Pulm Week 2 Flashcards
Obstructive lung disease is caused by airway narrowing due to… (2)
1) Intrinsic airway narrowing (bronchospasm, plugging, inflammation/edema
2) Collapse (“floppy” airways) - decreased radial tethering or decreased airway integrity
Obstructive disease has increased lung volumes due to _______ and results in…(2)
due to incomplete emptying of alveoli - hard to exhale
1) Hyperinflation → increases RV, ERV, and thus FRC by decreasing IC
2) Flattening of the diaphragm → mechanical disadvantage
(Flat diaphragm generates less inspiratory pressure due to increased radius of curvature AND must generate more tension in order to generate same intrapleural pressure)
Increased airway resistance in obstructive disease result in…
increased work of breathing
Bronchoprovocation testing in asthma, vocal cord dysfunction, and emphysema
Asthma: REVERSIBLE
- Should go completely back to normal with bronchodilator
- Methacholine challenge: people with asthma react at level of 5 or less
Vocal Cord Dysfunction: minimally reversible with bronchodilator
Emphysema: no reversibility to bronchodilators
Asthma
- chronic inflammation of airways associated with airway hyperresponsiveness
- Recurrent episodes of wheezing, breathlessness, chest tightness, and coughing particularly at night or in the early morning
- Episode associated with airflow obstruction that is reversible spontaneously or with treatment
Types of asthma (Extrinsic vs. Intrinsic)
Extrinsic (Allergic): initiated by type I hypersensitivity reaction induced by exposure to an outside agent
-Mostly IgE mediated
Intrinsic (nonseasonal, nonallergic): initiated by diverse, non-immune mechanisms (ASA ingestion, viral infection, cold, inhaled irritants, stress, exercise)
- Chronic, persistent
- Altered arachidonic acid metabolites (increases leukotrienes, decreased prostaglandins - ASA)
Airway narrowing in asthma occurs due to…
Inflammation: inflammatory cells + inflammatory mediators
Structural airway changes
Structural airway changes in asthma (3)
1) Increase in airway smooth muscle cells due to hypertrophy and hyperplasia
2) Blood vessel proliferation
3) Mucus hyper-secretion (increased goblet cells and size of submucosal glands)
Clinical features of asthma (7)
1) Intermittent - PFTs can be normal between exacerbations
2) Reversibility of airflow obstruction
3) Cough, dyspnea, wheezing
4) Exacerbations with exposure to: exercise, cold air, allergens, air pollution, infection
5) Normal to increased DLCO
6) Bronchoprovocation demonstrates hyperreactivity
7) Severity of asthma determines by frequency of symptoms
Physical exam findings in asthma (3)
- May be normal in stable disease
- Respiratory distress: increased rate, use of accessory muscles
- Wheezing (expiratory)
- Distinguish inspiratory stridor (VCD) from expiratory wheezing (asthma)
Acute asthma
1) Hyperinflation
(shortened diaphragm)
2) Breathing occurs on flatter part of PV curve - more pressure required to get similar change in volume
3) Accessory muscle use
4) INCREASED WORK OF BREATHING
5) Can improve symptoms with bronchodilation → facilitates exhalation
Pathology of airways during acute asthma
Airway inflammation, edema, and mucus plugging lead to gas trapping and airflow obstruction in acute asthma
→ unable to fully exhale before taking next breath → breaths “stack” up on one another → increase lung volumes
Vocal cord dysfunction
inappropriate vocal cord motion results in airflow obstruction
Variable extrathoracic obstructive pattern due to adduction of vocal cords during inspiration
Physical exam findings in VCD
Symptoms mimic asthma (share similar triggers also) - Often coexists with asthma
- Stridor mistaken for wheezes - stridor = inspiratory
- Flow-volume loop suggestive (extrathoracic obstructive pattern)
- Diagnosed by fiberoptic laryngoscopy
Treatment of VCD
Acute: anxiolytics, helium-oxygen mixture
Long term: speech therapy, underlying triggers
COPD
fixed airflow limitation, FEV1/FVC less than 70%
3rd leading cause of death in the US
Smoking is a big risk factor
Chronic Bronchitis
Increased airway resistance due to changes in airway structure (edema, mucous, fibrosis)
-May have overlapping features with asthma
- Produces TONS of mucous
- -> Impaired ventilation
Diagnosis of chronic bronchitis
Productive cough at least 3 months over the past 2 years without other cause
Physical exam findings of chronic bronchitis (4)
1) *Cough, rhonchi, wheezing
2) Prolonged expiratory phase
3) Purse-lip breathing
4) Tripod positioning
Emphysema
- Loss of normal alveolar spaces with enlargement of distal airspaces
- Increased lung compliance
- Impaired gas exchange
- Dynamic airway collapse
What causes increased lung compliance in emphysema?
- Decreased elastic tissue
- Loss of balance between proteases and antiproteases in lung (alpha-1-antitrypsin deficiency)
- Increased apoptosis of alveolar cells
- Impaired repair mechanisms
What causes dynamic airways collapse in emphysema?
