PFTs Flashcards
Introduction:
there are 2 types of ventilatory d/o.. what are they?
Restrictive
Obstructive
Introduction:
Preanesthestic identification and treatment of reversiable ventilatory defects are essential to improve outcomes. What si teh easist amenable to treat? what type is generally difficult to reverse and treat?
Easy - COPD
Difficult - restrictive d/o
Introduction:
it is desireable to perform spirometry on all pts w/ unexplained dyspnea ad in those whom COPD is suspected. A (increase or decrease) in FEV1/FVC is characteristic of obstruction dz
Decrease
Introduction:
what does spirometry help do?
distinguish restrictive ventilatory defects from obstructive ventilatory defects
Introduction:
what provides an alternative method for assesing Pulmonary function?
Flow-volume loops
Introduction:
what are 2 advantages of flow-volume loops over spirometry?
early detection of COPD
differentiate anatomic location of obstruction
Spirometry:
what 5 Lung volumes and capacities are obtained form Spirometric recording?
TIdal Volume (TV)
Vital Capacity (VC)
Inspiratory capacity (IC)
Inspiratory reserve volume (IRV)
Expiratory reserve volume (ERV)
Spirometry:
what 3 lung volumes are not directly obtainable
FRC
Residual Volume (RV)
Total lung capacity (TLC)
what are 3 ways to measure FRC
helium Dilution
Nitrogen washout
Body Plethysmography
Spirometry: Static
Label this
Draw this out for boards
Spirometry: Static
what makes up FRC
ERV + RV
Spirometry: Static
what makes up inspiratory capacity (IC)
Tv + IRV
Spirometry: Static
what makes up VC
ERV + IC
What does the following stand for:
FEV1
Forced Expiratory Volume in 1 sec
this is the volume of gas that can be exhaled within 1 sec of begining forced expiration
What does the following stand for:
FVC
Forced Vital Capacity
this is the volume of gas that can be exhaled during a forced expiratory maneuver
What does the following stand for:
FEV1 / FVC
ratio used to distinguish between restricive and obstructive disease
What does the following stand for:
FEF 25-75
forced expiratory flow from the point where 25% of the FVC has been exhaled to the point where 75% FVC has been exhaled.
the FEF 25-75 is best for assessing what?
small airway disease
Obstructive Disease:
what are 4 types
Asthma
COPD
Chronic Bronchitis (blue Bloater)
Emphysema (pink puffer)
Restrictive Disease:
what are 4 examples
Pulmonary fibrosis
Pneumothorax
Chest wall dz (scoliosis)
NM disease (ALS, MG)
FEV1/FVC ratio:
what is normal value?
> 0.7
FEV1/FVC ratio:
normal picture
FEV1/FVC ratio:
how is Obstructive Dz diagnosed?
if both FEV1 and FVC are low and the Ratio is
FEV1/FVC ratio:
how is restrictive Dz diagnosed
if both FEV1 and FVC are low and the ratio is >0.7
FEV1/FVC ratio:
a comparison of all 3
What is normal FEV1
4L
(think of V/Q 4/5)
what is normal FVC
5L.min
thik of V/Q
4/5
FEV1/FVC ratio: Problems state is restrictive or obstructive dz
FEV1 = 3.6
FVC = 4.8
0.75
Normal
FEV1/FVC ratio: Problems state is restrictive or obstructive dz
FEV1 = 1.8
FVC= 2.2
0.81
Restrictive
FEV1/FVC ratio: Problems state is restrictive or obstructive dz
FEV1 = 2.2
FVC = 4.8
0.45
obstructive
Flow Loop:
where is inspiration on the graph?
lower half
Flow Loops:
Where is Expiration of the graph
Top half
