Ventilation

Question 1

Which of the following pressure gradients is responsible for maintaining alveolar inflation?

Answer 1

Transpulmonary pressure gradient

Question 2

What happens during normal inspiration?

Answer 2

Transpulmonary pressure gradient widens
Palv drops below that at the airway opening
The pp increases further

Question 3

What is vital capacity

Answer 3

Maximum volume of air that can be exhaled following a maximum inspiration or inhaled following a maximum expiration (4800) (IRV + VT + ERV)

Question 4

Laminar flow found in nose, mouth, trachea

Answer 4

False

Question 5

Which pressure normally remains negative during quiet breathing

Answer 5

Ppl (pleural pressure)

Question 6

The presence of pulmonary surfactant in the alveoli tends to do which of the following

Answer 6

Increase compliance

Question 7

Elastic forces which must be overcome to move air into the respiratory system includes

Answer 7

Elasticity of the lung
Surface tension in the alveoli

Question 8

What is the calculated measurement of a lung compliance?

Answer 8

0.2L

Question 9

Mechanical WOB

Answer 9

Change in pressure x change in volume

Question 10

In healthy lungs total WOB can be attributed to frictional forces

Answer 10

1/3

Question 11

Which is a single indicator of the adequacy of alveolar ventilation

Answer 11

PaCO2

Question 12

Characteristic that could result from a lung that loses elastic fibers

Answer 12

Increased compliance

Question 13

What is normal Raw?

Answer 13

0.5-2.5

Question 14

What is hysteresis?

Answer 14

An air filled lung shows a difference between inspiratory lung volume and expiratory lung volume at any given pressure

Question 15

In normal individuals approximately what fraction of the VT is water during ventilation

Answer 15

1/3

Question 16

The presence of surface tension forces in the air filled lung decreases the elastic recoil of the lung

Answer 16

False

Question 17

What is the normal range of minute ventilation (Ve) in a healthy adult

Answer 17

5-10 L/min

Question 18

All the following statements are true concerning Poiseuilles Law

Answer 18

In order to maintain specific flow as the radius of a tube increases, the driving pressure must increase

Question 19

Total lung-thorax compliance in normal individuals is about what level

Answer 19

0.1 L/cm H2O

Question 20

Which pulmonary conditions can cause an increase in airway resistance

Answer 20

Bronchospasm
Partial obstruction
Mucosal edema
Not fibrosis (red volume)

Question 21

In individuals with disorders characterized by an increased frictional WOB such as emphysema which breathing pattern results in the minimum work?

Answer 21

Slow and deep breathing

Question 22

For healthy individuals at rest which of the following statements about exhalation is true

Answer 22

Exhalation will be passive, due to inspiratory stored potential energy

Question 23

On inspecting a volume pressure curve of a restrictive lung disease below, which of the following characteristics Parrish to this condition

Answer 23

Decreased lung compliance

Question 24

Approximately what % of the total resistance to gas flow occurs in the small airway less than 2mm

Answer 24

20%

Question 25

At the EPP pressure inside the airway exceeds the PPI

Answer 25

False

Question 26

A patient has a tidal volume of 525 ml with RR at 14 his Vd/Vt is 0.4. What’s the patient’s approximate alveolar ventilation

Answer 26

4.4L/min

Question 27

Which of the following formulas are used to compute the time constant of a lung unit

Answer 27

Resistance x compliance

Question 28

How does gravity affect the pleural pressure in an upright lung

Answer 28

The Ppl in the apex is more negative

Question 29

If a patient has a 6mm et tube and was replaced with a 8mm

Answer 29

Less pressure to ventilate

Question 30

Respiration is the process of moving air in and out of the lungs

Answer 30

False

Question 31

In the person lying flat on their back which conditions would be true

Answer 31

The posterior portion of the lungs would o receive the most ventilation

Question 32

What’s condition is an example that presents alveolar dead space

Answer 32

Pulmonary embolus

Question 33

On inspecting a volume pressure curve what type of condition is shown

Answer 33

Obstructive