“floppy” airways and loss of elasticity of surrounding tissue allow for collapse
Physical exam findings in emphysema (5)
1) *Diminished breath sounds
2) *Hyper-resonant
3) Prolonged expiratory phase
4) Purse-lip breathing
5) Tripod positioning
Acute COPD exacerbation
- Increased cough, sputum volume and purulence, increased wheezing
- Worsening obstruction on PFTs
- Unchanged CXR
- Precipitated by infection, pollution PE, or unknown factors
Implications:
-Increased work of breathing due to hyperinflation, increased airway resistance
Treatment of acute COPD exacerbation
Bronchodilators, steroids, antibiotics
Common causes of death from COPD (5)
Respiratory failure Right ventricular failure Pneumonia Spontaneous pneumothorax Pulmonary embolism
Bronchiectasis
abnormal dilation of proximal bronchi
- Localized or diffuse
- Mucociliary escalator stops working
- Loss of airway wall integrity with dilation → collapsible airways result in obstruction (may be compounded by inflammation)
- Recurrent infections worsen bronchiectasis (CF, PCD, immunodeficiency)
Symptoms of bronchiectasis (4)
1) Cough, productive of purulent sputum
2) Sputum volume often copious (especially during exacerbation)
3) Wheezing, hemoptysis
4) Mild airflow limitation
Treatment of bronchiectasis
- Airway clearance to promote clearance of secretions
- Antibiotics (intermittent, chronic, rotating courses)
-Treat reactive airways disease
(Bronchodilators, corticosteroids)
Bronchiolitis
inflammation of the bronchioles
-usually occurs in young children
Cystic Fibrosis
- Heterogeneous recessive genetic disorder
- Mutation in cystic fibrosis transmembrane conductance regulator (CFTR) gene at locus 7q31.2
- Normal protein function: CFTR chloride channel in membranes of cells that line passageways of lungs, liver, pancreas, intestines, reproductive tract, and skin
Factors that influence development of asthma
1) Host factors (genetic predisposition to atopy or airway hyperresponsiveness, obesity, sex)
2) Environmental factors (exposure to allergens, viral infection, occupational exposures, tobacco smoke, air pollution, diet)
Differentiating chronic bronchitis, asthma and emphysema
Chronic Bronchitis: inflammation of the airways themselves
- Chronic productive cough
- Minimal reversibility (under stable conditions) with albuterol
- Normal to slightly increased DLCO
Asthma: increase in smooth muscle tone and airway inflammation
- Reversible, episodic
- Exacerbation with methacholine
- Normal to increased DLCO
Emphysema:
- Marked hyperinflation (due to tissue destruction)
- No reversibility to bronchodilators
- Decreased DLCO
- Shift in PV curve
Challenges delivering inhaled drugs
1) Airway bifurcations limit inhaled delivery
2) Entire blood volume contacts lungs → toxicity, also better drug efficacy
3) Particle size - Med must be contained within particles small enough to be aerosolized
-small enough to be inhaled and avoid the pharynx and reach small airways
-can’t be too small or they will be exhaled back out
[Respirable range = 1-5 um]
Benefits of inhaled (topical) drug
- Preferred over systemic route because delivery directly to site of action (bypasses need for absorption)
- Smaller doses required, rapid onset
- Minimize systemic onset
goals of asthma treatment
-reduce frequency and intensity of asthma symptoms, prevent exacerbations, and prevent long term consequences of poorly controlled asthma
Stepwise treatment of ashma
- Gradual increase in medications to control symptoms
- Need regular follow up (2-6 weeks) when initiating therapy
- Must ensure asthma control is achieved
Step down is IMPORTANT - minimum dose necessary to control symptoms and prevent adverse effects
-Step down if well controlled for 3 months
Steps of Asthma treatment: Step 1 - Step 5
Step 1: SABA as needed
Step 2: low dose ICS
Step 3: combination therapy: SABA + medium dose ICS + LABA
Step 4: High dose ICS + LABA +/- Omalzumab
Step 5: high dose ICS + LABA + oral corticosteroid +/- Omalzumab
What is well-controlled asthma?
- Symptoms no more than twice per week
- Nighttime symptoms no more than twice per month
- SABA should be used less than twice weekly (with exception of routine use prior to exercise)
- Peak flow near normal
- Oral steroid no more than once per year
- Urgent care visit no more than once per year
Long acting asthma medications include…(3)
1) Inhaled glucocorticoids
2) Long-acting inhaled B2-agonists (LABA)
3) Leukotriene modifiers
Inhaled glucocorticoids
preferred long-term control medication for tx of persistent asthma
Inhaled corticosteroids can impact growth in children
Long-acting inhaled B2-agonists (LABA)
- preferred supplementary long-term control agent for use with inhaled glucocorticoids (step 2, added to inhaled GCs)
- Should NOT be used as monotherapy, do not reduce inflammation
- Combine with inhaled corticosteroid to control inflammation
Leukotriene modifiers
-2 mechanism of actions
Mechanism of Action:
1) Leukotriene D4 antagonist (montelukast, zafirlukast)
2) 5-lipoxygenase inhibitor (zileuton)
→ bronchodilation, anti-inflammatory (block leukotrienes), and attenuates exercise induced asthma
Omalizumab
anti-IgE biologic
- Inhibit IgE binding to IgE receptor on mast cells/basophils
- Decreasing IgE bound → decrease release of allergic response mediators
Mepolizumab
anti-IL-5 biologic
Inhibit cytokine (IL-5) responsible for growth, differentiation, recruitment, activation, and survival of eosinophils
Allergen Immunotherapy
induce specific allergen tolerance
More effective for allergic rhinitis and conjunctivitis than asthma
Tiotropium
long acting anticholinergic for use in asthma age > 12 yrs
Theophylline
- limited use due to adverse effect profile
- Oral or IV
Mechanism of Action: inhibit PDE
→ bronchodilation and some anti-inflammatory activity
Cromolyn sodium and nedocromil
- limited use, better current meds
- Inhaled
Mechanism of action: inhibit mast cell mediator release
→ prevent exercise-induced asthma and allergen-induced pulmonary response
Quick relievers for asthma (3)
