Opioid and non opioid analgesics Flashcards
1
Q
What is allodynia
A
Reduced threshold to pain
2
Q
What is hyperalgesia
A
Increased response to pain stimulus
3
Q
What is transduction
A
Transducing an action potential in response to chemicals/immune cells/pro-inflammatory compounds released from injured tissue
4
Q
Drugs that target transduction
A
NSAIDs
LA
Steroids
Antihistamines
Opioids
5
Q
What is transmission?
A
Pain signal relayed through 3 neuron afferent pathway along spinothalmic tract
6
Q
3 neurons of spinothalmic tract
A
- First order
- Second order
- Third order
7
Q
Where does the first order neuron extend to?
A
Periphery –> dorsal horn
8
Q
Where does the second order neuron extend to?
A
Dorsal horn –> thalamus
9
Q
Where does the third order neuron extend to?
A
Thalamus –> cerebral cortex
10
Q
Which drugs target transmission?
A
LA
11
Q
What is modulation?
A
When pain signal is modified (inhibited or augmented)
12
Q
Most important site of modulation
A
Substantia gelatinosa in the dorsal horn (Rexed lamina 2 and 3)
13
Q
The descending inhibitory pathway begins in the ____ and ____. It projects into the substantia gelatinosa
A
periaquaductal gray
rostroventral medulla
14
Q
Drugs that target perception
A
GA
Opiods
Alpha 2 agonists
15
Q
What kind of -R are opioid -R?
A
GPCR
16
Q
4 kinds of opioid R
A
mu
delta
kappa
ORL-1
17
Q
Where are opioid -R located?
A
Brain
SC
Peripheral
18
Q
3 sites of opioid -R in the brain
A
Periaqueductal gray
locus coeruleus
rostral ventral medulla
19
Q
Site of opioid-R in the SC
A
dorsal horn
20
Q
Which endogenous opioid bind to the MU-R?
A
Endorphins
21
Q
Which endogenous opioid bind to the Delta-R?
A
Enkephalins
22
Q
Which endogenous opioid bind to the Kappa-R?
A
Dynorphins
23
Q
Which opioid -R stimulation leads to bradycardia
A
Mu
24
Q
Which opioid -R stimulation leads to Euphoria
A
Mu
25
Which opioid -R stimulation leads to mild hypothermia
Mu
26
Which opioid -R stimulation leads to prolactin release
Mu
27
Which opioid -R stimulation leads to miosis
Mu
Kappa
28
Which opioid -R stimulation leads to urinary retention. Diuresis?
Mu
Delta
Kappa
29
Which opioid -R stimulation leads to N/V
Mu
30
Which opioid -R stimulation leads to pruritis
Mu
Delta
31
Which opioid -R stimulation leads to dysphoria, hallucinations, delirium?
kappa
32
What differences are associated with Women receiving Morphine vs. men?
Greater potency in F
Slower onset in M
Longer DOA in F
Lower post op opioid consumption in F
33
What do opioids do to ventilatory response to CO2
Decrease
34
Which way is CO2 response curve shifted when opioids are used
To the right
35
What happens to RR and Vt when opioids are used?
RR decreased
Vt increased
36
What happens to ICP with opioid use
Increases if ventilation is not maintained
37
Pupil constriction occurs due to PNS stimulation of __ and __ due to Edinger Westphal nucleus stimulation
ciliary ganglion
occulomotor n. (CN 3)
38
What area is triggered to lead to NV with opioid use?
Chemo-R trigger zone
39
Do opioids effect SSEP?
Minimally
40
What effect do opioids have on heart rate?
Bradycardia
41
In healthy pts, what is effect of opioid on BP?
Minimal effect
42
Which 3 opioids can release Histamine and therefore lead to hypotension?
Morphine
Meperidine
Codeine
43
Vasodilation with opioids is _
Dose dependent
44
Is myocardial depression caused by opioids?
No unless used with N2O
45
Opioids affect gastric emptying how?
Decrease it!
*Keep this in mind if your patient is on chronic opioids
46
Opioids cause contraction of sphincter of _ which increases biliary P. How is it resolved?
Oddi
Glucagon
Narcan
47
Which muscle is relaxed when it needs to be contracted to allow for urination? Occurs with opioid use
Detrusor
48
Not only do VA cause vasodilation which can drop body temp during sx, but opioids can cause hypothermia as well. How?
Reset hypothalamic set point
49
Opioids can be classified as naturally occuring, semi-synthetic, or __
synthetic
50
Subtype of naturally occurring opioid
Phenathrene derivative
51
What opioids are naturally occuring?
Morphine
Codeine (prodrug that produces Morphine)
52
2 subtype classes of semisynthetic opioids? What drugs fall in them?
Morphine derivatives: Dilaudid, Heroin, Naloxone, Naltrexone
Thebaine derivatives: Oxycodone
53
3 subtypes of synthetic opioids. What drugs fall under them?
Piperidine: Miperidine
Phenylpiperidines: Fent, Sufent, Remifent, Alfent
Diphenylpropylamines
54
What is the standard by which all other opioids are compared?
Morphine 10 mg IV
55
How much Meperidine would you give to equate to 10 mg Morphine?
100 mg
56
How much Dilaudid would you give to equate to 10 mg Morphine?
1.5 mg
57
How much Alfentanil would you give to equate to 10 mg Morphine?
1000 mcg
58
How much Remifent would you give to equate to 10 mg Morphine?
100 mcg
59
How much Fent would you give to equate to 10 mg Morphine?
