This site is 100% ad supported. Please add an exception to adblock for this site.

Block 1: Anesthetics- Local

Terms

undefined, object
copy deck
3 parts of LA
lipophilic group- aromatic ring
intermediate chain- ester or amide
hydrophilic group- secondary or tertiary amine
increasing _____ increases the anesthetic potency and duration but also increases side effects
hydrophobicity
more likely to cause allergic reax
esters (cocaine and procaine) from PABA metabolites
topical anesthesia in URT
cocaine
prototype ester
procaine
inhibition of catecholamine uptake
cocaine
infiltration anesthesia and diagnostic nerve blocks
procaine
inhibit action of sulfonamides
procaine
aka novocain
procaine
prototype amide
lidocaine
antiarrhythmic agent
lidocaine
metabolism in liver and plasma
cocaine
metabolism by pseudocholinesterase
procaine
metabolism by liver CYP450
lidocaine
_________ form is required to cross the membrane
unprotonated
______ form is most active at receptor site
protonated, charged
LAs are typically strong/weak acid/base
weak bases, pka 8-9
Do LAs change resting membrane potential
no
the degree of block depends on
voltage and frequency
puffer fish
tetrodotoxin
dinoflagellates (red tide)
saxitoxin
tetrodotoxin and saxitoxin...
reversibly block sodium channel like LAs, but they do it from the outside
critical length
shorter blocks first
firing frequency
sensory if faster - blocked first
fiber position
outer fiber blocked first
susceptibility
C > Ad > Ag > Ab > Aa
sensation lost
pain-> temp-> touch-> deep press-> motor
sensations regained
opposite of
pain, temp, touch, deep pressure, motor
epinephrine and clonidine
may enhance spinal anesthesia by acting at A2 ADRENERGIC RECEPTORS to
dec. firing of SENSORY NEURONS
and
inhibit release of SUBSTANCE P
LA's...(decrease/increase)
___ myocardial electrical excitability
___ conduction rate
___ blood pressure

exception...
decrease
decrease
decrease

exception = cocaine --> increases heart rate and blood pressure

Deck Info

30

permalink