Pulmonary Mod. 2 Ventilation

Question 1

Ventilation

Answer 1

MECHANICAL PROCESS by which ambient air is brought into and exchanged with air in the lungs

Question 2

Respiration

Answer 2

GAS EXCHANGE. That occurs in lungs (alveolar/capillaries) and throughout the body

Question 3

Ventilation rate

Answer 3

of breaths per minute

Question 4

Alveolar Ventilation

Answer 4

volume of air that reaches alveoli per minute

Question 5

Dead Space Ventilation

Answer 5

volume of air that DOES NOT reach alveoli per/min

Question 6

Respiratory Center in Brain stem

Answer 6

Dorsal Respiratory group in medulla (DRG)

ventral respiratory group in medulla (VRG)

Pneumotaxic & Apneustic Centers Centers in Pons

Question 7

DRG

Answer 7

Action–inspiratory
Function: autonomic rhythm of breathing
receives input from respiratory centes (periphral, chemo, central, lung receptors)

mechanism for blood CO2 and O2 levels to influence rate of ventilation

Question 8

VRG

Answer 8

Action– inspiratory & expiratory

Function: active when increased ventilation is required (not acitve during rest)

Question 9

Pneumotaxic & Apneustic Center in Pons

Answer 9

modify depth and rate of resp.

Question 10

What can override autonomic control?

Answer 10

motor cortex, hypothalmus & limbic system (stress/emotion)

Question 11

4 Lung Receptors

Answer 11

1) send impulse to DRG to influence Ventilation
2) Irritant Receptors
3) Stretch receptors
4) J-receptors

Question 12

Irritant Receptors In Lung

Answer 12

located in epithelium of conducting airway
stimulated by noxious gas, particles,
action–cough reflux, bronchioconstriction, increased ventilation rate

Question 13

Stretch Receptor In Lung

Answer 13

located in smooth muscle of cunducting

Stimulus–prevents over inhaling esp newborns (hering-breuer expiratory reflux)

Action–decrease ventilation

Question 14

J-Receptors of Lung

Answer 14

located near alveolar septum of capillaries
Stimulus–elevated pulmonary capillary pressure
Action–rapid shallow breathing, decrease HR & BP

Question 15

Chemoreceptors

Answer 15

central&peripheral chemoreceptors monitor pH,PaCO2, PaO2

Question 16

Central Chemoreceptors

Answer 16

located in brainstem close to respiratory centers.

monitor physiology majority of the time (healthy conditions)

Question 17

Stimulus for Central Chemoreceptors

Answer 17

detect changes in pH levels of CSF

CO2 diffuses into CSF, CO2 binds w/ H20=H2CO3 which disassociates into H+ and HCO3, and H+ in CSF decreases pH which is recognized

Question 18

Action of Central Chemoreceptor

Answer 18

if PaCO2 increases, stimulates respiratory center to increase ventilation

Question 19

Peripheral Chemoreceptor

Answer 19

located in Carotid (at birfurcation of ICA&ECA) and aortic bodies (aortic arch)

Question 20

Stimulus & Action of peripheral Chemoreceptor

Answer 20

Stimulus–changes in PaO2

Action–increased ventiltion via DRG

Question 21

Which chemoreceptors are more sensitive?

Answer 21

the CENTRAL CHEMORECEPTORS are more sensitive to increased PaCO2 than the peripheral will be to decreased PO2

Question 22

Muscles involved in Inspiration

Answer 22

Rest: diaphragm+external intercostals

Exercise/Disease state–accessory, SCM, scalenes

Question 23

Muscles involved in Expiration

Answer 23

Rest: none, elastic recoil

Exercise/Disease-acessory muscles, abd and internal intercostals

Question 24

Surfactant’s role in the mechanics of breathing

Answer 24

lowers surface tension (allows alveoli to expand)

Question 25

What pressure gradients drive gas exchange

Answer 25

higher O2 pp in alveoli vs pulmonary capillaries (promotes O2 diffusion into blood)

Higher blood stream CO2 pp in pulmonary capillaries vs alveoli (promotes CO2 diffusion into alveoli)

Question 26

Tidal Volume (TV)

Answer 26

500ml

volume of air inspired/expired w/normal breath

Question 27

Inspiratory Reserve Volume (IRV)

Answer 27

3,000-3,300ml

volume of air that can be inspired over/above TV (used w/exercise)

Question 28

Expiratory Reserve Volume (ERV)

Answer 28

1,000-1,2000ml

volume that can be expired after expiration at tidal volume

Question 29

Reserve Volume (RV)

Answer 29

1,200ml
Volume of air that remains in the lungs after maximal expiratrion
(cant be measured by spirometry)

Question 30

Forced Vital Capacity FVC

Answer 30

4,500-5,000ml

TV+IRV+ERV+=VC (maxing out inspiration/expiration)

Question 31

Total Lunch Capacity (TLC)

Answer 31

5,700-6,200

sum of all 4 lung volumes

Question 32

Normal FEV1/FVC

Answer 32

70%-90%

Question 33

Abnormal FEV1/FVC

Answer 33

less than 70

greater than 90

Question 34

What kind of pathology would make the FEV1/FVC less than 70%

Answer 34

obstructive disease

Question 35

What kind of pathology would make the FEV1/FVC more than 90%

Answer 35

restrictive disease, fibrotic pathology, alveoli cant stretch as much, so it actually pushes the air out qucker

Question 36

Minute Ventilation (Ve)

Answer 36

RRxTV
(respiratory rate x tidal volume)

at rest approx 6L

(12respX500mL)=6L

Question 37

Max Ve (maximum minute ventilation)

Answer 37

max volume of air moved in/out of lungs during exercise

healthy: 60-70% of MVV

can be as high as: 100-200L

Question 38

FEV1 to FVC Ratio

Answer 38

percentage of FVC that can be expired in one second

Question 39

Percentage of O2 in Trachea

Answer 39

20.9%

Question 40

Partial Pressure of CO2 in Trachea

Answer 40

.03%

Question 41

Partial Pressure of O2 in Alveoli

Answer 41

14.5%

Question 42

Partial Pressure of CO2 in Alveoli

Answer 42

5.5%