1) Short acting B2 agonists (SABA)
2) anticholinergics
3) Systemic glucocorticoids
Short acting B2-agonists (SABA)
preferred to relieve symptoms and to prevent exercise induced asthma
Mechanism of Action: Stimulate B-adrenergic receptor → bronchodilation via smooth muscle relaxation, inhibits production of respiratory secretions
Anticholinergics
- use in COPD NOT asthma
- Secondary reliever for significant asthma exacerbations
Mechanism of Action: inhibit cholinergic receptor → bronchodilation via smooth muscle relaxation
Inhibits production of respiratory secretions
Systemic glucocorticoids
- for severe acute asthma exacerbations
- Sometimes for continued use in managing severe asthma
Systemic glucocorticoids mechanism of action
phospholipase inhibition, inhibition of cytokine synthesis
→ anti-inflammatory (Reduce cellular infiltration, eosinophils, mast cells, lymphocytes)
→ Vasoconstrictor, reduces edema
Classifying COPD
Gold 1 - Gold 4
all have FEV1/FVC less than 0.70
Gold 1, Mild = FEV1>80% predicted
Gold 2, Moderate = FEV1 between 50-80% predicted
Gold 3, Severe = FEV1 between 30-50% predicted
Gold 4, Very severe = FEV1 less than 30% predicted
Steps of COPD pharmacologic treatment (4)
A → SAMA or SABA prn
B → LAMA or LAMA prn
C → ICS + LABA or LAMA
D → ICS + LABA and/or LAMA
Treatment of COPD
1) Smoking cessation - creates capacity to influence COPD
- Can add pharmacotherapy and nicotine replacement to reduce smoking
2) Regular physical activity
Refer to pulmonary rehab to make patients more comfortable with exercise - typically for more severe/symptomatic COPD
3) Pharmacology (SAMA, SABA, ICS)
- No biologics used in COPD
Bronchial circulation
supplies conducting airways (trachea, down to terminal bronchioles)
Supplied by aorta and intercostal arteries
→ Arterial pressure and oxygenated blood
Function of bronchial circulation (3)
1) Perfuses the large airways
2) Protects lung from infarction (PE, pneumonia)
3) Can “grow into” areas of diseased lung
Consequence of bronchial circulation
Typical source of hemoptysis
Much of the arterial flow drains into LA = shunt
Equation of PAP
PAP = (CO x PVR) + LAP
Properties of pulmonary circulation (4)
- Low resistance
- Low elastance/High compliance
- Low pressure
- CO = 5L/min (same as systemic)
Progression of pulmonary circulation
R ventricle → pulmonary trunk → R and L main pulmonary arteries (carry deoxygenated blood) → lobar branches
→ muscular intrapulmonary arteries
→ arterioles (precapillary vessels)
→ Capillary network (alveolar ducts and alveoli)
→ Veins -Single lobar vein emerges from each lobe
Normal pressures in heart and lungs
RA = 0-5 mmHg RV = 25/0-5 mmHg PA = 25/10 mmHg LA = 5-10 mmHg LV = 100/5-10
RV diastolic pressure = right atrial pressure (no tricuspid valve stenosis)
RV systolic pressure = pulmonary artery systolic pressure (no pulmonary valve stenosis)
Determinants of blood flow distribution in the lung (4)
1) High capacitance (high distensibility of perfused vessels)
2) Recruitment of previously unperfused vessels (zone 1 and 2)
3) Hypoxic pulmonary vasoconstriction
4) Endogenous vasodilators and vasoconstrictors (NO, prostacyclin, endothelin, thromboxane)
Hypoxic pulmonary vasoconstriction
Vasoconstriction in areas with alveolar hypoxia
Preserves V/Q matching
Physiologic zones on the lung:
Zone 1
no blood flow
- PA > Pa → capillaries always collapsed
- Not present in a healthy person
- Can get this with mechanical ventilation with positive pressure ventilation or with COPD
Physiologic zones on the lung:
Zone 2
- Intermittent blood flow (PA>Pa, and Pa>PA)
- *Blood only flows when Pa>PA
- Vascular reserve when CO increases
- Some zone 2 will be present in normal healthy lung
- Apex of lung
Physiologic zones on the lung:
Zone 3
Continuous blood flow
Bottom of the lung
Pa always > PA → capillaries always open
Pulmonary edema
Normal fluid leak vs. pathologic fluid leak
fluid in the lung
Originates in capillaries → interstitium → lymphatics
-Too much fluid → alveolus → acinus fills with fluid, interlobular septa enlarges, and pulmonary vein enlarges
Normally: there is some net fluid out of the vessels, but it is returned to circulation by lymphatics
-No fluid enters the alveoli
Determinants of water and solute balance in the lung (2)
1) Hydrostatic (cardiogenic)
2) Increased permeability (noncardiogenic)
Hydrostatic Pressure (cardiogenic)
- **Increased vascular pressure (increased pulmonary capillary wedge pressure)
- LV failure, CHF
- **Diuretics help
- Presents within minutes of an acute elevation of microvascular pressure and rapidly responds to therapy
- Typically has a history of heart failure, EKG changes, chest pain
Increased permeability (noncardiogenic)
- Proteins leave vasculature
- Due to ARDS, pneumonia
- Presents more slowly (6-24 hours after acute lung injury)
- Associated with an exposure (e.g. toxic gas, trauma, fever, cough/pneumonia, aspiration of gastric contents)
- **PCWP not elevated
- **diuretics don’t help
Pulmonary Hypertension
pulmonary arterial pressure > 25 mmHg (normal is 15-18)
Increased PA pressure DOES NOT MEAN increased PVR
Causes of pulmonary HTN
1) Increased pulmonary vascular resistance (pre or postcapillary)
2) Increase LA pressure
3) Increased CO (Rarely by itself)
Difference between precapillary and postcapilarry pulmonary HTN
Precapillary: PCWP less than 15 mmHg
Postcapillary: PMWP > 15 mmHg
-Pulmonary venous hypertension (PVH)
5 types of pulmonary HTN
1) PAH = precapillary
2) PH due to left heart disease = PVH, postcapillary
3) PH due to lung disease and/or hypoxia (COPD, ILD, OSA)
4) Thromboembolic pulmonary HTN
5) PH with unclear/multifactorial mechanisms
Acute Pulmonary Embolism
clinical presentation
Results in RV strain or failure
-Increased myocardial O2 demand, decreased myocardial O2 delivery → cycle leading to death
Acute Pulmonary Embolism
diagnosis (7 tests)
1) History and physical → Wells’ scores (PE risk score)
2) D-Dimer (breakdown product of thrombin, elevated with active clot)
3) ECG - S waves in I, Q waves in III and T waves in III (SI, QIII, TIII)
