Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Pharmacology 680 > Opioid specific drugs > Flashcards

Opioid specific drugs Flashcards

(99 cards)

Start Studying
1
Q

▪ Gold standard or prototype for opioid agonists

-naturally occuring

A

morphine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

-what is duration of action for morphine and why?

A

about 4 hours
-Comparatively low lipid solubility
▪ Moves slowly across the blood brain barrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

dose of morphine for anesthetic purposes?

A

0.1 – 0.2 mg/kg used IM as

premedication and IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what mac level does morphine decrease with ceiling effect?

A

65%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

why does only <0.1% of morphine administered enter the CNS at peak plasma
concentrations? (4 reasons)

A

– Low lipid solubility
– High degree of ionization at physiologic pH
– Protein binding
– Rapid conjugation with glucuronic acid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

is morphine taken up by lungs?

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

morphine clearance?

A

Hepatic clearance is high and dependent on liver blood flow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are the two metabolites of morphine?

A

Morphine 3-glucuronide (75-85%) and

morphine 6-glucuronide (M6G) (5-10%)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Metabolites of morphine excreted..

A

renally, so renal failure causes accumulation of M6G and prolonged effect

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

in women, what are 4 differences to consider when giving morphine?

A

▪ Greater analgesic potency
▪ Slower offset
▪ No effect on apneic threshold
▪ Hypoxic sensitivity decreased

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

why should you Pretreat morphine with H1 and H2 blockers

A

histamine release is common, wont decrease the release but will block the decrease in SVR and BP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Discovered during search for synthetic atropinelike drug

A

demerol (meperidine)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Causes increase in heart rate, some large airway bronchodilation

really not used for anesthesia in adults

A

demerol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

why does demerol cause an increase in N/V?

A

Sensitizes the labyrinthine apparatus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

demerol is metabolized by demethylation in the liver to

A

normeperidine (90%) which is excreted by

the kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Dose of demerol used for peds

A

0.5 to 1 mg/kg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Normeperidine side effects

A
  • cns stimulant - seizures
  • hallucinations
  • delirium
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Meperidine duration is

A

typically 2-4 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

(Demerol dose of

> 5 mg/kg) or renal failure can cause

A

seizures

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

why does demerol suppress postoperative shivering?

A

– May represent stimulation of kappa receptors or
decreased shivering threshold
– May also be related to the alpha2 receptor stimulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q 
– Hypertension, tachycardia
– Diaphoresis, hyperthermia
– Confusion, agitation
– Neuromuscular changes – hyperreflexia
– Severe – coma, seizures, coagulopathy,
metabolic acidosis
A

Serotonin syndrome may be caused by

interaction of meperidine with MAOIs, tricyclics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Opioid designed for anesthesia

A

fentanyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

how much more potent is fentanyl than morphine?

