Propofol, Etomidate, Ketamine Flashcards
1
Q
Propofol is aqueous emulsion of what
A
10% soybean oil/propofol mix in water
- 25% glycerol
- 2% egg phosphatide
2
Q
More likely to have allergic reaction to propofol if prior reaction to what
A
Purfumes or detergents
3
Q
Effect of propofol post op in heart patients
A
Blunts post-op tachycardia and hypertension
4
Q
Propofol provides what 3
A
- control of stress response (decrease serum cortisol levels)
- anti-convulsant properties
- amnesia properties
5
Q
Does propofol have analgesic properties
A
No
6
Q
Induction drug of choice for rapid wake up
A
Propofol
7
Q
Is propofol a trigger of MH?
A
No
8
Q
Induction dose of propofol
A
1-2.5mg/kg
9
Q
Pediatric dose of propofol
A
2.5-3.5 mg/kg
10
Q
Why do children need greater induction dose of propofol?
A
Larger central distribution volumes and greater clearance rates
11
Q
Elderly induction dose of propofol?
Why?
A
25-50% less than normal
Smaller central distribution volumes and smaller clearance rates
12
Q
To avoid adverse CV effects of propofol induction dose do what
A
Give incrementally
13
Q
Concious sedation dose of propofol
A
25-300 mcg/kg/min
14
Q
Cardiac post op dose of propofol
A
25-75 mcg/kg/min
15
Q
Clearance of propofol from plasma from what?
A
Hepatic and extra-hepatic metabolism
Tissue uptake by VRG
16
Q
Hepatic metabolism of propofol is
How much excreted unchanged?
A
Rapid and extensive
0.3% excreted unchanged
17
Q
Propofol metabolites
A
Pharmacologically inactive
Water soluble Sulfate & glucuronic acid compounds excreted in urine
18
Q
Elimination 1/2 time for propofol
A
0.5-1.5 hours
19
Q
Does length of infusion of propofol effect context sensitive 1/2 time if appropriately dosed
A
No
20
Q
4 advantages of propofol
A
Easy titration
Prompt recovery
Less residual sedation
Low incidence of N&V
21
Q
Concious sedation dose provides what?
A
Minimal analgesia effects
Excellent amnesia effects
22
Q
Is elimination of propofol impaired with cirrhosis or ESRD?
A
No impairment
23
Q
In pt over 60 there is
A
Impairment of elimination
24
Q
Propofol and fetal circulation
A
Crosses placenta but rapidly cleared
25
Propofol interacts with what receptors
GABA
26
GABA receptor activation results in what (3)
1. Increased chloride conduction
2. Hyperpolarization of post-synaptic cell membranes
3. Inhibition of post-synaptic neurons
27
Sub-hypnotic dose for PONV in PACU
10-15mg
28
To tx N&V does
10mg bolus followed by 10 mcg/kg/min
29
Which drug has most rapid and complete awakening of any induction drug?
Propofol
30
Does propofol have to be given as induction drug for PONV prevention
No. Can give at any time during anesthetic
31
Propofol effect on CNS
Depresses CNS structures
Direct depressant on vomiting center
32
Propofol anti-convulsants properties due to _____
GABA mediated pre and post synaptic inhibition
33
Propofol effect on intraoccular pressure
Lowers beginning with induction and lasting through intubation
34
Propofol has anti-oxidant properties resulting in what
Neuro-protective qualities
Protective qualities against lung injury
35
Propofol and Parkinson’s tremors?
effect on anesthetic
May abolish tremors
Use cautiously in stereotactic neuro tremor ablation surgeries
36
Propofol in doses of what decrease seizure duration 35-45% in ECT patients
Greater than 1 mg/kg decrease seizure duration
37
Profound and CMRO2 requirements, CBF, ICP
Decreases all
38
Propofol and EP monitoring
Doesn’t effect EP monitoring
39
Propofol produces EEG cortical changes similar to thiopental including what
Burst suppression in high doses
40
__________ treats pruitis of neuroaxial opioids
Propofol
41
Propofol effect on BP and inotropy
Decreases BP inhibits sympathetic vasoconstrictor nerve activity
Negative inotropic effect by decreasing intracellular Calcium levels
42
Hypotensive effects of propofol are worsened in what 4 patient types
Hypovolemia
Elderly
Depressed LV function
Dehydration
43
Does HR change with propofol?
