What are the contraindications to spiro?
hemoptysis of unknown cause
pneumothorax
unstable cardiovascular status
recent MI or PE
AAA
recent ocular surgery (eg. cataract)
nausea, vomiting
recent thoracic or abdominal surgery
What is the lower limit of normal on Spiro?
measured by the standard deviation of -1.64 which indicates the 95% confidence
What is the measure of significant reversability?
GINA and NICE: rise of at least 12% and at least 200 mL
OR SOME SAY
>15%
Which panels on a 9 panel plot are related to CVS?
panel 2,3 and 5
Which panels on a 9 panel plot are related to ventilation?
panel 1,4 and 7
Which panels on a 9 panel plot are related to ventilation/perfusion?
6, 8 and 9
What is the order of questions we should ask re: PFTs?
- TLC small or higher?
2a. If lung volumes higher, is there gas trapping?
2b. If lower, is there gas trapping? - if Lower with gas trapping, is there airways obstruction?
what is the conclusion if the TLC is high with gas trapping?
Big lungs with abnormal mechanics
what is the conclusion if the TLC is high without gas trapping?
Big lungs, but essentially normal
what is the conclusion if the TLC is high with normal lung volumes with gas trapping?
Big lungs, but essentially normal
what is the conclusion if the TLC is high with normal lung volumes without gas trapping?
normal lung volume
what is the conclusion if the TLC is low with gas trapping and airways obstruction?
Mixed obstruct/restrictive pattern
what is the conclusion if the TLC is low with gas trapping and without airways obstruction?
complex restriction
what is the conclusion if the TLC is low without gas trapping?
simple restriction
What is KCO?
diffusion of CO ie the speed of CO uptake
What is TLCO
Transfer factor of CO ie total diffusion capacity for the lungs
When looking at gas transfer, what is the order of questioning?
- TLCO High or low?
- If Low, what is the alveolar volume?
- If AV is low, what is the KCO?
What is the conclusion if THe TLCO is high?
increased pulmonary blood vol (L to R shunt, asthma, obesity), pul haemmorhage, erthyrocytosis
What is the conclusion if TLCO is low with normal alveolar volume?
Pul vascular abnormality ie OH, PE, vasculitis
What is the conclusion if TLCO is low with low alveolar volume and high KCO?
localised loss of lung volume (pneumonectomy or incomplete expansion- poor technique or MND)
What is the conclusion if TLCO is low with low alveolar volume and low KCO?
low of alveolar cap struction with volume loss
