Pulmonary Function Testing

Question 1

Foreced Expiration Test- spirometry is when the patient is asked to inhale maximally then to forcefully expire all air as quickly as possible. what is the FVC and FEV 1?

Answer 1

FVC = total volume exhaled
FEV1 = total volume exhaled in first second (usually
around 75-80% of total volume)

Question 2

note: normal flow curve

Question 3

normal?

Answer 3

this person has expelled a bit less than normal volume as FEV1. could indicate an air flow obstruction

Question 4

in terms of spirometry, what ratio constitutes obstructive lung disease

Answer 4

FEV1/FVC <70% constitutes obstructive

Question 5

in terms of spiromtery, what constitutes restrictive lung disease?

Answer 5

FVC is reduced (\< LLN) and FEV1 is
proportionately reduced (and ‘normal’ FEV1/FVC)

a restrictive lung disease means a TLC reduced

Question 6

for the gas curve, what would indicate an obstructive lung disease?

Answer 6

if there slots of scooping, it can indicate an obstruction

Question 8

whats going on with this report

Answer 8

FEV1/FVC is way below 70. also he flow curve is scooped, it’s a large airway obstruction.

Question 9

So – FVC is reduced in conditions with decreased ___ or
increase ____

Answer 9

So – FVC is reduced in conditions with decreased TLC or
increase RV.

decreased TLC indicates restriction

Question 10

1) Restrictive = Confirmed by Low TLC
due to: 1) reduced ___ of lung 2) reduced compliance of __ ____ 3) weakness of ____ (also increases __)

2) Obstructive= early airway closure - high ___
-recall airway closure is due to bronchial narrowing
from edema/secretions and loss of radial traction

Answer 10

1) Restrictive = Confirmed by Low TLC
1) reduced compliance of lung 2) reduced compliance of chest wall 3) weakness of muscles (also increases RV)

2) Obstructive= early airway closure - high RV
-recall airway closure is due to bronchial narrowing
from edema/secretions and loss of radial traction

Question 11

T/F you can measure funcional residual capacity using spirometry

Answer 11

false. FRC cannot be measured using spirometry but it can be using body plethysmography or gasdilution.

Question 12

on PFT, why might there be a reduced DLCO?

Answer 12

DLCO = diffusion capacity.

• reduced diffusion capacity can be applied via ficks law.
  1. area of membrane reduced (emphysema, lung resection)
  2. thickness increased by swelling (edema, fibrosis, ILD)
  3. pulmonary blood volume reduced by blocked capillaries (pulmonary embolism/pH) or anemia (incorrect for Hb)

Question 13

DLCO can be increased in ___ (expanded pulmonary vasculature) or ___

Answer 13

DLCO can be increased in CHF (expanded pulmonary vasculature) or polycythemia

Question 14

Case 2: 51 year old woman with increasing shortness of breath over 6 months. Has rheumatoid arthritis and is taking methotrexate.

Answer 14

her FEV1/FVC is above 70, and the curve isn’t scooping, probably not obstructive.

her TLC IS LOW THO! this is indicative of restrictive lung disease;

could be due to 1. reduced compliance or lung or chest wall or 2. weakenss of muscles.

Question 15

An 18 year old male with episodic cough and wheeze.

Answer 15

probably asthma

• • Spirometry can be normal or obstructive depending on
  presentation • A significant bronchodilator (BD) response may or may
  not be present.

Question 16

fill out:

Answer 16