Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology 680 > Pathophysiologic Implications - NMB > Flashcards

Pathophysiologic Implications - NMB Flashcards

1
Q

What does it mean when you have RESISTANCE to a nondepolarizing NMB?

A

you will have to give more of the medication to get the response wanted

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what does it mean when you are sensitive to a NMB?

A

your duration will last longer if you give the normal dose, so give less

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What does phenytoin (dilantin) due to a nondepolarizing NMB?

A
  • causes shorter duration (resistance)
  • Because of
    • decreased activity of AChE
    • induced cytochrome p450 in the liver (metabolism)
    • increased number of ACh sites
  • can change duration even if you give it intraoperatively!!
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

There are 3 meds mentioned that phenytion causes a decreased duration of. What are the meds and the percentages associated?

A

Rocuronium 20%
Vecuronium 37%
Pancuronium 40%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

These meds are given to myesthenia gravis patients (immunosuppressed pt, asthma) to improve neuromuscular function; chronic use has been reported to cause ____ to _____ NMB like vecuronium

A

resistance, steroidal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

these two meds inhibit phosphodiesterase which increases cAMP needed to synthesize and release ACh which leads to more ACh

A
  • aminophylline and theophylline

- a greater dose is needed to compete with the increase in ACh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

This med in large doses, 1-4 mg/kg, inhibits phosphodiesterase which increases cAMP which makes ACh more available

A

furosemide

-increase the dose due to increased resitance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

resistance begins 10 days after injury, peaks at 40, and declines after 60 days (463 days is longest)

A

burn injuries

  • would not give depolarizing bc K
  • due to a decreased sensitivity of the postjunctional receptors to either ACh or nondepolarizing NMB, basically nondepolarizers will be chewed up
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Type of patients with increased extrajunctional receptors?

A

MS, hemiplegic limb, CVA, prolonged immobilization, massive trauma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why is the paralyzed limb of a CVA patient more resistant to NMB?

A

more extrajunctional cholinergic receptors due to denervation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Main reason not to give MS patients NMB?

A

they are unpredictable! Do not know if pt are in remission periods.
definitely not going to give SCh bc of hyperkalemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

this causes increased resistance due to decreasing the resting potential of the membrane which increases the positivity of the cell

A

chronic hyperkalemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

does chronic hyperkalemia increase or decrease sensitivity to SCh?

A

increases sensitivity because the resting membrane potential is more positive, which is closer to depolarization and closer to an action potential

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q 
pharmacologic 
   -corticosteroids
   -amino/theophylline
   -furosemide 
burn injuries
increased extrajunctional receptors
chronic hyperkalemia
A

factors associated with resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

these decrease the skeletal muscle tone and decrease the sensitivity of muscle membranes to depolarizations lower than the ED95; have the greatest impact on long acting NMB (pancuronium)

A

volatile anesthetics

increase sensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

these interfere with the release of ACh from the prejunctional receptors, block ion channels, and directly depress skeletal muscle tone

A

local anesthetics

increase sensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

these cause a magnesium type effect to decrease release of ACh to make reversal unreliable (can give Ca)

A

antibiotics

increase sensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

aminoglycosides - gentamicin, neomycin, streptomycin, kanamycin, amikacin, tobramycin

A

antibiotics that increase the sensitivity of nmb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

antibiotics that have NO effect on nmb

A

penicillins, cephalosporins, erythromycin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

when given to a patient who is recovering from a nondepolarizing nmb, the block is potentiated by the blockage of the prejunctional release of ACh

A

lidocaine

increased sensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

potentiates nondepolarizing nmb and SCh

A

quinidine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

this med has a variable effect on nondepolarizing and prolonged onset and duration of depolarizing nmb

A

lithium

increased sensitivity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what production is decreased when giving <1mg/kg of lasix per day resulting in increased sensitivity to nmb

A

lasix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

this med increases the sensitivity of nmb (specifically atracurium and vecuronium, and is used for renal replacement pt, rheumatoid, and psoriasis pt

A

cyclosporine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

this med reduces the dose required due to membrane desensitization causing enhanced, but not prolonged, blockade by nondepolarizing nmb

A

succinylcholine

26
Q

if you have a combination of nondepolarizing nmb - you will see a ___ effect

A

synergistic

-usually combo of drugs from different classes

27
Q

the usual site of action is on the slow channels, not fast channels like the postjunctional receptors so unpredictable effects have been reported

A

calcium channel blockers

28
Q

acute admin of this med may potentiate nondepolarizing nmb

-the combo of the two types of meds could cause critical illness myopathy

A

hydrocortisone

29
Q

this med is given as a stress dose to people on chronic steroids

A

hydrocortisone

30
Q

these meds can decrease sensitivity of the muscle membrane to cause relaxation of its own and potentiate nondepolarzing nmb

