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192 Cards in this Set

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What differentiates COPD from asthma?
COPD is not fully reversible and progressive
What are the leukocytes that infiltrate lung parenchyma in COPD? (Pick all that apply)

neutrophils, eosinophils, lymphocytes, macrophages
neutrophils, macrophages and (CD8+) lymphocytes
What are the major inflammator mediators in COPD?
IL4, IL8 and TNF-a
What does alpha-1 anti-trypsin do in a healthy individual?
Protects the lungs from destruction by elastase (a protease carried by neutrophils)
Where is the major site of airway narrowing in COPD?
Small airways
What pattern of cellular damage is characteristic of alpha-1 antitrypsin related COPD?
alpha-1 antitrypsin = Panacinar - diffuse damage after terminal bronchioles
What pattern of cellular damage is characterised by smoking-related COPD?
smoking COPD affects proximal acinus: Centriacinar region (respiratory bronchioles) in irregular pattern
Why do COPD sufferers trap air?
The small airways become obstructed, leading to air trapping and eventually hyperinflation
What causes pulmonary hypertension in COPD patients?
Chronic hypoxia leads to vascular remodeling
What might account for COPD being associated with CVD?
Lung inflammation may upregulate systemic inflammation, destabilizing vascular endothelium and plaques
What type of COPD is associated with "blue bloaters?"
Chronic bronchitis - tend to be hypoxic and overweight. More V/Q mismatch
What type of COPD is associated with "pink puffers?"
Emphysema - less hypoxic and better V/Q match, but dyspnea is noticable
What lung function results would you expect to see in COPD?
FEV1/FVC <70%
FEV1 determines stage:
100-80 = mild
50-80 = moderate
30-50 = severe
<30 = very severe
When would you order arterial blood gas for a COPD patient?
For a type B (chronic bronchitis), or moderate/severe disease
What Ig is linked to asthma/exzema?
IgE
What is the difference between intrinsic and extrinsic asthma?
Intrinsic is lifelong with chronic inflammation between attacks.
Extrinsic has a precipitating factor and acts like allergy (goes away with precipitator)
What is the asthma triad?
Bronchospasm
Edema
Hypersecretion of mucus
Which of the asthma triad is associated with late phase vs. early phase?
Late stage: airway edema (hyperresponsiveness)
Early stage: bronchospasm, mucus secretion
Why is asthma obstructive?
Airways open on inspiration, but tend to collapse on expiration
Why does tachypnea worsen asthma symptoms?
Air is trapped because of obstructed airways. Asthmatic wants to expel leftover dead air, but its getting hypoxic, so breathes faster. This lessens time for exhalation, exacerbating air trapping and hypoxia.
What blood test finding would be suggestive of asthma?
Eosinophilia, elevated IgE
What is a methacholine challenge test?
For asthma - give doses of methacholine (bronchoconstrictive) until FEV1 reduced by 20% from baseline. Small # doses = might be asthma. Lots of doses, probably not asthma.
What 2 common disease are linked with asthma?
Allergic rhinitis, GERD
Why is helium/oxygen helpful in an acute asthma attack?
Helium is less dense and viscous than Nitrogen. Helps get O2 into lungs and push CO2 out.
What tx are first line for acute asthma?
Albuterol, steroids, O2 /vent if needed
What are the severity stages of asthma?
1a. Mild intermittent (</=2/week, 2/month at night)
1b. Mild persistent (>2/week but not daily, >2/month at night)
2. Moderate persistant (daily sx and use of rescue inhaler, >1/week at night, exacerbations >2/week, obstruction on PFTs)
3. Severe persistent (continuous sx and frequently at night)
What viruses predominate in wheezing children under 2 vs. 2 or older?
RSV <2
Rhinovirus >/=2
When are asthma hospitalizations highest?
When school is in session and when there are respiratory viral infection outbreaks
What viruses are associated with protection vs. increased risk for asthma?
2 common colds before age 1 = protection

1 lower-respiratory tract infection with wheeze before age 3 = increased risk
What receptor may be faulty in some asthmatics?
glucocorticoid receptor may be mutated (GCR-beta) - leading to steroid insensitivity because it does not bind well to DNA and induce downstream effects of steroids
In the hygiene theory for asthma, different T cells mediate chronic infection vs. parasite responses. Which type of T cell is associated with each?
TH1 = chronic infection: TNF, IFN, IL2

