Flashcards in Respiratory Deck (208):
What intracellular signal is affected by beta adrenergic agonists?
Smooth muscle relaxes (from B2 stim) from increased cAMP
Cause of hypoxemia with a normal A-a difference?
high altitude (less O2 in the air)
trachea deviates toward normal lung
Trachea deviates away from normal lung
atelectasis (collapsed lung)
kerley B lines tell you
edema of interlobular septa
flattened diaphragm on Xray
Acute rejection of lung affects
pulmonary and bronchial circulation
Chronic rejection of lungs affects
In healthy individuals, respiration is perfusion rather than diffusion limited (exercise, pulmonary embolism, etc).
Which is more affected in diffusion limitation, CO2 or O2 levels?
O2 levels. CO2 levels have a much higher diffusion capacity across the respiratory membrane. If you see VERY low pCO2 at the alveoli, this indicates a perfusion not a diffusion limitation
How do you measure fetal lung maturity?
Lecithin/Sphingomyelin ratio. They are equal until 3rd trimester, when Type II pneumocytes start secreting surfactant
Eggshell calcifications of hilar nodes and birefringent silica particles surrounded by fibrous tissue
fusiform rods seen with iron protein (prussian blue stain)
pulmonary asbestos. Will see an interstitial pattern on Xray
Chloride shift in RBCs caused by
--CO2 carried in bicarb form predominantly
--when bicarb leaves the RBC to dissolve in plasma, chloride enters the cell to maintain charge neutrality
how does hemoglobin carry CO2
15% as carbamate Hb-NH-CO2
85% as HCO3 (carbonic anhydrase
Which cancer causes SVC syndrome
small cell lung cancer. Causes headache, facial/upper extremity edema, and dilated veins
--hoarseness: recurrent laryngeal
--dysphagea: esoph. compression
Sx of phrenic nerve irritation
1. hiccups, SOB, elevation of hemidiaphragm on X ray
bronchioles and terminal bronchioles
--Large bronchi are part of the large airways
What cells do you find in bronchi
What do you find in the terminal bronchioles
pseudostratified ciliated columnar cells
--smooth muscles of airway walls(disappear after terminal bronchioles
type of cell in respiratory bronchioles
cuboidal cells without cilia
What secretes elastase
neutrophils and macrophages
Where is there mixing of blood normally?
bronchial veins mix in
2*T/R. This is the PRESSURE YOU NEED INSIDE THE BALLOON TO KEEP IT OPEN
what indicates fetal lung maturity?
lecithin: sphingomyelin ratio of 2
when are mature levels of pulmonary surfactant achieved?
Week 35. synthesis starts at week 26
When do alveoli tend to collapse
when radius is small (with expiration)
Which is the MOST important component of surfactant
type II cells
cuboidal clustered cells that secrete pulmonary surfactant
columnar cells that secrete component of surfactant and degrade toxins
Relation of pulmonary artery to bronchus
-Right PA anterior to bronchus
-Light PA superior to bronchus
Which lung are you more likely to inhale a foreign body into?
What enters the diaphragm at T12?
Where should you do a thoracentesis?
MCL: 5-7th rib
Mid axillay: 7-9th rib
paravertebral: 9th-11th rib
Muscles of inspiration during exercise
amount of air that can still be breathed in after normal inspiration
how much more can you breathe in after a normal breath
how much more can you breathe out after a normal breath
Dead space calcuation
Vt x (Paco2-Peco2)/Paco2
Which part of the lungs is the biggest contributor to functional dead space?
apex of lungs
Taut vs relaxed forms of hemoglobin (2alpha + 2beta)
Taut: low affinity for O2
Relaxed: high affinity for O2
What factors cause taut form to dominate?
increased chloride, 2,3 BPG, H+, and CO2
how do you treat methemoglobinemia?
How do nitrites cause poisoning?
Convert Fe2+ to Fe3+
fetal hemoglobin has a lower affinity for
How do you treat cyanide poisoning?
Nitrites--make methemoglobin which can bind cyanide.
Also give thiosulfate to bind cyanideq
how does CO shift the oxygen hemoblogin curve?
LEFT shift. Decreased maximum bound and loss of sigmoidal shape
Increased affinity for O2, less unloading
When hemoglobin curve shifts to the right
decreased affinity for O2 (more unloading, at tissue level)
Causes of right shift
Pulmonary vascular resistance is lowest at
--increased lung volume: compresses alveolar vessels, but less resistance in extra-alveolar vessels
are you perfusion or diffusion limited during exercise?
perfusion limited. Still able to reach normal PA at the end of the capillary
When might you be diffusion limited?
Emphysema (decreased surface area)
Fibrosis (increased thickness)
Normal pulmonary artery pressure
Cause of primary pulmonary HTN
Cause of secondary pulmonary HTN
autoimmune dz like systemic sclerosis
How do you calculated pulmonary vascular resistance?
