Overview of Anesthesia Lecture 3 Flashcards
1
Q
What should be obtained before administering IV agents?
A
Consent
2
Q
Thiopental (Pentathol) dose
A
3-5 mg/kg/IV
3
Q
What is the onset time for Thiopental (Pentathol)?
how about duration
A
15-30 seconds
5-10 minutes
4
Q
What is the typical dose of Methohexital (Brevital) for IV administration?
what about for kids
A
1-1.5 mg/kg/IV
25 mg/kg RECTAL
5
Q
onset and duration of methohexital (Brevital)
A
onset- 15-30 sec
duration- 5-10 min
6
Q
What is the mechanism of action (MOA) of Dexmedetomidine (Precedex)?
A
Selective alpha-2 agonist
decreases need for narcotics
7
Q
What are the side effects of Dexmedetomidine?
A
*Bradycardia
*Hypotension
8
Q
What is a common use for Benzodiazepines in anesthesia?
A
Anxiolysis
9
Q
What is the onset time for Midazolam (Versed)?
A
30-60 seconds
10
Q
midaz dosing for induction
A
1-3 mg IVP
11
Q
MOA midazolam and how is it metabolized
duration
A
(MOA)- attaches to the alpha subunit on the GABA(A) receptor to produce anesthesia-
Metabolism- CYP3A4 & CYP3A5
20-60 minutes
caution ages >65
12
Q
What is the duration of action for Remimazolam (Byfavo)?
A
Ultrashort acting
good for procedures <30min
13
Q
Remimazolam (Byfavo) dose for induction
A
2.5-5 mg IVP over 1 min
14
Q
MOA for flumazenil (Romazicon)
how’s it metabolized
A
Mechanism of action (MOA)- competitive antagonist at the GABA-A receptor
metabolism- Liver
15
Q
who should not receive Flumazenil (Romazicon)
A
chronic benzo users- can cause sz activity d/t it’s pure benzo antagonism
16
Q
What is the dose and maximum dose for Flumazenil (RoMazicon)?
A
Dose: .2mg q1Min
MAX- 0.6-1.0 mg
17
Q
Etomidate (Amidate) for IV induction?
onset/duration/MOA/metabolism
A
Induction: 0.2-0.3 mg/kg/IV
ONset- 15-45 sec
duration- 3-10 min
MOA- Works on GABAA receptor to produce unconsciousness, and reticular activating system
metabolism- liver
18
Q
T/F- etomidate has analgesic properties
A
false- need to give separate analgesia
19
Q
What is the mechanism of action for Ketamine (Ketalar)?
onset/duration
A
N-methyl-D-aspartate (NMDA) receptor antagonist
NMDA) receptor antagonist
-interferes w/ communication b/t limbic and thalamus systems
onset- 30-60 seconds
duration-5-10 minutes
Good analgesic- (somatic > visceral pain)
Increases CMRO2
20
Q
indications/dosing/concentration for ketamine
and metabolism so we don’t have 10000 cards
A
Dose- 1-2 mg/kg/IV-
* (3-5 mg/kg IM KIDS)
Indications- induction or adjunct to MAC (usually adjunct)
* Concentration- usually 50 mg/ml
metabolism- hepatic microsomal enzymes
21
Q
T/F- ketamine causes respiratory depression and is bad for asthmatics
A
F
no respiratory depression- can offset propofol depression
good bronchodilatior for pt’s with reactive air-ways
22
Q
other uses for ketamine besides sedation (4)
A
treats depression
SI
chronic pain
decreases opioid requirement
23
Q
Fill in the blank: Propofol promotes _______ mediated inhibitory neurotransmission.
to produce sedation or LOC
A
GABAA
24
Q
What is a significant concern when using Propofol?
A
Propofol Infusion Syndrome (PIS)
caution w/ egg allergies/ lecithin/ peanut/soy- avoiid in peds
25
induction dose of prop
onset
duration
2-2.5 mg/kg/IV for induction**-
__- 2.5-3.5 mg/kg/IV for PEDS
20-200 mcq/kg/min infusion
* Onset- 15-45 seconds
* Duration- 5-10 minutes
26
# whats this
2,6 diisopropylphenol
Propofol!
