Pulmonary Function Test

Question 1

Indications

Answer 1

Identify changes in pulmonary function

Evaluate needs for therapeutic effectiveness

Surveillance for pulmonary disease

Asses patient for risk of post operative pulmonary complications

Determine pulmonary disability

Question 2

Spirometer

Answer 2

Measured volume and flow

Pneumotachometer ( Flow )

Turbine device ( Wright respirometer )
Measures flow and may display volume

Fleisch pneumotachometer ( flow ) can be used to continuously measure minute ventilation

Question 3

Peak Flow meter

Answer 3

Asthma

Measures and monitor PEFR for patients with asthma

Accuracy is effective by patient effort

Patient needs to blow hard and fast

Repeat procedure 3 times

High test of the 3 scores should be recorded

Peak Flow for a healthy adult is 10 L/Sec or 600 L/min

Question 4

Peak flow ranges

Answer 4

Green zone - 80% to 100% ( 400 L/Min )

Yellow zone - 50% to 80% ( 250- 400 L/Min )

Red Zone - Less than 50% ( less than or = to 250 L/Min )

Question 5

Plethysmograph ( Body Box )

Answer 5

Measures FRC and RV

Boyles law

Thoracic Gas volume ( TGV ) Same as FRC

Measures Airway Resistance

Daily Calibrated with a 3.0 L Syringe

Question 6

Pressure measuring devices

Answer 6

Water manometer or barometer

Measured atmospheric ( barometric ) Pressure

Aneroid Manometer

Question 7

MIP/MEP Device

Answer 7

Measures Pressure

Maximum Inspiratory Pressure

Assess respiratory muscle and impairment

Guillian Barre and Mysathenia Gravis

Normal MIP is 80 ( Range 80-100 )

Intubate when it’s less than 20

Maximum Expiratory pressure

Helpful In Evaluation a patients ability to maintain an airway and clear secretions ( ability to Cough )

Normal MEP is 160

Less than 40 means poor ability to remove secretions

Question 8

Vital Capacity/Slow Vital Capacity

Answer 8

SVC Provides volumes that identify restrictive diseases

Volume and capacities that are
Measured Include :
VT ( Tidal Volume )
IRV ( Inspiratory reserve volume )
ERV ( Expiratory Reserve Volume )
IC ( Inspiratory Capacity, IRV + VT )
VC ( Vital Capacity, IRV + VT + ERV )

DECREASED VOLUME MEANS RESTRICTIVE DISEASE

DECREASED CAPACTIY IS THE BEST INDICATOR FOR RESTRICTIVE DISEASE

Question 9

Forced vital capacity ( FVC )

Answer 9

FVC provides important flow rates used to identify obstructive Disease

Flows that can be measured during FRC
FEV 1 ( Forced Expiratory Volume in 1 sec )
FEF 200-1200 ( FORCED EXPIRATORY FLOW 200-1200 ) Large Airways
FEF 25-75 ( Force expiratory flow 25-75 ) Small Airways

PEFR ) Peak Expiratory Flow Rates ) asthma

Decreased FEV, Indicates obstructive Disease

FEV1/IFVC minimal acceptable is 70%

Deceased FEV/FVC is the best indicator or obstructive disease

Question 10

Pre and Post Bronchodialator Testing

Answer 10

Used to Determine the reversibility of an obstructive disease

Minimum increase of 12% and 200 ML’s in the FEV

All Bronchodialator Therapy should be held 8 hours prior to testing

Question 11

Flow Volume Loop

Answer 11

Y-axis displays expiratory flow rates above the base line and Inspiratory flow are below the base line

X-axis displays volume

Question 12

Interpretation of spirometry

Answer 12

Predicted normal vales are based on
Age
Height
Sex/gender
Race/ethnicity

Question 13

Classification of Spirometry Results

Answer 13

80-100% of predicted = normal PFT
60-79% of predicted = Mild disorder
40-59% of predicted = moderate disorder
Less than 40% of predicted = severe disorder

FVC = volume (restrictive)
FEV1/FVC = flow (obstructive)

Question 14

DLCO
Diffusing capacity

Answer 14

Measures all the factors that affect the diffusion of a gas across the alveolar - capillary membrane

Normal DLCO is 25 mL

Occurs in patients with pulmonary fibrosis, sarcoidosis, ARDS, pulmonary edema, emphysema