Vgas=A/T x Dk(P1-P2)
When do you see an increased Aa gradient
cause of hypoxemia with a normal Aa gradient
V/Q ratio at apex of lung
3 (wasted ventilation)
V/Q ratio at the base of lung
0.6 (wasted perfusion)
are ventilation/perfusion greater at the lung base or apex?
both are greater at the base than the apex
VQ ratio during exercise
1-->apical arteries expand
SHUNT. Lots of blood flow, no ventilation. Airway obstruction!
DEAD SPACE. Lots of airflow, no blood. pulmonary embolism
Who would benefit from high flow 100% O2?
Person with Deadspace. We assume there are some areas of the lung that are still getting blood.
Shunt does NOT improve with 100% oxygen because the air is not even reaching the blood!
Most of CO2 is transported in what form?
bicarbonate in the plasma
oxygenation of Hb promotes dissociation of H+ from Hb within the RBC
--H+ binds HCO3 and forms free CO2 with carbonic anhydrase
How else is CO2 transported?
-carbaminohemoglobin (CO2 bound to the N terminus of hemoglobin)
H+ in peripheral tissues causes shift to the right=unloading O2
Changes at high altitude
Decreased PO2 and PCO2
Increased renal excretion of bicarbonate (increase this with acetazolamide)
-->Watch out for cor pulmonale
Changes in the lungs with exercise
V/Q ratio -->1
No change in PaO2 and PaCO2!!
Increase in venous CO2 content and decrease in venous O2 content
dorsiflexion of foot causes calf pain
Homan's sign, think DVT
Treatment for acute DVT
Treatment for long-term prevention of DVT
Think pulmonary emboli!
What is bronchiolitis obliterans pneumonia?
Formation of granulation tissue with pneumonia. Causes obstruction of airways
How od you treat bronchiolitis obliterans pneumonia?
How do you tell whether a patient died because of a pulmonary embolism or if the thromboembolism formed after death?
Lines of Zahn
Tells you thickness of glandular layer compared to bronchial wall
--Over 50% in patients with bronchitis
Cause of chronic bronchitis
Hypertrophy of mucus secreting glands
Cause of emphysema
enlargement of airspaces and decreased recoil with destroyed alveolar walls
breathing through pursed lips
emphysema. Increased airway presure and prevent airway collapse resulting from increased compliance
centriacinar emphysema, upper lobes
panacinar emphysema, lower lobes
Cause of asthma
Histology of asthma
smooth muscle hypertrophy
Curschmann's spirals (mucus plugs)
Charcot-leyden crystals (breakdown of eosinophils)
pulsus paradoxus seen in
obstructive sleep apnea
necrotizing infection of bronchi causing dilated airways, purulent sputum, infections, and hemoptysis
bronchiectasis associated with
smoking (ciliary motility)
Cause of restrictive lung disease with an abnormal A-a gradient
Interstitial lung diseases
-idiopathic pulmonary fibrosis
which drugs can cause interstitial lung disease?
coal miner's lung
sandblasting, mines, foundries
pathogenesis of silicosis
macrophages release fibrinogenic factors in response to silica
pts with silicosis are susceptible to
TB and bronchogenic carcinoma
eggshell calcifications of hilar lymph nodes
shipbuilding, roofing, plumbing
affects upper lobes
affects lower lobes
golden brown fusiform dumbbells
Ivory white calcified pleural plaques
asbestos exposure! But they do not indicate precancerous lesion
Asbestos associated with
mesothelioma and bronchogenic carcinoma
neonatal respiratory distress syndrome caused by:
Lecithin: sphingomyelin ratio will be less than 1.5
What is your other concern with neonatal respiratory distress syndrome?
Low O2 tension could lead to a PDA
You decide to administer supplemental O2 to a neonate with respiratory distress. What are some complications?
retinopathy of prematurity
Treatment for neonatal respiratory distress syndrome
maternal steroids before birth
artificial surfactant for baby
Risk factors for neonatal respiratory distress syndrome
cesarean delivery (less CRH)
Causes of ARDS
sepsis, shock, trauma,
amniotic fluid embolism
Pathophysiology of ARDS
diffuse alveolar damage
-protein rich leakage into alveoli
-intra-alveolar hyaline membrane
what causes the initial damage precipitating ARDS?
oxygen derived free radicals
What hormone might be elevated in sleep apnea?
decreased breath sounds, dullness to percussion and decreased fremitus
decreased breath sounds, dullness to percussion, decreased fremitus and tracheal deviation towards lesion
decreased breath sounds, hyperresonance, and decreased fremitus with tracheal deviation toward lesion
decreased breath sounds, hyperresonance, and decreased fremitus and deviation away from lesion
bronchial breath sounds with crackles, dullness to percussion, and increased fremitus
consolidation (lobar pneumonia or pulmonary edema)
alpha1 antitryptase is synthesize in
Which TB drug does not affect hepatic fxn
histology: chronic lung rejection
histology: acute lung rejection
perivascular mononuclear infiltrate
Common complications of lung cancer
-superior vena cava
-recurrent laryngeal compression
cough, hemoptysis, bronchial obstruction, coin lesion on x ray or nodule
most common cause of lung cancer
Where do lung cancer metastasize from?
