Respiratory diseases

Question 1

Type I respiratory failure

Answer 1

Hypoxia - PaO2 below 8.0 kPa

Question 2

Type II respiratory failure

Answer 2

Hypoxia (PaO2 below 8.0 kPa) with hypercapnia PaCO2 >6.0kPa

kidneys have not yet compensated

Question 3

What is respiratory failure

Answer 3

Inadequate gas exchange due to impaired pulmonary ventilation and/or perfusion - leads to altered respiratory blood gas composition​

Question 4

Symptoms of respiratory failure

Answer 4

symptoms of the underlying cause together with symptoms of hypoxia with/without symptoms of hypercapnia

Question 5

(GOLD) criteria for COPD diagnosis

Answer 5

a post-bronchodilator FEV1/FVC <0.70

Question 6

At what level of the lungs do rales (crackles) and rhonchi (wheezing) come from?

Answer 6

“rales in the tails, ronchi in the bronchi”

• rails is at the level of the alveoli (fluid in alveoli)
• ronchi is at the level of the bronchi (mucus, inflammation of bronchi)

Question 7

Signs of COPD

Answer 7

barrel chest
distant breath sounds on auscultation
hyper-resonance on percussion
wheezing (ronchi) - common in exacerbation
crackles (rales) - common in exacerbation

Question 8

Two diseases under the COPD umbrella

Answer 8

chronic bronchitis

emphysema

Question 9

Pathology of emphysema

Answer 9

smoking > inflammation > destruction of structural proteins esp. elastin > less elastic recoil, alveoli collapse (air trapping), alveoli septa collapse - larger alveoli

Question 10

Pathology of chronic bronchitis

Answer 10

smoking > hypertrophy and hyperplasia of mucus glands and goblet cells
too much mucus produced - block airways
cilia less mobile
rely on coughing to shift mucus

Question 11

Pathology of bronchiectasis

Answer 11

Mucocillary escalator not functioning properly > mucus accumulation > bacteria in mucus multiply > pneumonia > recurrent pneumonia > chronic inflammation > structural protein destruction > lungs are stiff (due to collagen laid in repair), airways are dilated and mucus clogged

Question 12

What is chronic bronchitis?

Answer 12

A treatable, preventable disease characterised by airflow limitation.

Defined by clinical features – a productive cough.

Question 13

What is emphysema?

Answer 13

A treatable, preventable disease characterised by airflow limitation.

Defined by structural changes – enlargement of the airspaces.

Question 14

What is bronchiectasis?

Answer 14

Permanent dilation of bronchi due to destruction of the elastic and muscular components of the bronchial wall

Question 15

symtoms of COPD

Answer 15

breathlessness- esp when active
cough
frequent chest infections
persistent wheezing

may be periods of flare up (exacerbations)

Question 16

symptoms of bronchiectasis

Answer 16

persistent cough which brings up phlegm/sputum

breathlessness

Question 17

Symptoms of hypoxia

Answer 17

Dyspnoea; restlessness; agitation; confusion; central cyanosis. If longstanding hypoxia: polycythaemia; pulmonary hypertension; cor pulmonale.

Question 18

Symptoms of hypercapnia

Answer 18

Headache; peripheral vasodilation; tachycardia; bounding pulse; tremor/flap; papilloedema (optic disc swelling); confusion; drowsiness; coma.

Question 19

Cause of type I respiratory failure

Answer 19

V/Q mismatch, hypoventilation, abnormal diffusion, right to left cardiac shunts

Question 20

Cause of type II respiratory failure

Answer 20

Hypoventilation with or without V/Q mismatch

Question 21

Examples of conditions that cause V/Q mismatch

Answer 21

pneumonia
asthma
pulmonary fibrosis 
emphysema
PE
pulmonary oedema 
ARDS