TH2 = parasites: IL4,5,6,10,13
What is shunt, and what conditions cause it?
Pulmonary shunt: blood never gets to air: Filled or collapsed alveoli

Vascular shunt: AV malformation or patent FO
What is V/Q mismatch, and what conditions cause it?
Ventilation and perfusion of blood are not well matched: ILDs/fibrosis, COPD, dead space, PE - overdistention and compression of capillaries
What is meant by "won't breathe" vs. "can't breath?"
Won't breath is hypoventilation when the subject isn't working hard = drugs, ideopathic, hypothyroid

Can't breath is when the subject is working hard but can't overcome increased work, get fatigued, as in COPD, ILD, NMD
Explain Shunt vs. Dead space on the V/Q spectrum
Shunt is where there is no chance for air to get to the blood (Pneumonia/atelectasis)

Dead space is perfused alveoli with no perfusion (PE)
Why does V/Q change from top to bottom of the lung?
Due to perfusion (Q). Low V/Q due to high Q at base of lungs.
High V/Q due to low Q at apex of lungs
What causes improvement of V/Q mismatch in pneumonia (shunt)?
Hypoxia turns on K+ pump, opens Ca++ channels which cause vascular smooth muscle to contract, diverting blood away from shunted alveoli.
What causes improvement of V/Q mismatch in PE (dead space)?
Fibrous bands surrounding alveoli sense lack of perfusion via lack of CO2. Contract around dead space alveoli, decreasing compliance and diverting air to areas with good Q.
What is associated with DECREASED DLCO?
Emphysema, parenchymal disease, vascular disease and anemia
What is associated with INCREASED DLCO?
Asthma, pulmonary hemhorrhage, polycythemia, L-R Shunt
Where in the lungs are centrilobular emphysematic lesions prominently found?
Apices
When would you expect to see distal acinar emphysema?
Adjacent to scarring - causes pneumothorax in otherwise healthy young people
When would you expect to see irregular acinar distribution of emphysema?
Incidentally in an autopsy of an elderly person - least clinically significant emphysema
What is the hallmark pathology behind chronic bronchitis?
Excess mucus secretions in large airways, produced as a response to irritants/infection
What are the cellular features here typical of chronic bronchitis?
Thickened mucus gland layer
Squamous metaplasia
What is the Reid index for mucosal gland size, and what is it used for?
Reid index is mucosal gland thickness / thickness of bronchial wall to cartilage.

>.4 indicates chronic bronchitis
Is asthma associated with TH1 or TH2 lymphocytic response?
TH2 - acute parasite response instead of chronic response
What is the prominent Immunoglobulin of asthma?
IgE
What is the prominent leukocyte of asthma?
Eosinophils
What do eosinophils release in asthma that is damaging to epithelium and causes late phase bronchoconstriction?
Major basic protein
What is wrong with this picture from an asthmatic?
ASTHMA:

Neutrophils and macrophages, thickened basement membrane, extra mucus secretions
What lab tests for diagnosing asthma are helpful in sputum samples?
Charcot-Leyden crystals (Eosinophil product), Curschmann spirals (mucus)
What is bronchiectasis, and what causes it?
Chronic infections of the bronchi with permanent dilation:
Obstruction: Tumors, foreign bodies
Hereditary:
CF
Intralobar sequestration
Immotile cilia
Immune deficiency
Pneumonia: Staph or TB
What two insults are required for bronchiectasis?
Obstruction and infection:

Inflammatory response causes dilated airways, which eventually becomes irreversible
What is evident on gross examination?
Bronchiectasis - dilated airways with thin walls, areas of necrosis (This is a CF case)
What did the owner of these lungs have?
CF, with pseudomonas aeruginosa causing green discoloration. Note prominent dilated airways and mucus plugging.
What is the Alveolar gas equation
PaO2 = FiO2 x (Barometric pressure - PH20 vapor) - PACO2 / R

