Respiratory Pathology Flashcards

1
Q

asthma dx

A
clinical:
*episodic
*wheezing
SOB (potentially hard to talk, accessory muscle use --> EMERGENCY)
cough
mucus
chest tightness/chest pain

may use sx journals to identify causes of exacerbations

further testing rarely done, but if it were:

  • spirometry: only abnormal during exacerbation, reduced FEV1 (FEV1/FVC <70%)
  • peak flow: PEV (peak expiratory volume) and PEFR (peak expiratory flow rate) both reduced
  • bronchoprovocation studies show sx exacerbation with certain irritants
  • FeNO (fractional exhaled nitric oxide) elevated (note that this is more often used to monitor tx response)
  • sputum analysis: curschmann’s spirals (casts from small bronchi that cause mucus plugs, may obstruct to extent that no air or meds can pass), charcot-leydan crystals (needle-shaped shards from eosinophil breakdown)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

FeNO

A

fractional exhaled nitric oxide
NO is a marker of inflammation
i.e., indicates airway inflammation

most often used in measuring tx response to asthma
sometimes for dx asthma

elevated in asthma, especially during exacerbation
elevated in COPD exacerbation only
normal to low in stable or chronic COPD

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

extrinsic vs intrinsic asthma

A

extrinsic (allergic):
allergen –> DC –> Th2 –> eosinophil recruitment
– IL4 antagonists will be more effective in this population

intrinsic (nonallergic):
irritant/stimulus/hormonal signalling –> mast cells –> neutrophils and eosinophils
– leukotriene antagonists will be more effective in this population

  • both involve both pathways, but skewed significantly toward one or the other
  • both result in eosinophil activation
  • both result in bronchospasm, bronchial edema, and bronchial hyperreactivity
  • both treated with beta-adrenergic agonists (albuterol; bronchodilator) and steroids (fluticasone, budensonide; broad-spectrum anti-inflammatory)
  • both can be treated with TSLP antagonists and eosinophil antagonists: IL5, IL13, IgE (antagonists)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

episodic wheezing and dyspnea with “seasonal allergies”

A

extrinsic asthma

tx bronchodilators, steroids, potentially IL4 and TSLP antagonists, IL5, IL13, IgE antagonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

episodic wheezing and dyspnea “but only when I exercise”

A

intrinsic asthma
tx bronchodilators, steroids, potentially leukotriene and TSLP antagonists, IL5, IL13, IgE antagonists

r/o deconditioning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

episodic wheezing and dyspnea d/t “smoke from the wildfires”

A

intrinsic asthma

tx bronchodilators, steroids, potentially leukotriene and TSLP antagonists, IL5, IL13, IgE antagonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

episodic wheezing and dyspnea d/t “smog”

A

intrinsic asthma

tx bronchodilators, steroids, potentially leukotriene and TSLP antagonists, IL5, IL13, IgE antagonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

episodic wheezing and dyspnea d/t “hay fever”

A

extrinsic asthma

tx bronchodilators, steroids, potentially IL4 and TSLP antagonists, IL5, IL13, IgE antagonists

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

episodic wheezing and dyspnea d/t “stress”

A

intrinsic asthma
tx bronchodilators, steroids, potentially leukotriene and TSLP antagonists, IL5, IL13, IgE antagonists

r/o anxiety/panic attacks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

asthma complications

A

short term: asthma attacks –> life threatening

long term –> chronic infections, fibrosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

curschmann’s spirals

A

casts from small bronchi that cause mucus plugs, may obstruct to extent that no air or meds can pass

seen in asthma sputum analysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Charcot-laydan crystals

A

needle-shaped shards from eosinophil breakdown

seen in asthma sputum analysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

asthma severity classification

A

intermittent, mild persistent, moderate persistent, severe persistent

consider:

  • sx frequency
  • sx timing (early morning, late night)
  • frequency of rescue inhaler use
  • FEV1, PEV, PEFR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

potential asthma triggers

A

extrinsic/allergic:

  • seasonal, pollen, hay fever, etc
  • dust, dust mites
  • mold
  • cockroaches
  • pets
  • etc.

intrinsic/nonallergic:

