Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neurology 2 > Local Anesthetics - Kruse > Flashcards

Local Anesthetics - Kruse Flashcards

1
Q

Function of local anesthetics

A

Bind and block VGSC’s w/in nerves, blocking action potential potentiation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

2 classes of local anesthetics (w/ members)

A

Amides - Lidocaine, Mepivacaine, Bupivacaine, Ropivacaine, Articaine

Esters - Benzocaine, Cocaine, Procaine, Tetracaine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How to remember which ones are amides (vs. esters)?

A 
Amides = have 2 "i"s in the name
Esters = have 1 "i" in the name
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Duration of action of amides vs. esters

A

Esters - more prone to hydrolysis = shorter duration of action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What may be indicated to be used with the shorter duration drugs (esters)?

A

Vasoconstrictors (epinephrine) - to reduce systemic absorption and destruction (alpha-1 agonist)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

How is cocaine unique?

A

Intrinsic sympathomimetic vasoconstrictive properties (only ester that does NOT need epinephrine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Metabolism of esters vs. amides

A

Esters - PLASMA butyrylcholinesterase

Amides - LIVER P450 enzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Potential contraindication to using amides

A

Hepatic disease - can accumulate amide drug metabolites and cause toxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Potency of local anesthetics

A

More lipophilic = more potent = longer duration of action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which are the more lipophilic ones?

So?

A

Tetracaine, Bupivacaine, Ropivacaine

More potent and longer duration of action

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which nerve fibers are blocked more often by local anesthetics?

A

Smaller, more myelinated fibers
Motor before sensory (motor = more peripheral)
Proximal sensory before distal sensory (extremities)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Rank nerve fibers in order from MOST to LEAST affected by local anesthetics (6 total)

A
  1. B - small, myelinated
  2. C - small, unmyelinated
  3. A-delta
  4. A-gamma
  5. A-beta
  6. A-alpha
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

3 major routes of administration

A
  1. Topical
  2. Injections
  3. IV regional
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Infiltration anesthesia

A

Injection directly into vicinity of peripheral nerve endings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Block anesthesia

Examples?

A

Injection directly into major nerve trunk (anesthetize region distal to site of injection)

Femoral nerve (distal to knee surgery), brachial plexus (UE or shoulder surgery)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Spinal anesthesia

A

Injection into CSF in lumbar space (anesthetize portion of body below the level)

17
Q

Epidural anesthesia

A

Injection or continuous infusion into epidural space (all regions of spinal cord)

18
Q

IV regional anesthesia

A

Short procedures (

19
Q

While epinephrine (alpha-1 agonists) may be used as a vasoconstrictor along w/ a local anesthetic to prolong the life of the drug, where should the epinephrine NOT be placed?

Where should it be placed WITH CAUTION?

A

Tissues supplied by end arteries (fingers, toes, ears, nose, penis)

Vasoconstriction could cause GANGRENE

Muscle tissues (Beta-2 agonist in muscle vasculature could cause vasodilation and systemic toxicity)

20
Q

Which local anesthetic does NOT need epinephrine?

A

Cocaine - potent vasoconstrictor (sympathomimetic)

21
Q

2 types of undesired effects from local anesthetic toxicity

A
  1. Systemic (CV or CNS depression)

2. Direct neurotoxicity (when given near major nerve trunks or spinal cord)

22
Q

A patient needs a large amount of a local anesthetic. What is indicated for protective measures?

A

A parenteral benzodiazepine (Diazepam or Midazolam) - to provide prophylaxis against CNS toxicity by raising seizure threshold

23
Q

Why might you need a benzo along with a local anesthetic?

A

Systemic anesthetic –> depression of cortical inhibitory pathways –> unopposed activity of excitatory pathways (seizure)

24
Q

Side effects of local anesthetics on CV system

A

Decreased heart conduction –> hypotension

Cocaine –> hypertension, arrhythmias, ischemia (via vasoconstriction)

25
Q

In addition to being an anesthetic, Lidocaine can be used as a _____

A

Anti-arrhythmic (slow down heart, let it re-set)

26
Q

If a patient is allergic to an ester type, what should you do?

A

Try an amide type (most likely allergic to other ester types)

27
Q

Benzocaine

A

Topical ONLY + anesthetic lubricant for tubes

28
Q

Bupivacaine

A

Long duration –> prolonged anesthesia

SENSORY over MOTOR

29
Q

Cocaine

A

Inhibition of catecholamine reuptake –> euphoria

Topical in upper respiratory tract

30
Q

Dibucaine

A

SKIN TOPICAL ONLY

31
Q

Lidocaine

A

Alternative if allergic to ester type
Faster, intenser, longer-lasting, more extensive than Procaine
Anti-arrhythmic

32
Q

Procaine

A

Lower potency, slower onset, shorter duration
INFILTRATION ANESTHESIA ONLY
Metabolite (PABA) inhibits sulfonamide antibiotics

Neurology 2 (22 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions