Neuromuscular Blocking Agents Flashcards
(121 cards)
1
Q
Succ MOA
A
Mimics the action of Ach.
2 molecules of Ach linked by acetate methyl groups.
Partial agonist at nicotinic Ach receptors and attaches to one or both of the alpha subunits
depolarizing the ion channels at the post junctional membrane.
Sustained opening and depolarization prevents propagations of a new action potential.
2
Q
Succ USE
A
Tracheal intubation
immobility during surgery
3
Q
Succ Dose IV
A
1 mg/kg
range 0.3-1.1 mg/kg
4
Q
Succ Dose IM
A
3-4 mg/kg
5
Q
Succ Onset
A
30-60 seconds
6
Q
Succ Duration
A
4-6 minutes
very short acting
7
Q
Succ Peak
A
30-60 seconds
8
Q
Succ Elimination
A
Excreted in the Urine
9
Q
Succ metabolism
A
Hydolysis
Plasma Pseudocholinesterases
10
Q
Succ Adverse reaction
A
Cardiac Hyperkalemia Myalgia Myoglobinuria IIOP IICP Salivation Histamine Release *rare
11
Q
Succ Contraindications
A
Hypersensitivity/anaphylaxis *peds dt Duchennes Open globe MH Atypical plasma cholinesterase
12
Q
succ classification
A
dicholine ester depolarizing neuromuscular blocker
13
Q
Brand name of Succ
A
Anectine
14
Q
How is Succ supplied?
A
20 mg/mL
10 mL vial
200 mg total
15
Q
Brand name of Vecuronium
A
Norcuron
16
Q
How is vec supplied?
A
1mg/mL
10 mg reconstitute to 1 mg/mL
17
Q
Mechanism of Action of Vec
A
competitive antagonist with ACh at the nicotinic cholinergic receptor post synaptic membrane end plate bind to 1 alpha subunit --> NMB some presynaptic effect
18
Q
what is Vec used for?
A
Tracheal intubation
Immobility during surgery
Facilitate mechanical
Ventilation
19
Q
intubating dose of Vec
A
0.08-0.12 mg/kg
20
Q
maintenance dose of Vec
A
0.01-0.015 mg/kg
21
Q
dose for shivering with Vec
A
8-12 mg
22
Q
onset of vec
A
2.5-3 minutes
23
Q
DOA of vec
A
20-35 minutes
longer with elderly
45-65 minutes
24
Q
peak of vec
A
3-5 minutes
25
half life of vec
65-75 minutes
26
elimination of vec
biliary: excretion/feces (40-75 %)
renal 25-35 %
redistribution and reversal in Cholinesterase I primary way to stop blockade
27
metabolism of vec
minimal hepatic
spontaneous deacetylation
active metabolite
28
Adv reactions with Vec
RARE- CV- bradycardia with opiods
| cv collapse, edema, flushing, hypersensitivity reaction
29
contraindications with vec
Hypersensitivity/anaphylaxis reaction
BURN patients (>30% will be resistant for 5-7 days post insury)
Immobilization
Acute Quadriplegic Myopathy Syndrome in patients taking corticosteriods
30
brand name of Rocuronium
Zemuron
31
How is Rocuronium supplied?
10 mg/mL
32
classification of Rocuronium
intermediate acting
monoquaternary aminosteriod NDMB
derivative of vecuronium
it was designed to speed onset- less potent- more drug given able to occupy more receptors
33
MOA rocuronium
```
competitive antagonist with ACh
at the nicotinic cholinergic receptor
post synaptic membrane end plate
bind to 1 alpha subunit --> NMB
some presynaptic effect
```
34
use of roc
Tracheal intubation
Immobility during surgery
Facilitate mechanical
Ventilation
35
intubating dose of roc
0. 45-9 mg/kg
| 0. 6 mg/kg
36
RSI dose for roc
0.6-1.2 mg/kg
| 1 mg/kg approaches the onset of such 30-60 sec
37
maintenance dose of rocc
0.1-0.2 mg/kg
| 10-20 minutes per dose of maintenance
38
defasciculation dose of roc
0.03-0.06 mg/kg
| give 1.5-3 minutes before succ
39
onset of roc
1-2 minutes for intubating dose
40
peak of roc
4 minutes
41
half-life of roc
60-144 minutes
42
elimination of roc
feces 50%
urine 30%
reversal is primarily from redistribution
gradual metabolism
excrete gradually
Cholinesterase- Inhibitors inhibit acetylcholinesterase enzyme activity, stops Ach-esterase activity, increase Ach, stop block
43
metabolism of roc
Minimal hepatic
5-10% activity of the parents drug
44
Adverse reactions of Roc
Slight vagolytic tendencies- increase HR
HTN/HypoTN
Anaphylactoid rxn
RHF worsensed
Vessel irritant
Rare- ECG changes, anaphylactoid, anaphylaxis, arrhythmis, bronchospasm, edema at lite, hiccupts, pruritis, nausea, PVR increased, rash, rhonchi, shock, tackycardia, vomiting, wheezing
45
contraindications of roc
ypersensitivity
BURN patients
Immobilization- increased resistance
Acute Quadriplegic myopathy syndrome
In pt with corticosteroids
46
brand name of pancuronium
pavulon
47
classification of pancuronium
bisquaternary aminosteriod
| non-depolarizing neuromuscular blocker
48
MOA of pancuronium
Long acting
Competitive antagonist with Ach at the nicotinic cholinergic receptors at the end plate of muscle. Binds to 1 alpha subunit of the post-synaptic receptor in a competitive fashioin.
49
use of pancuronium
Tracheal intubation
Immobility during surgery
Facilitate mechanical
Ventilation
50
intubating dose of pancuronium
0. 1 mg/kg
| 0. 08-0.12 mg/kg
51
surgery dose of pancuronium
0.06-0.1 mg/kg
52
maintenance dose of pancuronium
0.01mg/kg (60-100 minutes after first dose and then 0.01 mg.kg every 25-60 m ins
53
continuous infusion dose of pancuronium
1-2 mcg/kg/min
54
how much to reduce the pancuronium dose with renal failure
50% reduction with renal impairment
55
onset of pancuronium
3-5 minutes
| SLOW
56
duration of pancuronium
60-120 minutes
57
peak of pancuronium
3-5 minutes
58
half life on pancuronium
110 minutes
59
elimination of pancuronium
55-70% excreted in urine as unchanged drug
60
metabolism of pancuronium
Hepatic 30 %-45%
Deacetylation to active metabolite 1/3-1/2 activity of parent drug
61
adverse effects of pancuronium
CV: Vagolytic, increased HR, BP, CO
Derm: rash, itchy, erythema,burning in vein
GI- salivation
Neuro- muscle weakness
Resp- wheezing/bronchospasm
Hypersensitivity
62
contraindications of pancuronium
Hypersensitivity
BURN patients
Immobilization- increased resistance
Acute Quadriplegic myopathy syndrome
In pt with corticosteroids
63
brand name of mivacurium
mivacurium
64
how is mivacurium supplied?
50 mg/ 5mL or 100 mg/10mL
| 10mg/1mL
65
classification of mivacurium
bisquaternary benzylisoquinolinium
| NDNMB
66
MOA of mivacurium
Competitive antagonist
main site of action on nicotinic cholinergic receipts
at the end plate of muscle
binding site of Ach
some presynaptic receptor effect (release of ACh)
80-90% of receptors must be blocked to see reduction in twitch height
67
use of mivacurium
tracheal intubation
immobility during surgery
facilitate mechanical ventilation
68
intubation dose of mivacurium
0.25 mg/kg
69
continuous infusion of mivacurium
3-15 mcg/kg/min
70
onset of mivacurium
2-3 minutes
71
peak of mivacurium
2-3 minutes
72
duration of mivacurium
12-20 minutes
73
half life of mivacurium
1-3 minutes
74
metabolism of mivacurium
Hydolyzed by plasma cholinesterases at 80% the rate of Succs metabolism
Hydrolysis is concentration dependent
More drug = faster hydrolysis
75
Adverse reactions with mivacurium
HISTAMINE → hypotension, tackycardia, bronchospasm
Caution in asthmatics
Hypotension more pronounced with hypertensive ptd
Pts with cholinesterase deficiency or reduced plasma cholinesterases
NO CV affect on cardiac muscarinic receptors (like pancuronium OR block ganglionic nicotinic receptors like d-tubocurine) so less hypotenion or tacky cardia but the histamine offsets these benefits
76
contraindications with mivacurium
Atypical plasma cholinesterase patients → prolonged blockade
asthmatics
77
what is a normal dibucane number?
80%
78
what is a dibucane number of someone who is homozygous for atypical variant form of atypical plasma cholineserases
20%
20% of plasma cholinesterase was inhibited by admin of dibucaine
3 hours of blockade
mivacurium and pancuronium
79
brand name of cisatracurium
nimbex
80
how is cisatracurium supplied
10 mg/5mL
20 mg/10 mL
2mg/1mL
81
classification of cisatracurium
intermediate acting
benzylisoquinolinium
NDNMB
82
how much more potent is cisatracurium than atrracurium?
