High Yield Topics-Respiratory Flashcards
the difference between the partial pressure of oxygen in the alveoli (A) and the arterial (a) partial pressure of oxygen
A-a gradient
Formula for A-a gradient
A-a gradient = PAO2 - PaO2
NORMAL A-a gradient is estimated as
(age/4) + 4
Ex. age 40 should have Aa gradient of <14
Formula for alveolar gas equation (used for measuring PAO2)
PAO2 = PIO2 - (PaCO2/R)
PAO2 = 150 mmHg - (PaCO2/0.8)
A-a gradient (increases/remains normal/decreases) in hypoventilation due to CNS and neuromuscular disorders (no diffusion defect) and in high altitude (despite a lower fraction of inhaled O2)
Remains NORMAL
A-a gradient (increases/remains normal/decreases) in hypoxemia due to shunting, V/Q mismatch, or impaired gas diffusion across the alveoli due to fibrosis or edema
Increases
A-a gradient (increases/remains normal/decreases) with age
Increases
A type of V/Q mismatch due to “airway” obstruction; blood flow without aeration
Shunt
Examples of shunt
- Pneumothorax (alveoli collapse so O2 cannot be filled)
- Atelectasis (alveoli collapse so O2 cannot be filled)
- Pulmonary Edema (filled with gunk so O2 cannot pass through)
- Pneumonia (filled with gunk so O2 cannot pass through)
A type of V/Q mismatch due to “blood flow” obstruction; Aeration without blood flow
Dead Space
Examples causing dead space
- PE or Air Embolism
- Cardiogenic Shock (can’t pump blood to the lungs)
- Hypoxic Pulmonary Vasoconstriction (dec. blood flow)
V/Q ratio for Shunt
0
V/Q = 0/# = 0
V/Q ratio for Dead Space
∞
V/Q = #/0 = ∞
V/Q mismatch w/ perfusion defects are often indicative of a
PE
Most commonly caused by DVT in the lower extremities that embolises to the pulm vasculature; presents w/ sudden SOB and pleuritic chest pain.
PE
The risk of Venous Thromboembolism (VTE) such as DVT or PE in hospitalized pts can be reduced with the admin of prophylactic
anticoagulants (LMWH)
Most definitive diagnostic test for PE
CT pulmonary angiography
Chest x-ray finding indicative of “pulmonary infarction” (not specific for PE though)
wedge-shaped infarction in the periphery of the lung
The combination of acute onset of dyspnea, calf swelling, and Hx of prolonged immobility is strongly suggestive of
PE
PE typically presents with what PaO2 and PaCO2 findings?
- Hypoxemia (low PaO2) due to V/Q mismatch with perfusion
- Respiratory Alkalosis (Hypocapnia or low PaCO2) due to hyperventilation
PE causes (shunt/dead space) V/Q mistmatch
dead space
The lungs are supplied by dual circulation from what two arteries which can help protect against lung infarction due to pulmonary artery occlusion?
- pulmonary arteries
2. bronchial arteries
Massive PE can lead to _____ due to a sudden loss of Cardiac Output
SCD
Type II pneumocytes have what 2 important functions?
- Regeneration of the alveolar lining following injury
2. Surfactant production
Secretory organelles found in type II alveolar cells store and release surfactant into the fluid layer lining the inner surfaces of alveoli; have foamy appearance
Lamellar bodies (aka. lamellar granules)
What is the major fxn of surfactant?
↓ surface tension in the fluid layer lining the inner surfaces of alveoli
Type I pneumocyte is (squamous/cuboidal)
squamous
Type II pneumocyte is (squamous/cuboidal)
clustered cuboidal
Pulmonary surfactant is majorly composed of what two types of Phospholipid?
