Induction agents cont and pain management - Quiz 3 Flashcards
1
Q
What CNS effect does etomidate provide
A
hypnosis
2
Q
Does etomidate have any analgesic properties
A
No
3
Q
What is important about the chemical structure in etomidate?
A
imidazole derivative ring
Ring only closes with a physiologic ph (8.1)
2 isomers – R+ isomer is hypnotic
4
Q
How is etomidate metabolized?
A
78% metabolized by hepatic microsomal enzymes
5
Q
Is the etomidate metabolite active or inactive?
A
Inactive
6
Q
Can etomidate accumulate?
A
Can accumulate but less of an accumulation because of its rapid clearance
7
Q
What is one of the main limiting factors to use of etomidate?
A
Transient depression of adrenocortical function.
8
Q
In transient depression of adrenocortical function, what inhibited?
A
11-betahydroxylase
Reduction of CS and mineralocorticoid production
9
Q
How long can transient depression of adrenocortical function last?
A
4-8 hrs
10
Q
After how many doses of etomidate can transient depression of adrenocortical function happen?
A
after 1 dose
11
Q
What is the MOA of etomidate?
A
Potentiation of GABAA mediated chloride shift
12
Q
What are the CNS effects of etomidate?
A
Decreased CMRO2, CBF, ICP, IOP
CPP is maintained because CO is not changed!
13
Q
What are the CV changes with etomidate in a healthy individual?
A
Minimal change in HR, BP, CVP (one of the most stable CV induction agents)
14
Q
Patient’s with aortic or mitral valvular disease may experience what with etomidate?
A
significant decrease in systemic BP, PAP, PCWP.
15
Q
Respiratory effects of etomidate
A
decrease in minute volume and response to C)2 accumulation.
Brief periods of apnea followed by hyperventilation.
16
Q
Does etomidate increase or decrease incidence of PONV?
A
Increase
17
Q
Etomidate has a lower incidence of true allergic reaction, what could this be from?
A
No histamine release
18
Q
MOA of precedex
A
Highly selective α2-adrenergic agonist
19
Q
What is the active component of precedex
A
D-isomer of medetomidine
20
Q
Alpha 2 receptors in the CNS have what in regards to releasing norepinephrine?
A
negative feedback loop
21
Q
How is precedex bounds?
A
highly protein bound
22
Q
How is precedex metabolized?
A
Rapidly metabolized by hepatic microsomal enzymes
23
Q
how is precedex excreted?
A
Metabolites excreted in urine and bile
24
Q
How do you awaken from precedex?
A
naturally and easily
25
hypnosis from precedex occurs how?
from stimulation of α2 receptor at locus ceruleus.
26
Where does analgesia effects from precedex originate?
at the level of the spinal cord
27
How do sedative effects work with precedex?
activates endogenous sleep pathways
28
Does precedex have a potential for tolerance?
yes - negative feedback loop
29
What should be your maximum length of time for precedex gtt?
24 hours. It is causing long term suppression of sympathetic nervous system
30
CNS effects of precedex
Decrease in CBF
No change in CMRO2 / ICP
31
does precedex increase or decrease in MAC requirement for inhaled anesthetics
Decrease
32
True to False, precedex causes a decrease in anesthetic requirement for opioid
True
33
CV affects from precedex
Moderate decrease in heart rate and SVR
34
What are the respiratory effects from precedex?
minimal changes
35
Why don't you see many respiratory effects from precdex?
Norepi does not have significant beta 2 effects (bronchodilator, bronchoconstriction) This is why you don’t see many respiratory effects from precedex.
36
What is neuropathic pain and how is it described by patients?
No physical injury but nerve is firing inappropriately
Burning, electric shock, lightening bolt
37
What is nociceptive pain and how is it described by patients?
Any pain that has happened to body structure
Stabbing, pressure, sharp, dull, achy
38
Will opiates help with neuropathic pain?
No, never
39
Nociceptive pain must have what in order to send pain signals to spinal cord?
Stimulation
40
In neuropathic pain, do you need to have a stimulus?
NO, sometime you do (pinched nerve) but you DO NOT need to have one
41
In nociceptive pain, what is transmission?
Action potential moves from site of stimulus to the dorsal horn of the spinal cord, then to the CNS.
There are several pathways
42
In nociceptive transmission, what type of pain does A delta fibers transmit?
sharp localized pain
43
In nociceptive transmission, what type of pain does C fibers transmit?
dull/ achy pain, poorly localized
44
Calcitonin related peptides are now being targeted for what?
New migraine medications
45
In nociceptive pain, what is perception?
Conscious experience of pain
Pain impulse relayed through thalamus
Higher cortical structures transmit pain
46
In nociceptive pain, what is modulation?
Inhibition of impulses via the brain stem.