No changes to heart conduction system
44
Propofol causes what effect on ventilation
Dose dependent ventilatory depression
Apnea in 25-35% of inductions
45
Propofol on respiratory volumes
Decrease RR and TV
46
Propofol and ventilatory response to CO2 and arterial hypoxemia
Response is blunted
47
Does propofol produce bronchodilation?
YES
48
Prolonged propofol infusions may cause green urine due to what
Excreted phenols and cloudy urine from uric acid excretion
49
Does propofol adversely affect liver or kidney?
No
50
Propofol supports growth of what 2 organisms
E. Coil
Pseudomonas
51
Dispose of propofol within __________ of drawing it up
4 hours
52
Most common adverse effect with propofol
Pain on injection site
53
Etomidate is water soluble at what pH
Acidic pH
54
Etomidate is lipid soluble at what pH
Physiologic pH
55
Profound reduces ______ more than _______
SNS more than PNS
56
The first single enantiomer general anesthetic to be used clinically
Etomidate
57
Standard dose of etomidate
0.2-0.4 mg/kg
58
Etomidate concentration
2mg/ml
59
Etomidate VD is large due to what
Large tissue uptake
60
At standard doses anesthesia is induced for how long
5-10 minutes
61
1/2 of etomidate is metabolized in about _____ minutes
75 minutes
62
Etomidate is metabolized by what 2
Hepatic and plasma esterases
63
Protein binding of etomidate
76%
64
Peak brain levels of etomidate occur within
1 minute of IV administration
65
Prompt awakening with etomidate due to ______
Redistribution
66
MOA of etomidate
Enhancement of GABA
67
Frequent involuntary myoicolinc movements noted with etomidate due to what
Blunted by what
Imbalance of thalamocortical tract
blunted by opioids
68
Does etomidate have any analgesic properties
No
69
Etomidate and SSEPs
Augments amplitude of SSEPs improving monitoring
70
Can etomidate terminate status epilepticus
Yes
71
Etomidate reduces CMRO2 by what
Potent direct Cerebral vasoconstrictor
72
Etomidate and EEG
Greater frequency of excitatory spikes
73
Etomidate and epilepsy patients
Use with caution
74
Do decrease transient skeletal muscle movements
Give 0.1mg fentanyl immediately before induction
75
Drug of choice for IV induction of anesthesia with unstable CV system
Etomidate
76
CV stability with etomidate at what dose?
0.3 mg/kg
77
BP may drop 15% with etomidate 0.3mg/kg due to what
Decreased SVR
78
What is a useful induction agent when restoration of spontaneous ventilation is desirable?
Etomidate
79
Etomidate and ventilation volumes
Decreased TV offset by increased RR
80
3 adverse pulmonary effects of etomidate
Laryngospasm
Hiccups
Snoring
81
Etomidate metabolism
Hepatic and plasma esterases
82
____% of etomidate bile excretion
15
83
In pt with cirrhosis and esophageal varies, elimination 1/2 life and VD is
Doubled
84
_____% etomidate excreted in urine
85%
85
Incidence of PONV higher than propofol
Etomidate
86
Etomidate causes transient suppression of _________
Adrenocortical function
87
Adenocorticoid suppression with etomidate is desirable for what pt population?
Desired “stress free” anesthesia
88
Adrenocorticoid suppression is bad in what patient population?
Those needing preserved cortisol response (sepsis, bleeding)
89
Do Etomidate inductions significantly alter dosage requirements of NM blockers
No
90
Does etomidate cause pain with IV injection?
YES. Can be worse than propofol
91
Etomidate is relatively contraindicated in what pt population?
- PONV
- sepsis
- adrenocortical suppression
- epilepsy
- pregnancy
- infants
92
Etomidate is not used as much as propofol because of
Frequent involuntary myoclonic movements (shake and bake)
93
Drug developed as derivative of PCP
Ketamine
94
Is ketamine racemic mixture
Yes
95
Anesthesia induction dose of ketamine.
IV
IM
IV- 1-2 mg/kg
IM 4-8mg/kg
96
Subanesthetic yet analgesic dose of ketamine
0.2mg/kg
97
What aids in ketamine delivery to brain
Increases in cerebral blood flow
98
High hepatic clearance and large Vd result in elimination 1/2 time of _____ with ketamine
2-3 hours
99
Ketamine metabolism
Metabolized by hepatic microsomes enzymes (cytochrome P450) to form normketamine
100
Normketamine is ______ as potent as ketamine
20-33%
101
Rapid onset and short duration of action with ketamine is due to
High lipid solubility
102
Peak plasma concentration of ketamine occurs within _____ of IV doses
1 minute
103
Does 1 cc fentanyl have a cardiovascular effect ?