- Lecithins (mainly dipalmitoyl phosphatidylcholine (DPPC)
2. Phosphatidylglycerol
Measured in order to assess fetal lung maturity
Amniotic fluid lecithin to sphingomyelin ratio (L/S ratio)
Fetal surfactant concentration don’t reach sufficient amount until week
35
Stimulate fetal lung maturation and surfactant production
corticosteroids
Administered to pregnant women at risk of premature delivery to prevent neonatal respiratory distress syndrome; administered at least 48 hours before delivery
corticosteroids
- Betamethasone
- Dexamethasone
Fetal lung lecithin (DPPC) production increases when?
after 30 weeks gestation
Fetal lung phosphatidylglycerol production increases when?
at 36 weeks gestation
The binding of O2 to hemoglobin increases the affinity for binding of subsequent O2 molecules
cooperative binding
In the “lungs”, the binding of O2 to hemoglobin drives the “release” of H+ and CO2 from hemoglobin
Haldane effect
- STUDY AID: HaLdane in the Lungs
In the “peripheral tissues”, high concentrations of CO2 and H+ facilitate “O2 unloading” from hemoglobin
Bohr effect
*STUDY AID: Bohr in the Body
Bohr effects shifts O2 dissociation curve to the ___; decreased affinity of the hemoglobin for oxygen and hence an increased tendency to give up oxygen to the tissues
right
Three forms of CO2 when it gets transported from tissues to LUNGS
- HCO3- (bicarbonate)
- HbCO2 (Carbaminohemoglobin; CO2 bound to Hb at N-terminus of globin, not heme)
- Dissolved CO2
The majority of CO2 produced in the tissues is transported to the lungs as what form?
HCO3- (bicarbonate)
*70%
Enzyme that forms HCO3- from CO2 and water
Carbonic Anhydrase
What ion gets exchanged as excess HCO3- gets transferred out of RBCs into the plasma
Cl-
*aka. Cl- shift
BOTH perfusion (Q) and ventilation (V) are highest in the ____ of the lung.
base
V/Q ratio at the base of the lung
V/Q = 0.6
- wasted perfusion
BOTH perfusion (Q) and ventilation (V) are lowest in the ____ of the lung.
apex
V/Q ratio at the apex of the lung
V/Q = 3
*wasted ventilation
V/Q ratio at the apex of the lung
V/Q = 3
*wasted ventilation
↑ Respiratory rate (hyperventilation) effect on blood pH
pH increases
- More CO2 gets blown off
↓Respiratory rate (hypoventilation) effect on blood pH
pH decreases
- Less CO2 gets blown off
Hyperventilation response typically leads to respiratory
alkalosis (low PaCO2)
Presents with a low pH and a high PaCO2
respiratory acidosis
What is the change in HCO3- level in the blood in respiratory acidosis?
HCO3- initially remains within the normal range, but increases over hrs to days as “renal” compensation develops
Presents with altered level of consciousness, pinpoint pupils, and central respiratory depression; Pts are expected to have acute respiratory ______ due to hypoventilation; serum HCO3- is typically near normal as there isn’t time for meta compensation in the “acute” setting
Acute opioid overdose; acidosis (low pH, high PaCO2)
Volume of inspired air that does not participate in gas exchange
Physiologic dead space
Physiologic dead space consists of what two types of spaces?
- Anatomic dead space
- Alveolar dead space
- Physiologic dead space = Anatomic dead space + Alveolar dead space
the volume of air in the conducting zone (mouth, trachea, bronchi) that doesn’t participate in gas exchange
Anatomic dead space
the sum of the volumes of alveoli that do not participate in gas exchange (mainly APEX of the lungs)
Alveolar dead space
The change in physiologic dead space during exercise caused by vasodilation of the pulmonary vessels in the apices of the lungs
Decreased physiologic dead space due to decreased alveolar dead space
NRDS presents with what respiratory symptoms/signs?
Nasal flaring Rapid breathing Subcostal retractions Decreased breathing sound Grunting Cyanosis
NRDS presents with what chest X-ray findings?
- Diffuse ground-glass (reticular) opacities
- Air bronchogram (air-filled bronchi on a background of airless lung)
NRDS presents with what lung BIOPSY finding?
Hyaline membranes lining the alveoli
- Amniotic fluid L/S ratio indicating lung maturity is _____.
- Amniotic fluid L/S ratio indicating a higher risk of developing NRDS is ____.
- > 2
2. < 1.5
NRDS decreases what lung volumes?