26
what do you give prior to prop during induction and WHYYY
can administer lidocaine prior to injection at 0.5 mg/kg/IV** like a minute before
Binds to voltage-gated Na channels & prevents Na flow through the channel
If using lidocaine as part of induction to blunt sympathetic response: the dose is 1-1.5/mg/kg/IV
27
MOA for opioids
A. Binding in specific areas in CNS- medulla, grey matter, locus serulious
B. Binding in peripheral tissues and spinal cord-
C. Receptors which mediate the action of opioid drug
Mu (Mu1= bradycardia)
Kappa
Delta
G-coupled proteins
28
What is a potential risk associated with opioid use in cancer patients?
Cancer recurrence
controversial
29
What does MAC stand for in anesthesia?
Minimum Alveolar Concentration
Or Monitored Anesthesia care
For 2 things we need to know you'd think they could come up with another name
30
goal of inhalational anesthesia
how do you know if you have MAC
o Induction
Occurs when anesthetizing partial pressure achieved in brain is = to PP of the gas
brain is final site- for impact of selected agent
look at inspired and expired concentration
o Goal of Inhalational Anesthesia - Maintain brain concentration
monitor with agent monitor
31
what are the 3 characteristics of anesthesia
Amnesia- don’t remember
Never say an absolute- there is a 0.1 percent chance that they could have recall during MAC
Analgesia- pain free
Akinesia- not moving
32
What is the weakness of Sevoflurane (Ultane)?
*Unstable in CO2 absorbers
*Can cause fires
33
What is the typical induction dose for Propofol?
2-2.5 mg/kg/IV
34
True or False: Isoflurane has a pungent odor.
True
35
What is the effect of adding N2O on MAC?
Reduces MAC by 2/3
36
______ MAC decreases risk of recall
.4-.5 MAC
37
What should be monitored to maintain brain concentration during anesthesia?
Inspired and expired concentration
38
What is the MOA of opioids?
Binding to morphine receptors
39
Fill in the blank: Ketamine is an excellent _______ for patients with asthma.
Bronchodilator
40
What is the concentration of Midazolam (Versed) for IV sedation?
1 mg/ml or 5 mg/ml
41
What is the primary action of Dexmedetomidine?
Decreases the need for narcotics
42
What is the duration of action for Remifentanil?
3-5 minutes
43
What is the typical dose for Sufentanil compared to Fentanyl?
0.25 mcg/kg/IV (ten times more potent than Fentanyl)
44
What is a side effect of Flumazenil in chronic Benzodiazepine patients?
Seizure activity
45
What is the ideal characteristic of an anesthetic agent regarding solubility?
Poorly soluble in blood
46
What is the relationship between MAC and potency?
MAC relates the agent to potency
47
What is the strength of Isoflurane?
Good muscle relaxation
48
What is the mechanism of action for Etomidate?
Works on GABAA receptor
49
What is one of the weaknesses of Desflurane?
Boils at room temperature
50
What are the three characteristics of anesthesia?
*Amnesia
*Analgesia
*Akinesia
51
What does the term 'emergence' refer to in anesthesia?
Stage 3 -> Stage 2 -> Stage 1
52
Fill in the blank: The ideal anesthetic agent should be _______ and non-toxic.
Poorly soluble in the blood
53
What is the effect of Nitrous Oxide on B12 metabolism?
Limits B12 metabolism
54
What is a contraindication for using Nitrous Oxide?
Middle ear surgery- b/c expansion of gas
Laser surgery- b/c laser is an oxidizer = risk of fire
Pulmonary hypertension= Increases PVR
History of n/v
Laparoscopic abdominal procedures- distention of bowel then surgeon can’t see anything.
* Takes about 2 hours for it to occur
Greenhouse effect- trivial <0.05%
55
T/F - all inhaled anesthetics carry the risk of MH
true
except for N20 but that barely counts
56
What is the typical concentration of Ketamine for IV induction?
50 mg/ml
57
What is the effect of opioids on cancer cell activity?
May stimulate cancer cell activity
58
What is the primary role of anesthetic agents in surgery?
Induction and maintenance of anesthesia
59
What are the strengths of Sevoflurane?
Similar to isoflurane, can be used for mask induction in pediatric or adult patients
60
What are the weaknesses of Sevoflurane?
Unstable in CO2 absorbers, can cause fires, metabolized to fluoride, costly, trigger for MH
Compound a for extended low flow
61
What evidence exists regarding inhalational agents and cancer?
Some evidence suggests inhalational agents may stimulate cancer cell activity
62
How is Xenon manufactured?
By fractional distillation of liquefied air
63
What is the MAC of Xenon?
71%- not potent, can only give 29% O2
64
What is the blood/gas solubility coefficient of Xenon?
0.115
65
What is the cost of Xenon?
$10 per liter
66
What is a notable side effect of Xenon?
High incidence of nausea/vomiting, diffuses into closed gas space
67
What do muscle relaxants do?
Interfere with physiological sequence of neuromuscular transmission, optimize surgical conditions
68
Physiology of neuromuscular transmission at the NMJ
godspeed
o Physiology of Neuromuscular Transmission at Neuromuscular Junction (NMJ)
1. Presynaptic nerve terminal: contains vesicles with 100 K molecules of acetylcholine (Ach)
2. Influx of Ca: Release of Ach (5,000-10,000 molecules) into NMJ
3. Ach diffuses across cleft: binds to postsynaptic nicotinic receptor-
4. Nicotinic receptor composed of large protein with 5 subunits in a ring
5. At rest - Na/K pump maintains Na outside: K inside producing transmembrane potential of -90 mv
6. Both alpha subunits occupied- Na channel opens**
7. Na/Ca in, K out- T.M.P -45 mv (threshold potential)
8. Action potential= muscle contraction
69
Are muscle relaxants anesthetics?
No
70
What is the first step in the physiology of neuromuscular transmission?
Presynaptic nerve terminal contains vesicles with 100 K molecules of acetylcholine (Ach)
71
What triggers the release of acetylcholine at the NMJ?
Influx of Ca
72
What happens when Ach binds to the postsynaptic nicotinic receptor?
Na channel opens
73
What is the transmembrane potential at rest?
-90 mv
74
What occurs when both alpha subunits of the nicotinic receptor are occupied?
Na channel opens
75
What is the threshold potential for action potential?
-45 mv
76
What metabolizes acetylcholine?
Acetylcholinesterase/true cholinesterase or specific cholinesterase
77
How is succinylcholine metabolized?
Succinylcholine- metabolized by butyrylcholinesterase, also known as plasma cholinesterase or pseudocholinesteras
metabolism restores membrane permeability (repolarization)
78
What is the typical concentration of succinylcholine?
20 mg/ml
79
What is the typical dose of succinylcholine for adults/kids?
1-1.5 mg/Kg/IV (70-100 mg) adult
Kids- 2-3 mg/Kg/IV
4-6 mg/Kg/IM
| everyone usually gets 100 mg unless they are hefty
80
What is the onset time for succinylcholine?
30-60 seconds
81
What is the typical duration of succinylcholine?
5-10 minutes
82
What can prolong succinylcholine's effects?
High doses or abnormal metabolism
decreased enzyme levels
late stage preggo
liver/renal failure, dialysis, MI, CHF
Burns, oral contraceptives, malnutrition, steriods
83
What is a common side effect of succinylcholine?
Fasciculations
84
What can succinylcholine cause in patients with burns or neurological injuries?
Hyperkalemia
85
What is a treatment for hyperkalemia caused by succinylcholine?
10% Calcium Chloride IV, hyperventilation, insulin, D50 Glucose, albuterol, dialysis
86
what is the dibucaine number for
tests for abnormal genes that prolong the effects of succ
1 in 500 patients- one normal and one abnormal gene (heterozygous)
1 in 2,000-5,000 patients- two abnormal genes (homozygous)-
| usually not done unless fam hx
87
dibucaine of 70-80 is......
normal
typical homozygous
duration of succ - 5- 10 min
88
heterozygous enzyme for succ means
dibucain is. 50-69
succ lasts longer 20-30 min
89
atypical homozygous enzyme for succ
16-30
succ will be in there for 4-8 hrs
sorry pacu- must wait it out
90
what is another use for succ other than induction
laryngospasm
0.2-0.5 mg/Kg/IV
If positive pressure doesn’t break the spasm or the jaw lift doesn’t work
91
What is malignant hyperthermia?
A condition triggered by succinylcholine, leading to severe muscle contractions
92
What is the incidence of anaphylaxis related to neuromuscular blockers in the USA?
