Paralytics/Locals Flashcards
(170 cards)
1
Q
myalgias and fasciculations from succs are more common when
A
young adults, women, people who rarely participate in muscular activity
2
Q
Chloroprocaine max dose, max total dose, and pKa
A
Max dose: 11mg/kg
Max total dose: 800mg
pKa: 8.7
3
Q
Potency of locals is related to what
A
lipid solubility
4
Q
what increases conduction velocity of axons
A
myelination and larger fiber diameter
5
Q
Lidocaine max dose, max total dose, and pKa
A
Max dose: 4.5mg/kg
Total max dose: 300mg
pKa: 7.9
6
Q
Technique for a Bier block
A
two tourniquets for comfort, inflate distal first, inject lido, inflate proximal then deflate distal, minimum tourniquet time is 20 minutes
7
Q
Duration of succinylcholine
A
5-10 minutes
8
Q
what is tetanus
A
continuous stimulation for 5 seconds as 50 or 100hz
9
Q
Masseter spasm can be an early sign of what
A
MH
10
Q
why does bupivacaine have greater risk of cardiac toxicity
A
greater affinity for voltage gated sodium channel
11
Q
cisatracurium duration
A
55-75 minutes after intubation dose
12
Q
in a nicotinic receptor what ions pass through
A
Sodium, calcium, and potassium. Chloride does not
13
Q
if given sugammadex how long should people on birth control use a different form of contraceptives
A
1 week
14
Q
elimination for atracurium
A
hoffman elimination and nonspecific plasma esterase, temp and pH dependent
15
Q
what metabolizes esters
A
hydrolysis by pseudocholinesterase
rapid rate of clearance reduces risk of toxicity
16
Q
cisatracurium elimination
A
hoffman elimination (faster with alkalosis and hyperthemia)
17
Q
definition of clinical duration
A
time from drug administration to 25% recovery of the twitch response
18
Q
does atracurium have histamine release?
A
yes
19
Q
succs in not recommended in kids why
A
risk of massive rhabdo, hyperkalemia, and death in undiagnosed muscle disease
20
Q
Roc dose
A
.6-1.2mg/kg
21
Q
Vec elimination
A
renal and hepatic, has metabolite
22
Q
relationship between pKa and pH for locals
A
the closer the pKa is to the pH, the faster the onset
23
Q
neostigmine duration
A
45-90 min
24
Q
muscles list of onset from NMBD
A
- eye muscles
- extremities
- trunk of body
- abdominal muscles
- diaphragm
25
what is a Bier block
iv injection of local anesthetic into an extremity isolated from the rest of the systemic circulation
26
succinylcholine dose
1-1.5mg/kg
27
what percentage of injected succinylcholine reaches NMJ
10%
28
pregnancy relation to locals
increased sensitivity, reduce dose
29
Succinylcholine has what effect on potassium in surrounding membrane
increases potassium permeability
30
what is the primary determinant of duration of action for locals
protein binding
31
neostigmine metabolism and elimination
renal 50%, elimination 50%
32
what is the preferred ToF location
adductor pollicis via stimulation of ulnar nerve
33
why does vascularity impact risk of toxicity
more vascular a site is the more drug will be absorbed
34
Roc is a derivative of what
Vec
35
Roc duration
30-60 minutes
36
Order of fibers becoming blocked
Type B and C first (smaller)
A beta, gamma, delta second
A alpha last
37
What is the first muscles to be affected by NMBD
eye muscles
38
in elderly patients, what drug types should you look out for before giving succs
Alzheimer's drugs, many are acetylcholinesterase inhibitors so they may prolong action of succs
39
mivacurium drawbacks
histamine release, especially if given rapidly
40
amount of blockade when 3 twitches present
75-80%
41
which NDMR are benzylisoquinolium compounds
atracurium, cisatracurium, mivacurium
42
Bupivacaine max dose, max total dose, and pKa
Max dose: 2mg/kg
Max total dose: 175mg
pKa: 8.1
43
Define depolarizing muscle relaxants
agonists at postsynaptic nicotinic acetylcholine receptors, mimic acetylcholine and cause sustained muscle contraction
44
definition of total duration of action
time from drug administration to 90% recovery of twitch response
45
what are risk factors for prolonged duration of succinylcholine
physical status, age, sex, hepatic disease, pregnancy, hx of cancer, use of metoclopramide
46
interrupting PTC
the higher the count the less intense block
47
do locals bind to alpha subunit on the inside or outside of sodium channel
inside
48
how many molecules of nondepolarizing muscle relaxants are needed to produce a block
one molecule of drug binding to one alpha subunit
49
factors that increase potency of NDMR
inhalation agents (des>sevo>iso), Abx, hypothermia, electrolytes, high doses of local
50
are allergies more common with esters or amides
esters
51
what influences toxicity of local anesthetics
absorption
52
how to reduce post op muscle pain from succs
small doses of NDMR
53
Lipid dose for LAST
initial bolus: 1.5mL/kg of 20% lipid emulsion
Infusion: .25mL/kg/min
54
mivacurium elimination
pseudocholinesterase
55
Na+ enters the cell causing what?
