1. What is the significance of the spirometry results ?

2. What size of change is usually regarded as abnormal ?

3. What confirmatory tests could be performed ?

4. What is the prognosis in most cases ?

Answers to part A

1. What is this form of abnormal f/v curve due to ?

2. What condition does it characterise ?

3. Interpret the lung volumes.

4. Why is the VA so much lower than the TLC ?

Answers to part 2

1. What pattern of abnormality is seen here ?

2. What is the possible cause of this pattern of abnormality ?

3. The F/V expiratory curve has a serrated appearance. Of which condition is this said to be characteristic ?

4. Why is it characteristic ?

Answers to part 3

Answers

Question A

1. What is the significance of the spirometry results?

fall in FEV1 suggests diaphragmatic paresis.

2. What size of change is usually regarded as abnormal?

15% fall in FEV1

3. What confirmatory tests could be performed to establish the diagnosis?

US of diaphragm and / or phrenic nerve stimulation

4. What is the prognosis in most cases?

generally good with significant return of function in idiopathic or post viral cases over a 3 year period

back to part A

On to part B

Question B

1. what is this form of abnormal f/v curve due to?

pressure dependent airway collapse

2. what condition does it characterise?

emphysema

3. interpret the lung volumes.

gas trapping

4 why is the VA so much lower than the TLC?

gas trapping leading to poor gas mixing on the single breath test

Back to part 2

On to part 3

QUESTION C

1. what pattern of abnormality is seen here?

restrictive

2. what are the possible causes of this pattern of abnormality?

weak muscles / ILD / msk deformity

3. the f/v expiratory curve has a serrated appearance. Of which condition is this said to be characteristic?

SAS

4. Why?

Variable collapsibility producing oscillation of airway calibre during expiration.