Upper and Lower Respiratory Problems

Question 1

inspiration

Answer 1

diaphragm contracts drawing air into lungs, as volume increases, velocity decreases –> settling of dust in lungs

Question 2

exhalation

Answer 2

lungs passively return to pre-inspiratory volume

Question 3

conductive airways

Answer 3

not involved in gas exchange

Question 4

acinar airways

Answer 4

main area of gas exchange

Question 5

pulmonary ____ receives entire blood volume of ____ heart

Answer 5

artery, right

Question 6

mean pulmonary pressure =

Answer 6

20cm H2O, low which allows better prefusion and improved exchange of gas

Question 7

___ holds deoxygenated blood

Answer 7

arteries

Question 8

___ holds oxygenated blood

Answer 8

veins

Question 9

capillaries have a thin wall and are easily damaged –> leakage of RBCs & plasma into alveoli. what are 2 causes of capillary damage?

Answer 9

• pulmonary overinflation

- pulmonary hypertension

Question 10

alveoli, “300 million bubbles”, are UNSTABLE and will collapse due to surface tension. what mixes with fluid lining alveoli to increase stability?

Answer 10

surfactant

Question 11

gas exchange is rapid and efficient, each RBC spends __ second in capillary network

Answer 11

3/4

Question 12

name 2 airway defenses

Answer 12

• mucocilary elevator

- alveolar macrophages

Question 13

*tidal volume

Answer 13

volume of air inspired/expired with normal breath (10mL/kg), Vt=Vd (dead space ventilation) + Va (alveolar ventilation)

Question 14

inspiratory reserve volume

Answer 14

amt above resting inhalation

Question 15

expiratory reserve volume

Answer 15

exhale maximally pushing all the air out that you can

Question 16

residual volume

Answer 16

air that can’t be exhaled due to dead space

Question 17

total lung capacity

Answer 17

includes residual, expiratory reserve, resting tidal, and inspiratory reserve, that is all the air your lungs could hold, the maximum volume

Question 18

vital capacity

Answer 18

this s what we use functionally, it doesn’t include residual b/c you can’t move that air

Question 19

*minute ventilation

Answer 19

total amt new air moved into respiratory passages each minute, Vm=RR (for 1 minute)*Vt

Question 20

in regards to dead space ventilation, what % of air breathed in is being used for gas exchange in a dog?

Answer 20

35%

Question 21

in regards to dead space ventilation, what % of air breathed in is being used for gas exchange in a horse/cow?

Answer 21

50%

Question 22

____ dead space must be considered in anesthetized patient

Answer 22

apparatus (ET tubes & respirator tubes)

Question 23

*functional residual capacity

Answer 23

volume of air remaining in lungs after exhalation, measure indirectly

Question 24

*what is the volume of alveolar air replaced with each breath?

Answer 24

~1/7th total alveolar air

Question 25

decreased fractional residual capacity & tidal volume -->

Answer 25

HYPOXIA

Question 26

hypoxia

Answer 26

abnormally low partial pressures O2 in tissues

Question 27

what causes hypoxia?

Answer 27

low O2 delivery to tissues due to anemia (decreased oxygen to tissues) or poor circulation (shock)

Question 28

hypoxia -->

Answer 28

anaerobic metabolism & .:. decreased CO2

Question 29

hypoxemia

Answer 29

low partial pressure O2 in arterial blood, *PaO2

Question 30

**List 5 reasons why a patient will have hypoxemia

Answer 30

- hypoventilation - ventilation-perfusion mismatch - anatomic shunt - diffusion impairment - low FiO2 (fractional inspired oxygen)

Question 31

hypoventilation

Answer 31

ventilation inadequate for gas exchange

Question 32

hypoventilation -->

Answer 32

hypercarbia (increased PaCO2), *PaCO2 > 45mmHg

Question 33

*with hypoventilation there is an ______ relationship between Va & PaCO2

Answer 33

inverse

Question 34

list 4 causes of hypoventilation

Answer 34

- decreased RR - decreased tidal volume - increased metabolic rate - hyperthermia

Question 35

perfusion is ____ in zone 1

Answer 35

absent

Question 36

perfusion is ____ in zone 2

Answer 36

sporadic

Question 37

perfusion is ____ in zone 3

Answer 37

constant

Question 38

with great perfusion and an obstructed alveoli you will see

Answer 38

decreased O2 and slightly increased CO2

Question 39

*with ventilation perfusion mismatch, you want it to essentially be __, you want perfusion & ventilation to be ____

Answer 39

1, equal

Question 40

V/Q inequality impairs exchange of all gases, ____ will be the most effected, ____ exchange impaired but can be corrected with ____

Answer 40

oxygen, CO2, increased ventilation

Question 41

in a V/Q mismatch you will see ___ A-a gradient & ___ PaO2

Answer 41

high (A-a gradient > 30mmHg), low (PaO2

Question 42

anatomical shunt

Answer 42

extreme V/Q mismatch, abnormal vascular connection btwn small pulmonary artery & vein, venous blood mixes w/ arterial blood, deoxygenated blood goes back into the body, this is an example of normal ventilation but no perfusion

Question 43

why won't oxygen supplementation improve the oxygen status for a patient with an anatomic shunt?

Answer 43

patient is ventilating fine and can take in oxygen from the air but it can't get blood to the alveoli to exchange that oxygen

Question 44

is hypoxemia more severe with R to L or L to R shunts? why?

Answer 44

R to L shunt SEVERE HYPOXEMIA b/c R is going to be deoxygenated and will bring all that deoxygenated blood back to the body

Question 45

how does a R to L shunt develop?

Answer 45

pressure increases in RV & PA --> pulmonary hypertension --> RV & PA pressure increase LV & aorta

Question 46

diffusion rate is proportional to

Answer 46

area, partial pressure difference, & solubility of gas (CO2 >>>> O2)

Question 47

diffusion rate is inversely proportional to

Answer 47

tissue thickness & molecular weight

Question 48

list 3 causes of diffusion impairment

Answer 48

- pulmonary fibrosis - decreased RBC transit time through alveolar capillaries - thickening of blood-gas interface (smoke inhalation & pneumonia)

Question 49

low partial pressure of inspired oxygen (altitude sickness) is due to

Answer 49

higher altitudes result in lower atmospheric pressure, all other things being equal

Question 50

PaO2 @ sea level =

Answer 50

150mmHg

Question 51

PaO2 @ 5,000ft above sea level =

Answer 51

124mmHg