Term
How do local anesthetics work?
In general what is their mechanism of action?
What receptor states do LA work on? |
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Definition
- Block all sensation on a particular part of the body
- Na channel block
- Open/rapidly firing axons
- Resting |
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Term
What determines LA rate of action? |
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Definition
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Term
What are the 3 most common LAs?
What is the most widely used LA? |
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Definition
- Cocaine
- Procaine (Novocaine)
- Lidocaine (Xylocaine)
- Lidocaine (Xylocaine) |
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Term
What else is Lidocaine used for? |
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Definition
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Term
Why is cocaine not used as much as an LA? |
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Definition
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Term
What are the 2 main divisions of LA? |
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Definition
- Amide based
- Ester based |
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Term
What are the 3 ester (has 2 Os) based LA?
Clue: 1 I |
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Definition
- Benzocaine
- Cocaine
- Procaine |
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Term
What are the 3 amide (has an N) based LAs?
Clue: has 2 I's |
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Definition
- Bupivacaine
- Lidocaine
- Prilocaine |
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Term
Where are amide based LAs metabolized?
What are they metabolized by? |
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Definition
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Term
What pH are most LA?
How does lowering the pH effect the LA?
How can this be fixed? |
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Definition
- Weak base @ pH 8-9
- Makes it less effective (keeps it outside the cell)
Increasing dosage |
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Term
What controls the action of LA?
What are LA usually administered w?
Why? |
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Definition
- Absorption/diffusion from site
- Epinephrine
- Its vasoconstriction property -> reduces diffusion from site |
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Term
What determines the toxicity of LA?
Where is one place amide based LA get stored?
What is the main difference as far as toxic effects between Amide based & ester based?
What is the one exception to the rule? |
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Definition
- Distribution
- In fat
- Ester based has no systemic effects
- Cocaine |
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Term
Where are amide based LA metabolized?
What are amide based LA metabolized by?
Where are ester based LA metabolized?
What are ester based LA metabolized by? |
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Definition
Liver
P450/amidases
Plasma
Butyrylcholinesterase
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Term
What on the neuron do LA effect?
What effect does carbonation have on LA?
Where should LA not be used?
What effects do LA have in these areas? |
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Definition
Peripheral nerve endings
Increases effect of LA
Areas w poor perfusion
Ischemia bc of vasoconstriction |
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Term
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Definition
Drug delivery system where LA are delivered along w electical charge |
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Term
What are some toxic effects of LA in general? 5
TTPIA |
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Definition
- Tongue numbness/tingling
- Tonic-clonic convulsions
- PNS desensitization
- Inhibits Na/Ca channels in the heart
- Allergic reactions due to PABA
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Term
Procaine (Novocain)
Amide or Ester?
Metabolized by?
Toxicity?
What is the cure of the last toxicity?
Used as? |
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Definition
- Ester (of diethylaminoethanol & PABA)
- Pseudocholinesterase
- Inhibits sulfonamides
- Methemoglobinemia (damaged form of hemoglobin)
- Methylene blue
- LA |
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Term
Cocaine
Ester or amide?
What does it block?
Effects? 2
Why is it no longer widely used?
Used as? |
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Definition
- Ester (alkaloid)
- Reuptake of NE & DA (catecholamines)
- Euphoria -> depression
- Vasoconstriction
- Highly addictive
- LA |
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Term
Lidocaine (xylocaine)
Ester or amide?
When is it used? 2
Where is it metabolized?
Used as?
What is it metabolized by?
What is it administered with?
What else is it used for? |
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Definition
- Amide
- Infiltration blocks
- Epidural
- Liver
- P450
- Epinephrine
- Antiarrhythmic
- LA |
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Term
What are the 3 goals of GA?
What are the 2 things that determines what "goal" a GA will fulfill? |
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Definition
1) Analgesia (pain killer)
2) Amnesia
3) Unconsiousness
1) Speed of induction
2) Safety |
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Term
What 5 durgs are the GA used in conjunction w & why? |
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Definition
1) Benzodiazepines:
- Reduces anxiety
- Facilitates amnesia
2) Barbituates (phenobarbital)
- Induces sedation
3) Antihistimine (diphenhydramine)
- Reduces allregic reaction
- Recudes stomach acid (cimetidine)
4) Opiates (fentanyl)
- Analgesia
5) Anticholinergics (Scopalamine)
- Reduce secretion of respiratory fluid
- Prevent bradycardia |
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Term
What makes a drug a fast inductor? |
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Definition
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Term
What is the main concern with recovery from anesthesia? |
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Definition
- Diffusion hypoxia w nitrous oxide |
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Term
What are the 4 stages of anesthesia? |
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Definition
1) Analgesia (pain killer)
2) Excitement
3) Surgical anesthesia
4) Medullary paralysis & death |
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Term
What are the 3 gas anesthesias? |
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Definition
1) Halothane
2) Isoflurane
3) Nitrous Oxide |
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Term
How is anesthesia measured?
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Definition
- by minimal alveolar concentration MAC |
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Term
What is the MAC for halothane?
What is the MAC for isoflurane?
What is the MAC for NO? |
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Definition
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Term
How does solubility effect GA?
List the gas anesthetics in order of more soluble to least: |
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Definition
- More soluble -> slower on & off
- Halothane (most)
- Isoflurane (middle)
- NO (least) |
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Term
Halothane
MAC?
What is it usually combined w?
Side effects?
1 reason its still used as a GA?
Used as? |
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Definition
- 0.7%
- NO
- Hepatitis
- Arrhythmias
- Pleasent odor
- GA |
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Term
Isoflurane
What's special about this drug?
MAC?
Whys is it used?
Used as? |
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Definition
- Most commonly used gas GA in US
- 1.2%
- SAFE!!! No side effects
- GA |
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Term
NO
MAC?
Main use?
Side effects?
Used as? |
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Definition
- 105%
- Analgesic
- Diffusion hypoxia
- Peripheral neuropathy
- GA |
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Term
Propofol
Drug class type?
Main use?
Drug combined w & why?
Used as? |
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Definition
- Barbituate
- Most commonly used IV GA for short surgeries
- Opiates to provide pain relief
- GA |
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