Pharmacology of Neuromuscular Blockers Flashcards Preview

IMSK Exam 2 > Pharmacology of Neuromuscular Blockers > Flashcards

Flashcards in Pharmacology of Neuromuscular Blockers Deck (24):
1

What does Ach hydrolyze into?

Acetate and choline

2

What are the three skeletal muscle relaxants acting at the neuromuscular junction used in therapy?

Competitive Neuromuscular Blockers
Depolarizing Neuromuscular Blockers
Botulinum Toxin

3

What are two types of competitive neuromuscular blockers?

Isoquinolones
Steroid-like

4

What is a common direct acting muscle relaxant?

Dantrolene

5

What is a common depolarizing neuromuscular blocker?

Succinylcholine

6

What are common Isoquinolones?

Atracurium
Cisatracurium
Doxacurium

7

What are common steroid-like skeletal muscle relaxants?

Pancuronium
Rocuronium
Vecuronium

8

What are two general chemical types of competitive neuromuscular blockers?

Aliphatic chain bis-quaternaries
Steroid-like chain bis-quaternaries

9

How do competitive neuromuscular blocking agents work?

Competitively inhibit acetylcholine from binding to the nicotinic receptor at the neuromuscular junction

10

Why do isoquinolines and steroid-like drugs not work well on muscarinic receptors?

Because they have 2 positive charges and fit poorly into a ganglionic nicotinic receptor

11

What happens when pancuromium or rocuronium are administered?

Pupil dilation
Tachycardia

12

What gives cisatracurium an advantage over atracurium?

Atracurium caused release of histamine whereas cisatracurium does not so there is no inflammation

13

How do non-depolarizing agents work?

Competitively inhibit acetylcholine binding to nicotinic receptors at the neuromuscular junction

14

What drug reverses the neuromuscular blockade?

Neostigmine (anticholinesterase)

15

How are steroid like NM blockers excreted?

In bile and renally

16

What is the order of susceptibility to blockade?

Small muscles of eye -> Muscles of hand, facial muscles -> Diaphragm and vocal cords

17

What is the byproduct of atracurium and cisatracurium hydrolysis?

Laudosine

18

What happens when succinylcholine is administered?

Initially there is a repeated activation of nicotinic receptors (muscle rigidity) followed by flaccid paralysis (muscle is not sensitive to depolarization anymore)

19

Succinylcholine initially stimulates autonomic ganglia causing what?

Bradycardia (prevented by atropine) and cardiac arrhythmia

20

What can Succinylcholine cause?

Hyperkalemia: cardiac arrest/arrhythmia

21

How does Dantrolene work?

Binds to ryanodine (RyR1) receptors in skeletal muscle not allowing calcium to be released from SR

22

Why does Dantrolene not work in smooth or cardiac muscle?

They have RyR2 not RyR1

23

What is Dantrolene used to treat?

malignant hyperthermia

24

How many types are botox are approved for use?

2 type A
1 type B