15.3 per 100k procedures
93
What is the primary risk associated with succinylcholine in children?
Hyperkalemic rhabdomyolysis
mortality is 40-50%
treat as same as hyperkalemia
94
What is the dose of succinylcholine for laryngospasm?
0.2-0.5 mg/Kg/IV
95
What can occur during succinylcholine overdose?
Phase II block
Cholinesterase inhibitor will prolong Phase I block
Inhibiting Achase- leads to an increase at NMJ which intensifies depolarization
Decreases hydrolysis of Succinylcholine by inhibiting pseudocholinesterase from breaking it down.
96
What are nondepolarizing muscle relaxants?
Competitive Ach receptor antagonists
97
how much can succ increase serum potassium
who's that bad for apart from everyone
.05-1 meq/l
* can be dangerous in burn patients, neurological patients (spinal cord injury, Guillain-Barre, CVA, muscular dystrophy, MS), massive trauma, prolonged immobility & severe sepsis- WHY?
Can increase more than .5-1 in these peeps
d/t upregulation of ach receptors- they have more receptors can release more potassium
stay open 10x longer than normal cells
risk can last up to 1 year- DO NOT GIVE THEM SUCC
97
Succ CV S/E
* Succinylcholine stimulates all Ach receptors in SNS/PSNS
* Initially hypertensive and tachycardic
* Bradycardia in kids (higher vagal tone) & with second dose in adults- impact on SA node
Kids will need atropine/glyco pre-op to offset risk
Transient but significant enough you’ll need to treat
98
What is the duration of action for intermediate-acting nondepolarizers?
35-45 minutes
99
What is the metabolism of atracurium?
Ester hydrolysis (66%) and Hoffman elimination (33%)
100
atracurium
dose for induction
.4-.5 mg/kg/IL over 30-60 sec
101
what is the only long acting NDMR
pancuronium- 85 min
102
vecuronium
tubing dose
metabolism
onset
Dose: intubation- 0.08-0.1 mg/Kg/IV-
Maintenance- 0.01 mg/Kg/IV
Infusion- 1.0-2.0 mcq/Kg/min** (M & M pg. 212)
Metabolized- 40-50% hepatic & 50-60% renal
onset- 2.5 minutes
103
Tell me the things about cisatracurium (Nimbex)
Dose- 0.1 mg/Kg/IV-
Maintenance- 0.03 mg/Kg/IV
Infusion- 1.0-2.0 mcq/Kg/min** (M & M pg. 212)\
Metabolized- Hoffman elimination (77%) & renal- 16%-
Hoffman – temperature and pH dependent
* **Good for renal / liver failure pts **
No Histamine release
Onset 3 minutes
104
What is the dose of rocuronium for intubation?
onset
metabolism
duration
0.45-0.6 mg/Kg/IV
good for RSI- onset is 60-90 sec
Metabolism- >70% eliminated by biliary excretion & 10-25% by kidney
duration 50 min
| good for RSI
105
What is the primary side effect of rocuronium?
Possible anaphylactic reaction
banned in many countries in Europe
106
What is the duration of action for pancuronium?
85 minutes
107
Pancuronium intubation dose
.08-.1 mg/kg/ IV
108
What is the main side effect of pancuronium?
Hypertension and tachycardia
(inhibits M2 receptor at SA node & stimulates catecholamine release)-
109
What is the order of potency among volatile agents?
Des>Sevo>Iso>N2O
110
What are some antibiotics that interact with muscle relaxants?
*Aminoglycosides
*Tetracycline
*Polymixins
111
What are common anticholinesterase drugs?
*Neostigmine
*Physostigmine
*Edrophonium
112
What is the mechanism of action of anticholinesterase drugs?
Inhibit acetylcholinesterase, allowing accumulation of Ach at NMJ
113
What are the muscarinic side effects of cholinesterase inhibitors?
*Bradycardia
*Increased secretions
*Pupil constriction
*Bronchoconstriction
114
What is the dose of Narcan (Naloxone) for opioid reversal?
0.5-1 mcg/kg/IV
115
What is the mechanism of action of Sugammadex?
Encapsulates rocuronium & vecuronium, forming a rigid complex
116
What is the dose of Sugammadex for reversal of rocuronium?
TOF 2/4- 2 mg/kg/IV
TOF 0/4: PTC > 1- dose is 4 mg/kg/IV
RSI dose with rocuronium at 1.2 mg/kg–
Sugammadex dose-16 mg/kg/IV given 3 mins after roc dose
117
What is the renal and liver elimination percentage for the discussed medications?
75% Renal, 25% Liver
118
What is the recommended IV dose of Atropine per 1 mg of Pyridostigmine?
0.1 mg/IV
119
What is the preferred IV dose of Glycopyrrolate per 1 mg of Pyridostigmine?
0.05 mg/IV
120
What is the primary use of Sugammadex?
For reversal of rocuronium & vecuronium
121
What is the mechanism of action (MOA) of Sugammadex?
Encapsulates rocuronium & vecuronium & forms a very rigid complex
122
What is the IV dose of Sugammadex for TOF 2/4?
2 mg/kg/IV
123
What is the IV dose of Sugammadex for TOF 0/4 with PTC > 1?
4 mg/kg/IV
124
What is the RSI dose with rocuronium?
1.2 mg/kg
125
What is the Sugammadex dose when given 3 minutes after rocuronium?
16 mg/kg/IV
126
What is the onset time for Sugammadex?
2-3 mins
127
What is the MOA of Metoclopramide?
Dopamine antagonist
128
What is the recommended IV dose of Metoclopramide?
10 mg/IV
129
What is the MOA of Droperidol?
dose
Dopamine antagonist
.625-1.25 mg IV
130
What is the FDA black box warning associated with Droperidol?
Prolonged QT; need pre-op EKG
131
What is the IV dose of Ondansetron?
4 mg/IV
132
What is the MOA of Ondansetron?
Serotonin antagonist (5-HT3 receptor antagonist)
133
What is the recommended dose of Decadron for PONV?
4-8 mg/IV
134
What is the MOA of Barhemsys?
Dopamine D2 & D3 receptor antagonist
135
What is the prevention dose of Barhemsys?
5 mg/IV
136
What is the treatment dose of Barhemsys?
10 mg/IV
137
What is the MOA of Toradol?
Non-selective competitive inhibition of cyclo-oxygenase (COX-1 and COX-2)
138
What is the IV dose of Toradol?
30 mg/IV Q 6 hrs.
139
What is the maximum 24 hr. dose of OFIRMEV?
4000 mg
140
What is the IV dose of Caldolor?
400-800 mg/IV over 30 minutes, Q 4-6 hrs.
141
What is the MOA of Ephedrine?
Noncatecholamine sympathomimetic agent
142
What is the typical IV dose range for Ephedrine?
2.5-10 mg/IV
143
What is the MOA of Neosynephrine?
Direct acting alpha-1 adrenergic agonist
144
What is the IV bolus dose of Neosynephrine?
50-100 mcg/IV
145
What is the IV dose of Epinephrine for hypotension?
5-20 mcg/IV bolus
146
What is the IV dose of Labetolol?
2.5-10 mg/IV over 2 minutes
147
What is the MOA of Esmolol?
Short-acting selective Beta-1 antagonist
148
What is the IV dose of Esmolol?
0.2-0.5 mg/kg/IV
149
What is the MOA of Hydralazine?
Smooth muscle vasodilator
150
What is the typical IV bolus dose of Hydralazine?
5 to 20 mg IV every 15 to 20 minutes
151
What is the MOA of Nitroprusside?
Arteriolar & venous smooth muscle relaxant
152
What is the onset time for Nitroprusside?
60-120 seconds
153
What is the first step in the induction sequence for general anesthesia?
Apply monitors, then Pre-oxygenate
154
What is given after pre-oxygenation in the induction sequence?
Fentanyl/midazolam
155
What should be done before administering Propofol in the induction sequence?
Lidocaine prior to Propofol
156
What is checked after administering Rocuronium?
Check TOF in 2-3 mins
157
What is turned on after Rocuronium administration?