= .21 (at room air)x(760 - 47) - Palveolar CO2 / .8
What does alveolar hypoxia induce in pulmonary arterial supply?
Vasoconstriction, increasing resistance and pulmonary arterial pressure
What are the short term physiologic responses to altitude?
Increased minute ventilation
Increased 2,3 DPG in RBCs (to cause hypoxic RBCs to release O2)
Increased hemoglobin
Compensated respiratory alkalosis
What are the long term physiologic responses to altitude?
Decreased response to hypoxia
Increased DLCO, Increased vascularity of heart and muscles
At what height does mountain sickness occur?
Above 3000 feet above sea level
What are symptoms of mountain sickness?
Hangover: headache, n/v malaise
What are the triggers for anion-gap metabolic acidosis?
MUDPILES
Methanol
Uremia
DKA
Paraaldehyde
Isoniazid
Lactic acidosis
Ethylene glycol
Salicylates
What is the equation to determine if an anion-gap acidosis is compensated?
If compensated:
PCO2 = 1.5 (bicarb) +8
How do you calculate serum osmolarity?
2xNA + Glucose / 18 + BUN/2.8
What is a normal anion gap?
10-14
What organism type causes an interstitial pattern of infection?
Viral
What leukocyte infiltrate is pneumonia characterised by?
Polys
What is seen here? The patient had pneumonia.
Interstitial fibrosis, fibrotic tissue in airspaces from incomplete resolution of pneumonia
What bugs are community acquired pneumonia most commonly caused by?
SHPKV
Strep pneumo (1)
H Flu
Pseudomonas
Klebsiella
Viral
What is pictured here? This is from a 6 month old baby with consolidation on CXR.
RSV pneumonia
What is seen here? The patient had received a liver transplant 10 months prior.
CMV pneumonia
What is seen here? The patient had a cold followed by pneumonia.
Adenovirus pneumonia - chronic inflammation, congestion and hemhorrhage
What is seen here, possibly caught in the Mississippi or Ohio River valleys?
Histoplasmosis ball in lung
What infection is seen here, possibly caught in the San Joaquin Valley?
Coccidiomycosis - note non-budding spherule with endospores
What fungal infection is seen here?
Blastomycosis - from Mississippi valley. Broad based buds, nuclei apparent unlike in other fungi
What fungus can colonize a hole left by another disease?
Aspergillus - aspergilloma in a TB or tumor cavity
What fungus has near right-angle branching of non-septated hyphae?
Mucormycosis
What is represented here, staining black on GMS?
PCP (pneumocystis jiroveci), only a problem in immunocompromised
What is solute component in healthy vs. CF mucus?
3% healthy
up to 15% CF
Solute level affects function
What are the main antimicrobial functions of mucus?
Bacteriostatic (iron binding)
Bactericidal (Lysozymes and defensins)
Opsonizing (Complement, ficolins, collectins)
What are the two layers of airway mucus?
Sol (acqueous, cilia move freely)
Gel (viscous, traps particals and is beaten by cilia toward the head)
What is the normal arrangement of microtubules in respiratory cilia?
9+2 doublets
What non-ciliary abnormality (i.e., not infertility) is associated with primary ciliary dyskinesia?
situs inversus
What may happen with aging that impairs mucociliary elevator function?
microtubular disarrangement, impairing coordinated ciliary beating
Why do the elderly have impaired humoral immunity
Loss of Th cells (B cells largely are unaffected by aging)
What is the protein mutated in Cystic Fibrosis?
CFTR, which regulates Cl secretion, causing viscous mucous
What are reasons that cough can fail?
Muscular weakness (cervical injury - expiratory, diaphragm weakness - inspiratory)
Mucus problem (CF)
What mutation is associated with recurrent gram-negative bacterial infections?
TLR4 receptor on macrophages (PAMP for lipopolysaccharide)
What cell cleans up excess surfactant?
Macrophages
What causes pulmonary alveolar proteinosis?
Alveolar macrophage defect, leaving surfactant undigested and filling in alveoli, causes dyspnea and hypoxia (shunt)
What kinds of infections are people with Pulmonary alveolar proteinosis predisposed to?
Atypical, ex: nocardia, fungi
What is the role of surfactant proteins A and D in immune response?
Surfactant A/D are the collectins (opsonization). Inhibit macrophage phagocytosis, tend to down-regulate inflammation
Where is bronchus-associated lymphoid tissue most commonly found? (BALT)
At bifurcations
What is a neutrophil NET?
Extracellular trap - meshwork of antimicrobial proteins that the PMN spits at an enemy
What does chronic granulomatous disease cause in long term?
Bronchiectasis and fibrosis
What sort of cough does an interstitial lung disease produce?
Dry (alveolar damage is distal to mucociliary elevator)
What is the clinical name that encompasses all these pathological terms:
Usual interstitial pneumonitis, Desquamative IS pneumonitis,
Bronchiolitis Obliterans-Organizing pneumonia
Idiopathic pulmonary fibrosis
Of all the idiopathic pulmonary fibroses, which should you separate from the others for dx/ treatment purposes:

Usual ISP
Desquamative ISP
Lymphocytic ISP
Giant cell ISP
Bronchiolitis ISP
Bronchiolitis Obliterans - Organizing Pneumonia
Separate Usual ISP from all others, because it is usually fatal and does NOT respond to steroids

All the others respond to steroids and are not typically fatal
Why don't steroids help usual interstitial pneumonitis/ idiopathic pulmonary fibrosis?
It is a fibrosing disease, not an inflammatory disease
What can you expect to see on a gross specimen of UIP/IPF?
Holes as in emphysema, but fibrosis surrounding (honeycombing). Heterogeneous pattern with some healthy areas.
What typical feature of UIP/IPF is seen here?
A fibroblastic focus, will develop into UIP/IPF
What stage of UIP is seen here?
End stage - fibrosis with epithelium lined cavities
What might you expect to see in a non-specific interstitial pneumonitis on gross inspection that would be different from UIP/IPF?
On gross, UIP/IPF is heterogenous: some of the lung will appear normal, while other areas are destroyed.

NSIP is more homogenous, the whole lung will look pretty similar on gross
In what areas of the lungs do you typically see greater involvement for non-specific IPF?
Upper lobes
What behavior is linked with desquamative interstitial pneumonitis?
Smoking
What leukocytic infiltrate is seen here in desquamative interstitial pneumonitis?
Alveolar macrophages
What is the difference between desquamative ISP and bronchiolitis?
They are similar, both associated with smoking, but bronchiolitic macrophages are concentrated at bronchioles instead of alveoli
What is anthracosis?
Carbon dust in lung - seen in coal miners and some urban residents. Asymptomatic and hardly a disease
What is the difference between anthracosis and simple coal workers pneumoconiosis?
CWP is a step up from anthracosis. May also be asymptomatic, but associated with emphysema.

CWP get macules (1-2mm) and nodules (larger) - aggregates of pigment and macs
What would you expect this patient's work history to include?
Coal miner
To what vascular disease does progressive massive progress?
Pulmonary hypertension, cor pulmonale
Apart from the black pigment, what finding is typical of PMF?
collagen (stains pink)
What is silica's main effect in the lung?
Fibrogenic
Besides coal mining, what exposure can cause PMF?
Silica (sand) exposure - Black lung without the black
What happens after silica is inhaled that causes fibrosis?
Macrophages attempt to digest silica, but die instead. Necrosis attracts fibrogenic mediators. In the process, the silica is released and another macrophage tries to eat it.
What pulmonary function changes would you expect to see in someone with a pleural plaque?
None - sometimes an incidental finding, and only indicates asbestos exposure, not disease.
What differentiates asbestosis from pleural plaques?
Asbestosis is an actual disease. Ferruginous bodies, and diffuse interstitial fibrosis
What pulmonary function changes would you expect to see in someone with a pleural plaque?
None - sometimes an incidental finding, and only indicates asbestos exposure, not disease.
What differentiates asbestosis from pleural plaques?
Asbestosis is an actual disease. Ferruginous bodies, and diffuse interstitial fibrosis
What feature typical of hypersensitivity pneumonitis can you see here?
Inflammatory infiltrate at airways, which can progress to fibrosis.