- Most commonly sinus tach
4) **CXR - usually NORMAL
5) V/Q scan - measure mismatch between ventilation and perfusion
6) CT pulmonary angiography
7) Echo
Acute Pulmonary Embolism (stable aka submassive)
treatment
- Parenteral Anticoagulation
- -> Heparin (UFH, LMWH)
- Catheter directed thrombolysis (tPA)
- Oral anticoagulation (Warfarin)
Acute pulmonary embolism
(massive, RV failure, hypotensive)
treatment
- Heparin
- Consider thrombolysis (tPA)
- Consider IVC filter
- Consider surgical thrombectomy
3 criteria for Pulmonary Arterial Hypertension
mean PAP > 25 mmHg + PCWP/LVEDP less than 15, and PVR greater than 3 woods units
Chronic precapillary disease
Physical exam findings in PAH (7)
1) Neck veins distended
2) Normal lung auscultation (no rales, no fluid in alveoli)
3) Loud P2
4) Tricuspid regurg murmur
5) LE edema
6) **Presents with abnormally low DLCO with normal pulmonary function (lung volumes and spirometry)
7) **Does not increase pressure in pulmonary capillary bed and thus pulmonary edema does not develop
Hemodynamic and clinical course of PAH
1) CO normal, but PVR and PAP slowly increasing
- Asymptomatic
2) CO begins to decrease, PVR, PVP continue to rise, BNP begins to rise
- Some symptoms present
- -> Smooth muscle hypertrophy, early intimal thickening
3) CO falls off, PVR increases, PAP increases until it drops due to heart failure, BNP elevated
- -> Smooth muscle hypertrophy, adventitial, intimal proliferation, thrombosis, plexiform lesions
Treatment of PAH
1) Treat underlying cause (liver disease, HIV, etc.)
2) Correct hypoxia
3) Control volume (limit fluid intake, sodium intake, + diuresis)
4) Anticoagulation (?)
5) Pulmonary vasodilators
6) Lung transplantation
Types of pulmonary vasodilator mechanisms
1) Endothelium Receptor antagonists
2) PDE inhibitors/Guanylate cyclase stimulator (e.g. sildenafil)
3) Prostacyclin analogs
Pulmonary Venous HTN (PVH)
problem of post capillaries in lung
- due to cardiac causes (left heart) and pulmonary venous causes (problem of pulmonary vein itself, or compression of pulmonary vein)
- Can cause hydrostatic pulmonary edema
Treatment of PVH (3)
1) Decreased intravascular filling → limit fluid intake, sodium intake, + diuresis
2) Improve LV contractility → decrease LV afterload by controlling systemic HTN
3) Correct causes of LV failure (ischemia, valvular disease)
What should you NOT do when treating PVH
***DO NOT use PAH specific therapy for PVH
Will make it worse by vasodilating them because fluid will leave arteries and won’t be able to return on the venous side → pulmonary edema
The heart shadow on the AP xray is ______ than the heart shadow on the PA xray because…
larger
because the heart is further from the board (which is placed posterior to the patient)
-In PA, the xray board is anterior to the patient, and thus it is closer to the heart, making the heart silohuette much smaller
Densities as they appear on an Xray
BLACK [air → fat → soft tissue, muscle, tendon, ligaments, blood blood, water → bone calcium → metal] WHITE = radiopaque
Silhouette sign
R middle lobe or lingula infection → ?
Lower lobe infection
two structures of similar density come into contact, and the border is lost
R middle lobe or lingula infection → lose heart border
Lower lobe infection → lose diaphragm border (posterior structures)
Spine sign
typically the vertebral bodies become less, dense (more black) as you move inferiorly because there is more soft tissue as you go down.
spine sign is when there is increased opacity (more white/dense) at lower vertebral bodies indicating lower lobe pathology
Why does the trachea have a rightward course? what does this mean clinically?
Trachea has rightward course because it goes to right of aorta
Inhaled/foreign bodies more likely down right mainstem bronchus because it is wider and more vertical
What sorts of things do you look for in the pleura in an xray (3)
- Fluid → blunted costophrenic angles
- Pneumothorax → air between lung and parietal pleura surface
- Nodularity thickening or calcification
Interstitial vs. airspace/alveolar pathology in lungs appearance on xray
Interstitial = dots and dashes, linear, reticular, nodular
Alveolar = fluffy, cotton-wool like
-fluid filling airspaces
ABCDE framework to discuss chest x-ray (CXR) findings
Air: lungs including airways and pulmonary vessels
Bones
Cardiac: heart and mediastinum
Diaphragm and pleural surfaces
Everything else: lines and tubes, upper abdomen, chest wall, neck
What pushes the trachea away from midline, and what pulls the trachea away from midline?
Atelectasis = pull trachea toward it
Pleural effusion = push trachea away
Causes of acute and chronic precapillary pulmonary HTN
- Acute → thromboembolic disease, pneumonia, hypoxia (high altitude)
- Chronic → PAH, chronic thromboemboli
5 categories of causes of PAH
1) Idiopathic
2) Heritable
3) Drugs/Toxins (meth, cocaine)
4) Connective Tissue Disease
5) Portal Hypertension
Features of idiopathic PAH
- Targets pulmonary vasculature while sparing the lung parenchyma (proliferation of vascular smooth muscle)
- Primarily in younger women
- Median survival after dx only 2.5 years
Pulmonary HTN due to lung disease/hypoxia
(COPD, high altitude, emphysema)
PH associated with parenchymal or pleural disease
PH due to impaired ventilation and/or destruction of the lung
DLCO will be decreased proportionally with FEV1 and FVC
How does restrictive disease affect compliance and airway resistance
Decrease in compliance AND decrease in airway resistance
-Requires increased elastic work to distend the lung
Two causes of restrictive lung disease
increase in lung elastic recoil (stiffness) or chest wall/pleural disease
airflow and lung volumes in restrictive disease
TLC less than 80% predicted
FRC (TGV) less than 80% predicted
Suggested by symmetrically reduced FEV1 and FVC on spirometry
3 things that affect lung compliance
1) Increased thickness of lung interstitium
2) Increased lung water (pulmonary edema)
3) Increased alveolar surface tension
What causes increased thickness of lung interstitium?
