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RUSVM Anesthesiology-Spring '18 > NMBD > Flashcards

Flashcards in NMBD Deck (24)
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1
Q

What is the definition of NMBD?

A

Reversible occupation of nicotinic cholinergic receptors by drugs that prevent neuromuscular transmission by restricting Ach access to receptor sites

2
Q

NMBD result in what?

A

complete paralysis of striated muscles-most effective way of relaxing muscles

3
Q

T/F: Animals can retain consciousness when on NMBD?

A

TRUE

4
Q

T/F: Respiration ceases when on NMBD due to the effect the drugs have on the diaphragm.

A

TRUE-Make sure to ensure artificial ventilator support

5
Q

When are NMBD drugs used?

A

Microscopic ophthalmic sx, thoracic sx and diaphragm hernia repair, orthopedic sx

6
Q

What is the MOA of NMBD drugs?

A

Reversibly occupy postsynaptic nicotinic cholinceptors and prevent neuromuscular transmission by restricting Ach access to these sites

7
Q

How does a muscle contraction occur?

A

AP arrives at pre-junctional alpha motor neuron ending –> nerve terminal becomes depolarized –> conversion of ATP to cAMP results in Ca influx into nerve terminal which further releases Ach into synaptic cleft –> Ach crosses synapse to interact with post-junctional nicotinic receptors resulting in muscle cell action potential and muscle contraction –> Ach rapidly metabolized by acetylcholinesterase in synaptic cleft

8
Q

What is an example of depolarizing (non-competitive) NMBD?

A

Succinylcholine. Depolarize postsynaptic membrane until fatigued leading to muscle paralysis

9
Q

What is an example of non-depolarizing (competitive) NMBD?

A

Atracurium, rocuronium, vecuronium, rapacurium. Block interaction of Ach with receptors

10
Q

What is the order in which NMBD act on specific muscle groups?

A

Face/muscles of expression –> neck muscles –>diaphragm–> distal limbs –> proximal limbs –>abdominal muscles –> intercostal muscles

11
Q

T/F: NMBD are water soluble drugs.

A

TRUE. THey do NOT cross the BBB

12
Q

What drugs potentiate the effects of NMBD?

A

Inhalational anesthetic drugs, injectable anesthetic drugs, aminoglycosides, antiarrhythmic drugs, diuretics, Mg

13
Q

What are the pros and cons to depolarizing NMBD?

A

Pros: rapid onset, short duration
Cons: muscle fasiculations, muscle contractions, malignant hyperthermia, cardiac arrhythmias, histamine release

14
Q

What are the two benzylisoquinolinium non-depolarizing NMBD drugs?

A

Atracurium and cis-atracurium

15
Q

T/F: Atracurium has slow metabolism due to non-enzymatic degradation which is dependent on pH and temperature

A

FALSE. Fast metabolism

16
Q

What is the first NMBD that is free of CV effects?

A

Vecuronium

17
Q

What is the shortest and longes acting non-depolarizing NMBD?

A

Long acting: pancuronium (>30 minutes)

Short acting: Rapacuronium (<10 minutes)

18
Q

What nerves do you place a peripheral nerve stimulator on in SA vs. equine?

A

SA: peroneal and ulna n.
Horse: facial n. and superficial peroneal n.

19
Q

What are the two nerve stimulation patterns?

A

Single twitch and Train of four

20
Q

What rate does single twitch stimulate at?

A

0.1-1 Hz

21
Q

What is the degree of relaxation for single twitch stimuli?

A

Degree of relaxation=post NMBD elicited response/pre-relaxant response

22
Q

What is the degree of relaxation for train of four stimuli?

A

Degree of relaxation=ratio of intensity of twitch 4/twitch 1

23
Q

How are NMBD drugs antagonized?

A

Anti-cholinesterases (edrophonium and neostigmine)

24
Q

Aminosteroid NMBD can be antagonized with what?

A

Sugammadex