Podiatry Boards Part 2

What is the MOA of local anesthetics?

Bind Na channel in nerves and block depolarization
What does lipid solubility do for locals?

Penetrate nerve membrane and have greater potency
What does protein binding do for locals?
- influences duration of action
- agents of short duration bind poorly
pKa and pH?
- As pH decreases equilibrium shifts toward cation with binds to receptor.
- pKa defines the pH at which the base and cation forms are equal
- Agents with a pKa closer to tissue pH have a rapid onset
Locals cause dialation why is this good?

more vascular absoprtion less local
Amides are what and metabolized where?
- Locals that have 2 "i"s
- Metabolized in the liver
What agent is used in epidurals?

Bupivicaine and Mepivacaine
What amide really blocks motor control?

Etidocaine
What are signs of CNS toxicity?
- Ringing in the ears
- Light headed
- Confusion
- Tonic-clonic convulsions
- Unconsciousness
- General CNS depression
- Respiratory arrest
What are signs of cardio toxicity?
- HTN
- Tachycardic
- Later bradycardic
- arrythmias
- circulatory collapse
- decreased CO
What does infection do to local?

Decreases its effectivty

Author

dhubbard

189506

Card Set

Podiatry Boards Part 2

Description

Local Anesthetics

Updated

2012-12-14T19:23:25Z

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