Pharmacology Flashcards
what is in the safety plus system
syringe barrel with needle - single use
LA cartridges - sterile and single use
plunger
what is in a cartridge
2.2ml or 1.8ml anaesthetic agent vasoconstritor stabiliser/preservative isotonic carrier medium
what is an isotonic carrier medium
sterile saline solution
what is lidocaine
most commonly used
with adrenaline
utilycaine
what is mepivacaine
no vasoconstrictor in it
scandonest
what is prilocaine
with felypressin
citanest
produce oxytocin in body
what is the other prilocaine
prilocine plain
ctanest plainn
what is articain
with adrenaline
bartinest
what is the basic structure of LA
lipophilic head
intermediate chain (vary)
hydrophilic
what are the variable intermediate chains
ester (COO)
amide (NHCO)
what are some ester LA
procaine
benzocaine
what are some amide LA
lidocaine
prilocaine
mepivicine
articaine
how are ester LA usually applied
topical
how are amide LA usually applied
all injected
what is special about articaine
ester and amide links so broken down in body by both ester and amide enzymes
how to LA work
AP influence
Na channels
Membrane and receptor effects
what does LA do to AP’s
initial opening of sodium channels depolarisation
reversibly block sodium channels
what do LA do to mem and receptor
mem expansion
sp receptor theory
what is sp receptor theory
lipid soluble non charged
and
charged
why does a LA have t be lipid sol - non charged
to pass thro axon mem
why’d does an LA have to be charged
to bind to receptor in sodium channel
what does the dissociation of an LA dept on
pH of tissue
what ar LA properties
lipid sol
protein binding
vasodilator ability
why is LA lipid sol
high lipid sol partition coeff
rapid onset as passed through mem
why does LA protein binding
LA bound to protein provides a pool of available drug
high protein binding capability increased duration
what do most LA’s act as
vasodilators
what is an LA’s vasodilator ability
result in inc blood flow
more rapid removal of LA
imp vasoconstrictors added to injections
what is most common LA
gold standard
lidocaine
what is the alternative injection
prilocaine
what is mepivicaine used in mind of
least vasodilatory
what is important about bupivicaine
high protein binding therefore long-lasting
what is imp about articaine
relatively new
USP
dissusibilyt
what is the sequence of onset
C
A(gamma)
A(delta)
A(alpha)
how does absorption affect LA
uptake form site to bloodstream
loss of LA activity
wat does the absorption dept on
dose
vasoactivity of drug
vasoactiviity of tissue
vasodilator effect vs use of vasocons
unbound LA may enter
any organ
what are some highly perfused organs
brain
liver
kidneys
placenta
what are some LA effect on myocaridum
reduces excitability and cond
use acute cardiac are
what ate the effects of LA on peripheral vasc
vasodilation
if overdose hypotension
how does LA effect CNS
initial stimulation
then inc dose depression
what LA is metabolised in liver
primarily amidases imp liver disease
where is articaine metabolised
plasma
where is prilocaine metabolised
lungs and liver
- methaemoglobinaemia - interferes with oxygen carrying ability