Increased deposition of elastic/connective tissue
Can be in response to injury → fibroblast production of excess collagen and elastin in alveolar walls
Includes tissue lining alveolar walls → affects diffusion/gas exchange, and increases stiffness
What happens when fluid fills the interstitium (such as in pulmonary edema or pneumonia?)
fluid fills interstitium → increases elasticity → fluid fills alveoli → disrupts surfactant, increases surface tension → alveolar collapse
Acute respiratory distress syndrome (ARDS)
dysfunctional surfactant due to injury to type 2 alveolar cells
→ inflammation and injury to interstitium → decreased compliance
PFTs in restrictive disease
TLC, FRC, and RV all decreased
Flatter PV curve shifted down
Supranormal airflows because the airways are dilated due to traction applied from adjacent parenchyma = traction bronchiectasis
DLCO in restrictive disease
Decreased DLCO = impaired gas exchange
Due to decreased lung volumes causing decreased alveolar capillary SA or increased thickness of alveolar-capillary wall
- More pronounced with exercise (less time across capillary)
- DLCO is the first abnormality in patients with pulmonary fibrosis
What kinds of things can decrease chest wall compliance?
Burns, obesity, kyphoscoliosis, ankylosing spondylitis, respiratory muscly weakness, pleural fibrosis/thickening, pleural effusion
What are PFTs for restrictive disease caused by a chest wall compliance problem
1) Decreased lung volumes (FRC, RV, TLC)
2) Normal airflow
3) DLCO low due to low lung volumes, but WILL CORRECT for alveolar volume
4) **Slope of P-V curve normal but lung volumes lower
What are PFTs for restrictive disease caused by muscle weakness? How do they differ from other chest wall compliance problems?
For patients with muscle weakness: effort dependent PFTs are low, but FRC is normal
- normal airflow
- low DLCO, WILL CORRECT for alveolar volume
- slope of P-V curve normal
- reduced lung volumes
What are the classic PFTs for mixed obstructive/restrictive lung disease
decreased TLC or FRC (Restrictive)
decreased FEV1/FVC (obstructive, less than 0.70)
markedly decreased DLCO
5 categories of Interstitial Lung Disease
1) Autoimmune disease (RA, scleroderma, lupus, myositis, etc.)
2) Exposure to inorganic dusts (silica, coal dust, asbestos)
- Common in workplace
3) Exposure to organic molecules that result in hypersensitivity pneumonitis
4) Drug effect
5) Idiopathic = Idiopathic interstitial pneumonia (IIP)
Hypersensitivity Pneumonitis
Causes
Symptoms
Treatment
- E.g. mold and bird protein exposure
- Must do a detailed exposure history!
**Granulomatous reaction to inhaled organic antigens (e.g. bird poop)
Symptoms: fever, cough, SOB hours after exposure
- Resolves with removal of exposure
- Chronic exposure → interstitial fibrosis
Treatment: immunosuppression
Idiopathic Pulmonary Fibrosis (IPF)
- scarring lung disease with a pattern of injury usual of interstitial pneumonia
- Unknown etiology
- Disease of older patients (>60yrs)
- Associated with tobacco use
- Cough, DOE, fatigue
- Median survival from diagnosis is 2-3 years
Physical exam of IPF (2)
basilar predominant “velcro-crackles”, digital clubbing in advanced cases
Imaging of IPF
peripheral and basilar predominant reticulation, traction, bronchiectasis, honeycombing, and paucity of ground glass infiltrate
Pathology of IPF
spatially and temporally HETEROGENOUS fibrosis with fibroblast foci and juxtaposition of fibrotic and normal lung
Treatment of IPF
What don’t you use to treat idiopathic pulmonary fibrosis?
Pirfenidone and nintedanib (only slow progressive disease)
No response to anti-inflammatory therapy, disease of disordered alveolar repair
Sarcoidosis
Idiopathic Interstitial Pneumonia
systemic granulomatous disease of unknown etiology
**Noncaseating granulomas (collection of macrophages and epithelioid cells surrounded by lymphocytes)
- Commonly affects lungs, eyes, skin
- Presents before 40y/o
- More common and worse in African Americans
Pulmonary exam findings in sarcoidosis (5)
1) Mediastinal bilateral hilar lymphadenopathy
2) Interstitial infiltrates/nodules
3) Pulmonary fibrosis
4) Fevers, chills, fatigue
5) Cough, wheezing chest pain
Treatment of sarcoidosis
steroids and cytotoxic drugs, can resolve spontaneously
Nonspecific Interstitial Pneumonia (NSIP)
Idiopathic, collagen vascular disease related (RA, sjogren’s, scleroderma, myositis), fibrotic HP, or drug related
Young females
Better prognosis than IPF
Treatment of Nonspecific Interstitial Pneumonia
Responds to anti-inflammatory therapy
Radiography findings of Nonspecific Interstitial Pneumonia
basilar predominant reticular abnormality with volume loss, traction bronchiectasis, frequent ground glass opacity
-Rare honeycombing
pathology findings of Nonspecific Interstitial Pneumonia
temporally HOMOGENOUS fibrosis with varying degrees of inflammation and fibrosis - uniform increases in thickness of alveolar walls
Organizing pneumonia
Subacute to chronic presentation
Noninfectious pneumonia (inflammation in alveoli)
radiology findings in organizing pneumonia
ground glass and consolidation that may be migratory
pathology findings in organizing pneumonia
organizing pneumonia
Plugs of granulation tissue and fibrosis distal to bronchioles
Treatment of organizing pneumonia
Very steroid responsive but requires 6-12 months
Diagnostic strategy for ILD
Clinical-radiologic-pathologic approach
Clinical: history and physical looks for evidence of known cause of ILD (autoimmune, exposure to drugs, organic/inorganic dusts)
Radiologic: described by radiologist
Pathologic: lung biopsy
Common presentation of ILD (4)
1) Insidious dyspnea on exertion
2) Nonproductive cough
3) Restrictive PFT pattern + reduced DLCO
4) Abnormal lung imaging
*Specific diagnosis matters!