100 mcg
60
How much Sufentanil is needed to achieve an equivalent dose of 10 mg Morphine?
10 mcg
61
What is dependence of opioids?
When a person will withdraw if they stop taking the drug
62
What is tolerance of opioids?
Pt requires a higher dose of a drug to achieve a given effect
63
What is addiction
A disease. Despite negative effects of taking the drug, they continue to do so
64
Tolerance develops to nearly all side effects of opioids except???
Miosis
Constipation
65
Early S/S of opioid withdrawal?
Diaphoresis, insomnia, restelessness
66
Late S/S of opioid withdrawal?
Abdominal cramping, N/V
67
Onset of Fent and Meperidine withdrawal?
2-6 hours
68
When does Fentanyl and Meperidine withdrawal occur?
6-12 hours
69
Duration of Fentanyl and Meperidine withdrawal?
4-5 days
70
Onset of Morphine and heroin withdrawal?
6-18 hours
71
Peak of Morphine and Heroin withdrawal?
36-72 hours
72
Onset of Methadone withdrawal?
24-48 hr
73
Peak of Methadone withdrawal?
3-21 days
74
Duration of Methadone withdrawal?
6-7 weeks
75
Which opioids produce an active metabolite?
The M drugs
Morphine
Meperidine
76
Morphine is conjugated to which 2 metabolites?
Morphine 3 glucuronide (inactive)
Morphine 6 glucuronide (active)
77
Why do we have to be careful about Morphine administration with renal failure?
The active metabolite morphine 6 glucuronide can build up leading to respiratory depression
78
Metabolite of Meperidine. Active or inactive?
Normeperidine
1/2 as potent as its parent compound
79
What can Meperidine cause?
Seizures
80
Who should we avoid giving Meperidine to?
Renal failure pts on HD and elderly because the metabolite will build up
81
In what way is Remi metabolized?
tissue esterases
82
how should you dose your Remifentanil
off lean body weight
83
Which -R does Meperidine stimulate?
Mu
Kappa
84
Can you use Meperidine on the PCA? Why or why not
No
It has an active metabolite than can cause seizures
85
Not only does Meperidine stimulate Mu and Kappa -R, it also increases levels of ___
Serotonin! Weak serotonin reuptake inhibitor
*If given with MAOIs --> seratonin syndrome
86
Why does Meperidine cause anticholinergic effects?
Structurally similar to Atropine
87
Stimulation of what -R leads to decrease in post-op shivering?
Kappa
88
At 7.4 pH, how much Alfentanil is non-ionized and how much is ionized?
90% non ionized
10% ionized
89
Which opioid has highest % nonionized amount?
90. Alfentanil
90
Which opioid has least amount of non ionized drug?
Meperidine (Demerol)
91
Alfentanil is metabolized by:
The liver
92
Which drug inhibits Alfentanils metabolism?
Erythromycin!
*Can prolong respiratory depression
93
What -R does Remi stimulate?
Mu
94
Maintenance infusion dose of Remi?
0.1-1.0 mcg/kg/min
95
Context sensitive half time of Remi regardless of infusion time?
4 min
96
Why is Remi's context sensitive 1/2 time 4 min regardless of how long the infusion was on?
It is rapidly metabolized by tissue cholinesterases
97
What can the use of Remi do to post op pain?
Opioid Induced Hyperalgesia
98
3 mechanisms of Methadone
Mu-R angonist
NMDA-R antagonist
Inhibits reuptake of monoamines in the synaptic cleft
99
What changes may you see on the EKG due to Methadone?
QT prolongation
Torsades
100
Stimulation of which -R is thought to contribute to sk.m. rigidity with the use of opioids?
-mu
101
What is the best tx for opioid rigidity?
Paralysis and intubation
102
MOA of Buprenorphine
Mu agonist (partial)
103
MOA of Nalbuphine
Kappa agonist
Mu antagonist
104
MOA of Butorphanol
Kappa agonist
Mu antagonist (weak)
105
Which 2 partial agonists have greater analgesia compared to Morphine?
Buprenorphine
Butorphanol
106
Which partial agonist opioid is difficult to reverse with Naloxone and why?
Buprenorphine
Has a high affinity for mu -R
107
Which partial agonists can be reversed with Narcan?
Nalbuphine
Butorphanol
108
Best partial agonist opioid with heart disease because it does not cause cardiac changes
Nalbuphine
109
Best partial agonist for post op shivering
Butorphanol
110
Which -R does Narcan antagonize? Which one the most?
Mu (most)
Delta
Kappa
111
Narcan dose:
1-4 mcg/kg
It is better to give 20-40 mcg at a time
112
Duration of Narcan
30-45 min
113
Where is metabolism of Narcan
Liver
114
You do not want to overdo the dose of Narcan in a patient with severe pain because it can lead to_
neurogenic pulmonary edema, tachycardia, cardiac dysrhythmia, sudden death
115
Naloxone undergoes significant first pass metabolism, which drug i s similar but undergoes less first metabolism
Naltrexone
116
What is special about Methylnaltrexone
It does not x the BBB, so it will not reverse respiratory depression but it will reverse peripheral effects like bowel dysfxn
117
Which opioid antagonists lasts the LONGEST?
Naltrexone: up to 24 hr
118
Biggest concern surrounding basal rate of opioid on PCA pump?
Respiratory depression. Not routinely used for post op patients for this reason
119
What level of care should the patient have when on a PCA??
Intermediate or ICU
120