  • tobacco and other inhaled drugs
  • viral infections
  • environmental smoke
  • smog, car fumes
  • exercise
  • stress

either/drug-induced:

  • beta blockers
  • NSAIDs (especially aspirin/COX1)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

preferred asthma treatment track (GINA 2021 track 1)

A

step 0: identify and eliminate triggers, where possible

step 1-2: sx < 4-5 days/wk
- ICS-formoterol as needed

step 3: sx most days or waking 1+ night/wk, or uncontrolled on step 1-2

  • low-dose maintenance ICS-LABA
  • ICS-formoterol as needed

step 4: sx every day or waking 1+ night/wk, AND low lung function, or uncontrolled on step 3

  • medium-dose maintenance ICS-LABA
  • ICS-formoterol as needed
  • short-course oral corticosteroids during severe attacks or persistent phases

step 5: sx daily, waking 1+ night/wk, and low lung function, or uncontrolled on step 4

  • all of step 4 PLUS:
  • LAMA
  • refer for phenotypic assessment, based on results:
  • – anti-IgE
  • – anti-IL5/5R
  • – anti-IL4R
  • consider high-dose ICS-LABA
  • ICS: inhaled corticosteroid, e.g. fluticasone, budesonide
  • LABA (should not be used w/o ICS): long-acting beta AGonist, e.g. albuterol SULFATE, formoterol, salmetrol
  • ICS-LABA: combined formulations e.g. budenoside-formoterol (Symbicort), fluticasone-salmeterol (Advair)
  • note that formoterol onset is fast enough to be used as a rescue inhaler; LABAs otherwise must me combined with a SABA rescue inhaler
  • LAMA: long-acting muscarinic ANTagonist, e.g. tiotropium bromide; may be used in place of LABA if other LABAs cannot be used
  • SABA: short-acting beta AGonist, e.g. albuterol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

pt with asthma less than 4-5 days a week should be started on ____

A

ICS-formoterol (preferred) prn
or
(< 2x/month) SABA (e.g., albuterol) + ICS whenever albuterol is needed
(> 2x/month) low-dose maintenance ICS + prn SABA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

pt with asthma most days, waking 1+ night/wk, or uncontrolled on prn-only should be started on ____

A

ICS-formoterol low dose daily and prn (preferred)

or low-dose maintenance ICS and prn SABA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

pt with asthma daily, waking 1+ night/wk, and reduced lung function, or uncontrolled on low-dose + prn should be started on ____

A

ICS-formoterol med-dose daily and prn (preferred)
or medium-dose maintenance ICS-LABA and prn SABA

and oral corticosteroids in severe attacks or persistent phases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

pt with asthma daily, waking 1+ night/wk, and reduced lung function, or uncontrolled on med-dose + prn should be started on ___

A

med to high dose ICS-formoterol (preferred; or ICS-LABA + prn SABA)
+ LAMA
+ refer for phenotyping (–> IgE, IL4, IL5, etc. biologics based on results)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

indications for LABA vs SABA

A

COST: $30-40 without insurance for SABA + ICS only versus $200-300 without insurance for ICS-formoterol, both with coupon

AGE: ICS-formoterol is approved as first-line for ages 12+ or second-line for ages 6+, i.e., children <6 must use SABA + ICS, and children 6-12 must use SABA + ICS as first-line tx

CONTRAINDICATIONS: ICS-formoterol is contraindicated in diabetes, htn, heart problems, liver problems, hypO-K, immunocompromised, certain infections, and others; albuterol alone is safe in many of these conditions, adding ICS makes it more difficult. Albuterol hypersensitivity is more common.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

asthma pt talking in phrases, prefers sitting, not agitated, no accessory muscle use, rr 20-30, hr 100-120, O2 sat 90-95

A

mild to moderate exacerbation

tx:

  • SABA 4-10 puffs via spacer + metered dose inhaler
  • oral corticosteroids (prednisolone) 40-50 mg or 1-2 mg/kg up to 40 mg in children
  • oxygen, nasal canula OK in adults, mask in children

transfer to acute care if worsening
else assess response at 1 hour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

d/c and f/u after asthma exacerbation

A

d/c if O2 sat >94, not using SABA, PEF improving

on d/c start or step up ICS, continue reliever, check adherence and technique, OCS for 5-7 days (adults) or 3-5 days (children)

f/u at 1-2 days (children), 2-7 days (adult)
cont OCS if needed for 1 wk up to 3 mo, check modifiable risk factors, check inhaler adherence and technique

refer to pulm if >1-2 exacerbations/year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

asthma pt drowsy or confused, silent chest

A

LIFE THREATENING
transfer to acute care

m/w and at ED, high-dose SABA via nebulizer, ipratropium bromide, O2, systemic corticosteroid, HF-NRB O2
consider Mg++ IV

rescue breathing if unresponsive
intubate as soon as feasible, ideally prior to respiratory arrest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

asthma pt talking in words only, tripoding or hunched, accessory muscle use, rr >30, hr >120, O2 sat <90%, PEV <50% of pt’s best

A

severe attack
transfer to acute care

m/w and at ED, med-to-high dose SABA via nebulizer, ipratropium bromide, O2, systemic corticosteroid, HF-NRB O2
consider Mg++ IV

monitor for signs of life-threatening attack or arrest:
increase doses
rescue breathing if unresponsive
intubate as soon as feasible, ideally prior to respiratory arrest

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

emphysema pathophysiology

A
  • irritants activate neutrophil elastases, lead to progressive breakdown of elastin in bronchiolar walls
  • becomes more compliant and loses recoil (becomes less like a balloon and more like a plastic bag)
  • air becomes trapped in alveoli, leading alveoli to “burst”
  • burst alveoli can’t hold air, and “mega alveoli” created from multiple alveoli bursting and fusing together have less surface area to exchange gas
  • can lead to increased inflammation and fibrosis over time
  • often accompanies chronic bronchitis as both are caused by similar irritants
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

emphysema dx

A
clinical:
SOB esp w/ exertion
tachypnea
*hypOcapnic
*pursed lip breathing + red cheeks + lack of cyanosis = "pink puffers"
*barrel chest
minimal cough w/ small amounts of mucus, unless +chronic bronchitis
reduced breath sounds
hypER-resonant

spirometry req’d for dx:

  • FEV1, FVC, and FEV1/FVC ratio all decreased (FEV1 decreases more than FVC)
  • because harder to expel air
  • progressive worsening over time

imaging: CT preferred, XR also can see many changes
*hyperinflation, flattened hemidiaphragms
increased, irregular radiolucency (more white)
— most common type, centrolobular (termed based on the part of the alveolus it affects) is primarily seen in the upper part of all lobes, patchy distribution
— panlobular (again, named based on effect on alveolus) is associated with alpha-1-antitrypsin deficiency and affects lower lobes
diaphragmatic tenting
fewer blood vessels, distorted

note that emphysema dx is based mostly on structural changes while chronic bronchitis dx is based mostly on clinical presentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

copd and heart failure

A
  • lungs have natural response to vasoconstrict to damaged or blocked alveoli, to shunt to functioning alveoli
  • too many damaged or blocked alveoli –> too much vasoconstriction (pulmonary hypertension)
  • increased afterload to right ventricle –> RVHF
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

alpha-1-antitrypsin deficiency

A

an inherited form of emphysema d/t lack of enzyme that breaks down proteases that break down elastin (overall result is elastin breakdown)

clinical suggestions:

  • usually onset b/f age 30
  • little to no exposure history
  • familial
  • distribution in lower lobes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

main causes of emphysema

A
*cigarette smoke (1st or 2nd hand)
indoor open-flame/coal stoves (developing countries)
environmental/smog
occupational (asbestos, coal, ...)
genetic (alpha-1-antitrypsin deficiency)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

ventilation-perfusion mismatching

A

lot of air
not a lot of gas exchange
happens in emphysema due to air trapping that results in breakdown of alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

chronic bronchitis pathophysiology

A
  • inflammation of bronchial walls (neutrophils and lymphocytes)
  • smooth muscle cell proliferation and reactivity –> bronchospasms, cough, wheezing
  • goblet cell proliferation and hypertrophy –> too much mucus (blocks airways)
  • squamous metaplasia (structural changes) –> cilia not as effective at clearing mucus –> too much mucus (blocks airways)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

chronic bronchitis dx

A
clinical
*persistent productive cough (3+ mo/yr x 2+ yr)
SOB esp w/ exertion in later stages
tachypnea
*wheezing + crackles/rales
*hypERcapnic
hypoxia
*cyanosis = "blue bloaters"
reduced breath sounds
hypER-resonant

r/o other causes of chronic cough

spirometry req’d for dx:

  • FEV1, FVC, and FEV1/FVC ratio all low (FEV1 decreases more than FVC) - same as emphysema
  • because harder to expel air
  • worsens over time
  • same as emphysema

imaging: not always done
- larger, more defined bronchi(oles) (“circled” due to thickening of bronchi)
- bronchi(oles) may be blocked by mucus
- concomitant emphysema and/or fibrosis may be observed

note that emphysema dx is based on structural changes while chronic bronchitis is a clinical dx

33
Q

complications of chronic bronchitis

A
  • increased susceptibility to lung infections (mucus plugs trap bacteria in and make it harder to expel them via mucus)
  • RVHF (d/t pulmonary htn d/t reactive vasoconstriction)
34
Q

copd maintenance tx (general principles)

A
  • reduce modifiable risk factors (smoking, occupational exposures)
  • beta-adrenergic agonists (albuterol, LABAs)
  • LAMAs
  • sometimes ICS
  • oxygen, at-home may be needed
  • treat complications
35
Q

bronchiectasis

A

airway dilation
— associated mucosa thinning can lead to exposed capillaries and hemoptysis

causes:

  • chronic/repetitive injury, such as infections
  • TB most common cause
  • autoimmune disease or impaired host response
  • CF
  • primary ciliary dyskinesia

tx:

  • airway clearance regiments
  • sometimes bronchodilators and ICS
36
Q

hemoptysis

A

coughing up blood

usually related to bronchiectasis, which exposes capillaries d/t mucosa thinning

37
Q

PFTs in asthma vs copd vs restrictive diseases (e.g. fibrosis)

A

COPD:

  • FEV1 decreases
  • FVC may also be decreased in severe disease, but less (actual lung damage causing reduction in ability for air to flow out)
  • low FEV1/FVC ratio
    • FEV1/FVC ratio does not improve (<12%) with administration of bronchodilators

Asthma

  • also an obstructive disease, so similar to COPD
  • FEV1 decreases
  • FVC normal to near-normal (can still blow out the same amount of air because there’s nothing wrong with their lungs, just takes longer b/c of airway obstruction)
  • low FEV1/FVC
  • only low during exacerbation or uncontrolled disease
    • FEV1/FVC improves >12% with administration of bronchodilators

Restrictive disease

  • preserved FEV1/FVC ratio (ability to expel air is fine)
  • – BUT both FEV1 and FVC are lower because absolute volumes are smaller (d/t reduced TLC)
  • – this is why ratio is more important than FEV1 or FVC alone
  • – no change with bronchodilators
  • reduced TLC d/t inhalation difficulty, reduced space in lungs (d/t all the fibrosis)

FEV1: forced expiratory volume in one second
FVC: forced vital capacity (expiratory volume during an entire breath)
TLC: total lung capacity

38
Q

COPD treatment (based on GOLD classifications)

A

*in all groups reduction of risk factors e.g. smoking is most important

Group A: 0-1 exacerbations not requiring hospitalization w/in year AND CAT <10
- SABA only

Group B: 0-1 exacerbations not requiring hospitalization w/in year and CAT ≥10
- LABA or LAMA

Group C: ≥2 exacerbations or ≥1 requiring hospitalization w/in year AND CAT <10
- LAMA

Group D1: ≥2 exacerbations or ≥1 requiring hospitalization w/in year and CAT 10-20
- LAMA ± LABA

Group D2: ≥2 exacerbations or ≥1 requiring hospitalization w/in year and CAT ≥20
- LAMA + LABA

Group D3: ≥2 exacerbations or ≥1 requiring hospitalizations w/in year and CAT ≥20 and eosinophils ≥300
- ICS-LABA ± LAMA

  • SABA: short-acting beta AGonist, e.g. albuterol
  • LAMA: long-acting muscarinic ANTagonist, e.g. tiotropium bromide; may be used in place of LABA if other LABAs cannot be used
  • ICS-LABA: combined formulations e.g. budenoside-formoterol (Symbicort), fluticasone-salmeterol (Advair)
  • note that formoterol onset is fast enough to be used as a rescue inhaler; LABAs otherwise must me combined with a SABA rescue inhaler
  • ICS: inhaled corticosteroid, e.g. fluticasone, budesonide
  • LABA (should not be used w/o ICS): long-acting beta AGonist, e.g. albuterol SULFATE, formoterol, salmetrol
39
Q

management of COPD exacerbations

A

initial:

  • SABA (albuterol) via nebulizer ± short-acting inhaled anticholinergic (ipatropium)
  • O2 via nasal canula or if severe HF-NRB
  • if very severe give CPAP or BiPAP; intubation is last resort

f/u:

  • most commonly d/t respiratory infections: give antibiotics if bacterial suspected (common)
  • 5-7 days of systemic corticosteroids
  • switch to LABA or LAMA if not done already, consider increasing dose
40
Q

forms of asbestos related lung diseases

A

asbestos plaques - benign collagen deposits (least severe)
asbestosis - pulm parenchymal fibrosis
bronchogenic carcinoma - esp in smokers
malignant mesothelioma - rare, pleura or peritoneum, presents with large pleural effusion (most severe)

41
Q

asbestos plaques defn

A

benign collagen deposits in parietal pleura

least severe of asbestos-related pathologies

42
Q

asbestosis defn

A

pulmonary parenchymal fibrosis secondary to asbestos exposure

43
Q

bronchogenic carcinoma defn

A

carcinoma of bronchi

40-60x increased in dual asbestos–tobacco exposure

44
Q

malignant mesothelioma defn

A

malignancy of pleura or peritoneum
presents with large pleural effusion
rare, asbestos related
not affected by smoking

45
Q

jobs associated with asbestos exposure

A
  • mining
  • milling
  • fabrication
  • building fireproofing, maintenance, demolition, installation, thermal insulation
  • shipbuilding, repair, refitting (esp seen in WWII vets)
  • brake work
  • plumbers, electricians, welders
  • geologists, archeologists, bricklayers, sculptors, others working with many types of rock
46
Q

asbestos is ___(fibrogenic/low-fibrogenic) in the ___(class)

A

fibrogenic silicate mineral

cheap, easy to mine “magic mineral”

47
Q

occupational asthma with latency pathophys

A

allergic sensitization over time to any workplace chemical, for example:

    • health care workers and latex
    • isocyanate in auto spray paints, plastic or rubber manufacturing
    • carpenters and wood dust

after sensitization, even very low dose can cause asthma attack

48
Q

occupational asthma without latency

previously reactive airways dysfunction syndrome/RADS

A
  • single exposure to highly toxic material
  • – e.g., paper mill explosions (SO2), chlorine, mustard gas (bleach + HCl)
  • sx w/in 24 h
  • can be acutely fatal w/o tx
  • tx w/ oral + inhaled corticosteroids
  • may not improve with time

PREVENTION: respirators, occupational controls

49
Q

low-fibrogenic, granulomatous occupational irritant(s)

A

beryllium

50
Q

low-fibrogenic, depositional occupational irritant(s)

A
iron
tin
barium
titanium
glass
wool
51
Q

silicate(s) affecting lower airways

A

asbestos

52
Q

silicate(s) affecting upper airways

A

talc

  • after significant cancer risk was observed in miners, strong market push toward non-talcum powders
  • talcum powders in standard usage are less likely to cause any problems but are definitely not recommended in babies, everyone else maybe steer clear jic
  • unclear evidence on frequent use of talcum for feminine hygiene and cervical cancer

kaolin

  • found as a filler in many medications, is safe in normally ingested amounts
  • dangerous in frequent inhalation of large doses, e.g. mining, milling, lab synthesis
53
Q

fibrogenic airway irritants

A
silica/silicon dioxide
silicates
- asbestos
- talc
- kaolin
coal dust
aluminium
54
Q

examples of diffuse parenchymal lung diseases

A

pneumoconiosis

  • coughing
  • inflammation, fibrosis
  • dust inhalation
  • occupational

hypersensitivity pneumonitis

  • type iii hypersensitivity
  • microorganisms, plants and animal proteins, chemicals
  • inflammation, fibrosis

drug-induced lung disease

  • typically rare adverse event of many drugs
  • nitrofurantoin, Amiodarone, methotrexate are among top offenders
  • often identified late in development or post-marketing

vasculitis

connective tissue disease including RA, SLE, systemic sclerosis, polymyositis

idiopathic interstitial pneumonia (IIP), e.g.

  • idiopathic pulmonary fibrosis (IPF)
  • cryptogenic organizing pneumonia (COP)
  • acute interstitial pneumonitis (AIP)
  • others

Others: sarcoidosis, eosinophilic pneumonia, pulmonary langerhans cell histiocytosis, etc.

55
Q

pneumoconiosis

A
  • diffuse parenchymal lung disease
  • coughing
  • inflammation, fibrosis
  • dust inhalation
  • occupational
56
Q

hypersensitivity pneumonitis

A
  • diffuse parenchymal lung disease
  • type iii hypersensitivity
  • microorganisms, plants and animal proteins, chemicals
  • inflammation, fibrosis
57
Q

drug-induced lung disease

A
  • diffuse parenchymal lung disease
  • typically rare adverse event of many drugs
  • nitrofurantoin, Amiodarone, methotrexate among top offenders
  • often identified late in development or post-marketing
58
Q

bronchiolitis obliterans

A
  • bronchiole obstruction due to inflammation (an airway disease)
  • “popcorn lung” based diacytel in popcorn butter
  • dry cough, SOB, wheezing, fatigue
  • worsen weeks to months
  • can be occupational d/t chemical exposure, e.g.
  • – nylon flocking
  • – polyamide-amine dyes used in textile prints
  • – thionyl chloride in battery manufacture
  • – diacetyl flavorings manufacture
  • can also be non-occupational, e.g.
  • – connective tissue disorders including RA, SLE, systemic sclerosis, polymyositis
  • – bone marrow or heart-lung transplant
  • – certain respiratory infections
59
Q

common findings among diffuse parenchymal lung diseases

A

sx:

  • generally chronic, often dry cough; subacute, acute also possible; acute on chronic common
  • SOB
  • tachypnea
  • nail deformities
  • weight loss
  • exercise intolerance

dx:
restriction on PFTs
low DLCO
ground-glass opacities, micronodules, consolidation, UIP pattern

(UIP pattern = lower lobe honeycombing, reticular opacities, ground glass opacities, traction bronchiectasis)

60
Q

idiopathic pulmonary fibrosis (IPF)

A
  • diffuse parenchymal lung disease
  • idiopathic interstitial pneumonia (IIP)

sx:

  • cough, usually insidious onset
  • SOB
  • other DPLD sx
  • r/o toxic exposure

pe:

  • inspiratory crackles
  • r/o rheum: rash, synovitis (joint swelling)

dx:

  • radiographic UIP pattern
  • labs normal
  • –r/o rheum (CRP, ANCA, ANA)
  • surgical biopsy is gold standard but not common

risk:

  • age >60
  • smoking
  • familial

tx:

  • limited, both drugs slow but don’t halt progression, don’t improve lung function, difficult to tolerate
  • pirfenidone - unknown mechanism
  • Nintedanib - multi-TYRK inhibitor (anti-fibrotic)
  • among most common indications for lung transplant

(UIP pattern = lower lobe honeycombing, reticular opacities, ground glass opacities, traction bronchiectasis)

61
Q

UIP pattern

A

lower lobe honeycombing
reticular opacities
ground glass opacities
traction bronchiectasis

seen in diffuse parenchymal lung diseases, especially idiopathic pulmonary fibrosis (IPF)

62
Q

resting VO2, VCO2, and respiratory exchange ratio (R) in healthy adult

A

VO2 ~250 ml/min
VCO2 ~200 ml/min

R = VCO2 / VO2 = 200/250 = 0.8

63
Q
define:
VO2, VCO2
respiratory exchange ratio (R)
V•(sub)E
V(sub)T
f(sub)R
V(sub)D(anat)
V(sub)A
V•(sub)A
V(sub)D(alv)
V(sub)D(physiol)
A

VO2 & VCO2 = resting rate of O2 or CO2 consumption in ml/min

R = VCO2 / VO2

V•E = minute ventilation (minute volume) in L/min = total volume expired in one minute = VT * fR
• over V indicates that it is the volume per minute

VT = tidal volume = expired breath volume per breath

fR = respiratory rate (frequency) = breaths per minute

VD(anat) = anatomical dead space = amount of air in L that remains in conducting airways and does not reach alveoli

VA = volume reaching alveoli per breath = VT - VD

V•A = V•E - V•D (anat)

VD(alv) = alveolar dead space = volume of air distributed to non-functional alveoli

VD(physiol) = physiological or effective dead space = VD(anat) + VD(alv)

64
Q

minute ventilation, anatomical dead space volume and V•(sub)A in healthy adult

A

V•E (minute ventilation) ~ 8 L/min
VD(anat) (anatomical dead space) ~ 150 ml

at fR of 10 breaths/min:
V•A = V•E - (VD * fR) = 8 L/min - (0.150 L/breath * 10 breaths/min) = 6.5 L

65
Q

what would happen to volume reaching alveoli in:

  • tachypnea
  • emphysema
  • restrictive lung disease
A

V•A = V•E - (VD * fR)

tachypnea increases fR –> decreased V•A

emphysema increases VD d/t air trapping –> decreased V•A

restrictive lung disease decreases minute ventilation (volume exhaled per minute) = V•E –> decreased V•A

with many diseases a combination of factors will be affected and all should be taken into account to estimate or directly measure V•A

66
Q

define

  • PACO2 and PAO2. How do their typical levels compare to atmospheric air?
  • F(sub)AO2 and FACO2
  • F(sub)IO2 and FICO2
  • V•CO2
A

A = alveolar
I = inspired/atmospheric
P = partial pressure
F = fraction
O2 lower than normal air as it is moved into the capillaries
CO2 higher than atmospheric air as it is moved into the alveolus

V•CO2 = amount exhaled - amount inhaled = (volume exhaled * FACO2) - (volume inhaled * FICO2)

FICO2 ~ 1, so FACO2 ~ V•CO2 / VA
VA = VT - VD(physio)

67
Q

hyperpnea vs hyperventilation vs tachypnea

A

hyperpnea = any increase in ventilation (more air into lungs), including hyperventilation and metabolic hyperpnea (such as when exercising)

hyperventilation = increased ventilation (volume into lungs) without increased V•CO2, i.e., is not related to metabolic demand –> low arterial PCO2

tachypnea = fast breathing; also typically shallow so may not result in hyperpnea

68
Q

NCSLC tx

A

often surgical

sgx yes: localized

sgx maybe:
- ipsilateral LN involvement

sgx no, radiation + chemo yes:

  • contralateral or supraclavicular LN involvement
  • invasion through chest wall or mediastinum
  • metastasis
  • other c/i such as age, frailty, etc

sgx approach:

  • usually lobectomy
  • more conservative resections considered if low lung reserve but success rate lower
  • total pneumonectomy may be needed e.g. in hilum involvement
  • usually open thoracotomy
  • video assisted and robotic b//c more common

b/f surgery:

  • lymph node eval mediastinoscopy or endobronchoscopic US + fine needle aspiration
  • possible neoadjuvant immunotx, chemotx, and/or radiation

post-sgx:

  • adjuvant tx not always needed or done
  • immunotherapy fairly common
  • platinum chemo b//c less common
69
Q

metastasis or refractory disease and its tx in lung cx (NSCLC or SCLC)

A

common sites:

  • brain (esp in SCLC but also common in NSCLC)
  • bone

standard tx:

1) chemo + radiation or chemo then radiation
2) immunotx

radiation:

  • common
  • whole brain sometimes done (in brain metastasis) but has many side fx such as memory loss
  • localized ideal, relatively low morbidity

chemo:

  • usually platinum-based (cytotoxic)
  • pemetrexed (anti-metabolite) common in non-squamous, not effected in squamous

targeted:

  • VEGFi in NSCLC, caution in squamous d/t hemorrhage risk
  • Ab-drug conj more common
  • EGFRi recently approved

immunotx:
- anti–PD-1/PD-L1

70
Q

most common driver mx in NCSLC

A

EGFR

71
Q

SCLC

A
  • ~15% of cases
  • ~99% d/t smoking
  • most responsive to initial chemo
  • sgx removal only possible in ~2% of cases
  • relapse almost always occurs
  • in local metastasis, usually chemo + radiation
    • invasion thru mediastinum or pleura, or
    • contralateral LN involvement
  • in advanced metastasis, usually immunotx + chemo
  • in recurrent disease, few to no effective tx
72
Q

types of lung cx

A
  • SCLC (~15%)
  • NCSLC (~85%)
    • squamous cell carcinoma:
  • — adenocarcinoma (most common)
  • — large cell carcinoma
    • non-squamous cell carcinoma
73
Q

key pathways targeted in pulmonary arterial hypertension (PAH)

A

big picture:

  • correcting endothelial dysfunction
  • vasodilation
  • endothelin-1 blockade
    • ambrisentan
    • bosentan
    • macitentan
  • PGI2 (prostacyclin) AGonist
    • epoprostnol
    • treprostinil
    • iloprost
    • selexipag
  • nitric oxide AGonist
    • sildenafil
    • tadalafil
    • riosiguat
74
Q

PAH clinical signs

A
  • pulmonary vascular remodeling
  • plexiform lesions
  • exertional SOB
  • syncope
  • elevated JVP
  • LE edema
  • right HF, dilation, remodeling

possible (depending on cause):

  • connective tissue disease/AI
  • HIV
  • liver disease
  • substance use (esp meth)
  • toxic exposures
  • family hx

precapillary PH w/ mPAP >20, PAWP <15, PVR >3

75
Q

some causes/types of pulmonary hypertension:

A

PAH:

  • idiopathic
  • heritable
  • drug and toxin
  • connective tissue disease/autoimmune
  • HIV
  • portal (liver) hypertension
  • congenital heart disease
  • schistomiasis
  • calcium-channel blockers (long term)
  • persistent PH of newborn

other PH:

  • left HF
  • restrictive and/or obstructive lung disease
  • hypoxia ± lung disease
  • thrombus/embolus
  • more rarely:
    • heme
    • metabolic
    • chronic renal failure
76
Q

type I vs type II respiratory failure

A

type I = hypoxemic
PaO2 < 60 mmHg despite supplemental O2

type II = hypercapnic/ventilatory
PaCO2 > 50 mmHg

77
Q

causes of hypoxemic failure

A

widened A-a gradient:

  • ventilation/perfusion (V/Q) mismatch
    • dead space = V w/o Q; V/Q –> ∞
    • shunt = Q w/o V; V/Q = 0, e.g.
  • — ASDs, VSDs (septal defects)
  • diffusion impairment
    • barrier e.g. edema, fibrosis
    • surface area = emphysema, pneumonectomy
    • decreased O2–Hgb association e.g. CO poisoning, anemia

normal A-a gradient:

  • low fractional inspiration of O2 (FiO2)
    • e.g. high altitude, enclosed spaces
  • mixed type I/type II failure: hypoventilation
    • can’t breathe in enough O2
    • can’t breathe out enough CO2
  • multifactoral
78
Q

A-a gradient

A

alveolar–arterial gradient

difference between alveolar and atmospheric O2 (PAO2 - PaO2)

due to physiologic shunts and dead space, not all atmospheric O2 reaches alveoli

normal A-a gradient = (age + 10)/4

79
Q

diagnosing respiratory failure

A

clinical algorithm/flowchart:

  1. PaO2 (arterial O2) is low
  2. Calculate A-a gradient (PAO2 - PaO2) and normal A-a gradient (age + 10) / 4

3a. if normal, is hypoventilation or low FiO2.
- – is there enough oxygen in the air? if yes, hypoventilation. if no, low FiO2.

3b. if A-a is increased, give 100% O2.
3b. 1. If PaO2 increases, it is V/Q mismatch or diffusion impairment.
3b. 2. If PaO2 does not increase, it is shunting.