Physical exam findings common in ILD
Auscultation: end-inspiratory “velcro like” crackles
Digital clubbing in advanced cases
Joint and skin exam important in identifying coexisting (causative?) collagen vascular disease
General treatment outline for ILD
1) Remove offending exposure
2) Immunosuppressive therapy (depends on type and etiology)
3) IPF → nintedanib, pirfenidone
- Anti-inflammatory agents don’t help
4) Oxygen supplementation
5) Transplantation
Pulmonary manifestations of neurologic disease (such as ALS) (3)
1) Dysphagia (problems with pharyngeal muscle movement) → chronic aspiration of fluids and food
2) Recurrent pneumonia
3) Respiratory muscle weakness
- Inadequate ventilation
- Nocturnal hypoventilation
- Weak cough
What are the PFT patterns for neurologic diseases?
PFTs: **restrictive pattern (low FEV1, FVC but normal FEV1/FVC), reduced TLV, reduced FVC esp. in supine position
DLCO: normal initially, but prolonged hypoventilation results in atelectasis and shunt
Renal disease can be associated with what lung problem? What do the PFTs look like?
Alveolar hemorrhage
→ restrictive disease with increased DLCO (but worsening gas exchange)
Renal disease and lung disease is linked by what diseases
Vasculitis (GPA, MPA, Churg Strauss)
Goodpasture’s Syndrome
and lots of others
Inflammatory Bowel Disease pulmonary manifestations and PFT patterns
IBD –> autoimmune process can occur in lungs too!
Diverse effects:
- OBSTRUCTIVE: tracheobronchitis, subglottic stenosis, bronchiectasis, bronchiolitis
- RESTRICTIVE: pleural effusion, ILD, pulmonary embolism
PFT pattern depends on problem
Pulmonary complications associated with HIV
Infectious → bacterial pneumonia, TB, pneumocystis jirovecii, fungal pneumonia, viral pneumonia
-CD4 count is predictive
Noninfectious → Kaposi’s sarcoma, Non-Hodgkin’s Lymphoma, lung cancer, emphysema, ILD, effusions
Acute Bronchitis pathology (2)
1) neutrophils in the airway lumen and infiltrating wall of airway
2) usually infectious (bacterial)
neutrophils = multilobulated nuclei
Chronic Bronchitis pathology (3)
1) chronic inflammation (mostly LYMPHOCYTES)
2) squamous metaplasia (transformation of columnar cells to flattened polygonal squamous cells)
3) mucus gland hypertrophy (too many glands making too much mucus)
*airway attempts to protect itself from chronic inflammation
Bronchiectasis pathology (1)
1) Dilation of airway (compared to neighboring artery - should be the same size)
* consequence of chronic infections/inflammation (e.g. CF, TB, etc.)
Asthma pathology (4)
1) Thickened subbasal lamina
2) Eosinophilic inflammation (bi-lobed nucleus, red granules)
3) Mucus hyper-secretion
4) smooth muscle hypertrophy
*treated asthmatic will not have increased eosinophils (steroid sensitive)
Chronic Bronchiolitis pathology
1) Inflammation in wall of small airways that do not contain cartilage
2) Mostly infiltrating lymphocytes (chronic inflammation)
*can be reversible
Follicular bronchiolitis pathology (1)
1) Lymphoid aggregates with germinal centers (B cells in center, T cells surrounding)
* sign of long standing chronic inflammatory process (basically chronic bronchiolitis but more chronic, so more organized)
Constructive/Obliterative Bronchiolitis pathology (1)
Constrictive vs. Obliterative
CT findings?
