Pulmonology Flashcards
What is surfactant (chemically)?
Dipalmitoyl phosphatidylcholine
What is the shape of Type 1 and Type 2 pneumocytes respectively
Type 1 - squamous, Type 2 - cuboidal and clustered
What do clara cells do and what is their morphology?
Nonciliated columnar. Secrete component of surfactant, degrade toxins, act as reserve cells
What ratio in amniotic fluid is used to evaluate fetal lung maturity and what is the cutoff?
Licithin to spingomyelin ratio. If greater than 2 it indicates lung maturity
When does the lung epithelium become cuboidal ciliated?
After the terminal bronchiole
At what vertebral level does each of the three major structures pass through the diaphragm?
IVC - T8, Esophagus - T10, Aorta - T12
Formula for dead space
Vt * (PaCO2 - PeCO2) / (PaCO2)
What is responsible for the higher affinity for O2 of fetal hemoglobin?
A lower affinity for 2,3-BPG
Treatment for cyanide poisoning and what is the reasoning?
Nitrites. Oxidizes hemoglobin to methemoglobin (high affinity for cyanide). This keeps CN- away from cytochrome oxidase. Then give thiosulfate to bind cyanide
What does heme do regarding O2 and H+ in the lungs and tissue respectively?
Lungs - bind O2 and give up H+, Tissue - release O2 and pick up H+
Cause of primary pulmonary hypertension
Inactivation mutation of BMPR2 gene (normally inhibits vascular SM proliferation)
What type of cell mediates intimal fibrosis?
Smooth muscle cells
What is the pO2 in the LA relative to the end of the pulmonary capillaries and why?
Slightly lower in the LA because deoxygenated blood from bronchial veins mixes with oxygenated blood in the pulmonary veins
Formula for O2 content
(1.34 x Saturation) + pO2
Alveolar gas equation
PAO2 = PIO2 - PaCO2/R. Normally: PAO2 = 150 - PaCO2/0.8
Normal A-a gradient
10-15 mmHg
Causes of increased A-a gradient
Shunting, V/Q mismatch, fibrosis
Where in the lung are ventilation, perfussion, compliance, and pO2 respectively the highest?
Ventilation - highest at top lowest at bottom, Perfussion - highest at bottom, lowest at top. Compliance - highest at bottom, lowest at top. pO2 - highest at top, lowest at bottom
Give the relationship of PA, Pa, and Pv for each zone of the lung (Zone 1 is most superior, Zone 3 is most inferior)
Zone 1 - PA > Pa > Pv. Zone 2 - Pa > PA > Pv. Zone 3 - Pa > Pv > PA
What change is seen in renal excretion of bicarb at high altitude and what can you give to augment this?
Increased bicarb excretion, give acetazolamide to augment
What heart abnormality may be seen after living at high altitude for long time?
RVH due to pulmonary vasoconstriction
Imaging test of choice for pulmonary embolus
Helical CT
Virchows triad
Stasis, hypercoagulability, endothelial damage
Homans sign
Dorsiflexion of the foot leading to tender calf muscles, check in suspected DVT
Changes seen in RV, FVC and FEV1/FVC in obstructive lung disease
RV up, FVC down, FEV1/FVC down (characteristic)
Reid index
Measure of gland depth/total thickness of bronchial wall. Above 50 percent in COPD
Which is the blue bloater and which is the pink puffer?
Pink puffer is emphysema, blue bloater is chronic bronchitis
4 main obstructive lung diseases
Emphysema, Chronic Bronchitis, Asthma, Bronchiectasis
Is exercise-induced asthma immune? Is it more or less common than regular asthma?
Less common, it is non-immune
Change in FVC, TLC, and FEV1/FVC in restrictive lung disease
FVC and TLC down, FEV1/FVC normal or up (greater than 80 percent)
Interstitial restrictive lung diseases (9)
ARDS, neonatal RDS, Pneumoconioses, Sarcoid, Idiopathic pulmonary fibrosis, Goodpasture, Wegener, Eosinophilic granuloma (histiocytosis X), Drug toxicity (bleomycin, busulfan, amiodarone)
Which pneumoconiosis is associated with eggshell calcifications of hilar lymph nodes?
Silicosis
Caplans syndrome
RA in pt with coal miners pneumoconiosis
What part of the lung is primarily affected by each of the three major pneumoconioses?
Coal miners - upper lobes, Silicosis - upper lobes, Asbestosis - lower lobes
What cells are messed up by silicosis and what is the implication of this?
Macrophages. May increase susceptibility to Tb
Sites of exposure to silicon and asbestos respectively
Silicon - foundries, sandblasting, mines. Asbestos - shipbuilding, roofing, plumbing
Which pneumoconiosis is associated with ivory white calcified pleural plaques?
