Pain Flashcards
(121 cards)
1
Q
what non-pharmacological techniques can we use for pain?
A
- decrease inflammation and sensation with ice
- alleviate the trigger at the nociceptors with massage and physio
- distractions and behaviour modulations (CBT)
2
Q
define visceral pain
A
deep, organ related pain
3
Q
define cutaneous pain
A
superficial, surface related pain
4
Q
define referred pain
A
pain in an area due to body surfaces innervated by the same spinal nerve/nerve plexus and interneuron communication
5
Q
define neuropathic pain
A
persistent nerve irritation
6
Q
define allodynia
A
pain caused by a non-painful stimulus
7
Q
define hyperalgesia
A
hypersensitivity to a painful stimulus
8
Q
define paresthesia
A
pins and needles pain
9
Q
define phantom pain
A
neuropathic pain post amputation
10
Q
how does phantom pain occur?
A
Spinal cord neurons are still active despite lack of stimulus and interneurons continue to communicate pain
11
Q
define dermatomes
A
cutaneous segments serviced by the same spinal nerve
12
Q
define acute pain
A
pain that lasts <10 days
13
Q
define chronic pain
A
pain that lasts > 6 months
14
Q
chronic pain signals likely travel along which fibers?
A
C fibres - hence slow pain
15
Q
define nociceptors
A
receptors that sense pain
16
Q
what sensory tract carries pain sensation?
A
spinothalamic tract
17
Q
what fiber does fast pain travel through?
A
A fibers
18
Q
what fiber does slow pain travel through?
A
C fibers
19
Q
what are the endogenous opioid peptides?
A
- endorphins
- enkephalins
- dynorphins
20
Q
what is the function of endogenous opioid peptides?
A
inhibit release of substance P
21
Q
what structures are serotonin and norepinephrine released by?
A
- hypothalamus
- limbic system
- reticular formation
22
Q
what is the function of serotonin and norepinephrine regarding pain and how do they carry out their function?
A
inhibit release of substance P by binding opioid receptors
23
Q
what is the pain gate theory?
A
pain signals can be interrupted in the substantia gelatinosa of the spinal cord, which acts as a “gate”
24
Q
define opium
A
naturally occurring milky extract from the unripe seeds of the poppy plant
25
define opiates
naturally occurring chemical compounds extracted from opium
26
define opioids
any drug that is derived from the opium formula, synthetic or natural
27
define narcotics
morphine like drugs that produce analgesia and CNS depression
28
what is the purpose of opioids?
Remain therapeutic mainstay for moderate to severe pain management
29
what is the titration principle of opioids?
they have no ceiling dose and can be titrated upwards as needed and titrated downwards as soon as a patient can tolerate
30
what is the scheduling of opioids?
most are schedule I with some schedule II
31
what is the mechanism of action of opioids?
agonists for receptors **mu 1 & 2, kappa,** delta, sigma, epsilon to inhibit release of substance P
32
what are the pain neurotransmitters?
* **substance P**
* glutamate
33
which areas of the body do opioids distribute to?
* skeletal muscle
* liver
* kidneys
* lungs
* intestinal tract
* spleen
* brain
34
what is the PPB percentage of opioids?
20-35% PPB
35
how long does it take opioids to reach peak plasma concentration when administered via PO?
1 hour
36
how long does it take opioids to reach peak plasma concentration when administered via IV?
20 mins
37
what effects does opioid binding at the mu1 receptor have?
* analgesia
* euphoria
* confusion
* dizziness
* nausea
* sedation
* histamine and dopamine release
38
what effects does opioid binding at the mu2 receptor have?
* respiration depression
* cardiovascular effects (hypotension)
* GI effects (slow motility)
* urinary retention
* miosis
39
what effects does opioid binding at the delta receptor have?
* analgesia
* cardiovascular effects
* respiratory depression
40
what effects does opioid binding at the kappa receptor have?
* analgesia
* psychomimetic effects (nightmares)
41
name examples of high efficacy opioids
* fentanyl
* hydromorphone
* meperidine
* morphine
* methadone
42
in which situation is methadone the opioid used?
for opioid addictions and chronic pain
43
in which situations is hydromorphone used?
for post op or for cancer related pains
44
what is a possible adverse effect of meperidine?
seizures if used long term
45
name examples of moderate efficacy opioids
* hydrocodone
* oxycodone
* oxycontin
* tramadol
* codeine
46
what are some risks of using codeine?
risk for respiratory depression and toxicity
47
what is a benefit of combination drugs?
cause an added, synergistic effect while reducing dependance on opioids
48
percocet is a combination of which drugs?
oxycodone and acetaminophen
49
percodan is a combination of which drugs?
oxycodone and ASA
50
vicodin is a combination of which drugs?
hydrocodone and acetaminophen
51
tramacet is a combination of which drugs?
tramadol and acetaminophen
52
atasol is a combination of which drugs?
acetaminophen, caffeine and codeine
53
tylenol #1-#4 is a combination of which drugs?
acetaminophen and codeine
| #1 has the least amount of codeine and so forth
54
what drug class does morphine belong to?
opioid analgesics and opiate receptor agonist
55
what is morphine's mechanism of action?
bind to opiate receptors and act as agonists of endogenous opioids to reduce perception of and response to pain
56
what are contraindictions of morphine use?
* hypersensitivity to drug
* severe respiratory disease
* head injury
57
what are some adverse side effects of morphine?
* severe respiratory/CNS depression
* constipation
* urinary retention
* pruritis
58
what drug class does naloxone belong to?
opioid antidote (antagonist)
59
what is a contraindiction of naloxone use?
hypersensitivity to the drug
60
what is an adverse/common side effect of naloxone use?
ventricular arrythmia
61
what is an indication that naloxone should be used?
respiratory or CNS depression - if RR falls below 8-10 breaths/min and client has altered mental status
62
what is the mechanism of action of naloxone?
antagonism - blocks opioids from binding at mu and kappa receptors
63
what medication is typically administered for <4/10 pain level?
non opioid medications such as analgesics like NSAID's, Tylenol via less invasive routes (e.g. PO)
64
what medication is typically administered for 4-6/10 pain level?
use moderate efficacy opioids, combination drugs or Morphine (gold standard)
65
what medication is typically administered for >6/10 pain level?
use higher potency opioids, consider using IV route or PCA
66
what is patient controlled analgesia?
a programmable syringe pump that allows the patient some control to deliver opioid infusions with individualized settings
67
define formulations
different preparations of a drug for different administration routes
68
define synergy
the interaction of 2 or more drugs when their combined effect is greater than the sum of the effects seen when each drug is given alone
69
what drugs can we use to treat pain at the PNS level?
* NSAIDs
* glucocorticoids
70
what drugs can we use to treat pain at the CNS level?
* opioids
* tylenol
71
what is menthol's mechanism of action?
activate cold-sensing receptors to "close the gate" of pain
72
how does menthol act on the pain gate theory?
cold sensations travel down free nerve endings and synapse with inhibitory interneurons in the dorsal gray to override pain impulses
73
what are some drugs acetaminophen can be combined with?
* opioids
* antihistamines
* antitussives
* andrenergic agonists
* muscle relaxants
74
what is the mechanism of action of antitussives?
CNS depression of the cough reflex
75
what is the mechanism of adrenergic agonists?
have a sympathomimetic effect to decrease nasal secretions and cause vasoconstriction
76
what are some antitussive drugs that can be combined with acetaminophen?
* codeine
* hydrocodone
* dextromethorphan (Robitusan)
77
what are some adrenergic agonist drugs that can be combined with acetaminophen?
* ephedrine
* pseudoephedrine
* phenylephrine
78
what is the mechanism of action of methocarbamol?
it is unclear but labelled as a CNS depressant
79
what are antitussives used for?
anti cough treatment
80
what are adrenergic agonists used for?
for congestion treatment
81
what is methocarbamol used for?
as a muscle relaxant
82
Robaxacet is a combination of which drugs?
methocarbamol and acetaminophen
83
Robaxisal is a combination of which drugs?
acetylsalicylic acid (ASA) and methacarbamol
84
what drug differentiates Benylin and Benylin night?
Benylin night contains a 1st generation antihistimane, causing the sleepiness
85
what are some theories regarding the MOA of acetaminophen as an analgesic?
