01a: Dyspnea, Obstructive Diseases

Question 1

Hearing “velcro” on lung sounds; formally called (X).

Answer 1

X = crackles

Question 2

(X) breath sound is normal if heard over trachea, but abnormal if heard over lungs.

Answer 2

X = bronchial

Question 3

Obstruction of airflow in bronchial tree will present as (X) breath sounds. If obstruction is in upper airway, (Y) breath sounds heard.

Answer 3

X = wheezing
Y = stridor

Question 4

T/F: PaO2 is more tightly regulated by CNS than PaCO2.

Answer 4

False - PO2 detected by peripheral chemoreceptors, while PCO2 tightly regulated by CNS

Question 5

PaO2 is determined by which three factors?

Answer 5

1. PAO2 (in alveolus)
2. Ability of O2 to diffuse into blood of lung cap
3. Ability of lung to match ventilation and perfusion (V/Q ratio)

Question 6

Write out Alveolar Gas Equation. Which factor(s) is/are measured?

Answer 6

PAO2 = FO2(PB-PH2O) - (PaCO2/R)

PaCO2 is measured

Question 7

Respiratory quotient (R) represents (X). What’s the normal value?

Answer 7

X = CO2 produced/O2 consumed

0.8

Question 8

The ABG provides (X) value(s) to allow clinician to calculate A-a gradient.

Answer 8

1. PaCO2 (to calculate PAO2)

2. PaO2

Question 9

Reduced PaO2 with normal A-a gradient are due to which potential causes? How can the clinician differentiate between these?

Answer 9

1. Hypoventilation (will produce hypercarbia)

2. Low FIO2 (high altitude)

Question 10

Shunt: you would expect SvO2 to be (increased/decreased).

Answer 10

Increased

Question 11

Four main causes of low SvO2:

Answer 11

1. Anemia
2. Low CO (delivery)
3. High VO2 (tissue consumption)
4. Arterial desaturation

Question 12

Hypoxemia is present if (X) value is (over/under) (Y).

Answer 12

1. X = PaO2 under Y = 60mmHg

2. X = oxygen sat under Y = 90%

Question 13

List the mechanistic causes of hypoxemia. Star the most common cause.

Answer 13

1. V/Q Mismatch*
2. Shunt
3. Hypoventilation
4. Diffusion abnormality

Question 14

At (X) landmark, V/Q ratio equals 1.

Answer 14

X = rib 3

Question 15

Which shunt(s) may exist in normal, healthy individual?

Answer 15

1. Thebesian veins (heart)

2. Bronchial to pulm venous anastamoses

Question 16

V/Q ratio equals zero in which disease state?

Answer 16

Shunt (V equals 0)

Question 17

V/Q ratio equals infinity in which disease state?

Answer 17

Pulmonary embolism (Q equals 0)

Question 18

Patient is hypoxemic and treatment with 100% O2 does not cause PO2 levels to rise as expected. What do you suspect is the cause of his hypoxemia?

Answer 18

R to L shunt

Question 19

Patient has thickened blood-gas barrier. Will exercise help raise his PO2?

Answer 19

No - increase in blood flow will shorten time that RBC has in pulmonary capillary, so won’t reach full O2 saturation

Question 20

Bronchial mucosa has (X) epithelium and which other cells/structures?

Answer 20

X = pseudostratified ciliated

Goblet cells, cartilage, submucosal (mucus) glands

Question 21

(X), fundamental unit of lung, consists of which structures?

Answer 21

X = acinus

1. Resp bronchiole
2. Alveolar duct
3. Alveolus

Question 22

Alveolar wall: (X) lined by endothelium rests on BM in contact with (Y), which is in contact with BM of (Z).

Answer 22

X = capillary
Y = interstitium (collagen, elastic fibers)
Z = alveolar epithelium (Type I and II pneumocytes)

Question 23

95% of alveolar surface is covered by (X) cells.

Answer 23

X = Type I pneumocytes (flattened)

Question 24

Function(s) of Type II pneumocytes.

Answer 24

1. Stem cells (replace Type I pneumocyte)

2. Surfactant production

Question 25

(X) structures in (bronchi/bronchioles/alveoli) walls allow communication.

Answer 25

X = pores of Kahn | Alveoli

Question 26

Most, (X)% of emphysema, is (pan/centri)-acinar emphysema and affects (Y) portion of acinus.

Answer 26

X = 95 Centriacinar; Y = respiratory bronchiole

Question 27

(Centri/pan)-acinar emphysema occurs in heavy smokers (often with COPD) and is more severe in (upper/lower) lobes.

Answer 27

Centriacinar; | Upper

Question 28

(Centri/pan)-acinar emphysema associated with (X) deficiency and is more common in (upper/lower) lobes.

Answer 28

Panacinar; X = alpha-1 antitrypsin Lower

Question 29

Pathogenesis of emphysema is primarily based on (X) phenomena.

Answer 29

X = protease-antiprotease and oxidant-antioxidant imbalances

Question 30

Emphysema: loss of (X) of lung parenchyma results in collapse of (Y) structures. Hence, "obstructive" disease.

Answer 30

``` X = elastic recoil Y = respiratory bronchioles ```

Question 31

Chronic bronchitis is defined clinically with which symptoms?

Answer 31

Persistent cough with sputum production (for at least 3 months in at least 2 consecutive years)

Question 32

Chronic bronchitis: which histological/structural changes would you expect to find?

Answer 32

1. Hypertrophy of submucosal glands (Reid index) 2. Goblet cell metaplasia 3. Mucus plugging 4. Fibrosis

Question 33

Reid index is the ratio of (X) to (Y). What's a normal value?

Answer 33

``` X = thickness of bronchial submucosal glands Y = thickeness of wall between epithelium and cartilage ``` 0.4

Question 34

Bronchiectasis: (reversible/irreversible) dilation of (X) structures due to (Y).

Answer 34

Irreversible; X = bronchi/bronchioles Y = destruction of wall by necrotizing infections/pneumonia

Question 35

Congenital bronchiectasis is associated with (X) disease.

Answer 35

X = CF

Question 36

Bronchiectasis typically affects (upper/lower) lobes, (uni/bi)-laterally.

Answer 36

Lower; | bilaterally

Question 37

Bacterial pneumonia presents as which patterns/distributions?

Answer 37

1. Lobar (consolidation) | 2. Bronchopneumo (patchy)

Question 38

Stages of lung inflammation in pneumonia:

Answer 38

1. Congestion 2. Red hepatization 3. Grey hepatization 4. Resolution

Question 39

In (X) stage of pneumonia inflammation, there's massive confluent exudation of RBCs, neutrophils, and fibrin in (interstitium/alveoli). Lung is red, firm, airless.

Answer 39

X = Red hepatization | Alveolar spaces

Question 40

Location of inflammation in viral/mycoplasma pneumonia is:

Answer 40

confined to alveolar septa and interstitium

Question 41

T/F: Pleuritis is more frequent in viral pneumonia than in bacterial pneumonia.

Answer 41

False

Question 42

Viral pneumonia: alveolar spaces typically contain (X).

Answer 42

X = nothing (inflammation confined to interstitium/septa) OR may have cell exudate/fibrin due to alveolar damage

Question 43

(X) pneumonia usually occurs in markedly debilitated patients. The infectious agents originate from (Y).

Answer 43

``` X = aspiration Y = oral flora (bacteria) ```

Question 44

Methacholine challenge: Increasing dose of methacholine is expected to (increase/decrease) (X) in (Y) patients. Why?

Answer 44

Decrease; X = %FEV1 (when compared to their original value) Y = asthmatic/hyperactive airway patients Methacholine increases twitchiness/bronchoconstriction of airway and asthmatics will react to lower doses of this drug

Question 45

Early phase response to inhaled allergen involves (sudden/gradual) decrease and then increase in (X) value. This is due to (Y) phenomenon.

Answer 45

Sudden; X = FEV1 Y = bronchoconstriction

Question 46

Late phase response to inhaled allergen involves (sudden/gradual) decrease and then increase in (X) value. This is due to (Y) phenomenon.

Answer 46

Gradual X = FEV1 Y = edema, secretions, inflammation

Question 47

Asthma histology: goblet cell (hypo/hyper)-plasia, (X) changes in BM, and submucosal (Y) deposition.

Answer 47

Hyperplasia; X = thickening Y = collagen

Question 48

Asthma histology: smooth muscle (hypo/hyper)-plasia and vascular (constriction/dilation).

Answer 48

Hyperplasia; | Dilation

Question 49

List the causes of airway obstruction in asthma.

Answer 49

1. Bronchial/bronchiolar mucosal inflammation and edema 2. Smooth muscle hypertrophy/constriction 3. Excess mucous in lumen

Question 50

Early day care exposure and older siblings are factors that favor Th(1/2) phenotype, aka (X).

Answer 50

Th1; | X = protective immunity

Question 51

Widespread use of antibiotics and urban environments are factors that favor Th(1/2) phenotype, aka (X).

Answer 51

Th2; | X = allergic diseases (i.e. asthma)

Question 52

Asthma: (increase/decrease) in AP diameter and (increase/decrease) in accessory muscle use.

Answer 52

Increase both

Question 53

Which skin findings might you look for when suspecting asthma in patient?

Answer 53

Eczema

Question 54

Which upper airway findings would you look for when suspecting asthma in patient?

Answer 54

1. Sinusitis 2. Rhinitis 3. Nasal polyps

Question 55

T/F: In most cases of asthma, chest X-ray is normal.

Answer 55

True

Question 56

List the primarily therapies for acute asthma exacerbation.

Answer 56

1. Beta-2 agonist administration (repetitive, rapid-acting) 2. Glucocorticosteroids (systemic) 3. Oxygen supplementation