Asbestosis
What cancers are increased in asbestosis?
Bronchogenic carcinoma and mesothelioma
Which pneumoconiosis is associated with dumbell shaped rods in in macrophages?
Asbestosis
Fibrocalcific parietal pleural plaques in posterolateral mid-lung zones over the diaphragm
Asbestosis
At what point in gestation is surfactant made most abundantly?
35th week
Risk factors for neonatal RDS
Prematurity, maternal diabetes, cesarean delivery (decreased release of fetal glucocorticoids)
Treatment for neonatal RDS
Maternal steroids before birth, artifical surfactant, thyroxine
Major causes of ARDS (7)
Trauma, sepsis, shock, gastric aspiration, uremia, acute pancreatitis, amniotic fluid embolism
What causes the damage in ARDS?
Neurophils destroy alveolar wall, coagulation cascade is activated, oxygen free radicals go to town
What changes are seen in each of the following parameters during ARDS: capillary permeability, compliance, work of breathing, V/Q matching, and PCWP?
Capillary permeability down, compliance down, WoB up, V/Q matching down, PCWP normal
Why is it that FEV1/FVC may actually be increased in restrictive lung disease
Fibrosis is holding airway open (increased radial traction)
What CBC finding occurs in chronic sleep apnea?
Erythrocytosis (increased epo release secondary to hypoxia)
Which way does the trachea deviate in tension and spontaneous pneumothorax respectively?
Towards lesion in spontaneous and away in tension
What leads to SVC syndrome?
Mediastinal spread of a bronchogenic tumor
Give the location (central or peripheral) of the following lung cancers: small cell, adenocarcinoma, squamous cell, large cell
Small cell - central, adenocarcinoma - peripheral, scc - central, large cell - peripheral
In right heart failure what works to decrease pulmonary edema and what tends to increase it?
Lymphatic drainage can increase to compensate for it, however, aldosterone levels are usually high due to low CO, which makes it worse
Most common causes of lobar, broncho, atypical pneumonia respectively
Lobar - pneumococcus, klebsiella. Broncho - s aureus, h flu, klebsiella, s pneumoniae. Atypical - RSV, adenovirus, mycoplasma, legionella, chlamydia
Lung abscess - risk factors, most common organisms, and characteristic finding
Risk factors - alcoholism, seizure d/o, CVA, dementia. Organisms - S auerus, anerobes (bacteroides, fusobacterium, peptostreptococcus). Find air-fluid levels on CXR
What type of hypersensitivity is hypersensitivity pneumonitis and whom is it most commonly seen in?
Seen in farmers and people exposed to bird. Mixed type 3/4
What usually causes a spontaneous pneumothorax?
Rupture of apical blebs. Seen in tall, thin, young, males
Phases of lobar pneumonia and the time frames of each
Congestion (first 24 hrs), Red hepatization (days 2-3), Grey hepatization (days 4-6), Resolution
What are the typical endings for 1st and second generation H1 blockers respectively?
1st gen is -en/-ine or -en/-ate. Second gen is -adine
List the first generation H1 blockers (3)
Diphenhydramine, dimenhydrinate, chlorpheniramine
What are the main differences between first and second generation H1 blockers?
1st gen used for motion sickness and sleep aid in addition to allergy. Second gen less sedation due to decreased CNS penetration
List the second generation H1 blockers (4)
Loratadine, fexofenadine, desloratadine, cetirizine
Toxicities of 1st generation H1 blockers
Sedation, antimuscarinic, anti alpha adrenergic
Isoproterenol
Non specific B-agonist which relaxes bronchial smooth muscle but also causes tachycardia
Albuterol
B2 agonist, use in acute exacerbation
Salmeterol
Long acting b2 agonist. Use for prophylaxis. AEs are tremor and arrhythmia
Theophylline
Inhibits PDE, leading to bronchodilation. Narrow therapeutic window. Metabolized by P450. Blocks adenosine
Ipratropium
Blocks muscarinic receptors (prevents bronchoconstriction). Use in asthma and COPD
What corticosteroids are useful in asthma and how do they work?
Beclomethasone and prednisone. Inhibit NF-KB which induces TNF-a and other inflammatory agents. 1st line for chronic asthma
Zileuton
Lipoxygenase pathway inhibitor. Use in asthma
Zafirlukast and montelukast
Block leukotriene receptors. Use in asthma (esp aspirin induced)
What should you tell patients that are on chronic corticosteroids to do?
Wash mouth out recently to prevent oral candidiasis
Guaifenesin
Expectorant. Does not suppress cough reflex
N-acetylcysteine
Mucolytic. Use in CF. Antidote for acetaminophen overdose
Bosentan
Used in pulmonary HTN. Antagonizes endothelin-1 receptors.
