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Flashcards in Local anasthetic agents Deck (10):
1

Which form of LA enters the cell

LA, uncharged

2

MOA of LA

Reversibly blocks open Na+ channels from within the cell. Must enter the cell (LA) and become ionized (LA+) to bind.

3

Order of nerve block for LAs

Pain fibers first
sensation fibers next
motor function blocked last

4

What is potency correlated with for LAs

lipid solubility, more lipid soluble = more potent
Size, smaller size = more potent

5

Effect of vasoconstriction in LA

reduce systemic absorpion. If drug does not have vasoconstriction properties, may add epinephrine

6

metabolism of LAs

Amide LAs metabolized in the liver by CYP P450
Ester LAs metabolized in plasmas by plasma cholinesterase

7

Factors affecting clearance of LAs (4)

Patient age
Liver function
Cardiovascular function
Type of LA, esters degraded faster

8

Systemic toxicity of LAs

Hypersensitivity of metabolites of Ester LAs
Hypersensitivity to methylparaben preservative

9

CNS toxicity of LAs

sedation
lightheadedness
visual and auditory disturbances
tounge numbness and metalic taste
muscular twitching, nystagmus, and convulsions

10

Cardiovascular toxicity of LAs

Most feared toxicity, affect conduction (bupivicaine)
IV infusion of lipid can treat cardiotoxicity