depolarization
56
cisatracurium onset
intermediate, much slower than roc
57
what is the most widely used NDMR in US
Roc
58
how is sugammadex eliminated
excreted in urine
59
what is the composition of succinylcholine
2 molecules of acetylcholine
60
Liposomal bupivacaine dose
266mg
61
what are factors for magnitude of LAST
dose, vascularity of injection site, presence of epi, physiochemical properties
62
why are neuromuscular agents #1 cause of anaphylaxis in OR
their structure interacts with IgE, more frequent with amniosteroids
63
why is succs not recommended in burns
extreme hyperkalemia
64
what are the cardiac effects of NDMR
no direct effects
some indirect effects from histamine release in atrac and mivac
65
Ropivacaine max dose, max total dose, and pKA
Max dose: 3mg/kg
Total max dose: 200mg
pKa: 8.1
66
succs increases K+ by how much
.5-1 in heathy adults
67
Drugs that can cause methemoglobinemia
Benzocaine, cetacaine, prilocaine, EMLA, nipride, nitro, slufonamides, phenytoin
68
factors that decrease potency of NDMR
chronic anticonvulsant therapy
69
what do local anesthetics do
reversibly block conduction of electrical impulses along nerve fibers
70
side effects of acetylcholinesterase inhibitors
bradycardia, brochoconstriction, increased GI motility, N/V, urinary urgency, miosis
71
dantrolene mechanism of action
binds to ryanodine calcium channel leading to reduced calcium efflux from sarcoplasmic reticulum
72
onset for edrophonium
5-10 min
73
larynx and diaphragm reaction to NMBD in comparison to peripheral muscles
more resistant, blockade develops faster (more blood delivered), lasts shorter, and recovers faster
74
what is neostigmine paired with
glycopyrrolate
75
Roc elimination
hepatic and renal, primary is biliary, no metabolite
76
define nondepolarizing muscle relaxants
competitive antagonist at nicotinic acetylcholine receptors, prevent ACh from binding
77
what are factors that influence vascular uptake and plasma concentration of locals
site of injection, tissue blood flow, physiochemical properties of the local anesthetic, metabolism, and addition of a vasoconstrictor
78
Meds not recommended in LAST treatment
Lido, procainamide
Calcium channel blockers and beta blockers
Vaso
79
Prilocaine max dose, max total dose, and pKa
Max dose: 8mg/kg
Total max dose: <70kg 500mg, >70kg 600mg
pKa: 7.9
80
Vec onset
dose dependent, intuabation dose is 3.1 minutes
81
drugs that reduce pseudocholinesterase activity
metoclopramide, esmolol, neostigmine, echothiopate, oral contraceptives, cyclophosphamide, MAOI, nitrogen mustard
82
Vec dose
.1mg/kg
83
what metabolizes amides
P450 enzymes
impacted hepatic function prolongs elimination half life
slower than ester metabolism
84
what is liposomal bupivacaine
sustained release of local over days, works up to 96 hours
85
how to interrupt tetanus
muscle contraction sustained for entire 5 seconds without fade, significant paralysis is unlikely
86
what do locals bind to
locals reversibly bind to alpha subunit of the voltage gated sodium channel
87
which anticholinergics cross BBB
atropine and scopolamine
88
neostigmine dose
.02-.07mg/kg
89
90
Levobupivacaine max dose, max total dose, and pKa
Max dose: 2mg/kg
Max total dose: 150mg
pKa: 8.1
91
What number on ToF are we looking for to determine recovery
ToF > .9
92
what is dantrolene's effect when given with calcium channel blockers
cardiac depression
93
numbers of dibucaine test
70-80: normal
50-60: heterozygous
20-30: atypical
94
how long before larynx effects of succinylcholine
