Skeletal Muscle Relaxants

Question 1

what do skeletal muscle relaxants do?

Answer 1

Skeletal muscle relaxants will
influence the opening and closing of
the myoneural nicotinic receptors.

Question 2

how can you reverse non-depolarizing skeletal relaxants?

Answer 2

acetylcholinesterase inhibitor (AchEI)

Question 3

non-depolarizing skeletal relaxants are what kind of drug?

Answer 3

competitive inhibitors (non-depolarizing drugs can be out competed which is good

Question 4

what are neuromuscular blockers?

Answer 4

work at the NMJ to cause muscle paralysis

Question 5

because neuromuscular blockers work at the level of the NMJ how do they impact the CNS?

Answer 5

they do not impact the CNS due to the selectivity of the drugs to the myoneural nicotinic receptors

Question 6

what are spasmolytics and antispasmodics?

Answer 6

used to reduce muscle spacificty in varity of conditions such as TMD, bruxism and back pain

Question 7

how do spasmolytics and antispasmolytics work?

Answer 7

block at the level of the spinal cord

Question 8

where does dantrolene work?

Answer 8

directly on skeletal muscle

Question 9

D-tubocurarine is a what kind of drug?

Answer 9

competitive inhibitor that blocks at the myoneural nicotinic receptor

nondepolarizing drug (does not allow Na to gain entry to skeletal muscle)

Question 10

succinylcholine is a ____ drug

Answer 10

depolarizing

Question 11

how do you know if a drug is a part of the benzylisoquinoline drugs?

Answer 11

have a CUR in the name

Question 12

what do amino seriods have in the name?

Answer 12

-curonium

Question 13

Succinylcholine, a depolarizing drug. When compared to acetylcholine, it is….

Answer 13

• More potent and prolonged binding at nicotinic receptor.
• More resistant to degradation by acetylcholinesterases (AchE).

Question 14

how are NMB drugs given?

Answer 14

IV given when pt is undergoing anesthesia

Question 15

in benzylisoquinoline drugs what makes them more potent?

Answer 15

more methoxy groups = more potent

Question 16

Atracurium is no longer in widespread clinical use
because it can breakdown into a product called

Answer 16

laudanosine

Question 17

what is laudanosine?

Answer 17

slowly metabolized by the liver and can cross the blood-brain-barrier (BBB) which may cause seizures

(use cistatracurium instead)

Question 18

how are neuromuscular bocking drugs eliminated?

Answer 18

liver though biliary excretion

Question 19

The benzylisoquinolines are mainly eliminated through what mechanism?

Answer 19

enzymatic hydrolysis of ester bonds and elimination by the kidneys

Question 20

for NMB how is their clearance related to their action?

Answer 20

drug’s clearance is directly proportional to the drug’s duration of action.

Question 21

For succinylcholine, it does not get inactivated by acetylcholinesterase
within the synaptic cleft, but will be metabolized by ______ and ________ in the liver and plasma, respectively

Answer 21

butyrylcholinesterase
and pseudocholinestereasese

Question 22

how long is the duration of action for succinylcholine?

Answer 22

short, around 8 mins due to the rapid metabolism through cholinesterase

Question 23

if a pt has genetic deficiency of cholinesterase’s what must be avoided?

Answer 23

succinylcholine

Question 24

what is one risk that can occur with skeletal muscle relaxant?

Answer 24

if you use too much you can cause paralysis of the diaphragm

Question 25

which muscles get effected first my muscle blockers, which get reactivated first?

Answer 25

smaller muscles first to be blocked and last to recover from block when the anesthetic has been removed

Question 26

see notes sheet