ALL (including Functional Residual Capacity)
The effect of rib fracture on tidal volume & lung compliance
- Decreased TV (due to pain)
- Normal Lung Compliance
- Rib fracture is NOT equal to pneumothorax (but can cause pneumothorax if punctured through the lung parenchyma)
The effect of exercising on CO, PaCO2, PaO2, and pH
CO: increased (↑HR, ↑SV)
PaCO2: normal
PaO2: normal
pH: decreased (lactic acid production)
PaCO2 is normal during exercise b/c CO2 washout is offset by
CO2 production in exercising muscles
PaO2 is normal during exercise b/c higher O2 consumption is offset by
increase in oxygenation (through increased breathing)
Risk factors for DVT
long air flight pregnancy advanced age smoking Estrogen
The effects on PaCO2 and PaO2 by the respiratory center depression due to drugs (barbiturates, opioids)
PaCO2: increased (>45)
PaO2: decreased
*hypoventilation
How would hypoventilation due to barbiturates or opioids change A-a gradient?
Normal A-a gradient b/c PAO2 would also decrease due to an increase in PaCO2
*PAO2 = PIO2 - (PaCO2/R)
PAO2 = 150 mmHg - (PaCO2/0.8)
What lung disease presents with bronchial (loud, harsh) breath sounds?
Consolidation (when lung parenchyma is filled w/something other than air)
What presents with decreased breath sounds
Every other lung pathology
Describe breath, percussion, and fremitus (vibration) sound findings for pneumothorax
Breath: Decreased
Percussion: Hyperresonant (loud)
Fremitus: Decreased
Trachea will deviate (toward/away from) side of lesion in tension pneumothorax
away from
- simple pneumothorax has no tracheal deviation
Describe breath, percussion, and fremitus (vibration) sound findings for Atelectasis
Breath: Decreased
Percussion: Dull
Fremitus: Decreased
Trachea will deviate (toward/away from) side of lesion in Atelectasis
Toward
Describe breath, percussion, and fremitus (vibration) sound findings for Pleural Effusion
Breath: Decreased
Percussion: Dull
Fremitus: Decreased
Trachea will deviate (toward/away from) side of lesion in Pleural Effusion
Away from if large
- None if small
Describe breath, percussion, and fremitus (vibration) sound findings for Consolidation (pneumonia, pulmonary edema)
Breath: Bronchial sound
Percussion: Dull
Fremitus: Increased
Trachea will deviate (toward/away from/none) side of lesion in lung consolidation
NONE
- no tracheal deviation with lung consolidation
What lung disease/pathology only presents with INCREASED fremitus while others present with decreased fremitus?
Consolidation
What lung disease/pathology only presents with bronchial (loud, harsh) breath sounds while others present with decreased breath sounds?
Consolidation
What lung disease/pathology only presents with hyperresonant percussion while others present with dull percussion
Pneumothorax
A syndrome that is the consequence of a tumor in the body (usually a cancerous one) due to the production of hormones or cytokines by that tumor
Paraneoplastic syndrome
What lung cancer is associated with several paraneoplastic syndromes?
Small Cell Lung Carcinoma
The most common cause of syndrome of inappropriate antidiuretic hormone (SIADH) due to “ectopic” secretion of antidiuretic hormone; SIADH is characterized by hyponatremia, decreased serum osmolality, and urine osmolality >100 mOsm/kg H2O
Small Cell Lung Carcinoma
The risk factor strongly associated with SCLC
smoking
SCLC is (peripherally/centrally) located in the lungs
Centrally
Cells that appear on histopathology of SCLC
small cells with dark blue nuclei
- aka. Kulchitsky cells
SCLC have + IHC stains for what neuroendocrine markers?
- Chromogranin A
- Synaptophysin
- Neuron-Specific Enolase
The most aggressive type of lung cancer
SCLC
The origin of SCLC
neuroendocrine cell
Ectopic hormones/antibodies produced by SCLC (3)
- ACTH (Cushing syndrome)
- ADH (SIADH)
- Presynaptic ca+2 channel antibodies (Lambert-Eaton)
SCLC is aka.
Oat Cell Carcinoma
SCC is (peripherally/centrally) located in the lungs
Centrally
What lung cancer presents with hypercalcemia?
