42 Pulmonary Mechanics & Ventilation

Question 1

Performs lateral expansion (bucket-handle movement) and anterior expansion (pump handle movement). Used when active and resting

Answer 1

Diaphragm

Question 2

Used during exercise or lung disease. Only used when active (i.e. not resting)

Answer 2

External intercostals

Question 3

Sternocleidomastoid, anterior serrati, and scalenes

Answer 3

Other muscles of respiration

Question 4

The passive process of expiring air. No muscles are involved under resting conditions

Answer 4

Expiration

Question 5

During exercise or lung disease, this muscle group plays a role in forcing air out of the lungs

Answer 5

internal intercostal muscles

Question 6

Used to measure flow and volumes of the lungs. Measures flow, volumes. Volume vs time. Can determine:

Answer 6

Spirometry

Question 7

Volume of air inspired or expired with each normal breath

Answer 7

Tidal volume

Question 8

The extra volume of air that can be inspired over and above the normal tidal volume when the person inspires with full force

Answer 8

Inspiratory Reverse volume

Question 9

The maximum extra volume of air that can be expired by the forceful expiration after the end of a normal tidal expiration

Answer 9

Expiratory reserve volume

Question 10

The volume of air remaining in the lungs after the most forceful expiration

Answer 10

Residual Volume

Question 11

Vt + IRV = ?

Answer 11

Inspiratory capacity (IC)

Question 12

The maximum amount of air that can be expired following a maximal insipration

Answer 12

Vital capacity

Question 13

IRV + Vt + ERV = ?

Answer 13

Vital capacity

Question 14

The most effective way to measure Vital capacity. Ask the patient to inspire as much as possible, then expire as quickly as possible.

Answer 14

Forced vital capacity

Question 15

The volume of air exhaled in the first second of the FVC maneuver

Answer 15

Forced expiratory volume in one second (FEV1)

Question 16

T/F. • Normal people exhale 90% of their VC in 1 second during a forced expiration

Answer 16

False. Normal people exhale 80% of their VC in 1 second during a forced expiration

Question 17

The amount of air remaining in the lungs following a normal expiration

Answer 17

Functional residual capacity (FRC)

Question 18

ERV + RV = ?

Answer 18

Functional residual capacity (FRC)

Question 19

The amount of air in the lungs at the end of a maximal inspiration

Answer 19

Total lung capacity (TLC)

Question 20

IRV + Vt + ERV + RV = ?

Answer 20

Total lung capacity (TLC)

Question 21

Total amount of air moved into and out of respiratory system per minute

Answer 21

Minute ventilation

Question 22

Vt *(x breaths/min) = ?

Answer 22

Minute ventilation

Question 23

How much air per minute enters the parts of the respiratory system in which gas exchange takes place

Answer 23

Alveolar ventilation

Question 24

(VT – dead space) * (x breaths/min) = ?

Answer 24

Alveolar ventilation

Question 25

The volume of air which is inhaled that does not take part in the gas exchange, either b/c it (1) remains in the conducting airways, or (2) reaches alveoli that are not perfused or are poorly perfused

Answer 25

Dead space

Question 26

Region of the lung in which pressure is -10 cm H2O (very negative)

Answer 26

Upper

Question 27

Region of the lung in which pressure is -5 cm H2O

Answer 27

Middle

Question 28

Region of the lung in which pressure is -2 cm H2O. Ventilation is best here. Gravity and airway size contribute to this

Answer 28

Lower

Question 29

Portion of the airways which conducts gas to the alveoli (mouth, larynx, trachea, bronchioles, etc)

Answer 29

Anatomical dead space

Question 30

Alveoli containing air but w/o blood flow in the surrounding capillaries (alveoli that are ventilated, but not perfused)

Answer 30

Alveolar dead space

Question 31

Total dead space in the lung system (anatomic dead space plus alveolar dead space)

Answer 31

Physiologic dead space

Question 32

This represents the forces that develop in the wall of the lung as the lung expands. This force always acts to collapse the lung
• As the lung enlarges, ___ increases; as the lungs get smaller, ___ decreases.

Answer 32

Lung recoil

Question 33

The pressure in the thin film of fluid b/t the lung and the chest wall

Answer 33

Intrapleural pressure (intrahoracic pressure)

Question 34

T/F. Subatmospheric pressures (-) act as a force to expand the lung, and positive pressure (+) act as a force to collapse the lung
• In normal restful breathing, the intrapleural pressure is always subatmospheric pressure or negative, and thus acts as a force to expand the lung

Answer 34

True

Question 35

calculated as Pinside - Poutside. Calculated as Pinside - Poutside. Positive values cause distension while negative values cause collapse

Answer 35

Transmural pressure

Question 36

the change in lung volume divided by the change in the surrounding pressure

Answer 36

Compliance

Question 37

Compliance is inversely proportional to ___

Answer 37

Elasticity

Question 38

1/(radius^4)

Answer 38

Airway resistance

Question 39

T/F. The first and second bronchi in the branching airway system of the lungs represent most of the lungs airway resistance

Answer 39

True

Question 40

___ nerve stimulation produces bronchoconstriction

Answer 40

Parasympathetic (muscarinic receptors) nerve

Question 41

T/F. Circulating glucocorticoids produce bronchodilation

Answer 41

False. Circulating catecholamines (dopamine, epinephrine, norepinephrine) produce bronchodilation

Question 42

These diseases restrict the expansion of the lung parenchyma (the airways are normal)

Answer 42

Restrictive lung disease

Question 43

Ex: COPD, bronchitis, emphysema. In this type of disease, the parenchyma is damaged and can no longer keep the airways open. The lungs are abnormally large in size. The airways can be restricted in size by hypersecretion as well.

Answer 43

Obstructive lung disease

Question 44

T/F. Increased radial traction is present in obstructive lung disease

Answer 44

False. Reduced radial traction is rpesent in obstructive lung disease

Question 45

The degree to which the lung parenchyma is working to keep the airways open (increasing the radius of the airways)

Answer 45

Radial traction