Turn on inhalational agent
158
classifications of opioid receptors
159
fentanyl- indication
MOA
dosage dependent upon procedures (low, med, high)
Intraoperative anesthetic dose: 2-50 mcg/kg/IV
Indication- analgesia
Concentration- 50 mcq/ml
Low- 1-3 mcq/kg/IV
Moderate- 5-10 mcq/kg/IV
High- 20-50 mcq/kg/IV up to 75 for CABG
MOA- agonizes Mu receptors to produce analgesia
160
sufentanil is _______ stronger than fentanyl
10x
Intraoperative Anesthetic Dose: 0.25 mcg/kg/IV
161
T/F- fentanyl, sufentanil, morphine, and dilaudid antagonize delta receptors
F- its Mu
162
Remifentanil
metabolism
concern
Unique in its metabolism- plasma erythrocyte and tissue esterase's
Concern-
opioid induced hyperalgesia (OIH)- high postop opioid requirements
* Wears off Very quickly (3-5 min)
* Treat- ketamine or magnesium sulfate
163
IV tylenol
MOA
dose
advantages
MOA- unclear- inhibition of cyclooxygenase (COX), with a predominant effect on COX-2
Advantages-postoperative pain relief, decreased use of opioids & reduced incidence of PONV
Dose- 1000 mg/IV Q 6hrs.
Maximum 24 hr. dose- 4000 mg
Timing of administration-
Not approved for children <2 yrs. of age
Give @ end of case
164
Toradol
MOA
Dose
S/E
MOA- non-selective competitive inhibition of cyclo-oxygenase (COX-1 and COX-2)
Dose- 30 mg/IV Q 6 hrs. (studies showing that 15 mg just as effective)
Reduce dose in elderly
May be contraindicated in patients with renal insufficiency & aspirin induced asthma
May prolong bleeding time**- questionable- always ask surgeon before administering
165
why do you give an anticholinergic with an anticholinesterase inhibitor during emergence?
An anticholinesterase inhibitor (like neostigmine) is used to reverse neuromuscular blockade, while an anticholinergic
(like atropine or glycopyrrolate) is given to prevent unwanted side effects of increased acetylcholine, like bradycardia and excess salivation. The two work together to safely reverse the blockade without causing parasympathetic issues.
166
what is the dose combo for neostigmine and glyco for reversal?
neostigmine (anticholinesterase)- 0.04-.08mg/kg up to 5 mg TOTAL
Glycopyrrolate- 0.2 mg IV per 1 mg Neostigmine
167
what is the reversal combo doses for neostigmine and atropine
neostigmine (anticholinesterase)- 0.04-.08mg/kg up to 5 mg TOTAL
atropine- 0.4mg/IV per 1 mg neostigmine
168
you are tring to reverse a child.... which meds do you give and in which order?
Atropine 1st!!! b/c kids rely on HR for their CO- then neostigmine (will counteract the bradycardia)
atropine- 0.04 mg/1mg Neostigmine
neostigmine- .04-.08 mg/kg/IV
169
reversal combo doses
pryidostigmine w/ atropine
pryidostigmine - .1-.25 mg/kg/IV up to 20 mg
atropine- 0.1mg IV/ 1 mg pryridostigmine
170
reversal combo doses
pryidostigmine w/ glyco
pryidostigmine - .1-.25 mg/kg/IV up to 20 mg
glyco- 0.05mg IV/1mg pyridostigmine (preferred)
171
what are side effects of anticholingerics
MUSCARINIC
Bradycardia/hypotension
bronchospasm, secretions, hypoxia
pupillary constriction (Miosis)
increase salivation, intestinal spasm, increased bladder tone
172
what is the MAC and B/G solubility coefficient of N2O?
104%
0.47
173
what is the MAC and B/G solubility coefficient for forane?
1.15%
1.4
174
what is the MAC and B/G solubility coefficient for desflurane?
6-7%
0.42
175
What is the MAC and B/G solubility coefficient for Sevoflurane?
2%
0.65
176
nondepolarizers can be prolonged/potentiated by various factors such as:
(theres 8 name a few)
volatile agents (Des>sevo>iso>n20)
antibiotics
antidysrhythmics
local anesthetics
diurietics- lasix
dantrolene/lithium
electrolytes (increased mag, hypo cal, hypokal)
hypothermia and being female
177
what will you use to reverse your nondepolarizing muscle relaxant if you don't have sugammedex?
neostigmine and robinol
178
what is the typical induction sequence?
apply monitors
preoxygenate
give fent/midaz
lidocaine prior to prop
tape eyes, mask ventilate
give roc- wait 2-3 to check TOF
turn on inhalation agent
careful intubation
