NMG, Reversal Agents, Antimuscarinic

Question 1

What are the mechanisms of action of NMBs?

Answer 1

• depolarizing muscle relaxants act as ACh receptor agonists then antagonists
• nondepolarizing muscle relaxants function as competitive antagonists

Question 2

What are the 4 non-depolarizing, competitive muscle relaxants?

Answer 2

Pancuronium
Vecuronium
Atracurium
Rocuronium

Question 3

What is phase I block of sux?

Answer 3

Depolarizing phase

Question 4

What is phase II of Sux?

Answer 4

Desensitizing phase

-block converts from depolarizing to nondepolarizing block (occur with larger doses or prolonged infusion

Question 5

What is surmountable antagonist?

Answer 5

Produce parallel rightward shifts of agonist dose–response curves with no alteration of the maximal response (can be overcome)

Question 6

Is Sux susceptible to acetylcholinesterase?

Answer 6

NO

Question 7

What are the 4 things that impact Sux duration of action?

Answer 7

Hypothermia
Low enzyme
Genetic
Clinical pearl

Question 8

How to manage hyperkalemia for Sux?

Answer 8

Insulin + glucose to prevent hypoglycemia
Calcium gluconate to stabilize cardiac rhythm
Reduce K level with dialysis

Question 9

When to NOT use Sux?

Answer 9

Underlying NM disease
Risk of MH 
History of allergy to sux
Homozygous for atypical plasma cholinesterase 
High K concentration

Question 10

Plasma cholinesterase metabolizes which ND agent?

Answer 10

Mivacurium

Question 11

Nonezympatic metabolizes which NG agent?

Answer 11

Atracurium, cisatracurium

Question 12

Hepatic metabolizes which NG agent?

Answer 12

Vecuronium

Rocuronium

Question 13

Renal metabolizes which NG agent?

Answer 13

Pancuronium

Doxacurium

Question 14

Which NG agent has an intermediate acting?

Answer 14

Atracurium
Rocuronium
Vecuronium

Question 15

Which NG agent has long acting?

Answer 15

Pancuronium

Question 16

Which NG agents cause histamine release?

Answer 16

Atracurium

Mivacurium

Question 17

Which NG agent have a vagal blockade?

Answer 17

Rocuronium

Pancuronium

Question 18

What does atracurium use for metabolite?

Answer 18

Laudanosine

Question 19

Key things about cisatracurium (5)

Answer 19

Intermed onset and duration 
Does not affect histamine release 
Lacks HR and BP effects 
Laudanosine metabolite 
Sorted in refrigerator because loses potency at room temp

Question 20

Key things about pancuronium (5)

Answer 20

Intermed onset and duration 
Metabolized by liver 
Elimination by kidney 
Stored in refrigerator, stable at room temp for 6months 
Hypertension and tachycardia

Question 21

Key things about vecuronium (3)

Answer 21

Intermed onset and duration
Stable BP and HR
Neonates

Question 22

Key things about rocuronium (4)

Answer 22

Faster (but longer than Sux) onset and intermed duration
No metabolism
Eliminated by liver and kidney
Less potent so requires bigger doses

Question 23

Monitoring of NM block?

Answer 23

Peripheral nerve stimulator

Question 24

When does single twitch stimulation completely disappear?

Answer 24

90-95% receptors occupied

Question 25

Train of four monitoring

Answer 25

1st 90-98% block 2nd 85-90% block 3rd 80-85% block 4th 75% block

Question 26

Recovery TOF ratio:

Answer 26

.9

Question 27

How does cholinesterase inhibitors work?

Answer 27

Increase ACh activity by increasing duration of time present to act at receptors

Question 28

What are the 3 types of AChE inhibitors?

Answer 28

``` Reversible 1 alcohol structure - edrophonium 2 carbamic acid esters (carbamates) - Neostigmine Irreversible 3 organophosphates ```

Question 29

Mechanism for both AChE inhibitors?

Answer 29

Non depolarizing, competitive | Compete with Ach to bind with nicotinic receptor of motor end plate

Question 30

Neostigmine onset and duration

Answer 30

5 - 10 min | 1 hour

Question 31

Pyridostigmine onset and duration

Answer 31

10-15min | >2hrs

Question 32

Edrophonium onset and duration

Answer 32

1-2min | 1hr or less

Question 33

Mechanism of action for Sugammadex

Answer 33

Encapsulates or chelates the free molecule form of rocuronium (maybe vecuronium) to make soluble in plasma

Question 34

Sugammadex metabolism and elimination

Answer 34

No metabolites and really eliminated

Question 35

How long do you have to wait to redose Sugammadex with rocuronium and vecuronium?

Answer 35

24hrs

Question 36

What kind of effect does anti muscarinic have on body?

Answer 36

Inhibit Parasympathetic nervous system

Question 37

What is atropine onset and duration?

Answer 37

Faster onset | Shorter duration

Question 38

What is glycopyrrolate onset and duration?

Answer 38

Slower onset | Longer duration