APEX Neuromuscular Blockers

Question 1

Which nicotinic subunits must be occupied to open the receptor at the motor endplate?

Answer 1

alpha and alpha

Question 2

What breaks down ACH?

Answer 2

acetylcholinesterases
via receptors just near NM receptor
Acetyl goes into axon
choline diffuses away

Question 3

nN vs nM

Answer 3

nN is prejunctional on axon terminal
nM is postjuncitonal on the motor plate with 5 units

Question 4

What happens to electrolytes when postsynaptic junciton on motor plate is open?

Answer 4

K out
CA, NA, in
CL nothing

Question 5

When is Succ contraindicated?

Answer 5

HyperK
Burns
Trauma
Spinal chord injury
CVA
Sepsis

Question 6

What is fade

Answer 6

Antagonism of Nn presynaptic receptors
Happens with each attempt to squeeze a muscle,
Less and less ach is available dt blocking of the releasing receptor

Question 7

Which NMB cause fade

Answer 7

Non depolarizing, not depolarizing
Succ agonizes Nn receptor unlike NDNMB

Question 8

The role of CA in presynaptic axon

Answer 8

Influx
depolarize
release ACH

Question 9

The role of the presynaptic Nn receptor in the synaptic cleft

Answer 9

Once ach binds,
stimulates the mobilization of ACH vesicles to get ready to fire

Question 10

Phase 1 block

Answer 10

succ binds to Nn, releases ample ach into cleft

Question 11

phase 2 block

Answer 11

ndnmb binds to Nn, causing fade
OR
high dose succ (>7-10mg/kg or over 30min exposure)
cant distinguish