Squamous Cell Carcinoma
SCC is (peripherally/centrally) located in the lungs
Centrally
The risk factor strongly associated with SCC
smoking
Histopathology findings associated with SCC
Intercellular bridges (desmosomes) & Keratin pearls
A systemic autoimmune disorder characterized by non-caseating granulomas in a variety of tissues; presents in young AA women w/ the “insidious” (slow/months) onset of respiratory symptoms (NONPRODUCTIVE cough, dyspnea) accompanied by systemic conditions (fatigue, fever, and weight loss)
Sarcoidosis
Sarcoidosis is majorly mediated by what immune cell that release cytokines to activate macrophage and granuloma formation?
CD4+ T cell
Cytokine released by CD4+ T-cell to drive macrophage activation and granuloma formation in sarcoidosis
IFN-γ
What consists of aggregates of epithelioid macrophages (activated macrophages) and multinucleated giant cells?
non-caseating granulomas of sarcoidosis
Skin findings associated with systemic Sarcoidosis
- Erythema Nodosum
* HINT: red mosquito-bite like nodules on shins - Lupus Pernio
* HINT: face lesions resembling lupus malar rash
A sarcoidosis patient that presents with hepatomegaly w/ LFT abnormality likely has sarcoidosis involvement of ____, and biopsy of this organ will demonstrate
liver; scattered non-caseating granulomas
Tx of choice for symptomatic sarcoidosis
Oral steroids (prednisone)
Non-caseating granulomas (are/are NOT) infectious
are NOT
- NCGs are immune-produced (autoimmune)!
Chest imaging (x-ray, CT) findings of sarcoidosis
- Bilateral HILAR Lymphadenopathy
- Lung opacities
What stimulates the differentiation of Th1-type CD4+ T cells, leading to NCG formation?
Antigen-presenting cells producing “IL-12”
(Hypercalcemia/Hypocalcemia) can present in sarcoidosis due to ↑ 1a-hydroxylase-mediated vitamin D activation in macrophages
Hypercalcemia
- ↑ 1a-hydroxylase –> ↑ activated vitamin D –> ↑ intestinal absorption of Ca2+ –> Hypercalcemia
What facial muscle weakness or paralysis is associated with Sarcoidosis?
Bell Palsy
Normal serum calcium level
8-10
What serum enzyme (produced in the lung) level is increased in Sarcoidosis?
ACE (angiotensin-converting enzyme)
What is elevated in BAL (bronchoalveolar lavage) in Sarcoidosis?
CD4+ T cell count
- (CD4+/CD+8 ratio to be exact)
Activated macrophages secrete what cytokine to aggregate into giant cells to form a granuloma in sarcoidosis?
TNF-a
A peripheral lung carcinoma (predominantly NON-small cell lung cancer) that can compress structures including the recurrent laryngeal nerve (causes hoarseness), the stellate ganglion (causes Horner syndrome), the superior vena cava (causes superior vena cava syndrome), the brachiocephalic vein (causes brachiocephalic syndrome), and the brachial plexus (causes sensorimotor deficits)
Pancoast Tumor
Pancoast tumor is usually located where in the lung?
superior sulcus (apex) of the lung
The most common “1°” lung cancer in the general population, women, and NON-smokers
Adenocarcinoma
Lung cancer that is characterized histopathologically by mucin-producing glandular tumor cells with abundant cytoplasm and eccentrically placed nuclei
Adenocarcinoma
Adenocarcinoma is (peripherally/centrally) located in the lungs
peripherally
Two mutations most likely associated with adenocarcinoma in NON-smokers
- EGFR gene mutation
2. ALK gene translocation
Biopsy of lung adenocarcinoma caused by ALK mutation has what cell likely to be seen histopathologically in addition to glandular cells?
signet ring cells producing mucin
Lung scar is associated with the increased risk of developing what pulmonary malignancy?