Where to lung cancers metastasize to?
Which lung cancers are NOT associated with smoking?
small cell carcinoma
Most common cause of lung cancer in nonsmokers and women
which cancer is associated with clubbing?
What subtype of adenocarcinoma shows hazy infiltrates and shows thickening of alveolar walls?
prognosis of bronchioloalveolar subtype adenocarcinoma
Which cancers are found centrally?
squamous and small cell
Which cancers are found peripherally?
adenocarcinoma and large cell carcinoma
hilar mass with keratin pearls located centrally
features of squamous cell carcinoma
Histology of small cell carcinoma
undifferentiated with small dark blue cells
paraneoplastic syndrome of small cell carcinoma
the small cell carcinoma cells are derived from
neuroendocrine cells of kulchisky
which kind of cancer can you NOT operate on?
small cell carcinoma
histology of large cell carcinoma
pleomorphic giant cells that are highly anaplastic
how do you treat large cell carcinoma?
remove surgically! chemotherapy is less effective
lung tumor that shows nests of neuroendocrine cells that are chromogranin positive
bronchial carcinoid tumor
Sx of bronchial carcinoid tumor
mass effect, sometimes carcinoid syndrome with serotonin secretion=flushing, diarrhea, wheezing
carcinoma in the apex of the lung that can affect cervical sympathetics and cause horner's syndrome
psamomma bodies in lung cancer located in the pleura with pleural effusions and pleural thickening
Which cancers show psamomma bodies?
papillary thyroid cancer
serous cystadenoma of the ovary
Causes of bronchopneumonia
Causes of Lobar pneumonia
What is hypersensitivity pneumonitis
mixed type III/IV hypersensitivity rxn to environmental antigens
who is predisposed to hypersensitivity pneumonitis?
farmers and birds
inflammation from bronchioles to adjacent alveoli
--patchy distribution involving more than 1 lobe
Cause of a spontaneous pneumothorax
--tall, thin, males
Cause of tension pneumothorax
trauma or lung infection
Name the first generation H1 blockers
Name the second generation H2 blockers
What are the additional benefits of H2 blockers?
Far less sedating than first generation blockers because less entry into the CNS--> good for old people!
What else can you use H1 blockers for?
long acting B2 agonist
side effect of salmeterol, formoterol
tremor and arrhythmia
theophylline blocks action of
which drug is metabolized by p450?
competitively blocks muscarainic receptors, preventing bronchoconstriction
inhibits synthesis of all cytokines.
--inhibits TNF-a production
What is the first line therapy for chronic asthma?
corticosteroids beclomethasone and fluticasone
monoclonal IgE antibody
inications for omalizumab
allergic asthma resistant to inhaled steroids and b2 agonists
good for aspirin induced asthma
mechanism of montelukast zafirlukast
Block leukotriene receptors
5-lipoxygenase pathway inhibitor
B2 agonist mechanism
increases cAMP causing bronchodilation
effect of Ach and adenosine on bronchi
Both cause bronchoconstriction
loosens mucous plugs in CF
Used for pulmonary arterial hypertension:
Antagonizes endothelin 1 receptors to decrease PVR
Decreases cough reflex by antagonizing NMDA glutatmate receptor. Has mild opioid effect when used in excess (give naloxone)
side effects of pseudoephedrine/phenylephrine
Nasal polyps caused by
repeated bouts of rhinitis
Aspirin intolerant asthma
Child with nasal polyps
Angiofibromas occur in
in adolexcent males. continued nose bleeds
naspharyngeal carcinoma associated with
EBV--Naspharyngeal carcinoma and AA.
pleomorphic keratin-positive epithelial cells in a background of lymphocytes
fever, drooling, muffled voice, and inspiratory stridor in a kid
epiglottitis caused by Hflu
cause of bilateral vocal cord nodule
excessive use (singers)
--presents with hoarseness, resolves with rest.
--composed of myxoid CT
laryngeal papilloma caused by
HPV 6 and 11
alcohol and tobacco. presents with hoarseness, cough, stridor
thick mucoid capsule bug
klebsiella. usually aspiration pneumonia
Four phases of lobar pneumonia
grey hepatization (RBCs broken down)
causes of bronchopneumonia
most common cause of secondary pneumonia
pneumonia in COPD
Haemophilus or moraxella
complication of mycoplasma pneumonia
autoimmune hemolytic anemia
pneumonia in farmers and veterinarians with high fever
--no skin rash
where can TB spread to?
2. cervical lymph
3. kidney=sterile pyuria
4. lumbar vertebrae=potts
ABG of someone with pulmonary embolism
respiratory alkalosis (blowing off all your CO2)