ekadar's version from 2015-10-08 11:15

gas exchange

Question Answer
level for best gas exchange level 2
central chemo receptors respond tochange in PCO2 of blood OR pH of the CSF (NOT pH OF BLOOD!!!)
peripheral chemo receptors respond to change in PaO2
which receptors are suppressed by O2 admin?central receptors, so peripheral receptors take over
where are central receptors?medulla
where are peripheral receptors?carotid and aortic bodies
main stimulus for involuntary control of breathing?arterial PCO2 via central chemo receptors in medulla via pH of CSF
voluntary controlcerebrum
dyspneause of accessory muscles
accessory musclesexternal intercostals, sternoclidomastoid, scalene muscles
pulm hypoplasia in infant?diaphragmatic hernia (bowels in chest)
diaphragm attached to which rib?12th
referred pain from diaphragm?shoulders
cutting through chest wall layersintercostal muscles, parietal pleura, visceral pleura
what does CO2 do to cerebral perfusion?dilates cerebral blood vessels--> increased cerebral blood flow --> causing headaches
absence of CO2 and cerebral perfusion?constricts cerebral blood vessels --> increasing cerebral vascular resistance
give O2 too fast to a COPD patient?respiration rate would increase bc CO2 would actually rise
which turbinate drains lacrimal ducts?inferior turbinate
nasal polyps in adultNSAID allergy (overproduction of lukotrienes)
nasal polyps in kidscystic fibrosis
which turbinate is closest to sphenoid sinus drainage?upper turbinate
thumb sign on CXRH. flu epiglottitis
steeple sign on CXRparainfluenza croup (laryngotracheal bronchitis)
multiple laryngeal polyps?HPV
single laryngeal polypmechanical strain from vocalists
infant with inspiratory stridormost commonly larygomalacia (larynx is too soft)
increased percussionpneumothorax
decreased percussionpleural effusion or consolidation/pneumonia/atelectasis
decreased fremituspneumothorax, pleural effusion
increased fremitusconsolidation/pneumonia
decreased breath soundsall problems (pneumothorax, pleural effusion, consolidation)
aspiration when standing --> which lobe?anterior/inferior R lower lobe
aspiration when supine --> which lobe?posterior segment of R upper lobe
how does bronchiectasis normally present?hemoptysis
where is bronchiectasis seen?tumor obstruction, ABPA, CF, Kartageners
9 triplets and nothing in the center?basal body derived from centrioles
9 doublets and a singlet microtubule in the center?cilia/flagella axoneme
what microtubule protein moves vesicles toward the nucleus/center?Dynein
what microtubule protein moves vesicles away from the center?Kinesin
what does nicotine do to cilia?paralyzes the mucociliary escalator
centriacinar emphysemasmoking!
panacinar emphysemaalpha1 antitrypsin
paraseptal emphysemablullae --> rupture and cause spontaneous pneumothorax in tall thin men

what kind of hypoxemia is this?

Question Answer
opiateshypoventilation of central origin
myasthenia gravishypoventilation of peripheral origin
rib fracturehypoventilation of peripheral origin
morbid obesityhypoventilation of peripheral origin
high altitudehypoventilation of peripheral origin
pulmonary embolismV/Q mismatch decreased perfusion (low Q) (dead space infinity)
pneumoniadecreased diffusion capacity
sarcoidosisdecreased diffusion capacity
asbestosdecreased diffusion capacity
hyaline membrane diseasedecreased diffusion capacity
emphysemadecreased diffusion capacity and V/Q mismatch
asthmaV/Q mismatch
bronchiectasisV/Q mismatch
bronchopneumoniaV/Q mismatch
foreign body aspirationV/Q mismatch (shunt 0)
granulomatous diseasesV/Q mismatch
COPDV/Q mismatch
respiratory zone problemdecreased diffusion capacity
obstructed conducting zoneV/Q mismatch
pulmonary edema mechanismincreased hydrostatic pressure or decreased oncotic pressure
high A-a gradientV/Q mismatch, diffusion limitation, R -->L shunt
normal A-a gradienthigh altitude, hypoventilation
causes for hypoxiaanemia, CO poison, hypoxemia
hypoxia definitiondecreased O2 delivery to tissues
hypoxemia definitiondecreased PaO2
blood gas findings in an acute PEdecreased PCO2, increased pH and low PaO2. No renal compensation in an acute state

obstructive or restrictive?

