Pain Management Flashcards
1
Q
Define Algesia
A
Increased sensitivity to pain
2
Q
Define Alogenic
A
Pain producing
3
Q
Define Allodynia
A
A normally non-harmful stimulus is perceived as painful
4
Q
Define Analgesia
A
The absence of pain in the presence of a normally painful stimulus
5
Q
Define Dysethesia
A
An unpleasant painful abnormal sensation, whether evoked or spontaneous
6
Q
Define Hyperalgesia
A
A heightened response to a normally painful stimulus
7
Q
Define Neuralgia
A
Pain in the distribution of peripheral nerves
8
Q
Define Neuropathy
A
An abnormal disturbance in the function of nerves
9
Q
Define Paresthesia
A
An abnormal sensation, whether spontaneous or evoked
10
Q
What is acute pain?
A
- unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage
- <1 month
11
Q
What is chronic pain?
A
- Persistent pain associated with a distinct period of uninterrupted pain f 3 months or more, that includes negative sensory and emotional experiences
- > 3 months
12
Q
What is considered nociceptive pain?
A
Stimulus of specific nociceptors
- somatic
- visceral
13
Q
What is considered non-nociceptive pain?
A
- neuropathic
- inflammatory
14
Q
What occurs with somatic pain?
A
- identifiable focus
- tissue damage
- chemical release modulates pain
- Well localized area, sharp, hurts at area
15
Q
What occurs with visceral pain?
A
- diffuse, referred
- dull, cramping, squeezing
- Example: distention of organ capsule, obstruction of hollow viscous
- associated with autonomic reflexes such as N/V, diarrhea
16
Q
What occurs with neuropathic pain?
A
- Damage to peripheral or central neural structures resulting in abnormal processing of painful stimuli
- dysfunction of CNS
- Burning, tingling shock-like
17
Q
What occurs with inflammatory pain?
A
- sensitization of the nociceptive pathway from multiple mediators
18
Q
What is transduction?
A
The transformation of noxious stimulus (chemical, mechanical, thermal) into an action potential
19
Q
Explain the A-delta fibers
A
Fast, sharp pain
6-30m/sec
Reflex alert
20
Q
Explain the C-fibers
A
Slow
0.6-2m/sec
Dull, burning, throbbing, aching
21
Q
What are the chemicals released during transduction?
A
- substance P
- glutamate
- bradykinin
- histamine
- serotonin
- prostaglandins
- cytokines
- calcitonin gene
22
Q
What happens with the release of Substance P?
A
- C fibers (slow chronic pain)
- G protein linked neurokinin-1 receptor
- vasodilation, extravasation of plasma proteins, degranulation of mast cells, sensitization of stimulated sensory nerve
- *inflammation and algesia
23
Q
What happens with the release of Glutamate?
A
- CNS, A-delta and C fibers
- instantaneous effect, fast sharp pain
24
Q
What happens with the release of Bradykinin?
A
- peptic algesic
- Direct stimulating effect on peripheral nociceptors via bradykinin receptors
25
What happens with the release of Histamine?
- Amine released from mast cells, basophils and platelets—> via Substance P
* * edema and vasodilation
26
What happens with the release of Serotonin (5-hydroxytryptamine) [5-HT]?
- Amine stored and released from platelets after tissue injury
- Algesic
27
What happens with the release of Prostaglandins, thromboxanes and leukotrienes?
- made from COX-1 and COX-2
| - Hyperalgesia
28
What happens with the release of Cytokines?
- released in response to tissue injury
| * * increase production of prostaglandins—> HYPERalgesia
29
What happens with the release of Calcitonin gene-related peptide (CGRP)?
- peptide released from C fibers (afferent)
| - causes local cutaneous vasodilation, plasma extravasation and sensitization
30
What happens during transmission?
- Action potential is conducted from periphery to CNS
| - multiple pathways ( ex: spinothalmic (anterolateral) tract)
31
What happens during perception?
- occurs once signal is recognized by various areas of the brain
- amygdala, somatosensory areas of cortex, hypothalamus, anterior cingulate cortex
32
What happens during modulation?
- altering neural afferent activity along pathway:
Can either:
- suppress (inhibitory)
- enhance (excitatory)- mostly excitatory via substance P
33
What are the inhibitatory neurotransmitters and which receptors do they work on?