* interferes with prostaglandins but not at the peripheral level (therefore not anti-inflammatory)
* agonizes cannabinoid receptors
86
what is the cough reflex?
an innate, protective mechanism to clear mucus or infectious processes
87
how is the cough reflex transmitted?
mechano/chemoreceptors in the upper/lower airways send afferent impulses to the cough center in the medulla, the medulla then sends efferent impulses to the diaphragm/lungs/intercostals to cough
88
define exogenous pyrogens
bacteria produced pyrogens that trigger fever response
| e.g. endotoxins
89
define endogenous pyrogens
body produced inflammatory mediators that trigger fever response
| e.g. cytokines
90
what are some effects caused by the high temperature of fever?
* increases basal metabolic rate
* decreases cellular fxn
* causes discomfort
91
what is the treatment for fever?
antipyretic drugs
92
what are some examples of antipyretic drugs?
* acetaminophen (Tylenol)
* NSAIDs (Ibuprofen, ASA)
93
what is the MOA of acetaminophen as an antipyretic?
induces hypothalamic-peripheral vasodilation by inhibiting PGE2 → heat loss
94
what is the MOA of NSAIDs as an antipyretic?
Anti-inflammatories reduce cytokines → decreased pyrogenic stimuli
95
what are the 4 C's of psychological addiction?
* **C**ravings
* **C**ompulsion to use
* Loss of **C**ontrol
* Use despite harmful **C**onsequences
96
what is the treatment for physical addiction to drugs?
weaning protocols
97
what is complex regional pain syndrome (CRPS)?
a neurological condition that causes chronic pain
98
what are symptoms of CRPS?
* skin changes to injured area
* muscle and/or joint stiffness
99
how is the SNS affected to cause chronic pain?
pain impulses trigger repetitive and altered SNS responses, leading to chronic inflammation and chronic pain cycle
100
how does the SNS response differ from acute pain to chronic pain?
chronic pain SNS responses don't involve tachycardia, tachypnea or vasoconstriction like acute pain, instead it activates the inflammatory cascade
101
what is the treatment of chronic pain?
* counselling
* physiotherepy
* treatment of cause
* CNS drugs
102
how does Gabapentin (Gaborone) work to treat chronic pain?
decreases excitatory neurotransmitters, decreasing abnormal pain in the CNS
103
how do NMDA antagonists work to treat chronic pain?
receptor binds glutamate, decreasing the excitatory neurotransmitter in the CNS
104
how do SSRIs treat chronic pain?
increase serotonin, which combats pain
105
what is an advese side effect of enhancing serotonin?
serotonin syndrom (excess serotonin) can cause high fever, diaphoresis, tachycardia and hypertension
106
what side effects do opioids have on the CNS?
* CNS depression
* excessive sedation or unresponsiveness
107
what side effects do opioids have on the respiratory system?
* respiratory depression
* apnea
108
what side effects do opioids have on the cardiovascular system?
* bradycardia
* hypotension
109
what side effects do opioids have on the GI system?
* constipation
* nausea, vomiting
* reduced appetite
110
what side effects do opioids have on the genitorurinary system?
* urinary retention
111
what side effects do opioids have on the integumentary?
pruritis
112
which sensory receptors are responsible for fine touch?
* Meissner's corpuscle
* Merkel discs
* Root hair plexus
112
which sensory receptors are responsible for pressure?
* Ruffini's endings
* Pacinian corpuscles
* Krause's end bulbs
113
which sensory receptors are responsible for temperature and pain?
free nerve endings
114
compare the pain neurotransmitters
substance P is associated with acute pain; glutamate is associated with chronic pain
115
define bolus dose
a single, relatively large dose of medication administered rapidly to achieve a quick therapeutic effect
116
define lockout time
the minimum time that must pass between consecutive bolus doses delivered by a PCA pump
117
define dose duration
refers to the time over which a bolus dose is administered
118
define background infusion
a continuous, low-dose infusion of medication provided by the PCA pump, independent of patient-initiated bolus doses
119
what are the structures of the mesolimbic reward pathway?
Ventral tegmental area → nucleus accumbens → prefrontal cortex
120
