Exam 4 - Blood Gas Control

Question 1

4 Blood Gas Concerns

Answer 1

• PaO2
• PaCO2
• SvO2
• pH

Question 2

Normal Arterial PO2

Answer 2

104 mmHg

Question 3

Normal Arterial PCO2

Answer 3

40 mmHg

Question 4

Normal Venous PO2

Answer 4

40 mmHg

Question 5

Normal Venous PCO2

Answer 5

45 mmHg

Question 6

Bypass PaO2

Answer 6

150 - 250 mmHg

Question 7

Increase PO2 w/ Bubble Oxygenator

Answer 7

• Increase # of bubbles….or gas flow (due to more surface area)
  - Also increases PCO2 transfer (due to more bubble volume) …makes it hard to increase PO2 without decreasing PCO2 too
• Perfusionist can only change # of bubbles

Question 8

Gas to blood flow ratio

Answer 8

• Always in format of X:1

- Second value is always 1

Question 9

What can we change in Membrane Oxygenator

Answer 9

• PO2 gradient…. from 120 - 720 mmHg
• PCO2 gradient…. from 0 - 45 mmHg
• Note that in real lung PO2 is = to alveolar/capillary at 104 mmHg
  ~ Not the case in membrane oxygenator

Question 10

How to change Surface Area of membrane oxygenator

Answer 10

• Change out oxygenator

Question 11

How to change O2 level in membrane oxygenator

Answer 11

• Change O2 pressure gradient

Question 12

How to change PCO2 with membrane oxygenator

Answer 12

• Change gas:blood flow ratio

Question 13

Normal SvO2

Answer 13

• 75%

Question 14

How to change SvO2

Answer 14

• Change blood flow
• Change patient O2 consumption
• Add Hct (Hbg)

Question 15

Steps to Blood Gas analysis

Answer 15

• Look at SvO2 (75%)
• Look at PO2 (150-250)
• Look at PCO2 (40)
• Look at pH (7.35-7.45)

Question 16

Calculate new Gas:Blood Flow ratio

Answer 16

• (actual PCO2 / 40) x Original Ratio

- New ratio x Blood Flow