No
104
Is ketamine significantly bound to plasma proteins
No
105
Extreme lipid solubility of ketamine makes ____________ easier
Crossing of BBB
106
What produces dissociative anesthesia
Ketamine
107
Loss of conciousness occurs within _________ after IV admin of ketamine.
Conciousness returns in ______
Full orientation in ______
LOC- 30-60 seconds
Return- 10-20 minutes
Full orientation- 60-90 minutes
108
Main receptor ketamine works on
NMDA
109
Analgesia with ketamine is greater with ______ pain over ______ pain
Somatic pain > visceral pain
110
Analgesia with ketamine mediated through
Thalamus and limbic systems
111
Ketamine analgesic actions involve
Descending inhibitory monoaminergic pain pathways
112
Cheif metabolite of etomidate is
Pharmacologically inactive
113
Ketamine and anicholinergic actions result in
Bronchodilation
114
________ and ______ suggest antagonistic muscarinic receptor action with ketamine
Sympathomimetic functions and emergence delirium
115
Visual, auditory, proprioceptive, confusional hallucinations, morbid dreams, and cortical blindness with ketamine due to
Depression of inferior colliculus and medial geniculate nucleus
116
Incidence of emergence delirium with ketamine
Increased with :
Decreased with:
5-30%
Increased with >15yo, women, doses > 2mg/kg, psych illness hx
Lower with- repeated dosing, benzos 5 minute before induction
117
Etomidate and endocrine implications for infection
11 beta hydroxylase inhibition for 4-8 hours after induction
May increase infection rate
118
To reduce emergence delirium with ketamine
Give with propofol
119
Does ketamine change seizure threshold?
No
120
SSEPs and ketamine
Increased amplitude of SSEPs but less than etomidate
121
Sympathomimetic function associated with ketamine has what effect on heart
Anesthesia implications
Increases myocardial O2 needs and reduces diastolic filling of corona rise
Don’t give in pt with CAD
122
#1 mechanism for ketamine CV effects
Greater SNS outflow
123
Increased plasma concentrations of epi and NE with ketamine occur within ______ and return to normal in ______
W/i 2 minutes
Normal in 15 minutes
124
What blunts the induced CV stimulation with ketamine
Inhalation agents and benzos
125
Ketamine CV effects
Increased systemic and pulmonary BP
Increased HR
Increased CO
Greater myocardial oxygen needs
126
Ketamine is useful for asthmatic induction due to ______
Bronchodilation function
127
To decrease salivary secretion induced laryngospasm and coughing with ketamine
Give glycopyrolate
128
Why not give atropine or scopolamine for salivary secretions with ketamine?
Bc cross BBB and worsen emergence delirium
129
Ketamine and ventilation
Does not significantly depress ventilation
130
Ketamine and pulmonary HTN?
Don’t give in pt with pulmonary HTN
131
Ketamine and bronchospasm
As effective as volatile anesthesia to prevent bronchospasm
132
Ketamine and upper airway reflexes and muscle tone
Maintained
133
Ketamine is primarily metabolized
Hepatic metabolism
134
Chronic ketamine use effects
Stimulates metabolic enzyme activity.
Tolerance consistent with addiction potential
135
Long term ketamine use results in inflammation and irritation of
- biliary tract resulting in cholestatic liver injury
| - urinary bladder and urethra
136
Ketamine and GI
Well absorbed by GI tract
137
Ketamine and Succinylcholine
Enhances phase 1 and phase 2 block from succ
138
Pain on injection with ketamine?
None
139
Is there histamine release or allergic rx with ketamine
No
140
Ketamine and MAC
Decreases MAC
141
Ketamine and inotropic support requirements
Reduces inotropic support requirements
142
Epidural/intrathecal ketamine
Provide analgesia without risk of ventilatory depression
143
Which induction drug worsens elevated ICP r/t increase in CBF?
Ketamine
144
Ketamine and MH patients
Ok with MH patients
145
Ketamine acts on what receptor resulting in drooling
Muscarinic
146
Contraindication for ketamine
Systemic HTN
147
Ketamine partially antagonized by
Phyostigmine (antilerium)
