ch 6

Question 1

how much oxygen dissolves in 100mL of blood for leach 1 mmHg of PaO2

Answer 1

.003mL

Question 2

equation oxygen dissolved in plasma

Answer 2

PaO2 x .003

Question 3

normal hb ranges for men and women

Answer 3

men:14-16
women: 12-15

Question 4

how much oxygen can each gram of Hb carry

Answer 4

1.34ml

Question 5

equation for oxygen bound hemoglobin

Answer 5

1.34 x Hb x saO2

Question 6

calculate CaO2 (arterial blood)

Answer 6

(1.34 x Hb x SaO2)+ (.003xPaO2)

Question 7

normal values for CaO2

Answer 7

19.5mL/dLO2

Question 8

normal value for CvO2

Answer 8

15.2 mL/dLO2

Question 9

normal C(a-v)O2

Answer 9

5mL/dLO2

Question 10

two clinical conditions that increase C(a-v)O2

Answer 10

-decrease cardiac output
-exercise
-hypoxia

Question 11

two clinical conditons that decrease C(a-v)O2

Answer 11

-increase cardiac output
-skeletal muscle relaxation
-improved O2 delivery

Question 12

what does P50 measure and what is the normal values

Answer 12

measures Hb affinity of O2
Normal: 27mmHg

Question 13

lower P50

Answer 13

left shift
-increase Hb affinity
-decrease temp
-decrease PaO2
-decrease 2-3 dpg
-increase pH

Question 14

higher p50

Answer 14

right shift
-decrease hb affinity
-increase temp
-increase PaO2
-increase 2,3 DPG
-decrease pH

Question 15

SaO2(90%,75%,50%):PaO2

Answer 15

SaO2(90)= 60mmHg PaO2
SaO2(75)= 40mmHg PaO2
SaO2(50)=27mmHg PaO2

Question 16

equation to calculate PAO2

Answer 16

FiO2(patm-ph20)-PaCO2/RQ

RQ=.8
ph20=47
patm=astmospheric pressure

Question 17

normal P(A-a)O2

Answer 17

7-15mmHg

Question 18

acceptable P(A-a)O2 on 50%

Answer 18

<50mmHg

Question 19

acceptable P(A-a)O2 on fiO2 100%

Answer 19

<100mmHG

Question 20

normal A-a gradient indicate

Answer 20

-hypoventilation
-increased altitude

Question 21

3 causes of increase A-a gradient

Answer 21

-high V/Qmismatch
-intrapulmonary shunt
-impaired diffusion

Question 22

PaO2/FiO2

Answer 22

determines the extend of lung diffusion effects

Question 23

equations for DO2
total oxygen delivery

Answer 23

DO2=COxCaO2x10

CO=cardiac output
CaO2=(1.34 xHbxSaO2)+(.003xPaO2)

Question 24

normal DO2 in mL/min

Answer 24

1000mL O2/min

Question 25

two factors that increase DO2

Answer 25

-increase arterial oxygen saturation -increase HB concentration -increase cardic output

Question 26

two factors that decrease DO2

Answer 26

-decrease arterial oxygen saturation -decrease Hb concentration -decrease cardiac output

Question 27

equation for VO2 oxygen consumption

Answer 27

VO2=COxC(a-v)O2x10 CO=cardiac output C(a-v)O2= CaO2-CvO2

Question 28

normal VO2 in mL/min

Answer 28

250mL

Question 29

two conditions that increase VO2

Answer 29

-seizures -exercise -hyperthemia -increase body size

Question 30

two conditions that decrease VO2

Answer 30

-skeletal muscle relaxation -shunting -poison -hypothermia -decrease body size

Question 31

normal pulmonary shunting percentage

Answer 31

3-5%

Question 32

what percentage is shunting considered life-threatening

Answer 32

20% or greater

Question 33

shunting percentage of P(A-a)O2

Answer 33

100=10% 200=15% 300=20% 400=25%

Question 34

define hypoxemia

Answer 34

low PaO2 in the blood confirmed through ABG

Question 35

define hypoxia

Answer 35

low oxygen in the tissue

Question 36

match hypoxia (hypoxic,anemic,circulatory, histotoxic) with primary cause

Answer 36

-hypoxic-decrease PaO2 -anemic-decrease Hb carrying capacity -circulatory- blood flow to tissue cells inadequate -histotoxic- poison impaired tissue ability to receive O2

Question 37

what is cor pulmonale and what causes it

Answer 37

right heart failure-->pulmonary hypertension (increase CVP) cause: - increase viscosity of blood -increase vascular resistance -obliteration of pulmonary cap bed

Question 38

define polycythemia and how does it affect blood viscocity

Answer 38

-increase red blood cell levels -increase viscosity due to increase RBC

Question 39

why is polycythemia common in chronic hypoxia

Answer 39

increase RBC to try to increase O2 carrying capacity