NMB: Part 1 Flashcards Preview

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Flashcards in NMB: Part 1 Deck (65)
1

what are the uses of NMB?

Facilitate tracheal intubation
IMprove surgical working conditions
Mechanical ventilation of lungs
laryngospasm

2

In terms of ED95, how much NMB should be given for intubation?

2xED95

3

How do volatile anesthetics affect NMBD?

Decrease ED95

4

NMBD effects __________(small/large), ________ (rapidly moving, Slowly moving) muscles first

small, rapidly moving muscles are affected first

5

ONset of block depends on _______ type and _____receptor density

Fiber, ACh

6

Which is more sensitive to NMBD, fast or slow fibers?

fast

7

Obicularis occuli is useful for predicting paralysis of _____________, while the adductor pollicis is more reflective of ___________.

vocal cords, diaphragm

8

Are NMBD lipid soluble? What is the volume of distribution?

Highly ionized therefore limited lipid solubility with limited volume of distribution

9

What effects do NMBD have on CNS, renal and fetus?

none, since they are ionized, they cant cross lipid membranes

10

How does age affect NMBD clearance?

Elderly pts have less blood flow to the liver and therefore clear NMBD more slowly. Volatile anesthetics also decrease bf and will slow clearance

11

Benzylisoquinolinium drugs end in ________ and aminosteroid drug names end in ___________.

-curium, -ronium

12

how do NMBD bind? at the neuromuscular junction block to interrupt transmission of nerve impulses?

the + nitrogen binds to the - alpha subunit of the receptor

13

besides the neuromuscular junction, where else might NMBD have effects?

cardiac muscarinic receptors
autonomic ganglia nicotinic receptors

14

Acetylcholine is stored in ________ aka ________

packets, quanta

15

Which subunit of the nicotinic receptor does succinylcholine attach to?

alpha

16

What is the dose of sux?

1-2 mg/kg

17

what is onset and duration of sux?

30-60s, 3-5 min

18

How is sux metabolized?

plasma cholinesterase

19

Extremely high doses of sux may _________ duration.

increase

20

what does the TOF look like in phase I blockade?

4 twitches that may be decresed, but have no fade
TOF 4 ration >0.7
Decreased amplitude during tetany
NO posttetanic facilitation

21

What happens when you give anticholinesterase to reverse sux?

Enhances block, since cholinesterase breaks down sux too.

22

What does a phase 2 blockade look like?

Resembles non depolarizing NMB
has fade and posttetanic potentiation

23

How do repeated doses of sux manifest?

tachyphylaxis

24

Is the transition from phase I to phase II fast or slow?

abrupt

25

What drugs may decrease plasma cholinesterase activity?

Anticholinesterases
Metoclpramide

26

what is the normal dibucaine number?

80

27

What are examples of patients that are susceptible to hyperkalemia from sux?

Burns
Skeletal muscle trauma
Intrabdominal infection
Muscle atrophy
Muscular dystrophy
T4-T6 lesions

28

How does sux affect ICP and IOP?

increases both

29

Why should you avoid sux for patients with small bowel obstruction, pyloric stenosis, or bleeding varices?

Sux causes increase intragastric pressure

30

What are the characteristics of NDPNMB?

Decresed single twitch
Fade with tetanus
TOF <0.7
Post tetanic potentiation
Antagonized by anticholinesterase

31

What is the mechanism of NDPNMB?

Compet with ACh at alpha subunits at postjunctioal nicotinic receptor. Also has some action at pre-junctional receptor

32

What effect does Sux have on HR?

dysrythmias
bradycardia from sux mimicing ACh at cardiac muscarinic cholinergic receptors, especially if a second dose is given 5 minutes after first
(Tachycardia and increased BP may occur if sux mimic ACh at autonomic nervous system ganglia)

33

Side effects from NDPNMB are ______. (rare/common)

rare

34

Which NMB is associated with histamine release?

atricurium

35

Which NMB is associated with tachycardia?

pancuronium--vagolytic

36

Pancuronium has a _____ autonomic margin of safety.

low

37

Name drugs that enhanece NDNMB (6)

Volatile anesthetics
Amino glycosides
Local anesthetics
Anti dysrhythmics
Diuretics
Ganglionic blockers (trimethaphan)

38

How do phenytoin and other seizure meds affect NMB?

Increased metabolism, may need to use a drip

39

Hypokalemia and hypothermia _________ blockade

prolong

40

How do thermal injury/burns affect blockade (nondepolarizing)

resistant

41

How does magnesium affect NM blockade?

Magnesium inhibits ACh release so therefore potentiates block

42

What happens if you mix a steroid relaxant with a Isoquinolone relaxant?

they are synergistic. YOu can get a real long block

43

What if you give roc before the sux has worn off?

synergistic. always check twitches

44

What is the onset and duration of pancuronium?

3-5 minutes, 60-90 minutes

45

What are the CV effects of pancuronium?

Increased HR, MAP and CO

46

The dose for pancuronium is the same as_______

vecuronium

47

Clearance of pancuronium is decreased up to ___% with renal failure

50

48

What is the onset and duration of Atracurium?

3-5 minutes, 20-35 minutes

49

How is atracurium cleared?

Hoffman elimination and ester hydolysis
not dependent on kidney or liver

50

What are the side effects of atracurium

Histamine release
-may lead to bronchoconstriction, should avoid in asthmatics
Cardiovascular effects-vasodilation

51

How does metabolism of atracurium differ in peds vs elderly?

No different since it is not dependent on liver BF

52

What is the metabolite of atracurium and what effect does it have?

Laudanosine--CNS stimulant--probably not clinically significant

53

What is the dose of cisatracurium?

0.1-0.15 mg/kg
infusion 1-2 ug/kg/min

54

Does cisatracurium cause histamine release?

No

55

How is Cisatracurium metabolized?

Hoffman degradation

56

How does pH and temperature affect hoffman degradation?

INcreased pH increases elimination
decreased body temperature decreases elimination

57

What is the intra op dose of vecuronium?

0.01mg/kg q 15-20 min for maintenance
INfusion: 1-2 mcg/kg/min

58

How is vecuronium metabolized and cleared?

predominantly metablolized and excreted by liver.

59

What is the RSI and maintenance dose for roc?

0.6-1.2 mg/kg
0.1 mg/kg maintenance
5-12mcg/kg/min infusion

60

How is roc metabolized and cleared?

No metabolism
All is cleared in bile and kidneys

61

Mivacurium is a _________-acting NMBD that is no longer in production

short

62

How is mivacurium cleared?

plasma cholinesterase

63

Which NMBD would you use for renal or severe hepatic failure?

Mivacurium, cisatracurium, atracurium

64

Which NMDB would be the best choice for long cases?

Pancuronium

65

Which NMDB would you choose for plasmacholinesterase deficient cases?

roc/vec