34 seconds when given 1mg/kg
95
when is post-tetanic count (PTC) used
when there is no response to any commonly used tests due to 100% paralysis
96
elderly response to NDMR
delayed onset time due to slow circulation
97
steroidal NDMR
Roc, Vec, Panc
98
definition of recovery index
time from 25% to 75% recovery of twitch response
99
pancuronium aspects
potent and long acting
direct sympathomimetic stimulation
renal elimination
metabolite half as potent as parent
100
what subunits are around a central ion channel
alpha, beta, delta, and epsilon
101
what does magnesium do to locals
increases duration
102
what is the definition of fade
inability to sustain a response to repetitive nerve stimulation
103
what causes the highest incidence of transient neurological symptoms
intrathecal injection of lidocaine
104
Roc is stable at room temp for how long
30 days
105
dantrolene dose
2.5mg/kg, dissolve with 60cc sterile water
106
amount of blockade when 1 twitch present
90-95%
107
Roc onset
45-90 seconds
108
cisatracurium advantages
maintenance of CV stability, non organ dependent elimination, lack of histamine release
109
binding of __ acetylcholine molecules to ____ subunits leads to conformation change and opening of the channel
2, alpha
110
Diseases that reduce pseudocholinesterase activity
atypical pseudocholinesterase, severe liver disease, chronic renal, burns, neoplasm, advanced age, malnutrition, pregnancy
111
Lidocaine w/ epi max dose, max total dose, and pKa
Max dose: 7mg/kg
Total max dose: 500mg
pKa: 7.9
112
duration of atracurium
30-60 minutes
113
why does roc have a more rapid onset
less protein bound (46%)
114
which block type exhibits fade
Phase II
115
mivacurium duration
15-20 minutes
116
neostigmine onset
5-15 min
117
how is it recommended to given edrophonium
incremental injection due to rapid onset and short duration
118
Chloroprocaine w/ epi max dose, max total dose, and pKa
max dose: 14mg/kg
Max total dose: 1000mg
pKa: 8.7
119
what is cauda equina syndrome
diffuse injury across lumbosacral plexus that produces varying degree of sensory anesthesia, bowel and bladder dysfunction, and paraplegia
120
autonomic fibers are what letter classification of fibers
B fibers
small, lightly myelinated, blocked first
121
MOA of sugammadex
encapsulates and forms water-soluble complex at 1:1 ratio with steroidal NMBD
122
atypical pseudocholinesterase lengthens effect of succinylcholine by how much
4-8 hours
123
acetylcholinesterase is synthesized where
in liver but found in plasma
124
what does single twitch measure
indicates whether 100% paralysis is present
125
what is being measured when using ToF
depolarization and contraction of a muscle
126
can locals bind when receptors are in resting state
NO, the more frequently the channels are open the more time available for local anesthetic to bind
127
what are the contents of EMLA
2.5% lido and 2.5% prilocaine
128
what is laudanosine
metabolite of atrac and cisatrac, CNS stimulant that can produced seizures
129
when would succinylcholine exhibit as phase 2 blcok
with excessive doses or infusion
130
mivacurium onset
dose dependent, 1.5-4 minutes
131
resting membrane potential in peripheral nerve
-70mV, threshold potential is -55mV
132
relation of potency and onset with NDMR
inversely proportional
low potency = rapid onset
high potency = slow onset
133
how does raising pH effect locals
brings pH closer to pKa increasing lipid solubility which speeds onset
134
Bupivacaine w/ epi max dose, max total dose, and pKa
