Pain Management (Meds) Flashcards
Define opioid
refers broadly to all compounds related to opium
______ is derived from greek word for stupor
Narcotic
What are the 4 classes of opioids?
- full agonists
- partial agonists
- mixed agonists - antagonists
- antagonists
What is a pro of using opioids?
have analgesic properties
What is a con of using opioids?
high potential for abuse/ addiction
Mechanism of action of opioids:
Alters the _____ & _____ aspects of pain
-opioids inhibit the transmission of ______ ______ from the ______ ______
-activates ______ pain inhibitory pathways
-alters _______ system activity
sensory & affective
-nociceptive info; spinal cord
-descending
-limbic system
Do opioids resolve all pain a patient feels?
patients typically report pain still being present, but feeling more comfortable
Where are the opioid receptors located?
dorsal horn
thalamus
cortex
What is the primary opioid pain receptor?
Mu (μ)
Mu (μ) pain receptors mediate:
analgesia
respiratory depression
euphoria
decreased GI activity
sedation
physical dependence
What are the other two opioid pain receptors?
kappa (k)
delta
Kappa (k) pain receptors mediate
some analgesia, sedation, decreased GI motility
dysphoria
What opioid pain receptors are not fully understood?
delta
Fill in the blanks with these 2 terms: (pharmacological & pharmacokinetic)
Opioids have very similar ______ effects, but significantly different ______ properties
pharmacological
pharmacokinetic
Peak times for short-acting opioids:
- oral
- IV
Oral - peak within 1 hr
IV - peak within 15 min
Pharmacokinetics of opioids:
Most opioids are readily absorbed from the ______ ______ & many other sites
GI tract
Pharmacokinetics of opioids:
Opioids are subject to _____ _____
First pass
Pharmacokinetics of opioids:
Some opioids have _____ ______
active metabolites
if these build up in the body they can actually make Sx/ pain worse
Pharmacotherapeutics of opioids:
What administration route is the MOST reliable way to achieve the therapeutic level?
Intravenously
Pharmacotherapeutics for opioids:
can have injectable but depends on muscle mass, fat, etc
hepatic metabolism
urine/ bile excretion
half life depends on the med
cross placenta/ breast milk
Full opioid agonists _____ to opioid receptors resulting in ______
bind; resulting in activation
activation of mu receptors leads to…
analgesia, respiratory depression, euphoria, & sedation
activation of the kappa receptors leads to…
analgesia, sedation & decreased GI motility
List some full opioid agonist meds
morphine
fentanyl
codeine
oxycodone
hydromorphone
meperidine
methadone
List some common side effects of full opioid agonists
respiratory depression
constipation
orthostatic hypotension
urinary retention
Full opioid agonists are ____ risk of dependence and _____ substances
high risk; controlled
What full opioid agonists is considered the GOLD standard?
Morphine
Morphine affects _____ & ______ receptors
central & peripheral receptors
it is a mu opioid agonist
What are the major side effects of morphine?
analgesia
drowsiness
mental clouding
What are other side effects caused by morphine?
respiratory depression
constipation
urinary retention
N/V
hypotension
pruritis
Morphine has active metabolites, such as _____, which can accumulate
M6-G
Morphine has multiple …
routes of administration & formulations
What full opioid agonists has essentially identical pharmacologic effects to morphine?
hydromorphone (dilaudid)
Is hydromorphone more or less potent than morphine?
more potent
Does hydromorphone (dilaudid) have active metabolites?
NO
Both morphine and hydromorphone have _____ acting forms
Short acting forms
hydromorphone has no ________ form available
Extended release
_______ extended release is available in 4 dose sizes
Oxymorphone
What can affect the absorption of extended release formulation?
Food & drinks
indications for fentanyl
surgical pre-medications (invasive procedures)
adjunct to anesthesia
breakthrough cancer pain
chronic pain
Fentanyl binds to opioid receptor sites in
CNS
What are the different routes available for fentanyl?
IV
IM
submucosal
sublingual
buccal
nasal spray
transdermal
What are some side effects of fentanyl?
confusion
H/A
sedation
bradycardia
hypotension
blurred vision
laryngospasm
constipation
respiratory depression
What full opioid agonists have numerous drug-drug interactions?