Lung Scar Carcinoma (aka. Adenocarcinoma)
Scarring from ______ is the most common risk factor for Lung Scar Carcinoma due to chronic inflammatory response leading to persistent DNA damage and oncogene activation, resulting in neoplastic transformation
TB
Lung Scar Carcinoma has (better/worse) prognosis compared to lung carcinoma not associated with scars
Worse
Round nodules of VARYING sizes scattered throughout the lungs suggest; described as “cannonball lesions”
pulmonary metastases
Three primary tumors that is highly associated with pulmonary metastases
- Breast
- Colorectal
- Renal
Compression of _______ by pancoast tumor leads to Horner syndrome (ipsilateral symptoms)
- STUDY AID: PAM is Horny
- ptosis
- Anhidrosis
- Miosis
stellate ganglion
The types of Lung cancer most strongly associated with cigarette smoking
SCLC & SCC
A paraneoplastic syndrome characterized by digital clubbing, arthritis, and painful joint swelling (periostitis) associated with lung adenocarcinoma
Hypertrophic Osteoarthropathy (HOA)
A paraneoplastic autoimmune disease caused by SCLC (produce antibodies against presynaptic ca+2 channels); characterized by muscle weakness that “improves” with repetitive stimulation and “decreased” deep tendon reflexes
Lambert-Eaton Myasthenic Syndrome
How does Squamous Cell Carcinoma cause hypercalcemia?
SCC increase the production of parathyroid hormone-related protein –> stimulation of PTH receptors –> increase Ca+2 –> Hypercalcemia & Hypophosphatemia
The most common cause of a benign SOLITARY pulmonary nodule; described as “coin” lesion (well-circumscribed, calcified)
Pulmonary hamartoma
Pulmonary hamartoma is (centrally/peripherally) located in the lung
peripherally
Histology of pulmonary hamartoma will show disorganized ______ in fibromyxoid tissue with clefts of ciliated epithelium
hyaline/cartilage
Airway resistance is highest in what region of respiratory tree?
Medium sized bronchi
Airway resistance is lowest in what region of respiratory tree?
terminal bronchioles (large numbers)
Cell type making up epithelium of bronchi
Ciliated Pseudostratified columnar cells
Cell type making up terminal and respiratory bronchioles
Ciliated Simple Cuboidal cells
The number of goblet cells and amount of cartilage decreases distally, ending BEFORE ______; still lined with smooth muscle
terminal bronchioles
“Ciliated” epithelium persists up to the _______; lacks smooth muscle
respiratory bronchioles
Starting from what region of bronchioles is considered respiratory zone and participates in gas exchange?
respiratory bronchioles
Maximum volume of air that can be present in lungs
Total Lung Capacity (TLC)
Air that moves in and out with each passive breathing
Tidal Volume (TV)
Tidal Volume is usually
500 mL
Maximum volume of air that can be expired after a maximal inspiration
Vital Capacity (VC)
Air in lung that remains after maximum expiration
Residual Volume (RV)
Air that can be forcefully breathed out after normal expiration (TV)
Expiratory Reserve Volume (ERV)
Air that can be forcefully breathed in after normal inspiration (TV)
Inspiratory Reserve Volume (IRV)
Maximum volume of air that can be inspired after a normal expiration
Inspiratory Capacity (IC)
Volume of air in lungs after normal expiration (TV)
Functional Residual Capacity (FRC)
Type (I or II) pneumocytes will increase in response to lung injury/damage
Type II (which will eventually differentiate into Type I)
The symptoms of asthma are primarily caused by inflammation of what airway region b/c it lacks cartilage leading to collapsing of airways?
terminal bronchioles
The primary mechanism of particle clearance in trachea and bronchi
mucociliary escalator
*cilia in the respiratory tract direct mucus and debris toward the pharynx
The primary mechanism of particle clearance in alveoli
alveolar macrophages
The primary mechanism of particle clearance in nasal cavity
Nasal vibrissae (hair)
An enzyme secreted by alveolar macrophages and neutrophils that plays a role in the degradation of elastin (extracellular matrix) in the lungs
metalloproteinases (Elastase to be specific)
(Restrictive/Obstructive) lung disease is when it’s hard to get air out of the lungs
Obstructive
(Restrictive/Obstructive) lung disease is when it’s hard to get air into the lungs
Restrictive
Maximum air that can be exhaled in 1 second
Forced Expiratory Volume 1 (FEV1)
Maximum air that can be exhaled after maximum inhalation
Forced Vital Capacity (FVC)
FEV1/FVC ratio for obstructive lung disease; explain why
FEV1/FVC <0.7
- b/c FEV1 will decrease since you can’t get air out
FEV1/FVC ratio for restrictive lung disease; explain why
FEV1/FVC >0.7
- b/c FVC will decrease since you can’t get air in
Examples of Obstructive Lung Disease
- COPD
- Emphysema
- Bronchiectasis
- Asthma
Examples of Restrictive Lung Disease
- Interstitial Lung Disease
- Environmental Pneumoconioses (asbestosis silicosis, coal, etc.)
