Test 1

Question 1

Purpose of Bypass

Answer 1

Bloodless field, maintain adequate tissue perfusion to meet energy demands and ensure full return of function post op
supply=demand

Question 2

How do we meet supply demand goal of perfusion?

Answer 2

1) calculate flow rates (weight or BSA)
2) maintain minimal MAP
3) SvO2
4) urine output
5) acid-base status
6) level of anesthesia

Question 3

What effects O2 consumption (2)

Answer 3

metabolic rate and O2 delivery

Question 4

Tissue O2 Gradients

Answer 4

cap (95) - interstitial (40) = 55 diff

interstitial - intracellular (23)= 17 diff

Question 5

Changes in Intracellular PO2 depend on

Answer 5

PaO2
BF
HCT

Question 6

Managing BF

Answer 6

1) based on weight/BSA

2) O2 Consumption Plateau

Question 7

Managing HCT/Hgb

Answer 7

minimize prime, RAP/VAP, hemoconcentrate, increase urine output, PRBC

Question 8

3 Goal Directed Perfusion Concepts

Answer 8

1) concentration on oxygen delivery (pump flow and HCT) nadir rather than hematocrit (respiratory quotient and DO2/VCO2)nadir
2) use CO2 to indicated tissue perfusion
3) make decisions on concepts and evidenced based values

Question 9

Krogh’s Capillary Cylinder Model

Answer 9

• O2 delivery depends on number and distribution of capillaries
• metabolism changes flow
• each cap supplies radius of tissue