Fentanyl
Fentanyl patches should not be used for ____ pain
Acute pain
Fentanyl patches are used in patients with _______ _______ conditions
Chronic pain
How long are fentanyl patches applied for?
48-72 hrs
What should the nurse make sure of when applying a fentanyl patch?
that it is applied firmly, with no punctures or breaks in the patch
What side of a fentanyl patch is important NOT to touch
the sticky side (never touch actual medication)
Why do we need to ensure the patient is not in pain when using fentanyl patches?
they take several hours (6-12) to take effect
Where should a fentanyl patch not be placed & why?
On the chest b/c it could be placed over rib (bone) which will not absorb the medication
Why should fentanyl patches NOT be used in a patient who has a fever?
Fevers result in vasodilation of BV; increases peripheral BF and the drug is going to be absorbed faster
What skin condition can fentanyl patches cause?
Contact dermatitis
How is a fentanyl buccal “lollipop” used?
Have the pt put it in their cheek to dissolve
What full opioid agonist’s effectiveness is basically the same as ASA & acetaminophen?
Codeine
What is the major side effect of codeine?
constipation
more than any other mu agonist
About 10% of codeine is metabolized to ______ by __________ pathway
morphine; CYP 2D6
Oxycodone is available in ______ & ______ formulations
short-acting & long-acting (they are NOT the same)
Can oxycodone & oxycontin be used interchangeably?
No b/c oxycontin is LA & oxycodone is SA
What two drugs have limited usefulness?
codeine & oxycodone
Three types of hydrocodone?
vicodin
lortab
nocro
Does hydrocodone have a better or worse side effect than codeine
better
Hydrocodone is often combined with _____ or ______
acetaminophen or ibuprofen
Hydrocodone has different routes of admin & can also be used as a ______ ______
cough suppressant
What kind of onset & duration does meperidine (demerol) have?
rapid onset with short duration of action
Meperidine has ______ ______
active metabolites
Meperidine:
No evidence that efficacy enhanced by _____ or ______
Does not have a lesser effect on the _______ of ______
vistaril; phenergan
sphincter of oddi
How many mg of meperidine PO is equal to 10 mg of IV morphine?
300 mg PO = 10 mg IV morphine
What is meperidine’s limited use for?
short procedures or to treat rigors (intense shivering/ shaking w/ high fever)
tramadol (ultram, ultracet) mechanisms of action (binary)
weak mu-opioid agonist
blocks reuptake of norepinephrine & serotonin
Tramadol (ultram, ultracet)
controlled substance
analgesic ceiling higher doses do not provide additional pain relief
active metabolites
Oral route only
List some side effects of tramadol
nausea
dizziness
confusion
seizures
dry mouth
What labs should be monitored for a patient who is prescribed tramadol?
BUN/ creatinine
LFTs
think ab liver & renal function; not taking prescribed dose can cause adverse effects
Who should not be prescribed tramadol?
someone with impaired liver or kidney function
What kind of opioid receptor is methadone
mu, kappa, & delta
What medication is used to help patients withdraw from opioid abuse
methadone
Methadone decreases ______ & ______ effects of opioids
cravings & euphoric
Methadone blocks _____ receptor – decrease ______ pain threshold
NMDA receptor; CNS pain threshold
What does it mean when someone says methadone is lipophilic?
stays in the fat for a long time
What opioid is highly protein bonding
Methadone
Explain the half life & duration of methadone
long half-life (15-30 hrs), its duration of action of analgesia is up to 12 hrs
Methadone can cause prolongation of _____
Q-T wave on ECG
adverse effects:
respiratory depression
apnea
cardiac arrest
poor ventilation
adverse effects:
GI side effects
nausea/ vomiting
constipation
abdominal pain
Adverse effects:
neurologic
psychomotor & cognitive impairment
delirium
adverse effects:
histamine release
itching or flushing of the skin
List two other adverse effects
orthostatic hypotension
urinary retention
Why can opioids cause constipation?
opioids bind to receptors in the GI tract & in the CNS, which reduces bowel motility & decreases transit time
Constipation:
the decreased transit time leads to…
increased absorption of water from the stool into the intestine; causes stool to become hard, stretching of colon, & pain
What opioid side effect can you NEVER build a tolerance to?