A

trimethaphan and hexamethonium

31
Q

these meds inhibit plasma cholinesterase activity to cause prolongation of depolarizing block

A

trimethaphan and hexamethonium

ganglionic blockers

32
Q

prolongs duration by slowing clearance via hepatic enzymes, renal pathways, hofmann elimination, and ester hydrolysis

A

hypothermia

33
Q 
antihypertensives
hydrocortisone
ca channel blockers
SCh
cyclosporine
lasix
lithium
lidocaine
quinidine
antibiotics
volatile and local anesthetics
A

pharmacologic factors associated with increased sensitivity

34
Q

increases membrane potential (hyperpolarization) and increases sensitivity to nondepolarizing nmb (resistant to SCh)

A

acute hypokalemia

35
Q

decreased release of ACh from prejunctional receptors which causes an enhanced block (think pregnant women and preterm labor)

A

hypermagnesium

36
Q

___ causes decreased volume of distribution of nmb so more drug reaches the receptors

A

dehydration, seen with hypernatremia

37
Q

difference in muscle mass from men cause __ block in women with similar mg/kg
(really not clinically relevant)

A

greater

38
Q

chronic autoimmune disorder caused by a decrease in functioning acetylcholine receptors at the NMJ by antibodies

A

myasthenia gravis

39
Q

treatment of myasthenia gravis includes anticholinesterases and immunosuppressive drugs. More ACh is available which causes

A

resistance to nondepolarizers and sensitivity to SCh

40
Q

what muscles are first to show fatigue, weakness in undiagnosed myasthenia gravis

A

ocular, pharyngeal, and laryngeal muscles

41
Q

with these patients it is very important to get a baseline TOF and reduce the dose by 1/2 or 1/3

A

myasthenia gravis because they may become weak with even 1/10 of the normal intubating dose!!
prob shouldn’t use nmb

42
Q

seen with oat cell carcinoma of the lung; autoimmune disease where presynaptic calcium channels are destroyed by antibodies

A

myasthenic syndrome - eaton lambert

43
Q

sensitive to both nondepolarizing and SCh

A

myasthenic syndrome - eaton lambert

44
Q

normal or possible prolonged effect of nondepolarizing nmb when muscle weakness, atrophy, exists

A

muscular dystrophy

45
Q

SCh causes prolonged contraction but nondepolarizing blockades have a normal response

A

myotonia dysrophica

46
Q

a degenerative disease of motor ganglia in the anterior horn of the spinal cord and spinal pyramidal tracts that causes skeletal muscle atrophy and weakness

A

amyotrophic lateral sclerosis

47
Q

what does als cause

A

prolonged response to nondepolarizing nmb (sensitivity) and hyperkalemia with SCh

48
Q

have a different volume of distribution which makes the dose less concentrated
“water babies”

A

pediatric population

49
Q

vecuronium onset is quicker in infants and children due to ____ times

A

faster circulation

50
Q

infants and neonates have prolonged recovery to vecuronium because .. while children have a faster recovery

A

liver function isnt as good

51
Q

neonates require __ lower dose by weight due to increased sensitivity when given atracurium

A

25%

52
Q

special considerations for the elderly, dried up little old people

A
  • decreased total body fluid, fat, lean muscle
  • decreased plasma protein, CO, kidney/liver function
  • priming technique causes rapid desat
  • basically more free drugs floating around
53
Q

even though this nmb is age and organ independent, the histamine release was found to be greater because of increased exposure to things

A

atracurium

54
Q

these two nmb cause no significant difference in duration or sensitivity to the elderly

A

pipecurium and mivacurium

55
Q

no difference in onset time but prolonged recovery with this nmb in the elderly mainly due to decreased liver/kidney function

A

rocuronium

56
Q

with this nmb, recovery times are prolonged in obese pop so dose based on ideal body weight

A

vecuronium

57
Q

there is no significant difference with this nmb in the obese pop

A

atracurium

58
Q

dose this nmb based on ideal body weight in the obese pop

A

roc

59
Q

due to plasma cholinesterase, dose with drug based on total body weight in the obese pop

A

SCh

60
Q

what measurement matters in ideal body weight?

A

height

61
Q

if this is given prior to admin of recuronium, you will see a decreased onset time (works faster)

A

ephedrine because it increases HR and CO so gets to site faster

62
Q

if this is given prior to admin of rocuronium, the onset time was increased by 26%

A

esmolol because of decreased CO, EF so took longer to travel to sites

Pharmacology 680 (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions