copd

Question 1

what are the most common symptoms of copd?

Answer 1

dyspnea, cough (early morning), sputum production

Question 2

outline the mechanism of copd

Answer 2

exposure to smoke and environmental particles + host factor amplifying mechanisms causes lung inflammtion
this leads to oxidative stress, which can be inhibited by antioxidants and antiproteases. repair mechanisms are impaired by oxidative stress.
alveolar wall is destroyed, mucus is hypersecreted and fibroblasts cause abnormal tissue repair

Question 3

why do the airways narrow in bronchitis?

Answer 3

remodelling

Question 4

which airways narrow first in bronchitis?

Answer 4

smaller airways in periphery - have no cartilage to keep them open

Question 5

which enzyme causes alveoli to lose elastic tissue?

Answer 5

proteolytic enzymes destroy elsatin and collagen

Question 6

which inflammatory cells and mediators are involved in copd?

Answer 6

neutrophils
macrophages
t cells (more cd8 than cd4)
leucotriene B4 - attracts neutrophils and t cells
IL-8 and growth related oncogene alpha - amplifies pro inflammatory responses
TNF alpha, IL - 1 beta, IL-6 - proinflammatory
TGF beta - causes fibrosis

Question 7

what pathological changes occur in the airway bronchial submucosal glands?

Answer 7

hypertrophy and hyperplasia

Question 8

do goblet cell numbers increase or decrease?

Answer 8

increase

Question 9

destruction of what cell causes difficulty expectorating?

Answer 9

cilia cells

Question 10

expiratory flow limitation is caused by…

Answer 10

decreased elastic recoil of lungs
decreased gas exchange
hyperinflation
sputum production

Question 11

what causes the wheeze in copd?

Answer 11

stenosis of bronchial tree - decreased diameter

Question 12

what are some other clinical findings of copd?

Answer 12

increased respiratory rate
accessory muscle use
wheeze
reduced chest expansion
barrel chest
reduced breath sounds
asterixis (liver hand flap)
cyanosis
cor pulmonale

Question 13

what are some non respiratory related features of copd?

Answer 13

weight loss
muscle wasting
cardiovascular comorbidities
depression
osteoporosis
normocytic anaemia

Question 14

why does gas trapping occur in expiration?

Answer 14

small airways collapse and trap air

Question 15

______flow limitation occurs in tidal breathing

Answer 15

expiratory

Question 16

what are some effects on lung capacity?

Answer 16

increased end expiratory lung volume (FRC)
decreased inspiratory capacity and inspiratory reserve volume
functional weakness of the diaphragm

Question 17

reduced muscle pump capacity + increased respiratory load = _____neural respiratory drive

Answer 17

increased

Question 18

what causes cor pulmonale in copd?

Answer 18

chronic hypoxia causes pulmonary vasoconstriction which leads to pulmonary hypertension.

Question 19

which viruses can cause copd exacerbations?

Answer 19

influenza/parainfluenza
rsv
human metapneumovirus
coronavirus

Question 20

which bacteria commonly cause exacerbations?

Answer 20

h. influenzae
m. catarrhalis
s. pneumoniae
s. aureus

Question 21

which bacteria are common in severe exacerbations?

Answer 21

pseudomonas aeruginosa

Question 22

what are features of an exacerbation?

Answer 22

increased breathlessness
increased cough
increased sputum
change in colour of sputum
impaired daily activities
raised temp, resp rate,heart rate, bp
low o2 sats
sweaty, confused
polyphonic wheeze
ankle oedema

Question 23

how should a mild exacerbation be treated?

Answer 23

short acting bronchodilators only

Question 24

how should a moderate exacerbation be treated?

Answer 24

short acting bronchodilator
antibiotics
oral corticosteroids

Question 25

why do peripheral muscles fatigue in exercise?

Answer 25

lower limb muscle atrophy reduced muscle metabolism decreased type 1 fibres decreased myosin heavy chain 1 and oxidative enzyme activity

Question 26

what is a typical history for someone in the chronic bronchitis group?

Answer 26

hypoxic, obese, coughing using accessory muscles productive cough intermittent dyspnoea later frequent and recurrent pulmonary infections progressive cardiac/respiratory failure oedema weight gain (due to inactivity)

Question 27

what is a typical history for someone in the emphysema group?

Answer 27

``` thin, barrel chest, dry cough, effort in breathing, wheezing, hyperresonant chest long history of progressive dyspnoea later onset of non productive cough occasional mucopurulent relapses cachexia and respiratory failure ```

Question 28

how does the histology of the airways change in chronic bronchitis?

Answer 28

``` more squamous metaplastic epithelial cells less columnar and ciliiated cells mucous gland hyperplasia basal cell metaplasia squamous metaplasia more macrophages as cd8 t cells NO smooth muscle increase (thats asthma) ```

Question 29

what are neutrophils in the sputum a sign of?

Answer 29

exaerbation due to local infection

Question 30

what enzyme destroys elastic and collagen fibres in emphysema

Answer 30

proteases

Question 31

which genetic deficiency has high rates of emphysema?

Answer 31

alpha 1 antitrypsin deficiency

Question 32

which form of emphysema affects the area of the acinar proximal to the terminal bronchile and is characteristic of smokers?

Answer 32

centrilobar emphysema

Question 33

describe panacinar emphysema

Answer 33

affects the whole acinar characteristic in exposure to smoke or noxious gases and alpha 1 antitrypsin deficiency bullous subpleural airspaces can form due to ruptures

Question 34

what will a chest x ray for copd show?

Answer 34

hyperinflation | clear lung fields (unless pneumonia)

Question 35

what does an increase in sputum purulence in an exacerbation indicate?

Answer 35

bacterial infection

Question 36

how can a severe exacerbation be treated?

Answer 36

``` o2 therapy sabd b2 agonist plus anticholinergic therapy systemic glucocorticoids antibiotics ```

Question 37

what are the target sats for copd:

Answer 37

88% - 92%

Question 38

when should non invasive ventilation be considered?

Answer 38

acute resp acidosis signs of fatigue increased work of breathing persistent hypoxaemia

Question 39

what indicates need for intubation?

Answer 39

``` post cardiorespiratory arrest reduced consciousness arrhythmia haemodynamic instabiility hypoxaemia aspiration/vomiting ```

Question 40

decribe management of stable copd

Answer 40

``` flu vaccine stop smoking education strengthen skeletal muscles bronchodilators - sabas, labas, antimuscarinics, inhaled corticosteroids surgical lung volume reduction lung transplant oxygen ```

Question 41

what are some side effects of beta 2 agonists

Answer 41

increased hr, arrythmias, hypokalemia