pulmonary function testing

Question 1

Upper airway:

Answer 1

Mouth/nose –> trachea

Question 2

Lower airway:

Answer 2

Larynx –> alveoli
- oxygenation problems

Question 3

Airways have multiple layers

Answer 3

– Smooth muscle tissue surrounding the airway
– Epithelial lining made up of
pseudostratified ciliated columnar cells
■ Mucociliary escalator
– Mucus layer that is produced by goblet cells

Question 4

Actions of the pulmonary system

Answer 4

– Oxygenation
– Ventilation

Question 5

Muscles of inspiration

Answer 5

– Diaphragm !
– Intercostals
– Accessory muscles
■ Sternocleidomastoids, Scalene, Trapezius

Question 6

Basic physiology of a breath

Answer 6

– Brain sends signals for muscles to contact –> thoracic volume increases,
thus decreasing alveolar pressure –> air flows into the lungs
– Exhalation is passive, occurs due to elastic recoil of the lung

Question 7

– How easily the lungs return to their normal shape

Answer 7

elasticity

Question 8

– How “stiff” the lungs are
– Change in volume / change in pressure

Answer 8

compliance

Question 9

– change in pressure / change in volume
■ Volume indirectly assessed by measuring flow

Answer 9

resistance

Question 10

Measurement of volume & flow

Answer 10

spirometry

Question 11

maximum inspiration followed by maximum exhalation

Answer 11

forced vital capacity (FVC)

Question 11

The amount of air exhaled within the 1st second of an FVC
maneuver

Answer 11

Forced Expiratory Volume in 1 Second (FEV1)

Question 12

Exactly what it sounds like - Math. FEV1 / FVC x 100 = %

Answer 12

%FEV1/FVC

Question 13

Maximum expiratory effort

Answer 13

Peak Expiratory Flow

Question 14

– Measures the ability of the lungs to transfer gases across the alveolar-capillary membrane
- difference between the volume of CO inhaled and the volume of CO exhaled

Answer 14

Diffusing Capacity of Carbon Monoxide (DLCO)

Question 15

Decreased DLCO

Answer 15

Anemia, carboxyhemoglobin, PE, pulmonary fibrosis, emphysema

Question 16

Increased DLCO:

Answer 16

Polycythemia, exercise, CHF

Question 17

– Uses measurements of volume
and pressure to determine lung
volumes
– Expensive, not as convenient but
most accurate
– Better if patient is unable to
participate in typical spirometry

Answer 17

Plethysmography

Question 18

low FEV1/FVC

Answer 18

obstructive (give bronchodilator like albuterol)

Question 19

normal FEV1/FVC

Answer 19

restrictive

Question 20

– Also referred to as negative inspiratory force (NIF)
– Maximum inspiratory pressure pulled against a closed airway
– Normal -80 to -100
– > - 20 (less negative) suggestive of weakness & need for ventilatory
support
– Helpful in neuromuscular disorders (Guillain-barre, Myasthenia gravis)

Answer 20

Assessing Muscle Strength:
Maximum Inspiratory Pressure (MIP)

• restrictive from some kind of neuromuscular issue and it might affect the diaphragm

Question 21

Tid bits for pulmonary function testing

Answer 21

■ Always get 3 attempts
■ Nose plug helps
■ Take breaks