Constipation
Contributing factors to constipation from opioids
decreased appetite
age
immobility
diabetes
other meds
What other meds contribute to constipation from opioids
antidepressants
certain chemotherapy agents
When is a PCA pump most often used?
Post-op
commonly used medications in PCA pump
morphine
fentanyl
hydromorphone
How is medication delivered through PCA pump
continuously (basal rate)
bolus (only when button is pushed)
How should a patient be monitored when using PCA pump
Closely
How do opioid agonists-antagonists bind?
bind to more than one opioid receptor site, but block other receptors
**Partially activate mu receptors; act as antagonists at other opioid receptors, such as kappa receptor **
What receptors do opioid agonists-antagonists antagonize & agonize
antagonize mu receptors & agonists to kappa receptors
List opioid agonists-antagonists medications
buprenorphine (buprenex; subutex)
pentazocine (talwin)
nalbuphine (nubain)
List the side effects of opioid agonists-antagonists
sedation
respiratory distress
constipation
may have more psychotic reactions
opioid agonists-antagonists can help relieve pain during ____ & ____
labor & delivery
Be careful to use opioid agonists-antagonists in what types of patients?
COPD patients
Pts experiencing MI or severe CAD
hepatic & renal disease
Why do we need to be careful giving opioid agonists-antagonists to patients on chronic opioid therapy for pain?
can cause withdrawal
What specific opioid agonist-antagonist medication should not be given to cardiac patients?
pentazocine (talwin)
What kind of receptor med is buprenorphine (buprenex or subutex)
partial mu agonists, but in high doses acts as an antagonist
List the different formulations of buprenorphine
injectable, IV, sublingual, nasal spray
Why is buprenorphine used in place of methadone to treat opioid addiction? List examples.
it has a long duration of effect (2-3 days)
Ex:
Subutex - only buprenorphine given sublingually
Suboxone - buprenorphine w/ naloxone (schedule III)
Is buprenorphine a high or low risk for abuse
High risk
Nalbuphine (nubain) is a mixed agonists- antagonists by
kappa receptor agonist
mu receptor antagonist
Nalbuphine is used in women experiencing labor when…
epidural anesthesia is not an option
what else is nalbuphine used for
used in anesthesia
Nalbuphine is ____ acting and lower risk of ______ _____ in both mother & baby
short acting
respiratory distress
opioid antagonists bind to
bind tightly to opioid receptors but do not activate them
What are opioid antagonists used for
to reverse opioids when levels are too high
What are two medications considered opioid antagonists?
naloxone (Narcan, Evzio)
Naltrexone (revia)
Opioid antagonists reverse what effects of opioids?
respiratory distress
hemodynamic instability
over sedation
Someone who has an opioid addiction will experience _____ when taking opioid antagonists
Withdrawal
List opioid antagonists formulations
IV
IM
Subcutaneous
nasal spray
How does naloxone (nasal spray) counteract the effects of an OD of heroin or other opioids?
naloxone has a stronger attraction to the brain’s receptors & displaces the opioids long enough to allow breathing to resume
Who should have naloxone at home?
anyone:
-taking opioids daily
-on opioids & benzodiazepines together
-chronic ETOH use
-Hx of opioid OD
-Hx of opioid addiction
-Hx of sleep apnea
-liver or kidney disease
-on methadone therapy
List the adjuvant medications (10)
NSAIDS
corticosteroids
anti-depressants
anti-convulsant
local anesthetics
muscle relaxants
alpha 2 adrenergic agonists
NMDA receptor antagonists
cannabis
hypnotics & anxiolytics
Give an example of hypnotics & anxiolytics
benzodiazepines
Cannabis is considered what schedule of controlled substance?
schedule I
but varies by state
list cannabis medications
dronabinol (marinol, syndros)
nabilone (cesamet)
cannabidiol (epidiolex)
Further research needs to be done on the correlation of cannabis use and…
increasing use in Tx of chronic pain
Cannabis has _____ & _____ properties
analgesia & anti-inflammatory properties
Does cannabis have multiple indications & routes of administration?