47
Neuropathic pain is sustained by what?
abnormal processing of sensory input
Nerve damage, persistent stimulation, autonomic dysfunction
48
What is hyperalgesia
abnormally heightened sensitivity to pain
49
What is allodynia?
pain resulting from a stimulus, such as light touch, which would not normally provoke pain
50
How do you differentiate acute vs chronic pain?
Chronic Pain >3 months OR past the time of normal tissue healing
51
How many patients presenting to physician offices with noncancer pain symptoms or pain-related diagnoses received and opopioidiod prescription?
1/5 or 20%
52
What is the PQRST monitoring of pain?
```
P: palliative and provocative factors
Q: Quality
R: Radiation
S: Severity
T: Temporal relations
```
53
Besides the pt telling you they are in pain, what else could you look for?
Grimacing, guarding, sweating, nausea
Hypertension, tachycardia, tachypnea
54
People who use opiates for > 5 days, have an exponential increase at still using that medication at ______ days
30
55
6% of patients s/p elective surgery (minor or major, all types) continue to use opiates for at least ____ days
90
56
The GREATEST percentage (44%) of people dying of opioid overdose is
middle age 45-64 years old
57
Which groups of people are at risk for inadequate pain control
```
Racial and ethnic minority groups
Women
Elderly
Persons with cognitive impairment
Cancer and at the end of life
```
58
The optimal length of opioid prescriptions for
General surgery
Womens health
Musculoskeletal
General surgery 4-9 days
Womens health 4-13 days
Musculoskelatal 6-15 days
59
Where are opioid receptors located?
Located throughout the brain, spinal cord, GI tract
60
What are the 4 subtypes of opiod receptors?
Delta
Kappa
Mu
Nociceptive
61
Where are the delta opioid receptors and what are they responsible for?
Brain and peripheral nerves
Analgesia, antidepressant, DEPENDENCE
62
Where are the kappa opioid receptors and what are they responsible for?
Brain, spinal cord, periphery
Analgesia, sedation, miosis, dysphoria, ADH inhibition (urinary hesitancy)
63
Where are the Mu opioid receptors and what are they responsible for?
Brain, spinal cord, periphery, intestine
Mu1: analgesia, dependence
Mu2: respiratory depression, euphoria, reduced GI motility, dependence, constipation
Mu3: unknown
64
Where are the nociceptive opioid receptors and what are they responsible for?
Brain, spinal cord
Anxiety, depression, appetite, tolerance to mu agonists
65
What is andenylate cyclase
an enzyme that takes ATP and changes it to cyclic AMP
66
How do opiates respond to Mu receptors?
in an inhibitory way.
Morhine stops cAMP, By morphine binding, it reduces the amount of Ca that is coming in, so it reduces the amount of neurotransmitter that are being released, stopping the signal.
67
Opioid stimulation of the NMDA receptor may cause what in regards to opioid effectiveness?
reduced opioid effectiveness
68
Overstimulation by glutamate may be the cause to?
Neuropathic pain
69
What is our natural opiate?
Morphine
70
What are some examples of our semisynthetic opiates?
dilaudid, fentanyl
71
What plant does morphone come from and where is it grown?
Comes from the poppy plant – majority plants grown in Afghanistan
72
Our S anteomere and only levo-rotatory forms of opioid have
agonistic activity
73
Opioids must exist in the ______ state in order to form a strong bond at the opioid receptor.
Ionized
74
Of the opioids, which is the most ionized?
Morphine
75
What routes can you give morhine?
PO, IM, IV, SQ, IT, Epidural
76
What effects does morphine provide?
analgesia, sedation, and euphoria
77
How does morphine change the threshold of pain?
Increases the pain threshold and modifies the perception of noxious stimuli so that it is no longer experienced as pain.
78
What type of pain is relieved the best by morphine?
Continuous dull pain is relieved more effectively than intermittent sharp pain.
79
When does morphine peak?
15-30 minutes
80
How much IV morphine enters the CNS?
<0.1%
| binding is mostly along spinal cord on dorsal horn peripherally
81
Morphine creates 2 metabolites, what is the M3G metabolite?
inactive
| (bulk of metabolite) 75-85%
82
Morphine creates 2 metabolites, what is the M6G metabolite?
active
5-10%
Inside the CNS M6G is 100x more potent than morphine.
(The hydrophilicity of M6G normally prevents its entrance to the CNS. HOWEVER, Chronic administration or renal failure can cause M6G to enter the CNS by mass action.)
83
What is the biggest reason people die of opiate overdose
respiratory depression
84
When we give morphine, suppression of sympathetic nervous system and vasodilation
hypotension, bradycardia
85
Morphine causes a histamine release which leads to what?
Itching
| vasodilation- hypotension
86
Which opioid agonist produce dose dependent & gender specific depression of ventilation.