Question Answer
increased TLCobstructive
increased FRCobstructive
increased RVobstructive
decreased FEV1/FVCobstructive
decreased TLCrestrictive
decreased FRCrestrictive
increased FEV1/FVCrestrictive
breath fast and shallowrestrictive
breath slow and deepobstructive
scoop out line on graphobstructive
increased to normal FEV1restrictive
best parameter to measure severity of longstanding disease?FEV1/FVC
alveoli get largerobstructive
alveoli get smallerrestrictive
chronic bronchitisobstructive
old ageobstructive
langerhans cell histiocytosisrestrictive
what are charcot leyden crystals?degenerated eosinophils seen in asthma
what are curschmann spirals?shed epithelium from mucus plugs in asthma
extrinsic asthmaallergic or atopic type I HSR but eosinophils are impicated, also NSAID allergy
intrinsic asthmanon-allergic. usually adults, triggered by infection, exercise, cold air, no hypersensitivity but mast cells are implicated. Sensitive to histamine
type II pneumocyte hyperplasiarestrictive lung disease
histology of sarcoidosisnoncaseating granulomas, macrophages, CD4+ cells
factors that increase the risk of NRDSprematurity, diabetic moms (insulin from fetal hyperglycemia decreases surfactant), cesarian delivery
work of breathing optimal when in restrictive diseasewhen RR is increased and TV is decreased


Question Answer
SIADHsmall cell
cushingsmall cell (ectopic ACTH)
PTHrpsquamous cell
Lambert-Eatonsmall cell (but any lung cancer)
Horner's syndromepancoast tumor invasion of superior cervical ganglion
erythema/swelling of face, increased JVP when supineSVC syndrome from invasion of central tumors in up role of lung
chylothoraxthoracic duct invasion
lytic bone lesionslung cancer mets to bone
Blastic bone lesionsprostate cancer mets to bone
both lytic and blastic bone lesionsbreast cancer to bone
chronic hemoptysisadenocarcinoma
sudden fatal hemoptysiscentral tumors
small blue cell tumorsmall cell
L-mycsmall cell
keratin pearlssquamous cell
most associated with asbestossquamous cell
increased 5HT and 5-HIAAcarcinoid
cancer lines alveoli wallsbronchioalveolar
subtype of adenocarcinomabronchioalveolar
undifferentiated giant cellslarge cell
kulchitsky cellssmall cell
only chemo therapy for treatmentsmall cell
chromogrannin +small cell, carcinoid
mucin +adenocarcionoma
most common in nonsmokersadenocarcinoma
aerogenous spreadadenocarcinoma
desmosomessquamous cell
beta HCGlarge cell
shoulder painpan coast tumor
hemorrhagic pulmonary embolismmesothelioma
most common overalladenocarcinoma
hypercalcemiasquamous cell


Question Answer
shipyard workersasbestosis
pleural plaqueasbestosis
bronchogenic carcinomaasbestosis synergistic effect with tobacco
psammoma bodiesmesothelioma
associated with TBsilicosis
looks like sarcoidosisberryliosis
ferruginous bodiesasbestosis (stain with iron)
bottom of lungasbestosis
miningsilicosis, coal workers lung
glass productionsilicosis
multiple calcified nodules in upper lung lobessilicosis
increased incidence of lung cancer (bronchogenic carcinoma>mesothelioma)asbestosis

Lung cancer

Question Answer
Only lung cancer types not assoc with smokingbronchioloalveolar
bronchial carcinoid
Where lung cancers metastasize toadrenals, brain, bone, liver
Adenocarcinoma location and characteristicsPeripheral
Most common lung cancer in nonsmokers and females
Activating mutations in k-ras
Assoc w hypertrophic osteoarthropathy (clubbing)
Bronchioalveolar subtype - CXR looks like pneumonia with hazy infiltrates - great prognosis
Adenocarcinoma, bronchioloalviolar subtype histologygrows along alveolar septa → apparent "thickening" of alveolar walls
Squamous cell carcinoma location and characteristicsCentral
Hilar mass
hyperCalcemia (produces PTHrP)
Squamous cell carcinoma histologyKeratin pearls and intercellular bridges
Small cell (oat cell) carcinoma location and characteristicsCentral
Undifferentiated → very aggressive
May produce: ACTH, ADH, or Antibodies against presynaptic calcium channels (Lambert-Eaton syndrome)
Amplification of myc oncogenes
Inoperable - treated with chemo
Small cell (oat cell) carcinoma histologyNeuroendocrine Kulchitsky cell neoplasm → small dark blue cells
Large cell carcinoma location and characteristicsPeripheral
Highly anaplastic undifferentiated tumor
poor prognosis
Removed surgically, less responsive to chemo
Large cell carcinoma histologyPleomorphic giant cells
Bronchial carcinoid tumor characteristicsExcellent prognosis - mets are rare
Sxs are d/t mass effect
Carcinoid syndrome: serotonin secretion → flushing, diarrhea, wheezing
Bronchial carcinoid tumor histologynests of neuroendocrine cells
chromogranin positive
Mesothelioma location and characteristicsPleural
Hemorrhagic pleural effusions and pleural thickening
Mesothelioma histologyPsammoma bodies
Pancoast tumor location and characteristicsApex of lung
May affect cervical sympathetic plexus → Horner's syndrome: ipsi ptosis, miosis, anhidrosis
Superior vena cava syndromeObstruction of SVC → impairs blood drainage from head ("facial plethora"), JVD, upper extremety edema
Caused by malignancy and thrombosis from indwelling catheters
Medical emergency
Can raise ICP → HAs, dizziness, and ↑ risk of aneurysm/rupture of cranial arteries

Pneumonias/Pleural effusions/pneumothorax

Question Answer
Lobar pneumonia organismsStrep pneumoniae (MCC)
Bronchopneumonia organismsStrep pneumoniae
Staph aureus
H. influenzae
Interstitial (atypical) pneumoniaViruses (influenza, RSV, adenoviruses)
Lobar pneumonia characteristicsIntra-alveolar exudate → consolidation
may involve entire lung
Bronchopneumonia characteristicsAcute inflammatory infiltrates from bronchioles into adjacent alveoli
patchy distribution involving 1+ lobes
Interstitial (atypical) pneumonia characteristicsDiffuse patchy inflammation localized to interstital areas at alveolar walls
Distribution invovling 1+ lobes
Generally follows more indolent course
Lung abscessCaused by bronchial obstruction (cancer), aspiration (alcoholics, epileptics, other unconcious-prone diseases)
Air-fluid levels often seen on CXR
Lung abscess organismsStaph aureus
anaerobes: bacteroides, fusobacterium, peptostreptococcus
Hypersensitivity pneumonitisMixed type 3/4 hypersensitivity rxn to environmental antigen
→ dyspnea, cough, chest, tightness, HA
Often seen in farmers and those exposed to birds
transudate (pleural effusion)↓ protein content
Due to increased hydorstatic pressure or decreased oncotic pressure
Exudate (pleural effusion)↑ protein content
occurs in states of increased vascular permeability.
Lymphatic pleural effusionChylothorax
Due to thoracic duct injury from trauma, malignancy, Milky-appearing fluid
↑ triglycerides
Spontaneous pneumothoraxTall, thin, young males because of rupture of apical blebs
trachea deviates toward affected lung
Tension pneumothoraxTrauma or lung infxn
Air enters pleural space but can't exit
trachea deviates away from affected lung
diseases have transudatesHF, nephrotic syndrome, hepatic cirrhosis
diseases have exudatesmalignancy, pneumonia, collagen vascular disease, trauma

Obstructive lung diseases

Question Answer
Chronic bronchitisHypertrophy of mucus-secreting glands in bronchi → Reid index > 50% (thickness of gland layer/total thickness of bronchial wall)
Findings: wheezing, crackles, cyanosis, late-onset dyspnea
EmphysemaEnlargement of air spaces → destruction alveolar walls & ↓ recoil, ↑ compliance
Centrilobular: smoking release of elastases from neutrophils and macrophages
Panacinar: α1-antitrypsin deficiency

Exhalation through pursed lips: prevents collapse by ↑ airway pressure
AsthmaSmooth muscle hypertrophy
Curschmann's spirals - shed epithelium forms mucus plugs
Charcot-Leyden crystals - formed from breakdown of eosinophils in sputum
BronchiectasisChronic necrotizing infxn of bronchi
→ permanently dilated airways, purulent sputum, recurrent infxns, hemoptysis
Bronchiectasis is assoc wbronchial obstruction,smoking, Kartagener's syndrome, CF, allergic bronchopulmonary aspergillosis
PFTs Obstructive lung diseasesAirways close prematurely at high lung volumes
↑ RV and ↓ FVC
↓↓ FEV1, ↓ FVC → ↓ FEV1/FVC ratio
V/Q mismatch

Restrictive lung disease

Question Answer
neonatal respiratory distress syndrome risk factorsPrematurity, maternal diabetes, cesarean deliver (↓ release of fetal glucocorticoids)
lecithin:sphingomyelin ratio < 1.5
Neonatal respiratory distress syndromeSurfactact deficiency → ↑ surface tension → alveolar collapse
tx w maternal steroids before birth, artificial surfactant for infant
ARDS causestrauma, sepsis, shock, gastric aspiration, uremia, acute pancreatitis, amniotic fluid embolism
ARDS pathogenesisNeutrophilic substance toxic to alveolar wall → ↑ alveolar capillary permeability → protein-rich leakage into alveoli → intra-alveolar hyalinemembrane
PFTs for restrictive lung disease↓ lung volumes (↓ FVC and TLC)
FEV1/FVC > 80%
therapeutic supplemental O2 in NRDS can result in RIB(Retinopathy of prematurity, Intraventricular hemorrhage, Bronchopulmonary dysplasia)