Muscle Relaxants and Anesthetic Drugs (Iszard)

Question 1

Neuromuscular blockers are divided into what 2 categories?

Answer 1

Non-depolarizing: Isoquinolines and Aminosteroids
Depolarizing: Succinylcholine

Question 2

What is the MOA of the non-depolarizing neuromuscular blockers?

Answer 2

competitive antagonist of nAChR; they are highly polar so parenterally administered; some antibiotics enhance their blockage activity

Question 3

What are the 4 isoquinoline non-depolarizing neuromuscular blockers?

Answer 3

“curiums”
Atracurium (least histamine release)
Cisatracurium (fewer side effects and can be given to patients with hepatic and renal impairment)
Doxacurium (contraindicated in renal failure)
Mivacurium

Question 4

“curiums” neuromuscular blockers

Answer 4

isoquinolines
Atracurium (least histamine release)
Cisatracurium (fewer side effects and can be given to patients with hepatic and renal impairment)
Doxacurium (contraindicated in renal failure)
Mivacurium

Question 5

Cisatracurium

Answer 5

isoquinoline non-depolarizing neuromuscular blocker; fewer side effects and can be given to patients with hepatic and renal impairment

Question 6

Which neuromuscular has agent fewer side effects and can be given to patients with hepatic and renal impairment?

Answer 6

Cisatracurium

Question 7

What are the 4 aminosteroids non-depolarizing neuromuscular blockers?

Answer 7

“curoniums”
Pancuronium (long acting; contraindicated in renal impairment)
Pipecuronium (long acting; contraindicated in renal and hepatic impairment)
Rocuronium (most rapid onset 60-120 secs; contraindicated in hepatic impairment)
Vercuronium (contraindicated in renal and hepatic impairment)

Question 8

Which aminosteroids non-depolarizing neuromuscular blocker has the quickest onset?

Answer 8

Rocuronium; most rapid onset 60-120 secs; contraindicated in hepatic impairment; only aminosteroid that is not eliminated by the kidneys

Question 9

Rocuronium

Answer 9

aminosteroids non-depolarizing neuromuscular blocker; most rapid onset 60-120 secs; contraindicated in hepatic impairment; only aminosteroid that is not eliminated by the kidneys

Question 10

What is the prototypte non-depolarizing neuromuscular blocker and why is it less favorable?

Answer 10

d-tubocurarine; very long duration of action; shorting-acting blockers are more favorable

Question 11

What is the one depolarizing neuromuscular blocker?

Answer 11

Succylcholine; contraindicated in malignant hyperthermia (do not use with Dantrolene); Black Box Warning of cardiac arrest

Question 12

Succycholine is contraindicated in what malignancy?

Answer 12

malignant hyperthermia

Question 13

Which aminosteroid non-depolarizing neuromuscular blocker is a good alternative to succinylcholine?

Answer 13

Rocuronium; most rapid onset 60-120 secs; contraindicated in hepatic impairment; only aminosteroid that is not eliminated by the kidneys

Question 14

What are the 3 subgroups of acetylcholinesterase Inhibitors?

Answer 14

1. alcohols - reversible
2. carbonic acid esters - reversible (neostigmine and pyridostigmine)
3. organophosphates - IRREVERSIBLE (ecothiophate)

Question 15

organophosphates

Answer 15

an irreversible acetylcholinesterase Inhibitor; ecothiophate “nerve gas”
can try to treat with regeneration of AChE (Pralidoxime)

Question 16

Which drug is used for the regeneration of AChE

Answer 16

Pralidoxime

Question 17

Pralidoxime

Answer 17

regeneration of AChE; used in cholinergic crisis along with atropine

Question 18

Which drugs are indicated for myasthenia gravis?

Answer 18

reversible acetylcholinesterase inhibitors that do not cross the BBB; increases available ACh; neostigmine and pyridostigmine

Question 19

Drug used to reverse neuromuscular blockage in drug induced paralysis?

Answer 19

reversible acetylcholinesterase inhibitor neostigmine (carbonic acid ester)

Question 20

What are the 9 centrally acting spasmolytics?

Answer 20

1. baclofen - GABAb agonist
2. Carisoprodol - schedule IV controlled substance; metabolized by CYP2C19
3. Chlorzoxazone - acts on spinal cord
4. Cyclobenzaprine - causes significant sedation; metabolized by CYP450s
5. Diazepam - schedule IV controlled substance
6. Metaxalone - interrupts spasm-pain-spasm cycle
7. Methocarbamol - causes general CNS depression
8. Orphenadrine
9. Tizanidine

Question 21

Which centrally acting spasmolytic interrupts spasm-pain-spasm cycle?

Answer 21

Metaxalone

Question 22

What are the two scheduled IV controlled centrally acting spasmolytics?

Answer 22

Carisoprodol and Diazepam

Question 23

What are the two centrally acting spasmolytics metabolized by CYP proteins?

Answer 23

Carisoprodol and Cyclobenzaprine

Question 24

What are the 2 non-centrally acting spasmolytics?

Answer 24

1. Dantrolene (do not use with Succylcholine); causes inhibition of RyR receptors on skeletal muscles
2. Botulism toxin - cleaves SNARE proteins preventing release of ACh

Question 25

What are the 5 ester local anesthetics?

Answer 25

“caines”
Cocaine
Procaine
Benzocaine
Chloroprocaine
Tetracaine

Question 26

What is the difference between amide and ester local anesthetics?

Answer 26

amides are chemically stable in vivo and esters are rapidly hydrolyzed by proteins in vivo

Question 27

What is the general route of administration of general anesthetics?

Answer 27

inhalation or IV injection

Question 28

What are the 4 IV injected general anesthetics?

Answer 28

1. propofol (adults; general anesthesia)
2. Thiopental
3. Etomidate (general anesthesia)
4. ketamine (pediatrics)

Question 29

What are the 6 inhaled general anesthetics?

Answer 29

“fluranes”
1. Desflurane
2. Enflurane
3. Halothane “ane”
4. Isoflurane
5. N2O
6. Sevoflurane

Question 30

Which general anesthetic is commonly used for short out-patient surgeries or procedures?

Answer 30

propofol (adults; general anesthesia)

Question 31

What is the most commonly used amide local anesthetic?

Answer 31

Lidocaine