local anesthetic techniques (Garcia) Flashcards
1
Q
Amide characteristics
A
- stable in solution
- enzymatic degradation (liver)
- no p-Aminobenzoic acid metabolite
2
Q
Esters characteristics
A
- unstable in solution
- metabolized in plasma
- cholinesterase enzymes
- p-Aminobenzoic acid metabolite
- allergic reactions
3
Q
Commonly used amides
A
- lidocaine
- bupivicaine
- mepivacaine
- ropivacine
- EMLA
4
Q
Commonly used esters
A
- cocaine
- benzocaine
- procaine
- tetracaine
5
Q
Benzocaine can cause
A
hemolysis
6
Q
Onset of local affected by
A
- liphophilicity (higher = faster)
- pKa
- Concentration
- Dose + volume
- prox to nerve
- type of nerve
7
Q
Any acidic environment (infection/inflammation)
A
will make topical inneffective
-block nerve instead
8
Q
duration of locals affected by
A
- vascular effect
- tissue blood flow
- vasoconstrictor
- dose
- affinity to Na receptor
- lipophilicity
9
Q
Mechanism of action
A
- Na channel blocker
- acts on neuron axon
- affects depolarization
- dec conduction
- sensory and motor
10
Q
factor affecting action of locals
A
- pH/pKa
- proximity
- dose
- volume
- spread: nodes of ranvier
11
Q
Neurologic toxicity
A
- tremor
- nervousness
- seizures
- CC/CNS ratio
12
Q
cardiovascular toxicity
A
- bradycardia
- sinus arrest
- fibrillation
- bupivacaine
13
Q
topical use
A
- larynx: cats have sensitive larynxes
- splash block
- mucous membranes
- EMLA
14
Q
infiltration
A
- injection at surgical site
- blockage of nociceptive input
- dose
*requires a larger volume, more likely for toxicity
15
Q
Femoral compartmental block
A
- substitute epidural
- psoas major
- L4-L5
- technique
- less invasive than epidural