Other feature is non-caseating granulomas
What is the prominent cell in a TB focus?
Epithelioid histiocyte (macrophage)
How does TB reactivate?
When a focus of necrosis extends into the bronchial tree, producing a contagious cough
What does the pattern of growth suggest about the type of cancer seen here?
Lepidic growth - adenocarcinoma is growing along the alveoli using it as scaffolding. This may present not as a mass, but appear to be pneumonia
What mutation is associated with non-mucinous adenocarcinoma of the lung?
EGFR (non-smoker type)
What mutation is associated with mucinous adenocarcinoma of the lung?
K-RAS (smoker type)
What is Horner's syndrome?
eyelid drop (ptosis) anhidrosis, meiosis due to cervical sympathetic nerve invasion by a pancoast tumor
What tumor has cavitary, central presenting lesions with HIGH CALCIUM
squamous cell carcinoma
What type of cancer may present with myasthenic syndrome?
Small Cell LC - cancer produces antibodies to calcium channels
What is the pattern of the lesion seen here, and what is it likely to be?
Popcorn lesion, likely to be hamartoma
What is a spiculated border suggestive of on a pulmonary nodule by CT?
Malignancy
What is wrong with this picture?
Pulmonary edema
What are alveolar macrophages filled with in pulmonary edema?
hemosiderin (blood biproduct)
What is the different between exudate and transudate?
Exudate has protein, cells
Transudate is serum only
What specifically is damaged in diffuse alveolar injury (DAD)?
capillary endothelium, alveolar epithelium or both
Why is surfactant lost in diffuse alveolar damage?
The Type II pneumocytes are damaged and stop producing surfactant
What do macrophages release to recruit neutrophils to the sites of diffuse alveolar damage?
IL-8
What stage of interstitial edema is this?
Early - but still greater distance for O2 to travel
What are hyaline membranes composed of?
Protein, fibrin, and necrotic epithelium
What causes transfusion-related acute lung injury?
plasma products that contain antibodies to leukocytes from the donor
What lung condition is scleroderma associated with?
PH
What disease is associated with BMPR2 (bone morphogenetic protein receptor) mutations?
Primary pulmonary hypertension, AR with incomplete penetrance
What two features characteristic of pulmonary hypertension are seen here?
Intimal thickening, and a plexiform lesion (at bottom)
What do lines and dots in the base of lungs on CXR indicate? Patient also has dry crackles.
Interstitial disease
What is this, and what are depicted in the periphery?
A non-caseating granuloma of sarcoidosis. Epithelioid histiocytes are at periphery
What cell marker gets depleted in sarcoidosis peripheral blood?
CD4 cells
Sarcoidosis elevates serum levels of 2 substances. Which ones?
Vitamin D (=hypercalcemia and hypercalciuria)
ACE
What do lines and dots in the base of lungs on CXR indicate? Patient also has dry crackles.
Interstitial disease
What would you expect to find on the CXR of this patient?
Hilar/mediastinal lymphadenopathy, and interstitial lung infiltrates.

Sarcoidosis
Why is PEEP ventilation good?
Keeps alveoli open, so you can decrease O2 sat and prevent O2 injury
Why is PEEP ventilation bad?
Ventilation causes trauma, and reduces cardiac output
What cells become hyperplastic in recovery of ARDS?
Type II pneumocytes
When would you set PEEP higher than 5mmHg H20?
For someone who was morbidly obese, or with airspace disease bilaterally
What are the cornerstones of TB DOT therapy?
Political will
Standardized Tests
Standardized Tx
Uninterrupted drug supply
Workers to observe patients take drug
What would a D-dimer help you diagnose?
Coagulopathy - thrombus forming likely.

If D-dimer negative, probably not PE
When would you use a IVC filter?
For a patient with DVT/PE who cannot receive anticoagulants
How much time is spent in REM vs. non REM sleep?
20-25% REM
How long is the sleep cycle?
90 min
Do you get the bulk of REM sleep at the beginning or end of a sleep episode?
More at the end
When awake with eyes closed, what EEG rhythm predominates?

alpha
beta
gamma
theta
alpha waves in awake with eyes closed
At sleep onset, what EEG wave form predominates?