max dose: 3mg/kg
Max total dose: 225mg
pKa: 8.1
135
in LAST, are excitatory or inhibitory pathways blocked first
inhibitory blocked first, leads to seizures
136
what dose of succs is given if you also give NDMR for fasciculations
1.5-2mg/kg
137
why do we add vasoconstrictors to locals
they reduced the rate of vascular absorption
138
dose for edrophonium
500-1000mcg/kg
139
what are the benefits of alkalization of locasl
results in less pain on injection
140
Treatment for methemoglobinemia
methylene blue 1-2mg/kg IV
141
Procaine max dose, max total dose, and pKa
Max dose: 7mg/kg
Max total dose: 350-600mg
pKa: 8.9
142
in ToF monitoring, is the facial nerve better for monitoring onset or recovery?
onset
143
succs increases IOP by how much
5-15 for as much as 10 minutes
144
what is the risk of using benzocaine
methemoglobinemia
145
amount of blockade when 2 twitches present
80-85% blockade
146
dantrolene side effects
phlebitis or tissue necrosis, diuresis, skeletal muscle relaxation, nausea, diarrhea, blurry vision, uterine atony
147
what is the most important factor for onset of action in locals
ionization
more ionized = slower penetration
148
motor fibers are what letter classification of fibers
A-alpha
blocked last, loss of motor function
149
what is Train of four ratio
compares 4th twitch to the 1st twitch, when the 4th twitch is 90% of the 1st twitch recovery is indicated
150
in ToF monitoring, is the ulnar nerve better for monitoring onset or recovery?
best for recovery, one of the last muscles to recover from NMBD
151
what is the most common cause of LAST
accidental intravascular injection
152
what does progressive increases in concentrations of locals do
interrupts transmission of autonomic, somatic sensory, and somatic motor impulses
153
what does it mean when fade is present
partial blockade with NDMR
154
what are the CNS effects of NDMR
none
155
onset for atracurium
1.2-2.8 minutes, larger doses reduces onset time
156
Sensory fibers are what letter classification of fibers
C and A-delta
blockage leads to loss of touch and pressure sensation
157
Mepivacaine max dose, max total dose, and pKa
Max dose: 7mg/kg
Max total dose: 400mg
pKa: 7.6
158
amount of blockade when 0 twitches present
100%
159
LAST treatment
airway management w/ 100% FiO2, circulatory support, prevent hypoxia and acidosis (enhances ion trapping in brain), lipids
160
Vec duration
30-60 minutes
161
dysrhythmias from succs usually occur when
5 minutes after a second dose is given
162
what does dexmedetomidine do to locals
prolongs effects
163
duration of edrophonium
30-60 min
164
what is the drawback of measuring the facial nerve
hard to be conclusive what is being measured due to multiple small nerves and muscles in the area
165
Side effects of succinylcholine
bradycardia/tachycardia, increase K, increased IOP, increased ICP, increased intragastric pressure, MH
166
what is the hydrolysis products of acetylcholine after acted on by acetylcholinesterase
acetic acid and choline
167
what enzyme is responsible for stopping the process of muscle contraction by removing acetylcholine
acetylcholinesterase
168
describe structure of local anesthetics
lipophilic (benzene ring) head, a quaternary amine (hydrophilic) tail, and either an ester or an amide middle chain
169
Depolarizing block of succinylcholine is usually preceded by what?
fasciculation due to retrograde conduction of action potentials
170
definition of onset time
time from drug administration to maximum effect
