Pulmonary Flashcards
errors at embryonic stage of lung development
tracheoesophageal fistula
respiration is possible at how many weeks
25
5 phases of lung development
- embryonic
- pseudoglandular
- canalicular
- saccular
5 alveolar
pulmonary hypoplasia is associated with….
congenital diaphragmatic hernia and Potter sequence
bronchogenic cysts caused by….
abnormal budding of foregut and dilation of terminal or large bronchiole
club cells
located in small airways, secrete component of surfactant, degrade toxins
surfactant synthesis begins at…
week 26, matures at week 35
neonatal respiratory distress syndrome
- surfactant deficiency leading to collapse
- risks: maternal diabetes, C-section (less stress)
- problems: NEC PDA
- treat with steroids
treatment with neonatal O2 can cause
- retinopathy of prematurity
- BPD
- intraventricular hemorrhage
L/S ratio
greater than 2 is healthy, low is predictive for NRDS
airway smooth muscle extends to….
terminal bronchioles
cartilage and goblet cells extend to….
end of bronchi
cilia extend to…..
respiratory bronchioles
number of lobes on each side
left has less lobes (2) and lingula
RALS
right anterior, left superior, relationship of pulmonary artery to bronchus
more likely to aspirate in what side…
right, more vertical
spinal level of things entering the abdomen
T8 - IVC
T10 - esophagus, vagus
T12 - aorta, thoracic duct, azygos vein
I 8, 10 eggs at 12
inspiratory reserve volume
volume you can still breath in after tidal
expiratory reserve volume
volume you can still breath out after tidal
functional residual capaticy
volume left after normal respiration
inspiratory capacity
what can be breathed in after normal exhale
calculation for physiologic dead space
Taco, paco, peco paco
Vd = Vt * (PaCO2 - PeCO2/PaCO2)
lung is most balanced at…
FRC, PVR is at a minimum here
elastic recoil
tendency for a lung to collapse inward
compliance
change in lung volume for a change in pressure, inversely proportional to wall stiffness
surfactant increases compliance
hysteresis
lung inflation curve follows different curve than deflation due to need to overcome surface tension
things that shift hemoglobin curve
shift curve right = more offloading
- CO2, acid, 2,3BPG, temperature
oxygen affinity to hemoglobin
deoxygenated = less affinity
more oxygenation = more affinity
treatment for methemoglobinemia
vitamin C or methylene blue
methemoglobin
iron is in Fe3+ leading to decrease oxygen affinity
- cyanosis and chocolate color blood
causes of methemoglobin
nitrites and benzocaine
carbon monoxide
binds reversibly to hemoglobin at much higher affinity
why does fetal Hb have higher affinity for O2
due to low affinity for 2,3 BPG
3 components of oxygen content of blood
hemoglobin level, hemoglobin saturation, dissolved oxygen
low oxygen in lungs causes vaso….
constriction, shunt blood to better perfused areas
lungs are normally (perfusion/diffusion) limited
perfusion limited - can only be increased with additional blood flow
states of diffusion limited problems
emphysema, fibrosis, CO poisoning - oxygen does not have time to get to hemoglobin
DLCO
measure of diffusion using CO
alveolar gas equation
PAO2 = PIO2 - (PaCO2/0.8)
increased A-a gradient occurs in….
shunting, V/Q mismatches, fibrosis (impaired diffusion)
hypoxia causes
low cardiac output, hypoxemia, anemia, CO poisoning
hypoxemia causes (normal A-a)
hypoventilation, high altitude
hypoxemia causes (high A-a)
V/Q mismatch, diffusion limitation, shunt
V/Q based on area of lung
highest at top, lowest at bottom
V/Q = 0
airway obstruction
V/Q is very large
blood blockage, shunt, if not at 100%, oxygen can help
three forms of CO2 in blood
- bicarb
- bound to Hb at N terminus of globin
- dissolved
Haldane effect
oxygenation of Hb promotes dissociation of H+ leading to CO2 formation
Bohr effect
In tissues with more H+, curve is shifted left leading to oxygen offloading
d-dimer
used to rule out DVT
lines of Zahn
areas of pink - platelets and fibrin vs RBCs found in thrombi before death - distinguish between pre and postmortem thrombi
fat emboli association
bone fractures, liposuction
caplan syndrome
rheumatoid arthritis and pneumoconiosis with intrapulmonary nodules
asbestosis
- higher risk of carcinoma
- prussian blue stain
- risk of pleural effusions
- dumbell rods
berylliosis
- noncaseating granulomas
- effects upper lobes
- aerospace and manufacturing
coal workers
- coal
- black lung
- anthraosis (asymptomatic condition)
silicosis
- fibrosis
- disrupt phagolysosomes and impair macrophages
- eggshell calcifications
mesothelioma
- psammoma bodies
- cytokeratin and calretinin are usually positive
- no smoking
ARDS
- diagnosis of exclusion (must be acute)
- sepsis, pancreatitis, pneumonia, aspiration, trauma, shock
- endothelial damage, permeability, leakage into alveoli
- hyaline membranes
- neutrophilic substances toxic
etiologies of pulmonary hypertension
- primary
- left heart failure
- lung disease
- chronic microemboli
- multifactorial
tracheal deviation in pleural effusion vs ateletctasis vs tension pneumothorax
effusion - away from side of lesion
atelectasis - toward side of lesion
pneumothorax - away (air pushes it)
cryptogenic organizing pneumonia
- noninfectious
- inflammation of bronchioles
- caused by chronic inflammation or drugs (amiodarone)
treatment of lung abscess
clindamycin
pancoast tumor
carcinoma in apex of lung that causes symptoms by invading cervical chain
SVC syndrome
- impaired blood drainage from head
- JVD, upper extremity edema
- malignancy and thrombosis
- risk of aneurysm rupture
SPHERE complications of lung cancer
S - SVC syndrome P - pancoast tumor H - horners syndrome E - endocrine - paraneoplastic R - recurrent nerve compression E - effusions
small cell cancer
- ACTH, SIADH, Lamber-Eaton
- myc oncogenes
- neuroendocrine cells
- chromogranin A, enolase positive
lung adenocarcinoma
- peripheral
- hazy infiltrates
squamous cell
- central, smoking
- hypercalcemia
- keratin pearl and intercellular bridges
