Type II pneumocytes surfactant (lecithin)
Proliferate after injury
Type I progenitors
Neonatal Respiratory Distress Syndrome
Polio live v killed vaccine Killed = Salk = IgG
Live = Sabin = IgG + IgA
- can be shed in feces
Neonatal Respiratory Distress: Maternal DM (high insulin)
Etiology + Tx or C-section (low cortisol)
TX: dexamethasone before birth
Lung maturity determined with Amniocentesis of Phospholipids (*type II pneumocytes)
L >> S
Type I pneumocytes Squamous gas diffusion
Elastase in lungs macrophage: lysosomes
PMN: azuronphilic granules
Elastin stretches and recoils due to Lysine interchain crosslinks
air pressure and Air pressure = 0
intrapleural pressure at FRC Intrapleural pressure = -5
Pulm Vasc Resistance is lowest during Exhale of Tidal Volume
Lung Compliance is decreased by LHF, pulmonary edema,
pulmonary fibrosis
Lung Compliance is increased by emphysema, age
Obesity affects ERV and FRC DECREASE
ERV & FRC
Blood flow/min (pulmonary v systemic) pulmonary = systemic
Anatomic pulmonary shunting Bronchial circulation causes
decreased PO2 in LA/LV
than in pulmonary capillaries
More ventilation is at the BASE
, NBME CBSE LATEST UPDATED EXAM 2026- 2027 ALL QUESTIONS WITH CORRECT ANSWERS
O2-Hgb dissociation LEFT shift basic, cold, low 2,3 BPG
low pO2 (compensatory erythrocytosis)
O2-Hgb dissociation RIGHT shift low pH, high 2,3BPG, high T
HOT, ACIDIC
CO2 transport to lungs carbonic anhydrase
Cl shift
Haldane: CO2 released to lung
(Bohr: O2 release to tissue)
CO poisoning causes carboxyhemoglobin
no affect on PaO2
Cyanide poisoning causes lactic acidosis
How to treat cyanide poisoning Amyl nitrite --> Methemoglobin
THEN Thiosulfate (hydroxycobalamin)
Normal A-a gradient 5-15
Hypoventilation: Heroin OD or high altitude
Increased A-a gradient Diffusion impairment (fibrosis)
R-L shunt (aspiration, ARDS)
V/Q mismatch (pulmonary edema
AT --> AT II ACE
where and how (- high in sarcoidosis)
In small pulmonary bV
C5a induces what PMN influx (ie: in lungs)
Korotkoff sound BP cuff - appear and disappear
in inflation/deflation
Pulsus Paradoxus 10mmHg difference in
Korotkoff sound
Pulsus Paradoxus occurs in Cardiac Tamponade
Kussmaul sign JVP rises during inspiration
Constrictive Pericardiditis
Restrictive/Interstitial Lung Disease: Airway widening due to radial traction from fibrosis
A-a, FVC, FEV1, EFR increase Aa
decreased FVC & FEV1
Increased EFR
, NBME CBSE LATEST UPDATED EXAM 2026- 2027 ALL QUESTIONS WITH CORRECT ANSWERS
Sarcoidosis Th1 noncaseating granulmona
bilateral hilar adenopathy
increased ACE
increased IL2, IFNg
1-a-hydroxylase in macrophages: vit D --> HyperCa
Hyper Ca causes stones, thrones, groans, psych overtones
1-a-hydroxylase in macrophages PTH independent conversion of
Calcifediol to calcitriol (bioactive Vit D)
Vit D --> Hyper Ca
Idiopathic pulmonary fibrosis Honeycomb pattern
loss of Type 1 pneumocytes
hyperplasia Type II pneumocytes
Goodpasture HS II
Auto-Ab against BM destroys lung alveoli (restrictive) and renal glomeruli
Obstructive Lung Disease DECREASED FEV1, Decreased FVC
increased RV, FRC, TLC
**different shape
COPD PMN, mo, CD8
V/Q mismatch: O2 induced hypercapnia;
physio dead space
Myeloperoxidase causes Green sputum/pus
Do not give O2 supplement to COPD patient
Decreased stimulation of
carotid bodies = decreased RR
TX COPD with Fluticasone (glucocorticoid)
inhibit cellular reaction
a1-antitrypsin deficiency Serine protease inhibitor
LIVER
LUNG: inc PMN elastase --> emphysema
Asthma dx Methacholine (maCh) challenge
= induce bronchoconstriction
to reduce FEV1
+ test = Airways ARE reactive
B2 agonist MOA B2 (Gs) --> AC --> increase cAMP
Corticosteroid MOA inhibit cytokine synthesis
suppress T lymphocyte
, NBME CBSE LATEST UPDATED EXAM 2026- 2027 ALL QUESTIONS WITH CORRECT ANSWERS
mACh Antagonist ("tropium") MOA inhibit Vagal via ACh
--> decreased Ca
OSA causes pulmonary HTN and RHF
increases EPO which worsens HTN
EPO can do what worsen HTN
on Cardiovascular
Pulmonary Arterial HTN BMPR2
High endothelin, Low NO
SMC hypertophy, fibrosis, narrow lumen
P2 louder than A2
When is P2 louder than A2 Pulmonary Artherial Hypertension
TX pulmonary arterial hypertension Endothelin-R antagonist:
- Bosentan, Ambisentan
PGEi (inc cGMP):
- Sildenafil
Pulmonary Embolism perfusion defect (V/Q mismatch)
sudden SOB + calf swelling
Hypoxemia --> Hyperventilate
--> Respiratory Alkalosis
--> Metabolic compensation in 2 days
dx pulmonary embolism D-dimer test
CT angiogram
Lines of Zahn
Homan's sign (DVT calf pain on dorsiflex)
TX pulmonary embolism Heparin/LMWH
THEN
Warfarin
Fat embolism syndrome Long bone/pelvic fracture
--> neuro, hypoxemia, rash
Fat microglobules in pulmonary arterioles
Spontaenous pneumothorax nontraumatic rupture of subpleural blebs
**20 yo thin TALL man who smokes
DECREASED PRELOAD
Tension pneumothorax Treachea deviates
REQUIRES INTUBATION
ARDS bilateral infiltrate
**PANCREATITIS RISK
1. EXUDATIVE (capillary permeability)
2. Proliferative (collagen)
3. Fibrotic (pulmonary fiborsis + HTN)
What are the risks from ARDS Sepsis
Pancreatitis
Pneumo