1) Fibrosis squeezing the airway lumen shut
- Constrictive = inflammation/fibrosis between mucosa and smooth muscle squeezing lumen closed
Obliterative = airway lumen completely obliterated by fibrosis
- airway scars shut –> air trapping –> lung nonfunctional past that point
- creates mosaic air trapping due to scattered focal lesions
Granulomatous Bronchiolitis pathology (2)
1) granulomas composed of clustered histiocytes (macrophages) and multi-nucleated giant cells in airways
2) may be necrotizing or non-necrotizing
Necrotizing vs. non-necrotizing granulomatous bronchiolitis
necrotizing = infectious (neutrophils present)
Non-necrotizing = infectious, sarcoid, or chronic beryllium disease
-typically well formed and clearly delineated
Acute Pneumonia pathology (2)
1) Neutrophils, macrophages and fibrin within airspaces
2) usually infectious
* normal septae should be thin and empty, but with pneumonia, they are full of cells
Aspiration pneumonia pathology (2)
1) Airspace foreign material
2) Multi-nucleated giant cells (trying to engulf foreign stuff)
Eosinophilic pneumonia (1)
1) Eosinophils, macrophages, and fibrin within airspaces
* TX with steroids
Organizing pneumonia pathology (3)
1) myxoid fibroblastic tissue plugs small airways and airspaces
2) Usually patchy, but may be densely consolidating with entire filling of airspaces with fibroblastic tissue
3) May also include small amounts of fibrin mixed with fibroblasts
AKA BOOP and COP
Diffuse alveolar damage pathology (2)
1) Hyaline membranes (pink ribbons of fibrin) filling airspace
2) Alveolar septa thickened by inflammation and fibroblastic tissue (–> no gas exchange)
* Histologic pattern corresponds to ARDS
* most severe disease, mortality = 50%
Emphysema pathology (3)
1) enlarged airspaces
2) broken alveolar septa (irreversible damage)
3) sub-pleural blebs (can cause pneumothorax)
Smoking vs. non-smoking emphysema
Smoking = upper lobes, centrilobular (around airways)
Non-smoking (a1-antitrypsin) = lower lobes, panlobular (not worse around airways)
Respiratory Bronchiolitis (RB) (1)
smoking related disease
1) brown pigmented, “dirty” macrophages in small bronchioles and surrounding airspaces
Desquamative Interstitial Pneumonia (DIP) pathology (1)
smoking related disease
1) brown pigmented “dirty” macrophages found diffusely in airspaces, nor just around small airways
Usual Interstitial Pneumonia (UIP) pathology (3)
pathology of Idiopathic Interstitial Pneumonia
1) HETEROGENOUS fibrosis of alveolar septae
2) Fibroblastic foci present (bulging into airspace)
3) Honeycomb cystic change (end stage lung remodeling with MUCUS FILLED cysts)
- worse in lower lobes
Nonspecific Interstitial Pneumonia (NSIP) pathology (3)
1) Uniform HOMOGENOUS inflammation, fibrosis or both
2) Few fibroblastic foci
3) Honeycombing is rare
Cellular vs. Fibrotic NSIP
Uniform inflammation in septa (cellular) - REVERSIBLE
Uniform fibrosis of septa (fibrotic) - IRREVERSIBLE
Hypersensitivity Pneumonitis (HP) pathology (4)
1) Airway centered chronic inflammation (lymphocytes and histiocytes)
2) Nonnecrotizing granulomas in alveolar septae
3) Some focal organizing pneumonia (in airspaces)
4) Variable fibrosis
* Response to foreign antigens (birds, mold, hot-tub mycobacteria)
Pulmonary Hypertension pathology (3)
1) Muscular hypertrophy of pulmonary arteries
2) Muscularization of arterioles (arterioles should not have muscle)
3) Some forms may have plexiform lesions (artery lumen replaced by endothelial proliferation with numerous tangled slit-like lumens)
Thromboembolic disease pathology (2)
1) organizing fibrin clots in pulmonary arteries
2) In situ (thrombus) or travel to lung from elsewhere (embolism)
Talc embolism pathology (3)
1) polarizable crystals around vessels
2) May include foreign body giant cell
3) Usually from IV drug use
Vasculitis pathology (3)
1) Inflammation of vessel wall
2) often results in alveolar hemorrhage
3) may be autoimmune or infectious
Sarcoid/Chronic Beryllium Disease Pathology (3)
1) well-formed nonnecrotizing granulomas, often coalescing together
2) Concentric collagen deposition (hyalinization) around granulomas
3) Lymphatic distribution (near vessels, airways, and pleura)
Pulmonary Langerhans Cell Histiocytes (PLCH) pathology
cellular phase vs. fibrotic phase
Cellular phase:
- Langerhans histiocytes (CD1a, S100 positive)
- variable inflammation including eosinophils
Fibrotic phase:
-stellate scar around airway
*Usually smoking related if lung limited
Carcinoid pathology (3)
1) Nests and ribbons of neuroendocrine cells with powdery salt-and-pepper chromatin
2) Stain positive for neuroendocrine markers (chromogranin, synaptophysin, CD56)
3) Usually indolent, but may act in a malignant fashion particularly if there is nuclear atypia, high mitotic rate, or necrosis
Small Cell Carcinoma Pathology (3)
1) Small blue, easily-crushed cells with scant cytoplasm
2) Stain positive for neuroendocrine markers (chromogranin, synaptophysin, CD56)
3) High mitotic rate and abundant necrosis
Squamous cell carcinoma pathology (3)
1) Large polygonal cells with hyperchromatic (dark) nuclei and abundant cytoplasm
2) Rarely have prominent nuclei
3) May be keratinizing and form “keratin pearls”
Adenocarcinoma pathology (3)
1) Cells with large nuclei, large nucleoli, and variable amounts of cytoplasm
2) Form gland-like structures
3) If cells only line septa and do not invade, considered adenocarcinoma in situ
Large cell carcinoma pathology (1)
1) Large, sometimes bizarre-appearing malignant cells that lack the typical features of either adenocarcinoma or squamous cell carcinoma
Anatomical Boundaries of Mediastinum
sup, inf, lateral, ant, post
Superior: thoracic inlet Inferior: diaphragm Bilaterally: parietal pleura Anterior: sternum Posterior: paravertebral gutters and ribs
Anterior-Superior Compartment contains… (5)
Thymus gland Aortic root and great vessels Substernal thyroid and parathyroid tissue Lymphatic vessels and nodes Inferior aspect of trachea and esophagus
Masses in Anterior Compartment (4)
“4 Terrible T’s”
Thymic neoplasm
Teratoma (germ cell tumor)
(Terrible) Lymphoma - Hodgkin’s/non-Hodgkin’s
Thyroid neoplasm
Middle compartment contains… (7)
Pericardial sac Heart Innominate veins and SVC Trachea and major bronchi Hila Lymph nodes Phrenic, upper vagus, and recurrent laryngeal nerves
Masses in middle compartment (7)
1) *Mostly cysts (Developmental cysts, pericardial cyst, bronchogenic cyst, enteric cyst)
2) Lymphadenopathy
3) Reactive and granulomatous inflammation
4) Metastasis
5) Lymphoma
6) Vascular enlargements
7) Diaphragmatic hernia (hiatal)
Posterior compartment contains…(7)
Esophagus Descending aorta Azygous and hemiazygous veins Thoracic duct Lymph nodes Vagus nerves (lower portion) Sympathetic chains
Masses in posterior compartment (5)
*More common in children
1) Usually neurogenic in origin: Peripheral nerve (neurinomas), neurogenic tumors, sympathetic ganglia, paraganglionic tissue, meningocele
2) esophageal lesions
3) carcinoma
4) diverticuli
5) diaphragmatic hernia (Bochdalek)
Local Symptoms associated with mediastinal masses (4)
due to compression or invasion of adjacent structures
Obstruction of contiguous organs →
1) Dysphagia, hoarseness
2) SVC syndrome (facial/upper extremity swelling)
3) Cough, stridor, hemoptysis, SOB
4) Horner syndrome (sympathetic chain)
Systemic syndromes associated with mediastinal mass
Fever, anorexia, weight loss, night sweats, endocrine syndromes, autoimmune symptoms (thymus related)
Mediastinal Masses:
______% of asymptomatic masses are benign
____% of symptomatic masses are malignant
80% of asymptomatic masses are benign
50% of symptomatic masses are malignant
Adults vs. Kids with mediastinal masses
most common compartment?