- Glycine —> Chloride linked (GlyR)
- GABA—> GABAa, GABAb, GABAc
- Enkaphalin—> mu, delta, kappa
- Serotonin—> 5-HT
- Norepinephrine—> alpha 2
34
What do NSAIDs do?
Treat mild to moderate post-op pain
- anti-infammatory, antipyretic, and analgesic properties
- inhibit COX —> thereby stop conversion of arachidonic acid to prostaglandin
35
What does Ketorolac (Toradol) do?
- Non-selective COX inhibitor
- 30mg IM equivalent to 12 mg morphine IM
- do NOT give longer than 5 days
36
What are contraindications for Toradol?
- coagulopathies
- renal failure
- active P.U.D./GIB
- history of asthma
- hypersensitivity to NSAIDS
- surgery with high potential for post-op bleeding
37
What does Acetaminophen do?
- decreases prostaglandin synthesis
- analgesic, anti-pyretic, and minimally anti-inflammatory
- contraindication—> liver failure
38
What do NMDA antagonists do?
Ketamine:
- prevents activation of NMDA receptor
- NMDA is associated with “wind up”
39
What do alpha 2 agonists do?
Clonidine and Precedex:
- interact with G protein coupled and 2 receptors, centrally and peripherally
- inhibit adenyl Cyclades and decrease cAMP
- activate post-synaptic K+ channels and inhibit presynaptice Ca+ channels which decrease neurotransmitter release
40
What do opioids do?
Bind to and activate G protein coupled receptors in periphery and CNS
- CNS: opioid receptors in dorsal horn, specifically REXED LAMINA II (substantiated gelatinosa), periaqueductal grey, medial thalamus, amygdala, lambic system
- Peripheral: afferent sensory fibers, GI tract, lungs, joints
41
What medications are used for acute pain in chronic pain patients?
- anti-convulsants
- anti-depressants
- corticosteroids
- methadone
42
What do anti-convulsants do?
Gabapentin (neurontin) and pregabalin (Lyrica):
- neuropathic pain syndromes
- inhibit neuronal excitation and stabilize nerve membranes
* should continue on the day of surgery
43
What do anti-depressants do?
- block re-uptake of serotonin and norepinephrine, thus increasing availability
* should continue
44
What do corticosteroids do?
- anti-inflammatory:
Decrease cytokines and prostaglandin release
* continue, possible stress dose
45
What does methadone do?
- synthetic opioid, NMDA, opioid receptor action
| - continue * does have opioid effect
46
When the source of pain cannot be identified we call it ________________.
Fibromyalgia
47
What are the 3 heuristic subdivisions of painful stimuli?
1. ) painful stimulation without tissue damage
- withdrawal from stimulation, stop damage
- local event
2. ) tissue damage without nerve damage
- pain persists after withdrawal, intensified response to tactile stimulation, sensation of pain will spread, release of response mediators
3. ) nerve damage
- direct damage to nerve
- can be demyelinating, or axonal
48
What are the 3 anatomic regions associated with pain?
- peripheral
- spinal
- cerebral
49
What are the goals in treating chronic pain?
- must address the source
- the dysfunctional inhibitory mechanism in the peripheral or spinal nervous system
- address the dysfunctional pain perception in the cerebrum
50
What are the 3 types of chronic pain?
- psychogenic
- inflammatory
- neuropathic
51
What is psychogenic chronic pain?
Term falling out of favor
| Unable to validate or find source
52
What is inflammatory pain?
- tissue damage resulting in pain and release of inflammatory mediators
- produce capillary vasodilation, smooth muscle contraction and promote synaptic transmission of pain implement to CNS (histamine, bradykinin, substance P)
53
T/F Substance P and substance P receptors are specifically associated with inflammatory pain and are diminished or absence in neuropathic and cancer pain
TRUE
54
What is neuropathic pain?
- nerves damaged, pain radiates along dermatome
- commonly leads to allodynia (painful stimuli that is normally not painful)
- differs from inflammatory pain—> persistent allydonia is not managed well with NSAIDS
55
What is wind up?
- cyclic response to pain that leads to abnormal pain response
- pts often labeled as drug seekers
