Respiratory

Question 1

67 yo female, admitted with drowsiness, cough with green sputum, diagnosis of asthma and currently smokes 15 cigarettes a day. GCS 12/15. Oxygen saturation is 95% on 40% FiO2. Chest exam shows widespread wheezing with no focal crepitations. 
ABG:
pH = 7.28
PaO2 = 9.5
PaCO2 = 10.6
HCO3 = 28

What type of respiratory failure is this?
How do you treat her?

Answer 1

high carbonate level suggests chronicity so this is not an acute event so more likely to have COPD than asthma

cautious oxygenation (reduce FiO2) as sats are over 92%
treat underlying cause with bronchodilators, steroids +/- antibiotics
1 hr medical treatment then repeat ABG
If non-resolving, may need NIV or invasive ventilation

Question 2

25 yo female. 36/40 pregnant. Admitted for breathlessness with chest pain. Saturating 97% on 4 litres. 
ABG:
pH = 7.38
PaO2 = 19.5
PaCO2 = 3.2
HCO3 = 24
sats = 97.5%
What do you do next?

1. Type 1 RF - increase FiO2
2. Type 1 RF - consider CPAP
3. Type 2 RF - start NIV
4. Adequate oxygenation - do nothing
5. Adequate oxygenation - reduce oxygen despite SOB and concern re PE.

Answer 2

Adequate oxygenation - reduce oxygen despite SOB and concern re PE.

Question 3

19 yo woman admitted for breathlessness. Known asthmatic. ABG normal on 2 L/min oxygen except PaCO2 is slightly raised at 6.4. What do you do next?

A. continue current treatment
B. Increase FiO2
C. Decrease FiO2
D. Trial CPAP
E. Urgent ITU review with view to intubation

Answer 3

E. Urgent ITU review with view to intubation as she is known to have asthma and you would except her Co2 to be low as they blow it off (hyperventilate). Raised CO2 is a serious concern as it shows they’re getting tired and not because she is not adequately oxygenated.

Question 4

How does COPD differ from asthma?

Answer 4

late onset
predominantly smokers
relentless progressive SOB and wheezing
less diurnal and day-to-day variation
winter symptoms
sputum production

Question 5

How would you assess asthma severity?

Answer 5

acute attack: clinical exam

non-acute: RCP3 questions

1. have you had difficulty sleeping due to your symptoms in the last month?
2. have you had the symptoms during the day?
3. has your asthma interfered with your daily activities?

Question 6

What are the 3 main underlying pathological mechanisms in COPD?

Answer 6

loss of elasticity and alveolar attachments
inflammation and scarring
mucus secretion

Question 7

What is an exacerbation of COPD?

Answer 7

An acute event characterised by a worsening of the patient’s respiratory symptoms that is beyond normal day-to-day variations and leads to a change in medications.

Question 8

What would you expect to see on the chest x-ray of a COPD patient?

Answer 8

over-inflation of lungs with low, flattened diaphragm and presence of large bullae where there are focal regions of emphysema

Question 9

What would you expect to see on the chest x-ray of a patient with bronchiectasis?

Answer 9

tram track airways, ring shadows, cysts

Question 10

What would you expect to see on the high resolution CT scan of a patient with bronchiectasis?

Answer 10

signet ring sign (increased bronchoarterial ratio), bronchial wall dilation and thickening

Question 11

What would you expect to see on the chest x-ray of a patient with pneumonia?

Answer 11

air bronchogram in consolidated area
multi-lobar suggests s. pneumoniae
multiple abscesses suggest s. aureus
air fluid level in abscess
upper lobe cavity =kleb (or TB)
diffuse shadowing = viral or PCP
pleural collections