalveolar lung CA
type of adenoCA, limited to alveolar walls (appear thickened), excellent prognosis
3 assoc findings w/ SCC of lung
cavitation, hyperCA (from PTH-rp), keratin pearls
small cell lung CA - prognosis, assoc mutations, what cell started it
very poor
myc oncogenes
Kulchitsky cells
Kulchitsky cells
neuroendocrine cells that can turn into small cell lung CA
extra pulm manifestations of small cell lung CA
make ACTH, ADH, or ab against presynaptic Ca channels (Lambert Eaton syndrome)
large cell lung CA - prognosis
highly undifferentiated, poor prognosis. treated surgically
pancoast tumor
apical lung CA that causes Horner’s syndrome by interfering w/ cervical sympathetic plexus
bugs that cause bronchoPNA
strep pneumo, staph aureus, h flu, klebsiella
type of hypersensitivity for hypersensitivity pneumonitis
3/4
chylothorax
lymphatic pleural effusion. milky appearing fluid w/ inc TGs
what happens to cause spontaneous pneumothorax?
rupture of apical blebs
theophylline mech
inhib PDE > dec cAMP hydrolysis
blocks action of adenosine
corticosteroids used for asthma
beclomethasone, fluticasone
1st line therapy for chronic asthma control
inhaled corticosteroids
zileuton mech
5-lipoxygenase pathway inhib > block conversion of arachidonic acid to leukotrienes
omalizumab
anti-IgE, used in asthma resistant to inhaled steroids and LABAs
n-acetylcysteine - uses
mucolytic in asthma, antidote for acetaminophen overdose
bosentan - mech, use
antagonist to endothelin-1 receptors > dec pulm vasc resistance
pulm HTN