locals - apex Flashcards
rank the sensitivity of each nerve fiber type to the physiologic effect of LA in vivo. 1 is most sensitive, 4 is least sensitive
B fibers
C fibers
A delta
A alpha
conduction velocity is increased by ___ and a ___ fiber diameter
myelination, larger
block regression occurs in the opposite order of block onset. what does this mean?
the things that were blocked last are the first to recover
LA’s preferentially bind to the alpha subunit of the sodium channels in the ___ and __ states
active and inactive.
NOT resting
the voltage gated sodium channel contains __ alpha subunit and __ beta subunits
1, several
T/F LA’s increase threshold potential and decrease resting membrane potential.
FALSE La’s do not effect resting membrane potential or threshold potential.
when a critical number of sodim channels are blocked by LA, sodium is unable to enter the neuron in sufficient quantity. this means the neuron cant depolarize and the action potential cannot be propograted.
what form of the drug is required for it to gain entry inside the cell
uncharged base
T/F The conjugate acid binds to the intracellular portion of the sodium channel
TRUE
T/F Cross sensitivity is common between drugs in the amide class.
FALSE - extremely rare
what is the most common cause of toxic plasma concentrations?
inadvertent IV injection during regional
what is the most frequent symptom of LAST
seizure.
unless bupiviaince - cardiac arrest can occur before seizure
LAST - ACLS protocol what is the agent of choice
amiodarone.
epi rduces the effectiveness of lipid emulsion therapy.
for tx of ventricular arrhythmias, avoid lido and procainiamide. avoid vaso.
