Pain Definitions/Basics

Question 1

Acute Pain: other physiological sx

Answer 1

tachycardia, htn, diaphoresis (sweating), mydriasis

Question 2

Chronic Pain: psych and nerves

Answer 2

social isolation, depression, anxiety

As pain signals are repetitively generated, neural pathways change and become hypersensitive

Question 3

Malignant Pain

Answer 3

acute, chronic, or intermittent d/t cancer or chemo

Question 4

Somatic Pain

Answer 4

skin, muscle, tendon, ligament, bone

sharp, stabbing, throbbing, aching

Question 5

Visceral Pain

Answer 5

internal organs like liver, intestines, or stomach

Poorly localize, often referred pain far from problem

Question 6

Neuropathic pain

Answer 6

Nerve damage - burning, numb, aching, electric shock

Question 7

Neuro pain first line

Answer 7

TCAs, antiepileptics, serotonin-NE reuptake inhibitors

Question 8

Nociception

Answer 8

Sensory nerve sends signal to spinal cord along ascending nerves. Secondary nerves in dorsal horn of spinal cord connects and relays to brain stem.

Question 9

Descending Antinociception

Answer 9

ntms from descending fibers inhibit pain transmission

opioids resemble these ntms

Question 10

Acute pain goal

Answer 10

Pain relief, short-acting meds

Question 11

Malignant pain goal

Answer 11

Relieve patient’s pain without inducing disabling AEs

LA usually more appropriate, short acting for b/t

Question 12

Chronic benign pain goal

Answer 12

Decrease intensity by at least 30%
Usually requires multimodal therapy-nerve blocks, rehab, PT, acupuncture, psychotherapy, meds
Non opioids and adjuvents involved

Question 13

Adjuvent

Answer 13

primary indication is not pain (TCAs, antiepileptics, anesthetics,

Question 14

Opioid MOA

Answer 14

Mimic endogenous opioid peptides in antinociceptive pathway - binding opioid receptors as AGONIST for analgesia. Opioid receptors are in CNS, pituitary, GI tract,
gray matter of brain, and dorsal horn of spinal cord.

Question 15

Mu receptor

Answer 15

Binding = analgesia, sedation, euphoria, respiratory depression, physical dependence, constipation, etc

Question 16

Delta receptor

Answer 16

Analgesia without many AEs (but no delta agonists exist)

Question 17

Kappa receptor

Answer 17

Analgesia, respiratory depression

Also anxiety, strange thoughts, nightmares, hallucinations

Question 18

Pure opioid agonist

Answer 18

Morphine (Methadone has NMDA too)

Primary activate mu, some kappa, most clinicaly useful

Question 19

Mixed agonist-antagonist

Answer 19

Agonist at kappa - weak analgesia
Weak antagonist at mu - dysphoria, pshychomimetic effects
Pentazocine is prototype
Buprenorphine is partial agonist at mu and kappa

Question 20

Opioid antagonists

Answer 20

block mu and kappa recptors, reverse respiratory and CNS effects
Naloxone, naltrexone

Question 21

Tolerance

Answer 21

larger dose same response
sometimes mistaken for dz progression in ca pt
NO TOLERANCE: constipation and neuroendocrine effects

Question 22

Physical dependence

Answer 22

withdrawal syndrome if stopped/quickly decreased

Question 23

Addiction

Answer 23

use for nonmedical reasons, despite harm, decreased control/compulsive use, craving