Yes
List side effects of cannabis
typically mild such as cough, anxiety & are well-tolerated
Why are benzodiazepines often prescribed
for Tx of pain
(evidence shows they don’t work)
Use of benzodiazepines with opioids increases risk of ______ & _______
sedation & respiratory depression
How addictive are benzodiazepines?
highly addictive
list medications considered benzodiazepines
alprazolam (xanax)
diazepam (valium)
clonazepam
lorazepam (ativan)
benzodiazepines act as an ______ of opioids
antagonist
Benzodiazepines may help with _____ Sx
withdrawal Sx
Topical agents:
Capsaicin cream
depleted substance P in primary afferent neurons
belief is that with repeated reapplication you are desensitizing the neuron
Topical agents:
How many times a day is capsaicin cream applied
3-4 times per day
Topical agents:
list side effects of capsaicin cream
burning & redness at application site
Topical agents:
EMLA cream
local anesthetic agent; inhibits depolarization of nerve & blocks neuronal firing (Blocks nerve signals that send pain to the brain)
Short term & wears off after a couple of hours
Topical agents:
How should EMLA cream be applied?
apply thick coating & cover with occlusive dressing for 1 hour
Can use when needing IV access → let cream sit for 45 min to 1 hr & it numbs area to help the pt not feel pain
Topical agents:
Lidocaine patch
local anesthetic agent; take time for effect to kick in
Available OTC
important to place patch where the pain is located
Topical agents:
How many lidocaine patches can be worn at once & for how long?
up to 3 patches at one time; may be worn up to 12 hours
Special populations & pain:
Older adults risks
respiratory depression, polypharmacy, falls
Special populations & pain:
Older adults have age-related changes in _____, _____, _____, & _____
absorption, distribution, metabolism, & elimination
Special populations & pain:
Rule of thumb for older adults & pain management
Start at a low dose & go slow
Special populations & pain:
older adults should follow routine _____ regimen
bowel regimen (i.e. drinking enough fluids; eating high fiber foods; fruits & veggies; whole grain bread, etc)
Special populations & pain:
Judicious use of opioids in what population
children & adolescents because there is little research
Special populations & pain:
What kinds of opioids should be given to children & adolescents only in life-limiting conditions?
extended-release & long-acting
Special populations & pain:
Watch for _____ in children & adolescents
diversion; illegal distribution or abuse of prescription drugs or their use for unintended purposes
Special populations & pain:
~ what % of women with childbearing potential are prescribed opioids?
~40%
Special populations & pain:
Women with childbearing potential need to be careful taking opioids as they can increase risk of ____ ____
fetal harm
most women don’t know they are pregnant in first few weeks
Special populations & pain:
As the HC team what should be done when prescribing opioids to a pregnant women?
weigh the benefits vs. risks
Special populations & pain:
Opioid use in pregnant women poses risk of
neonatal opioid withdrawal syndrome; should avoid opioids while pregnant
Special populations & pain:
What should be given to a pregnant woman already on opioids?
methadone or buprenorphine
Neurobiology of addiction:
Dopamine
Non-opioid neurotransmitter
Affect: reward, stimulation, mood
Drug–mimic neurotransmitter: cocaine, heroin, alcohol, methamphetamine
Neurobiology of addiction:
serotonin
Non-opioid neurotransmitter
Affect: mood, sleep, appetite
Drug–mimic neurotransmitter: THC, alcohol, methamphetamine
Neurobiology of addiction:
GABA (gamma-aminobutyric acid)
Non-opioid neurotransmitter
Affect: sedation, anti-anxiety
Drug–mimic neurotransmitter: alcohol, barbiturates, benzodiazepines
Neurobiology of addiction:
Norepinephrine
Non-opioid neurotransmitter
Affect: mood, sedation, constriction of BV
Drug–mimic neurotransmitter: methamphetamine
Neurobiology of addiction:
endorphins
Opioid transmitters
Affect: natural pain killers
Drug–mimic neurotransmitter: heroin, opiates, alcohol
Neurobiology of addiction:
What happens when a neurotransmitter binds to a receptor?
The site is activated with an excitatory or inhibitory effect