- ARDS
- Sarcoidosis
- think of diseases that can cause fibrotic lung
STUDY AID to remember Obstructive Lung Disease
OBstrUct
- O: out (air can’t get out)
- B: below (FEV1/FVC ratio is below 0.7)
- U: upper (numerator is decreased)
STUDY AID to remember Restrictive Lung Disease
REstrIct
- R: r”inside” (air can’t get in)
- E: elevated (FEV1/FVC ratio is above 0.7)
- I: inferior (denominator is decreased)
MOA of ipratropium (anticholinergic agent) for obstructive lung disease including COPD and asthma
Inhibits M3 receptors in lungs from binding ACh to prevent bronchoconstriction and mucus secretion
The flow-volume loop for _____ is changed by ↑ RV and TLC, as well as a “scooped-out” expiratory pattern due to ↓ expiratory flow rates
COPD
Permanent destruction of alveolar walls leading to ↓ elasticity in COPD lungs; responsible for the hyperinflation and airflow limitation
Emphysema
Airway narrowing responible for chronic production of cough in COPD
Chronic Bronchititis
Emphysema or destruction of alveolar walls in COPD is highly associated with chronic heavy smoking which leads to the imbalance of what enzymes produced by neutrophils and macrophages?
proteases vs. antiproteases
Increase in what “protease” enzyme leads to the loss of elastic fibers causing increased lung compliance in COPD?
Elastase
A combination of emphysema and chronic bronchitis; presents with wheezing, mucus production, and progressive cough/dyspnea
COPD
Thickened bronchial walls, mucous gland enlargement, and “squamous metaplasia” of the bronchial mucosa are histological features of
chronic bronchitis
Changes in PFT seen in COPD
↓ FEV1
↓ FEV1/FVC ratio
↑ RV
↑ TLC
The leading cause of chronic bronchitis
Tobacco smoking
The name of the ratio of the thickness of the submucosal bronchial glands to the thickness of the bronchial wall b/w the epithelial BM and the bronchial cartilage; higher values correlate with ↑ duration and severity of chronic bronchitis
Reid Index ratio
(PaO2/PaCO2) is the major stimulator of respiration in HEALTHY individuals.
build up of PaCO2
(PaO2/PaCO2) is the major stimulator of respiration in COPD individuals.
decreased PaO2 (hypoxemia due to decreased gas diffusion)
The best tx for COPD; it can slow the accelerated decline in FEV1, but FEV1 won’t return to normal
smoking cessation
Most COPD exacerbations are triggered by
URIs
An homeostatic mechanism in which intrapulmonary arteries constrict in response to alveolar hypoxia, diverting blood to better-oxygenated lung segments, thereby optimizing ventilation/perfusion matching and systemic oxygen delivery
Hypoxic Pulmonary Vasoconstriction
A serum protein that inhibits neutrophil elastase to ↓ tissue damage in lungs; has anti-protease activity
a1-antitrypsin
A disease that causes an increased risk of having lower lobe emphysema and liver disease due to lack of a1-antitrypsin protein
a1-antitrypsin deficiency
Exposure to _____ dramatically accelerates the development of emphysema in pts with a1-antitrypsin deficiency
tobacco smoke
What would be seen on LIVER histology of a1-antitrypsin deficiency patients?