Symptomatic or asymptomatic?
Adults: 65% anterior, 25% posterior, 10% middle
-Only ⅓ symptomatic
Kids: 65% posterior, 25% anterior
-⅔ symptomatic
Diagnostic evaluation of Mediastinal Masses (3)
1) Imaging (CT, CXR)
2) Labs:
- CBC with differential
- B-HCG and a-fetoprotein
- Anti-ACh receptor antibodies
3) Tissue studies (needle aspiration, or surgery - mediastinoscopy, thoracoscopy)
Complications of mediastinal masses (4)
1) Tracheal obstruction
2) SVC syndrome
3) Vascular invasion (→ hemorrhage)
4) Esophageal rupture
The Pleura
Two, single-cell thick, continuous membranes that line outer surface of lung (VISCERAL, non-innervated) and inner surface of thoracic cavity (PARIETAL, innervated)
- Meet at hilar root of lung
- Pleural space is the potential space between the two membranes
Disorders of the pleura (5)
1) Pneumothorax
2) Pleural Effusion
3) Pleural Thickening
4) Pleural Plaques
5) Pleural Tumors
Primary spontaneous pneumothorax
- no precipitating event (occurs at rest), no known lung disease
- More common in men in early 20’s, smokers and family history of PSP
- 25-54% recurrence
Tension pneumothorax
- PIP exceeds atmospheric pressure throughout expiration and often during inspiration
- Causes hemodynamic compromise by decreasing venous return and limiting CO
- Medical emergency
Signs/Symptoms of tension pneumothorax (4)
tachycardia, hypotension, cyanosis, respiratory distress
Treatment of tension pneumothorax
emergent insertion of 18 gauge angiocath in 2nd IC space along midclavicular line
DO NOT wait for confirmatory CXR
Place chest tube if pneumo confirmed
Clinical history of pneumothorax (6)
acute onset CP dyspnea cough anxiety cyanosis respiratory distress
Physical exam of pneumothorax (5 findings)
1) Hyperresonant chest percussion
2) Decreased/absent breath sounds
3) Decreased fremitus
4) Chest wall trauma
5) Decreased rib space
Treatment of pneumothorax (5)
1) observation
2) supplemental O2 (O2 leaves pleural space more easily than N2)
3) simple aspiration (release air from pleural space)
4) tube thoracostomy (chest tube)
5) Pleurodesis
Things that can mimic a pneumothorax on CXR (3)
Bullae
Skin folds
Stomach herniation
Pleural effusion clinical history (4)
dyspnea, pleuritic CP, dry cough, symptoms associated with underlying cause
Physical exam of pleural effusion (3)
1) decreased breath sounds
2) dullness to percussion
3) decreased tactile and vocal fremitus
Transudative vs. Exudative fluid composition
Transudative: results from alteration in hydrostatic forces that affect fluid formation (NON-protein rich)
-LDH low, Protein low
Exudative: due to alterations in permeability of pleura or rate of fluid removal (protein rich)
-LDH high (>0.6), protein high (>0.5)
Differential diagnosis of pleural effusion with transudative fluid (3)
hydrostatic pressure related - CHF, cirrhosis, nephrotic syndrome
Differential diagnosis of pleural effusion with exudative fluid (6)
1) Viral, bacterial, etc. infection
2) Neoplasm
3) PE
4) GI source (pancreatitis, etc.
5) Collagen vascular disease
6) Other (Asbestosis, drug-induced, iatrogenic, hemothorax, uremia)
Tumors of pleural space
Majority are malignant and metastatic
Lung, breast, lymphoma, gastrointestinal, genitourinary
Pleural Thickening
Inflammation following infection, hemorrhage, propr tx for effusion/ptx, occupational exposures (i.e. asbestos), trauma, neoplasm
Pleural Plaque
Chronic inflammation
Asbestos exposure (20-30 yrs after initial exposure)
Calcified plaques on pleura
Bupropion (Zyban, Wellbutrin)
inhibits reuptake of dopamine and NE, reducing cravings and symptoms of withdrawal
Contraindicated with seizure disorders
*Use caution with mood disorders - shown to be safe in patients with well-controlled mental illness
5 A’s of Smoking Cessation
Ask every patient about smoking at every visit
Advise every smoker, every visit to quit
Assess for readiness to quit
Assist those who are ready to quit now with brief counseling and drug therapy
Arrange follow-up, continue to ask at every visit to prevent and identify relapse
Varenicline (Chantix)
- designer drug for tobacco dependence
- Partial agonist at nicotine receptor → release of dopamine → decrease cravings and withdrawal
- Antagonist of exogenous nicotine (decreased reward from smoking)
