Pulmonary Pearls

ahmadsadaka's version from 2015-06-10 04:48


Question Answer
Talc isHydrated Magnesium silicate
Asbestos isFibrous Hydrated Magnesium silicate
Talc's frequent co-location in underground deposits with Asbestos ore often leads to contamination of powdered talc products with asbestos fibers (T/F)True
Asbestos Fiber typesSerpentines (curved Chrysotiles, 95% of commercially used asbestos) & Amphiboles (shorter straight rods)
Radiological UIP pattern D.DxIPF, Chronic HP, CTDs, Asbestosis, Drugs (Bleomycon, Methotrexate, vincristine ...), Hermansky Pudlak syndrome
Pathogenecity of asbestos fibers depend onCumulative dose exposure, Biodurability, Aspect ratio > 8:1, Surface activity, solubility, Host factors (genetic, lung disease)
Asbestos fibers with more carcinogenecityAmphiboles, > 10 um
Asbestos fibers with more fibrinogenecitySerpentines, >20 um
2 forms of Asbestos in the lungCoated or Uncoated
Asbestos BodyHistological Hallmark of Asbestos exposure - a coated Asbestos fiber - an Asbestos Ferruginous body coated by protein & iron compounds
Silicotic NoduleHistological Hallmark of Silicosis
Asbestosis RxSupportive
Pleural Plaques D.DxAsbestos exposure (also silica, talc, tin), old TB, old Empyema, old Hemothorax, repeated Pneumothorax & pleural Neoplasms (mesothelioma, lymphoma,malignant melanoma, metastasis)
Diffuse pleural thickening =Pachypleuritis
Round atelectasis =folded lung syndrome, Blesovsky's syndrome, shrinking pleuritis with atelectasis, atelectatic pseudotumor & pleuroma
Roud atelectasis D.DxAsbestos exposure, CHF, Dressler's syndrome, Pulmonary infarction, parapneumonic effusion & chest trauma
Risk of lung cancer in smoker & asbestos exposed compared to control50-60 X
Risk of lung cancer in smoker & asbestos exposed compared to smoker only10X
Risk of lung cancer in smoker & asbestos exposed compared to asbestos only5 X


Question Answer
Mesothelioma etiology80% asbestos exposure
PneumoconiosisOccupational ILD caused by inhalation of dust & other particulate matter (usually inorganic) --> inflammation & fibrosis
CWP pathologyCoal macule, nodule, Focal emphysema, PMF
Coal Mine Dust Lung diseaseCWP, Silicosis, Mixed Dust Pneumoconiosis, Chronic Bronchitis, Focal Emphysema, Dust related Diffuse Fibrosis
PMF> 1 cm irregular bilateral UL +/- Cavitation
Caplan's Nodule>1-2 cm Regular rounded Nodule +/- Cavitation, Calcification, Collapse + RA
AnthraciteHQ older Coal, more silica
PeetLQ newer Coal, less silica
commonest type of crystalline silicaQuartz (then cristobalite & tridymite)
combined silica & coal dust exposure -->less silicosis (less surface reactivity & surface free radicals) ==> "Interactive Dust Phenomenon"
Silicosis Radio-Pathologic variationssimple, complicated (PMF), acute (silico-proteinosis)
Silica associated lung diseaseSilicosis, Chronic Bronchitis, emphysema, Silico-tuberculosis, Lung Cancer
Silicosis clinical typesChronic (classical), Accelerated, Acute (silico-proteinosis)
Chronic Silicosis radio.UL nodules
Acute silicosis radioLL alveolar filling
Silico-tuberculosis >PMF, Accelerated, Acute Silicosis
Silicosis Rxwhole lung lavage, BD, O2, anti-TB accordingly
altitude of 5 KMhalves PiO2
Ascent of 18000 feethalves atmospheric pressure
Commercial airliners fly at38000 feet (11.6 KM)
Cabin altitude is at8000 feet (2.4 KM) ==> FiO2 15%, PaO2 60-75 mmHg, SaO2 89-94%
Pre-flight assessmentHistory, 50 m walk test, Hypoxia Challenge test, Hypoxia predictive equations
Who to do HCTanyone with SaO2 <95% , other risky patient
HCT needs O2 ifPaO2 <50mmHg, SaO2 <85%
at Mount Everest, O2 reaches15% of sea-level value ==> PaO2 28, SaO2 70%, PaCO2 7.5
altitude 4500 mbelow which acclimatization --> N. resting HR & COP
High altitude IllnessHypo-Baric Hypoxia
High altitude IllnessesAcute Mountain Sickness, High altitude Pulmonary Edema, High altitude Cerebral Edema
Acute Mountain sicknessAcute (6-10 hrs) HEADACHE, Dizziness, Lassitude, fatigue, GI problems (ANV) in unacclimatized above 2.5 KM
High altitude Cerebral EdemaA.M.S / High altitude Pulmonary Edema + Ataxia &/or AMS
Rx of A.M.SRest & stop ascent, O2, Descent, Acetazolamide / Dexamethasone, Portable Hyperbaric Chamber
Rx of High Altitude Pulmonary EdemaO2, Descent, Nifedipine, b- blocker, CPAP
Hypersensitivity Pneumonitis BALlow CD4/CD8 ratio <1 (with fibrosis ==> reversal dt. inc. Th1)
Hypersensitivity Pneumonitis Histologycellular bronchiolitis, monocytic / lymphocytic interstial infiltrate, small scattered poorly formed granulomata
fro each 11 m (33 feet) below sea level1 atm. increase
Critical level for Hypoxia of Ascent3.3 meters (PaO2 < 30 mmHg ==> LOC)
Inert gas Narcosis at a depth of (compressed air dive)30 meters
Decompression IllnessDCS & Arterial Gas Embolism