Neuromuscular Relaxants

Question 1

Succinylcholine mechanism of action

Answer 1

Depolarization blockade of muscle nicotinic receptors

Question 2

Succinylcholine indication

Answer 2

Tracheal intubation

Electroconvulsive therapy

Question 3

Effect of cholinesterase inhibitors on succinylcholine blockade within 4-8 min

Answer 3

Augmented blockade

Question 4

Side effects of succinylcholine

Answer 4

Non-analgesic
Apnea
Muscle pain
Arrhythmia, hypertension and bradycardia
Hyperkalemia
Malignant hyperthermia

Question 5

Pancuronium mechanism of action

Answer 5

Non-depolarizing blockade of muscle nicotinic receptors

Question 6

Pancuronium indication

Answer 6

Adjuvant in surgical anesthesia
Abdominal wall relaxtion
Orthopedic procedures

Question 7

D-tubocurarine mechanism of action

Answer 7

Non-depolarizing blockade of muscle nicotinic receptors

Question 8

D-tubocurarine indication

Answer 8

Prototype drug

Only used in lethal injection

Question 9

Rocuronium mechanism of action

Answer 9

Non-depolarizing blockade of muscle nicotinic receptors

Question 10

Rocuronium indication

Answer 10

Intubation

Muscle relaxation during surgery or ventilation

Question 11

Mivacurium mechanism of action

Answer 11

Non-depolarizing blockade of muscle nicotinic receptors

Question 12

Mivacurium indication

Answer 12

Intubation

Muscle relaxation during surgery or ventilation in patients with RENAL FAILURE

Question 13

Vecuronium mechanism of action

Answer 13

Non-depolarizing blockade of muscle nicotinic receptors

Question 14

Vecuronium indication

Answer 14

Adjuvant in surgical anesthesia

Abdominal wall relaxation, orthopedic procedures

Question 15

Which non-depolarizing NMJ blockade drug would you use in a patient with liver failure?

Answer 15

Pancurium, because it is primarily eliminated by the kidney

Question 16

Baclofen mechanism of action

Answer 16

GABA B agonist

Inhibits neurotransmitter release from skeletal muscle sensory afferent

Question 17

Baclofen indication

Answer 17

Muscle spasticity associated with MS or spinal cord injury

Question 18

Baclofen side effects

Answer 18

Drowsiness

Question 19

Diazepam mechanism of action

Answer 19

Benzodiazepine receptor agonist

“GABA mediated presynaptic inhibition”

Question 20

Diazepam indication

Answer 20

Muscle spasm due to local injury

Muscle spasticity due to loss of inhibitory input (cerebral palsy)

Question 21

Tizanidine mechanism of action

Answer 21

centrally acting α2 agonist

“TWOz-α-nidine”

Question 22

Tizanidine indication

Answer 22

Muscle spasticity due to spinal cord injury or MS

Question 23

Side effect of benzodiazepines

Answer 23

Drowsiness

Question 24

Tizanidine side effects

Answer 24

Drowsiness, hypotension

Question 25

Dantrolene mechanism of action

Answer 25

Uncouples excitation contraction of skeletal muscle by blocking ryanodine receptors

Question 26

Dantrolene indication

Answer 26

Muscle spasm

Malignant hyperthermia

Question 27

Dantrolene side effects

Answer 27

Muscle weakness

Sedation

Question 28

What are the two classes of neuromuscular blockers?

Answer 28

1) Non-depolarizing agents (curare type)

2) Depolarizing agents (succinylcholine)

Question 29

How do you reverse the effect of non-depolarizing muscle relaxants?

Answer 29

Administer neostigmine (AChE inhibitor to increase [ACh] in synapses) and Glycopyrrolate (to minimize the muscarinic effects of neostigmine)