4x
83
MOA of cisatracurium
Competitive antagonist
main site of action on nicotinic cholinergic receipts
at the end plate of muscle
binding site of Ach
some presynaptic receptor effect (release of ACh)
80-90% of receptors must be blocked to see reduction in twitch height
84
use of cisatracurium
tracheal intubation
immobility during surgery
facilitate mechanical ventilation
85
intubating dose of cisatracurium
0.15- 0.2 mg/kg
86
dose of cisatracurium after succs is used to intubate
0.1 mg/kg
87
maintenance dose of cisatracurium
0.03 mg/kg 40-60 minutes after initial dose
| 20 minute intervales
88
infusion dose of cisatracurium
3mcg/kg/min
1-2mcg/kg/min
consider reduction of infusion by 30-40 % with volitiles
89
onset of cisatracurium
2-3 min
90
peak of cisatracurium
3-5 minutes
91
duration of cisatracurium
20-35 minutes
92
half life of cisatracurium
22-29 minutes
93
metabolism of cisatracurium
NO ester hydrolysis
| compared to atracurium
94
elimination of cisatracurium
77% hoffman elimination
non-enzymatic base catalyzed reaction to spontaneous degradation at normal body temp and pH
16 % renal
95
what accelerated hoffman elimination?
alkalosis
96
what slow hoffman elimination?
acidosis and hypothermia
97
how does the laundosine production compare between cisatracurium and atracurium?
cisatracurium is 5x less than atracuium
98
adverse reaction with cisatracurium
RARE/MILD
histamine- suggestive
bradycardia
99
contraindications with cisatracurium
Hypersensitivity
BURN patients
Immobilization- increased resistance
100
conditions that antagonize NMB
| LESS BLOCK
```
alkalosis
hypercalcemia
demyelinating lesions
peripheral neuropathies
denervation
infection
muscle trauma
DM
acetylcholinesterase inhibitors
burn injury 10 post injury peak 40 days decline 60 day
```
101
conditions that potentiate NMB
| MORE BLOCK
```
electrolyte abnormalities
severe hyponatremia
severe hypocalcemia
severe hypokalemia
hypermagnesemia
hypothemia
neuromuscular disease
acidosis
acute intermittent porphyria
eaton lambert syndrome
myasthenia gravis
calcium channel blockers
aminoglycosides( Gent, tobra)
inhalation anesthetics
lithium
magnesium salts
procainamide
quinidine
loop diuretics
```
102
brand name of atracurium
atracurium
103
how is atracurium supplied
50 mg/5mL
100 mg/10mL
10mg/mL
104
classification of atracurium
intermediate acting
bisquaternary benzylisoquinolinium
NDNMB
10 sterioisomers
105
MOA of atracurium
Competitive antagonist
main site of action on nicotinic cholinergic receipts
at the end plate of muscle
binding site of Ach
some presynaptic receptor effect (release of ACh)
80-90% of receptors must be blocked to see reduction in twitch height
106
use of atracurium
tracheal intubation
immobility during surgery
facilitate mechanical ventilation
107
intubating dose of atracurium
0.4-0.5 mg/kg
108
Maintenance dose of atracurium
0.08-0.1 mg/kg every 20-45 minutes initially then 15-25 minutes
109
Initial dose after succ of atracurium
0.3-0.4 mg/kg
110
Infusion dose of atracurium
9-10 mcg/kg/min (maintained at 5-9 mcg/kg/min
111
ICU paralysis dose for atracurium
IV: bolus 0.4-0.5 mg/kg then 4-20 mcg/kg/min
112
onset of atracurium
2-2.5 minutes
113
duration of atracurium
20-35 min (95% recovery in 60-70 minutes)
114
peak of atracurium
3-5 minutes
115
half time of atracurium
2 minutes distribution to terminal 20 minues
116
elimination of atracurium
Hoffman Elimination 1/3 non-enzymatic base catalyzed reaction leading to spontaneous degradation at normal body temp and pH
LAUNDANOSINE- not active at NMJ causes CNS stimulation
70% laudanosine is excreted in bile- biliary obstruction can lead to accumulation of the metabolite
117
what does laundanosine cause as a metabolite of atracurium
Increased volatile requirement
Vasodilation
118
metabolism of atracurium
Hydrolysis by non-specific plasma esterases 2/3
Laundosin is the metabolite for both ester hydrolysis and Hoffman
Non-renal/hepatic
119
adverse reactions of atracurium
Mild/RARE
Flushing
Increase HR decrease MAP 5 min recovery
Facial and truncal flushing
Bradycardia
0.5 mg/kg
120
contraindications with atracurium
AVOID WITH ASTHMATICS
Burns
Immobilization
Hypersensitivity/ anaphylactic
121
typical dose with atracurium
```
50 mg for intubation
may need more if big male
need to re-dose after 30 minutes
usually about 10-20 mg
lasts 30 minutes
takes 2 minutes to get on board
```