Hepatocytes filled with red globules that represent un-secreted, polymerized a1-antitrypsin proteins
- a1-antitrypsin protein is made in the liver but can’t be secreted out of the liver
Patients with emphysema/COPD will have (increased/decreased/normal) Diffuse Lung Capacity for Carbon Monoxide (DLCO)
decreased
COPD/emphysema patients have chronic CO2 retention in addition to hypoxemia b/c of decreased
diffusing capacity due to destruction of alveolar wall
An umbrella term used for a large group of diseases that cause scarring (fibrosis) of the lungs; caused by repetitive injury and disordered healing –> decreased lung compliance/volumes and increased lung elastic recoil
interstitial lung disease (ILD)
aka. Pulmonary fibrosis
Changes in PFT seen in Interstitial Lung Disease
↓↓ FVC
↓ FEV1
↓ TLC
↑ FEV1/FVC ratio
- RV stays the same
Patients with interstitial lung disease (ILD) presents with what pattern of breathing?
short, shallow breaths
Histologic findings of interstitial lung disease (ILD)
will show
- Patchy interstitial inflammation intermixed w/ areas of dense fibrosis and normal lung
- Fibroblastic proliferation
- Fibrous and cystic honeycomb spaces
- simply put => Excess collagen deposition in the extracellular matrix
Patients with (Restrictive/Obstructive) Lung Disease will minimize the work of breathing by increasing respiratory rate (RR) at a lower TV; fast, shallow breaths
Restrictive
Patients with (Restrictive/Obstructive) Lung Disease will minimize the work of breathing by decreasing respiratory rate (RR) at a higher TV; slow, deep breaths
Obstructive
Pneumoconioses (coal workers, silicosis, asbestosis) are (restrictive/obstructive) lung disease
Restrictive
Sarcoidosis is (restrictive/obstructive) lung disease
Restrictive
Lung damage due to drug toxicity is usually (restrictive/obstructive) lung disease
Restrictive
Patients with restrictive lung disease will have (increased/decreased/normal) Diffuse Lung Capacity for Carbon Monoxide (DLCO)
decreased
Digital clubbing is seen in what obstructive lung disease?
bronchiectasis
Digital clubbing is most likely to be seen in what restrictive lung disease?
Idiopathic pulmonary fibrosis
Characterized by luminal narrowing of the pulmonary arteries and arterioles, resulting arterioslcerosis, medial hypertrophy, intimal fibrosis, and plexiform lesions; usually idiopathic, affects young women but can be familial
Pulmonary arterial hypertension (PAH)
Hereditary PAH Pulmonary arterial hypertension is due an inactivating mutation of ______ gene, which normally inhibits vascular smooth muscle proliferation
BMPR2
- Bone Morphogenetic Protein Receptor Type 2
Pulmonary vasculature endothelial dysfunction due to BMPR2 gene mutation results in ↑ ______ and ↓_________
vasoconstrictors (endothelin); vasodilators (prostaglandins)
A competitive antagonist of endothelin receptors used for the treatment of PAH
- Bosentan
- Ambrisentan
The most common malignancy in patients with a long history of asbestos (ship building, drywall application) exposure
Bronchogenic Carcinoma (aka. lung cancer)
- However, mesothelioma is more specifically associated with asbestos
A neoplasm arising from pleural mesothelial cells and is strongly associated with asbestos exposure; presents with dyspnea, cough, and chest pain; multiple nodules form on the parietal pleura and gradually encase the lung parenchyma
Mesothelioma (pleural tissue)
- Mesothelioma is not a lung cancer (lung tissue)!
Unilateral _______ thickening or plaque formation is seen on imaging of mesothelioma
Pleural
Histology of mesothelioma will show
Tumor cells with numerous long, slender microvilli and abundant tonofilaments (intermediate filaments)
IHC stains (2) used for the diagnosis of mesothelioma
+ cytokeratin and + calretinin
*nearly all mesotheliomas stain positive for these two!
Asbestos fibers (coated gold with iron) that appears on asbestosis histology
Ferruginous body
Affected asbetos patients remain Asymptomatic for about how many years following initial exposure?
20-30 years
Excess fluid accumulation between pleural layers (visceral pleura that lines the lungs and the parietal pleura that lines the thoracic cavity) –> restricted lung expansion during inhalation
Pleural effusion
Tactile fremitus, intensity of breath sounds, and percussion for pleural effusion
All ↓
______ effusion is typically caused by ↓ serum protein content leading to increased hydrostatic or decreased oncotic pressure
Transudative
______ effusion typically presents with ↑ serum protein content caused by inflammation/infection and consequent ↑ vascular membrane permeability
Exudative
Which type of pleural effusions present with clear fluid?
Transudative
*STUDY AID: “Transudative effusion has transparent (clear) fluid”
Which type of pleural effusions present with cloudy fluid?
Exudative
______ effusion typically presents with milky fluid
(↑ triglycerides) caused by thoracic duct injury from trauma or malignancy
Lymphatic
- aka. Chylothorax
Thoracentesis is placed through the skin and subcutaneous fat into the _______ intercostal space in the anterior axillary or midaxillary line
4th or 5th
Which type of pleural effusions must be drained due to risk of infection?
Exudative
The most common sleep-related breathing disorder characterized by recurrent obstruction of the upper airways; relaxation of the oropharyngeal muscle during sleep results in blocking of the airway; associated with HTN
Obstructive Sleep Apnea (OSA)
Presents in obese individuals with excessive daytime sleepiness, snoring, gasping due to nocturnal upper airway obstruction
Obstructive Sleep Apnea (OSA)
Prolonged, untreated OSA ↑ risk for what 2 complications besides HTN?
- Right Heart Failure
- Pulmonary Arterial Hypertension
Electrical stimulation of what nerve increases the diameter of the oropharyngeal airway and decreases the frequency of apneic events in OSA?
Hypoglossal nerve (CN12)
Abscess formation is largely driven by ______ recruitment and activation leading to the release of cytotoxic granules that kill bacteria but also cause liquefying necrosis of surrounding tissue
Neutrophil
Most often due to “aspiration” of ANAEROBIC (+aerobic) oral bacteria; risk factors that ↑ aspiration of anaerobes include alcoholism, drug abuse, previous stroke, and dementia
Lung abscess
The most likely factor that increases the risk of lung abscess due to the aspiration of oral flora during periods of unconsciousness
Alcoholism
What antibacterial drug provides coverage against both anaerobic and aerobic organisms and has been traditionally used in the treatment of lung abscess?
Clindamycin
*Lincosamide
HF and Na+ retention are examples of (↑ hydrostatic pressure/↓ oncotic pressure)
↑ hydrostatic pressure
Nephrotic syndrome and cirrhosis are examples of (↑ hydrostatic pressure/↓ oncotic pressure)
↓ oncotic pressure
Hypoxia in OSA (apneic episodes) or COPD can lead to hypoxic pulmonary vasoconstriction that can INCREASE what pressure?
pulmonary pressure
Increase in pulmonary pressure due to hypoxic pulmonary vasoconstriction can cause what heart dysfunction?
Right Ventricular Dysfunction
- Right Heart Failure
Impaired functioning of the right ventricle caused by high pressure in pulmonary arteries is medically known as
cor pulmonale
*RHF caused by pulmonary hypertension
Pleural fluid LDH >2/3 of the upper limit of normal serum LDH indicates which type of pleural effusion?
Exudate
Pleural fluid LDH <2/3 of the upper limit of normal serum LDH indicates which type of pleural effusion?
Transudate
An umbrella term to describe an elevated mean pulmonary arterial pressure (>25 mm Hg at rest) caused by different etiologies including pulmonary arterial hypertension and chronic hypoxia (OSA, COPD)
Pulmonary Hypertension
- pulmonary arterial hypertension is an etiology causing pulmonary hypertension
Scratchy, high-pitched breath sounds on lung auscultation indicates
friction rub of pleuritis
Hypoxia can trigger renal erythropoietin secretion leading to increased RBC production in the bone marrow, and this results in what skin presentation?
facial red discoloration (plethora)
Peptostreptococcus, Prevotella, Bacteroides, and Fusobacterium are the most common oral _________ bacteria causing lung abscesses
anaerobic
What lung disease is most likely to occur in a patient with a history of asbestos exposure with the CT finding of pleural plaques?
lung cancer
- pleural plaques is a presentation of asbestosis and is NOT specific for mesothelioma (not a lung cancer)!
Which type of pleural effusions will present with decreased pleural fluid glucose level?
Exudative (increased metabolism of glucose by bacteria)
Pulmonary hypertension will present with what heart sound?
- HINT: due to increased right ventricular afterload
Split S2 (Loud P2)