passmed resp

Question 1

1. causes of upper zone fibrosis

2. causes of lower zone fibrosis

Answer 1

Acronym for causes of upper zone fibrosis:

CHARTS
C - Coal worker's pneumoconiosis
H - Histiocytosis/ hypersensitivity pneumonitis
A - Ankylosing spondylitis
R - Radiation
T - Tuberculosis
S - Silicosis/sarcoidosis

Lower zone:
IPF
CTDs
drug induced 
asbestosis (lung ca and mesothelioma)

Question 2

features of Lung Ca’s

Answer 2

small cell:

ADH
ACTH - not typical, hypertension, hyperglycaemia, hypokalaemia, alkalosis and muscle weakness are more common than buffalo hump etc
Lambert-Eaton syndrome

Squamous cell: -
‘in the wrong place - releases all the weird stuff’
parathyroid hormone-related protein (PTH-rp) secretion causing hypercalcaemia
clubbing
hypertrophic pulmonary osteoarthropathy (HPOA)
hyperthyroidism due to ectopic TSH

adenocarcinoma:
gynaecomastia
hypertrophic pulmonary osteoarthropathy (HPOA)

Question 3

at what pO2 do you offer LTOT to pts with COPD?

Answer 3

COPD - LTOT if 2 measurements of pO2 < 7.3 kPa

or 2 occasions of: a pO2 of 7.3 - 8 kPa and one of the following:
secondary polycythaemia
peripheral oedema
pulmonary hypertension

Question 4

how should you treat an infective exacerbation of pneumonia

Answer 4

increase frequency of bronchodilator use and consider giving via a nebuliser
give prednisolone 30 mg daily for 7-14 days
it is common practice for all patients with an exacerbation of COPD to receive antibiotics. NICE do not support this approach. They recommend giving oral antibiotics ‘if sputum is purulent or there are clinical signs of pneumonia’
the BNF recommends one of the following oral antibiotics first-line: amoxicillin or tetracycline or clarithromycin

Question 5

features of IPF:

Answer 5

progressive exertional dyspnoea
bibasal fine end-inspiratory crepitations on auscultation
dry cough
clubbing

Question 6

diagnosis of IPF:

Answer 6

Diagnosis
spirometry: classically a restrictive picture (FEV1 normal/decreased, FVC decreased, FEV1/FVC increased)
impaired gas exchange: reduced transfer factor (TLCO)

imaging: bilateral interstitial shadowing (typically small, irregular, peripheral opacities - ‘ground-glass’ - later progressing to ‘honeycombing’) may be seen on a chest x-ray

**high-resolution CT scanning is the investigation of choice and required to make a diagnosis of IPF

ANA positive in 30%, rheumatoid factor positive in 10% but this does not necessarily mean that the fibrosis is secondary to a connective tissue disease. Titres are usually low

Question 7

management of IPF:

Answer 7

Management

pulmonary rehabilitation

pirfenidone (an antifibrotic agent) may be useful in selected patients

many patients will require supplementary oxygen and eventually a lung transplant

Question 8

WHAT WOULD YOU SEE ON aspiration of an empyema with pH / gluocse / LDH

Answer 8

Turbid effusion with pH<7.2, Low glucose, High LDH

Question 9

what are the principles of managing COPD patients with

unknown pCO2

normal pCO2 on blood gas

Answer 9

Management of COPD patients
prior to availability of blood gases, use a 28% Venturi mask at 4 l/min and aim for an oxygen saturation of 88-92% for patients with risk factors for hypercapnia but no prior history of respiratory acidosis
adjust target range to 94-98% if the pCO2 is normal

Question 10

management of small cell lung cancer:

Answer 10

Management
usually metastatic disease by time of diagnosis
patients with very early stage disease (T1-2a, N0, M0) are now considered for surgery. NICE support this approach in their 2011 guidelines
however, most patients with limited disease receive a combination of chemotherapy and radiotherapy
patients with more extensive disease are offered palliative chemotherapy

Question 11

managing asthma not controlled on SABA+ICS.. next step?

Answer 11

Following NICE 2017, patients with asthma who are not controlled with a SABA + ICS should first have a LTRA added, not a LABA

Question 12

what does total gas transfer measure? - TLCO

and what conditions is it raised in?

what is a raised transfer coefficient? - KCO

Answer 12

1. an overall measure of the gas exchange in the lungs - measures how much O2 is taken up into the red cells
   ie. raised in conditions where gas exchnage and the alveoli are not affected directly (eg. asthma) and so the lungs compensate by improving the gas exchange
2. raised in asthma / lt to right shunts / exercise etc. - things that increase pulmonary blood flow essentially - to either compensate for something or because of increased pulmoinary blood flow
3. KCO is TLCO divided by the alveolar volume, which makes it a measure of how efficient gas exchange is in relation to the alveolar-capillary surface to volume ratio. In asthma, this is increased because there is increased pulmonary blood flow which increases the number of cells which come into contact with the gas.