Pulmonary Physiology

Question 1

What is the equation to calculate the pressure/volume relationship in the lungs?

Answer 1

P1V1 = P2V2

Question 2

As the lung volume increases, what happens to the pressure?

Answer 2

Decreases

Question 3

As the lung volume decreases, what happens to the pressure?

Answer 3

Increases

Question 4

What is the Barometric pressure (Pb) value?

Answer 4

760 mmHg = 0 cm H2O

Question 5

What is the pressure of Oxygen value?

Answer 5

150 mmHg

Question 6

The pressure in the lungs has to be ____ than the barometric pressure in order for air to enter the lungs

Answer 6

LESS

Question 7

Which direction does the chest wall want to go?

Answer 7

Expand

Question 8

Which direction do the lungs want to go?

Answer 8

Collapse

Question 9

From the lungs to superficial, what is the order of the anatomy?

Answer 9

Lungs
Visceral Pleura
Intrapleural space (parietal fluid)
Parietal Pleura
Muscles/ribs

Question 10

Intrapleural pressure (Ppl) is a _____ number

Answer 10

NEGATIVE

Question 11

What is the value of the intrapleural pressure at rest?

Answer 11

-5 cm H2O

Question 12

With inspiration, what happens to the value of the intrapleural pressure?

Answer 12

Volume increases = pressure will decrease
** Intrapleural pressure goes from -5 –> -8 cm H2O
== -8 cm H2O

Question 13

What is the value of the alveolar pressure at rest?

Answer 13

Alveolar pressure = Barometric pressure

== 0 cm H2O

Question 14

With inspiration, what happens to the value of the alveolar pressure?

Answer 14

Volume increases = pressure will decrease
** Alveolar pressure goes from 0 –> -1 cm H2O
== -1 cm H2O

Question 15

Why does air enter the lungs when the alveolar pressure is -1 cm H2O?

Answer 15

It is now LESS than the barometric pressure (0), so air will enter!!

Question 16

What is the equation for the Transpulmonary pressure?

Answer 16

Alveolar pressure - Intrapleural pressure

Question 17

What is the value of the Transpulmonary pressure at rest?

Answer 17

0 - (-5) == 5 cm H2O

Question 18

At REST, Describe the volume, alveolar and intrapleural pressures

Answer 18

Volume = 0
Alveolar pressure = 0
Intrapleural pressure = -5

Question 19

At MID-INSPIRATION, Describe the volume, alveolar and intrapleural pressures

Answer 19

Volume is INCREASING
Alveolar pressure = -1
Intrapleural pressure is decreasing

Question 20

At END of INSPIRATION, Describe the volume, alveolar and intrapleural pressures

Answer 20

Volume has peaked = 500 mL
Alveolar pressure has returned to 0
Intrapleural pressure = -8

Question 21

At MID-EXPIRATION, Describe the volume, alveolar and intrapleural pressures

Answer 21

Volume is DECREASING
Alveolar pressure = +1
Intrapleural pressure is increasing

Question 22

At END of EXPIRATION, Describe the volume, alveolar and intrapleural pressures

Answer 22

Volume = 0
Alveolar pressure = 0
Intrapleural pressure = -5
– back to resting state

Question 23

Minute Ventilation (VE)

Answer 23

Volume of air inspired every minute

= RR X Tidal volume

Question 24

What is a normal minute ventilation?

Answer 24

14 X 500 mL = 7 L/min

Question 25

Area of lungs and airways where gas exchange does NOT occur

Answer 25

Dead space

Question 26

What are the 3 types of dead space?

Answer 26

1. Anatomic 2. Alveolar 3. Physiological

Question 27

Anatomic dead space (mL) is equal to?

Answer 27

A person's weight

Question 28

Alveolar dead space is usually?

Answer 28

0

Question 29

In a healthy person, physiological dead space is equal to?

Answer 29

Anatomic dead space

Question 30

Equation for physiological dead space

Answer 30

Physiological dead space = anatomical dead space + alveolar dead space

Question 31

How do you calculate minute alveolar ventilation?

Answer 31

Subtract dead space from the tidal volume and then multiply by the RR

Question 32

Low compliance means?

Answer 32

Low stretch ability = harder to inflate the lungs

Question 33

High compliance means?

Answer 33

Very stretchable = easy to inflate the lungs

Question 34

At low lung volumes, what is the compliance?

Answer 34

LOW - harder to inflate

Question 35

At normal lung volumes, what is the compliance?

Answer 35

HIGH - easier to inflate

Question 36

At high lung volumes, what is the compliance?

Answer 36

LOW - harder to inflate

Question 37

Difference between inspiration and expiration due to surfactant

Answer 37

Hysteresis

Question 38

With emphysema, compliance is ____

Answer 38

INCREASED - harder to expel air

Question 39

With fibrosis, compliance is ____

Answer 39

DECREASED - harder to inspire air

Question 40

As age increases, compliance

Answer 40

INCREASES

Question 41

Compliance is the opposite of?

Answer 41

Elasticity

Question 42

People with emphysema breathe at ____ volumes

Answer 42

HIGHER

Question 43

People with fibrosis breathe at _____ volumes

Answer 43

LOWER

Question 44

Alveoli hold each other open; thus loss of them will lose forces that normally counter collapse

Answer 44

Interdependence

Question 45

What 2 forces must the work of breathing overcome?

Answer 45

Elastic | Resistant

Question 46

With restrictive lung disease, what work changes?

Answer 46

Elastic

Question 47

With obstructive lung disease, what work changes?

Answer 47

Resistive