ALL of them
Women seem to have higher risk (unsure why)
87
What does rapid injection of morphine cause?
chest wall rigidity - can make intubation difficult
88
Why do we need to use caution when administering morphine to its with head injuries?
causes an increase in ICP
89
Morphine causes pupil
constriction
90
effects of morphine on an EEG
Resembles sleep associated change
91
Explain sedation and pain control of morphine
People will feel tired and lethargic before they feel pain control
92
What is the side effect of morphine in the biliary system?
May cause spasm of biliary smooth muscle.
During cholecystectomy – opioid induced spasm of the sphincter of oddi
93
What is the treatment for biliary spasms caused by morphine?
glucagon
it increases amount of cAMP
94
When does opiate induced constipation go away?
never, PREVENTION is key
95
Genitourinary side effects of morphine
hesitancy
96
Does morphine have any effect on neuromuscular blocking agents?
No
97
Patients on MAO inhibitors may experience _______ CNS depression and hyperpyrexia after an opioid agonist (esp demerol)
exaggerated
98
In comparison to morphine, what is different about dilaudid?
Semisynthetic
More potent
Does NOT have an active metabolite
99
Fentanyl is a ______ agonist
synthetic
100
Fentanyl analgesia is _______ times more potent than morphine
75-100
101
Single dose fentanyl demonstrates more rapid _____ and _____ duration of action than morphine
Onset
| Shorter
102
Fentanyl effect-site equilibration time between blood and brain is about ___ minutes
6
103
Is fentanyl more hydrophilic or lipophilic than morphine
lipophilic
More rapid onset
Greater potency
Greater passage across BBB
104
Why does first dose of fentanyl wear off
d/t redistribution, not from clearance
105
The ____ serve as a large inactive storage site with an estimated 75% of a single fentanyl dose undergoing 1st pass pulmonary reuptake
Lungs
106
Fentanyls metabolite is ______, and can be detected in urine for up ______
Inactive
| 72 hrs
107
does fentanyl increase ICP
yes, modest increase 6-9 mmHg
108
CV effects from fentanyl
Bradycardia, hypotension, decreased CO (from reduced SNS stimulation NOT histamine release)
109
Does fentanyl release histamine?
NO
110
When you take opiates and benzos, what is the effect?
exponential/synergistic effects when it comes to hypnotic effects, depression and ventilation
you should does at least 2 hours apart
111
What might you have to do an opiate dose if pt is on cardiopulmonary bypass? esp fentanyl
increase the dose, a significant portion of the drug adheres to the circuit of the cardiopulmonary bypass circuit.
112
What are the different fentanyl routes?
Intrathecal, Oral transmucosal fentanyl - “oralet", patch
113
When you take off a fentanyl patch, how much medication is still left on the patch?
approx 90%
114
What allows for fentanyl to be used by other routes?
Its lipophallicity
115
Sufentani is _______ times more potent than fentanyl and _______ times more potent that morphine
5-10
1000
116
What is the SL form of sufentanil?
Dsuvia
117
Elimination time for Sufentanil is
intermediate
Fentanyl>sufentanil>alfentanil
118
Is elimination of Sufentanil effected by liver disease?
No
119
Sufentanil Vd and elimination half-time is increased in obese patients due to
high lipid solubility
120
How much first pass pulmonary reuptake does Sufentinal go though?
60%
121
Is sufentanils metabolite active or inactive?
inactive
122
How is sufentanil eliminated?
Less than 1% is excreted unchanged in the urine
Normal renal function is important for elimination of sufentanil
Patients with chronic renal failure may have prolonged depression of ventilation and abnormally high plasma concentrations of sufentanil
123
Does Sufentanil have an increase or decrease in CMRO2 and CBF
decrease
124
CV effects of Sufentanil
Bradycardia
| Decreased CO, secondary to bradycardia
125
Why would you use Sufentanil or fentanyl?
When there is a shortage of fentanyl
126
Alfentanil is ______ the potency of fentanyl
1/5 - 1/10
127
Alfentanil is ______ the duration of action of fentanyl
1/3
128
What is the unique advantage about its rapid effect-site equilibration time.
Even MORE rapid onset of action
Alfentanil 1.4 minutes
Fentanyl 6.8 minutes
Sufentanil 6.2 minutes
129
The short elimination half-time if alfentanil makes it useful for what?
useful drug for quick, single, brief stimulus procedure.
130
How is alfentanil metabolized?
Highly dependent on the liver
131
Why is alfentanil different from other fentanyl products?
quicker onset and quicker clearance
132
Remifentanil is similar to _______ for quick site equilibrium
Alfentanil
133
How is remifentanil metabolized?
by esterases to inactive metabolites
134
how fast is remifental metabolized?
6 minutes or less
135
Why does remifentanil have more mild effects?
it is metabolized so fast it does not have time to get into conduction pathways
136
If you use this medication during a procedure, what might happen post-op?
This medication is metabolized so quick that the pt will probably need additional pain medication.