alpha
beta
gamma
theta
theta waves at sleep onset
What sleep stage is characterised by slow rolling eye movements on EOG (electrooculography), and switch to theta waves?
N1
What sleep stage is characterised by sleep spindles and K waves?
N2 - where you spend about half of a good night's sleep
What are delta waves?
Slow wave sleep - N3
Is REM characterised by regular or irregular breathing?
Irregular breathing
What level of sleep is characterised by saw-tooth waves?
REM
What is the function of the suprachaiasmatic nuclei of the hypothalamus?
Biological clock for circadian rhythms
How does the SCN of the hypothalamus get information about light/dark conditions?
From the retina through the retinohypothalamic tract (RHT)
What autonomic nervous system predominates during non REM sleep?
Parasympathetic (Rest and Digest)
What autonomic nervous system predominates during REM sleep?
Parasympathetic, with some sympathetic incursions
What sleep neurotransmitters promote REM vs. NREM?
promotes REM - acetylcholine
inhibits REM - GABA, adenosine, serotonin
What happens to the hypercapnia/hypoxia response during sleep?
Gets blunted
What happens to delta waves in SWS with age?
Gets blunted
What is Pickwickian syndrome?
Hypoventilation related to obesity - hypercapnia also while awake
What is Congenital central hypoventilation syndrome?
Blunted response to hypercapnia while awake, absent during sleep.

Ondine's curse
How many incidents of apnea/hypopnea per hour are required to designate obstructive sleep apnea syndrome?
at least 5/hour
What kind of patient would exhibit Cheyne-Stokes respiration during sleep, in which they would breath quickly followed by periods with apnea?
Heart failure - brain isn't getting enough blood and doesn't know you're hypoxic yet. Then has to breathe rapidly to catch up
Why is acetazolamide helpful for central sleep apnea?
It acidifies blood, making chemoreceptors kick in respiratory drive
All of the following are characteristics of N2 sleep EXCEPT:
a) Comprises most sleep across the night
b) K-complexes
c)Delta waves
d) Sleep spindles
e) 12-14 hz eeg
Delta waves
The neurotransmitter most implicated in generating REM sleep is:
a) norepinephrine
b) acetylcholine
c) dopamine
d) serotonin
e) histamine
acetylcholine
Response to hypercapnia is lowest during:
a) wakefulness
b) N1
c) NREM
d) slow wave sleep (N3)
e) REM
REM
59 y/o woman with loud snoring, BMI=33.7 kg/m2, daytime fatigue, AHI = 4.8 events/hr, ABG on room air: pH=7.34; PO2=38 mm Hg; PCO2=65.8 mm Hg; SaO2 =68 %
Cheyne-Stokes Respiration
Central Sleep Apnea
Obesity Hypoventilation Syndrome
Obstructive Sleep Apnea
Ondine’s Curse
Obesity hypoventilation syndrome
47 y/o man with loud snoring, BMI=23.8 kg/m2, daytime fatigue, AHI = 11.8 events/hr on his side & 18.3 supine, ABG on room air: pH=7.39; PO2=92 mm Hg; PCO2=41 mm Hg; SaO2 =99%
Cheyne-Stokes Respiration
Pickwickian Syndrome
Obesity Hypoventilation Syndrome
Obstructive Sleep Apnea
Primary snoring
Obstructive sleep apnea
47 y/o man with loud snoring, BMI=23.8 kg/m2, daytime fatigue, AHI = 11.8 events/hr on his side & 18.3 supine, ABG on room air: pH=7.39; PO2=92 mm Hg; PCO2=41 mm Hg; SaO2 =99%.
Which of the following is NOT an appropriate treatment?
CPAP
Tracheostomy
Nasal steroids
Body position training
Mandibular advancement device
Tracheostomy
Which layer of the pleura is drained by pulmonary veins?
Visceral pleura
What are the two main causes (and types) of pleural effusion?
Disrupted membrane = exudate (Infection)
Altered driving pressure = transudate (CHF, cirrhosis, nephrosis)
What is the proximal cause of hepatic hydrothorax?
Ascites (though may not be apparent) as results from liver disease
What is the cause of empyema?
A lung infection near visceral pleura, which causes pus to leak into pleural space. Must be drained!
What happens to percussion and breath sounds with pleural effusion?
Dullness, decreased breath sounds
Why is a loculated pleural effusion alarming
When the effusion does not follow gravity, it's probably larger and more viscous/solid than a transudate
What are Light's criteria and what are they used for?
Used to decide whether pleural fluid is transudate or exudate.

1. Pleural lactate dehydrogenase is >.6 of serum LDH
2. Pleural LDH is in upper 2/3 of normal serum level
3. Pleural protein is >.5 of serum protein

If any one of these is true, fluid is exudate
Under what pH do you consider a pleural effusion complex?
<7.2 pH = complex pleural effusion