A

100x

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

High lipid solubility of fentanyl explains

A

the rapid onset and greater potency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
clinical duration of fentanyl
20-40 minutes
26
___ initial IV dose of fentanyl is taken up by the lungs
75%
27
Repeat doses of fentanyl accumulate in
``` muscle (large compartment) and fat (high lipid solubility) ```
28
with Repeated doses or an infusion of fentanyl, drug is stored in the lungs, fat, and muscle causing
prolonged analgesia and respiratory depression
29
how is fentanyl metabolized
N-demethylation | Norfentanil most common in humans
30
3 metabolites of fentanyl
– Norfentanyl – Hydroxyproprionyl-fentanyl – Hydroxyproprionyl-norfentanyl
31
Elimination t ½ life of fentanyl is
3.1-6.6 hrs
32
Longer t ½ life of fentanyl is due to
o larger volume of distribution as fentanyl can move into tissues more rapidly than morphine.
33
what 3 reasons do the Elderly have prolonged elimination t ½ life with fentanyl?
– Decreases in hepatic blood flow – Microsomal enzyme activity – Decreases in albumin production (highly protein bound 79-87%)
34
what type of surgery is fentanyl duration prolonged with and why?
abdominal aortic surgery involving infrarenal aortic cross-clamping.
35
doses for fentanyl?
▪ 1 – 2 mcg/kg IV for analgesia | ▪ 2 – 20 mcg/kg IV as a balanced technique to blunt circulatory responses
36
dose of fentanyl that dependably blunts the sympathetic response of larygoscopy?
– 5-8 mcg/kg
37
dose of fent that significantly reduces the dose of propofol for placement of an LMA
▪ 0.5 mcg/kg
38
Large doses of fent (50-150 mcg/kg) can reduce MAC by up to
80%
39
Single dose of 3mcg/kg 25-30 minutes prior to incision can reduce iso or des MAC by
50%
40
Small doses (1mcg/kg) reduce MAC by
40%
41
Advantages of Fentanyl (3)
▪ No direct myocardial depression ▪ No histamine release ▪ Suppresses stress response to surgery
42
Disadvantages of Fentanyl
▪ Sympathetic stimulation in response to pain, especially with good LV function ▪ Unreliable amnesia ▪ Post-op respiratory depression
43
▪ Cardiovascular effects of fent
– Heart rate decreases more than morphine ▪ Occasional decreases in BP and CO – No histamine release
44
▪ Muscular effects of fent?
– Myoclonus related to depression of inhibitory neurons – seizurelike with no EEG changes
45
neuro effects of fent?
moderate increases in ICP (6-9) even | with unchanged PaCO2 bc of vasodilation and an increase in cerebral vascular resistance
46
synergist of fent?
benzos, increased resp depression | prop
47
what is a weird side effect caused by fent pre op?
reflex coughing
48
Most potent opioid currently available
sufentanil
49
what is pulmonary uptake of sufentanil?
60%
50
Elimination t ½ life sufentanil?
2.5 hours
51
Volume of distribution of sufentanil 1.17 L is smaller due to?
greater protein binding than fentanyl (92% v. 79-87%)
52
how is sufentanil metabolized?
hepatic via N-dealkylation into inactive | metabolites which are eliminated by both the liver and kidneys
53
why do we not typically use sufentanil for induction?
- stiff chest syndrome - may render patient apneic but not unconscious - glottic obstruction
54
sufentanil has a longer lasting and greater analgesic effect, what other effect is preferred
less respiratory depression
55
what can sufentanil reduce mac by
up to 70%
56
dose of sufentanil?
1/10 dose of fentanyl Fent: ▪ 1 – 2 mcg/kg IV for analgesia ▪ 2 – 20 mcg/kg IV as a balanced technique to blunt circulatory responses
57
Use of benzodiazepines along with iv infusion of sufentanil may necessitate
a decrease in dose of sufentanil - synergist
58
After infusion for 3 hours, sufentanil will decrease by
80% more rapidly than fentanyl and alfentanil.
59
After infusion for 8 hours, sufentanil will decrease by
50 % more rapidly than fentanyl or alfentanil.
60
what is sufentanils shorter context sensitive half life due to.. compared to alfent
large Vd compared to alfentanil – due to metabolism and redistribution
61
what medication is hard to detect an overdose during a case and why?
sufentanil, bp same even with 5x dose
62
why is alfentanil Volume of distribution much smaller (4-6X) than fentanyl
due to lower lipid solubility and more protein binding
63
Elimination t ½ life alfentanil
1.1-1.6 hrs
64
best choice to give for a single, brief stimulus like laryngoscopy or retrobulbar block
alfentanil
65
only 10% of alfentanil ionized at physiologic pH causes (onset alfent vs fent)
This causes faster onset or effect-site equilibration. | (A 1.4 mins; F-6.8 mins)
66
this drug is more liable to produce stiff chest and greater euphoria
alfentanil
67
Metabolism of alfentanil
n-dealkylation to noralfentanil and | amide N-dealkylation to N-phenylpropionamide
68
what makes a standard infusion and dosing regimen difficult to determine with alfentanil?
Interindividual variability related to P-450 CYP3A enzyme
69
when should alfentanil infusions be stopped?
15-25 mins before emergence
70
Direct laryngoscopy dose alfentanil
– 15 mcg/kg 90 sec before blunts SBP and HR response | – 30mcg/kg blunts catecholamine response
71
Induction dose alfentanil
– 150-300 mcg/kg given rapidly - unconsciousness
72
Infusion dose of alfentanil with inhaled agent
Infusion 25 to 150 mcg/kg/hr
73
difference in alfentanil and fentanyl with blood pressure response with dose given after stimulation
BP can be decreased with a dose of alfentanil after the | painful stimulation where fentanyl cannot
74
5X more potent than fentanyl on a mg per mg basis
remifentanil
75
Elimination t ½ time remifent
6-10 minutes
76
remifentanil Metabolized by
nonspecific plasma and tissue esterases to inactive | metabolites which are excreted by the kidneys
77
Context-sensitive half-time of remifent
Independent of infusion time – Approximately 4 minutes – Must give a longer-acting opioid to ensure analgesia when patient awakens
78
what drug from fent group has greatest decrease in bp
remifent 30% decrease in SBP two minutes after administration
79
clinical uses of remifent?
– Laryngoscopy – Retrobulbar block – Labor and delivery – Desire rapid recovery – craniotomy, carotid endarterectomy
80
what opioid has smallest Vd?
remifent so fast equilibration and fast offset
81
▪ Induction dose remifent
1 mcg/kg over 60-90 sec
82
dose if infusing remifent before iv anesthetic dose
0.5-1.0 mcg/kg over 10 minutes Then, infusion 0.05 to 2.0 mcg/kg/min IV
83
MAC (Sedation case) with remifent dose?
0.05 – 0.10 mcg/kg/min with midazolam (2 mg IV)
84
– Suggests acute opioid tolerance | – Tolerance is dose dependent
hyperalgesia | seen with remifent
85
why do Patients receiving high doses of remifentanil require high post-op analgesics
– Possibly due to alteration in NMDA receptor
86
what two things block opioid tolerance?
magnesium and ketamine
87
a decrease in the response to a drug due to its continued administration
tolerance
88
an increased response to a stimulus that is normally painful.
hyperalgesia
89
Intermediate-acting semi-synthetic opioid
dilaudid (hydromorphone)
90
what opioid is best for renal patients
dilaudid bc it lacks active metabolites
91
1.5 mg of dilaudid is equivalent to
10 mg morphine or 100 mcg fentanyl
92
dose dilaudid
0.02-0.06 mg/kg
93
onset and duration of dilaudid
Onset: 5 minutes | ▪ Duration: 4-5 hours (2-3 hrs ½ life)
94
Metabolism of dilaudid and what opioid is it similar to
mostly phase II via glucuronic acid (similar to | morphine)
95
Synthetic opioid | ▪ Useful with chronic pain
methadone
96
elimination t1/2 of methadone
35 hours
97
MOA of tramadol the centrally acting analgesic
– Inhibits reuptake of NE and serotonin and inhibits release of presynaptic release of serotonin
98
Advantages of tramadol (3)
– Treat shivering – Minimal ventilatory depressant – Less likely to cause addiction –
99
disadvantages of tramadol
– Interaction w Coumadin, ondansetron – Seizures – Nausea and vomiting -just po, iv not approved in US

Pharmacology 680 (19 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions