Pharmacologic Response to CPB- Exam 3 Flashcards Preview

CV Perf Tech III > Pharmacologic Response to CPB- Exam 3 > Flashcards

Flashcards in Pharmacologic Response to CPB- Exam 3 Deck (124)
Loading flashcards...
1

Pharmacokinetics

What the body does to the drug

2

Pharmacodynamics

How a drug interacts with the body to produce its effects

3

First order kinetics

elimination of a drug occurs at a constant fraction of drug remaining in the body per unit of time

4

Zero order kinetics

when drug administration exceeds the body's ability to clear it, leading to drug accumulation

5

To prevent drug accumulation, what should be done?

Drug infusion rates should be adjusted according to patient response

6

To prevent drug accumulation, what should be done?

Drug infusion rates should be adjusted according to patient response

7

Changes in Pharmacokinetics due to CPB

Hemodilution
Hypothermia
Perfusion
Acid-Base Status
Sequestration

8

Changes in Pharmacokinetics due to CPB

Hemodilution
Hypothermia
Perfusion
Acid-Base Status
Sequestration

9

Hemodilution

Reduction in circulating protein concentration
Reduction in RBC concentration
Reduction in concentration of free drug (unless your pump prime matches exactly)
Alterations in organ blood flow, affecting distribution and clearance

10

Hemodilution

Reduction in circulating protein concentration
Reduction in RBC concentration
Reduction in concentration of free drug (unless your pump prime matches exactly)
Alterations in organ blood flow, affecting distribution and clearance

11

What happens if you add drugs to your prime BEFORE RAP? or AFter RAP?

Lose some when you rap
most of the time you wont have time to add drugs after you rap
usually you'll go on pump right after you rap

12

What happens if you add drugs to your prime BEFORE RAP? or AFter RAP?

Lose some when you rap
most of the time you wont have time to add drugs after you rap
usually you'll go on pump right after you rap

13

Hypothermia

Fluid shifts from intravascular to interstitial space
(altered volume of distribution, increased 3rd spacing)
Vasoconstriction (changes in organ perfusion)
Reduction in enzyme-mediated biotransformation
increased solubility of volatile anesthetics

14

Hypothermia

Fluid shifts from intravascular to interstitial space
(altered volume of distribution, increased 3rd spacing)
Vasoconstriction (changes in organ perfusion)
Reduction in enzyme-mediated biotransformation
increased solubility of volatile anesthetics

15

What are two important things to keep in mind regarding patient during perfusion?

Lungs excluded form circulation (valium, propofol, opioids)
Altered hepatic blood flow - vasoconstriction (fentanyl, propofol)

16

What are two important things to keep in mind regarding patient during perfusion?

Lungs excluded form circulation (valium, propofol, opioids)
Altered hepatic blood flow - vasoconstriction (fentanyl, propofol)

17

Acid Base Status

Altered organ blood flow (ph stat= increase cerebral blood flow)
altered ionization and protein binding

18

Sequestration

Drugs may be taken up by various components of the CPB circuit
-coated tubing
-oxygenators
-hemofilters (many factors influence the movmement of drug across the membrane; degree of protein binding is a major determinant)

19

When administering medications

Ensure you have physician's order or standing protocol authorizing you to administer the medication

The patient is not allergic to the medication
you should have the correct medication, the correct concentration and the correct dosage

Inspect the medication for expiration date, precipitates and sterility

20

When administering medications

Ensure you have physician's order or standing protocol authorizing you to administer the medication

The patient is not allergic to the medication
you should have the correct medication, the correct concentration and the correct dosage

Inspect the medication for expiration date, precipitates and sterility

21

What is in your drug box?

Heparin
Neo-Synephrine
NaHCO3
Lidocaine
MgSO4
Calcium
Potassium
Mannitol

22

What is heparin sodium derived from?

Bovine lung tissue or porcine mucosa standardized for anticoagulant activity

23

How is the potency of heparin sodium determined?

By biological assay using a USP reference standard based on units of heparin activity per milligram

24

Units/Mg Heparin Conversation

100 units = 1 mg
Ex. 5,000 units = 50 mg

25

What is the action of heparin sodium?

Stops coagulation by potentiating antithrombin III and inhibiting the action of activated Factors IX and XI

26

What is the action of heparin sodium?

Stops coagulation by potentiating antithrombin III and inhibiting the action of activated Factors IX and XI

27

How is heparin eliminated?

kidneys

28

What is the half-life of heparin?

At CPB doses is 2 or more hours; prolonged by hypothermia and renal blood flow alterations

29

What is the half-life of heparin?

At CPB doses is 2 or more hours; prolonged by hypothermia and renal blood flow alterations

30

Heparin Side Effects

Activation of t-PA and platelets
Boluses decrease SVR by 10-20%
Anaphylaxis rarely occurs
HIT and HITT