Dextromethorphan
Antitussive. Antagonizes NMDA glutamate receptors. Synthetic analog of codeine. Mild opioid. Abuse potential
Pseudoephedrine and phenylephrine
Sympathomimetic alpha agonists for nasal decongestion.
Methacholine
Muscarinic receptor agonist. Use in asthma challenge testing
Asthma in patient with chronic pain syndrome
Likely to be NSAID asthma
Type of hypersensitivity in NSAID asthma
TRICK QUESTION. It is not hypersensitivity, it is because block of COX overactivates LOX pathway
Liver cell adenoma in body builder
Assume its anabolic steroids
What direction will the diaphgram move on the side of the lesion in spontaneous and tension pneumothorax respectively?
Spontaneous - up on side of lesion, tension - down on side of lesion
Give the most common cause of 3 types of pneumonia - community typical, community atypical, and nosocomial infections
Community typical - strep pneumo, comunity atypical - mycoplasma pneumo, nosocomial - e coli, pseudomonas, staph aureus. Do not get strep pneumo in hospital
Decreased percussion, increased tactile fremitus, egophony, pectoriloquy
Consolidation (eg lobar pneumonia)
What is the most common cause of bronchiolitis?
RSV
What is the target of the influenza vaccine?
A antigen
Staccato cough
Chlamydia trachomatis in newborn
Most common cause of conjuctivitis in second week of life
Chlamydia trachomatis
Typical source of legionella
Water coolers (is a water loving bug like pseudomonas)
When you have an atypical pneumonia, what finding should make you suspect legionella?
Hyponatremia
Extrapulmonary effects of legionella
Interstitial nephritis (kills JG cells, lowering renin levels which is how you get hyponatremia)
Treatment for legionella
Erythromycin
Fungal infections in indwelling catheters
Candida
Fungus carried by starlings and bats
Histoplasmosis
Narrow based buds
Cryptococcus
Pigeons
Cryptococcus
Where does cryptococcus hide out?
Air conditioners
Treatment for cryptococcus
Amphotericin B
Broad based bud
Blastomyces
Fungus associated with earthquakes
Coccidioides
Most common complication of aspergilloma
Massive hemoptysis
Most common cause of space occupying lesion in the brain of an AIDS patient
Toxoplasmosis
Most common AIDS defining lesion
PCP
Name a systemic fungus, a cancer, and a bacterium that can cavitate like Tb
Histoplasmosis, SCC of the lung, Klebsiella
What do acid fast stain actually stain?
Mycolic acids
Where will a foreign body go if you are sitting or standing up?
Posterobasal segment of right lower lobe
Where will a foreign body go if you are lying down
Superior segment of right lower lobe
Where will a foreign body go if you are lying on your right side
1) Middle lobe or 2) Posterior segment of right upper lobe
Where will a foreign body go if you are lying on your left?
Lingula
What is the most common site for embolization?
Femoral vein (as opposed to thrombosis, where most common site is deep veins of leg)
What do you have increased risk of with coal workers pneumonconiosis?
Tb but not cancer
Treatment and main extrapulmonary symptom in sarcoidosis
Uviitis. Steroids
Cause of silo fillers disease
Fermation of gas leads to nitrogen dioxide, which gets inhaled. Wheezing, dyspnea
Cause of farmers lung
Thermophilic actinomyces (a mold) causes a hypersensitivity reaction and restrictive lung disease
Bysinosis
Textile industry worker with dyspnea, feel better on weekend. Hypersensitivity and restrictive lung disease
Is the lung disease in Goodpasture obstructive or restrictive?
Restrictive
What is the site of disease in chronic bronchitis, asthma, and bronchiolitis?
Terminal bronchioles
Histologic findings in chronic bronchitis
Goblet cell metaplasia, mucus gland hyperplasia, mucous plugs
Type of gas exchange defect in chronic bronchitis
Ventilation perfusion mismatch
What is the gas exchange defect in emphysema?
Even loss of ventilation and perfusion (will not have retention of CO2)
Centrilobular emphysema
Most associated with smoking. Primarily upper lobes. Destruction of respiratory bronchiole.
Panacinar emphysema
Entire respiratory unit destroyed, associated with total lack of a1 antitrypsin. Mostly affects lower lobes
Pathogenesis of bronchiectasis
Infection, destruction of elastic tissue support, dilation of airways. Segmental bronchi, filling with pus
Patient coughing up huge amounts of pus
Likely to be bronchiectasis. Most common cause is CF
Most common primary lung cancer
Adenocarcinoma, followed by squamous and then small cell
