Pharm Block II - Pain Management

Question 1

Gate control theory

Answer 1

Substantia gelatinosa (SG) are modulating pain gates between periphery and CNS. Brain interprets pain and sends motor response, pain gates are closed with other sensory nerves. Ex: Rubbing arm to reduce painful stimulus will close pain gates in lower back so no more painful nerve impulses are sent up, rather non-painful impulses sent up instead.

Question 2

Mu opioid receptors

Answer 2

High affinity for enkephalins and beta-endorphin, low affinity for dynorphins

Question 3

Kappa opioid receptor

Answer 3

Binds opioid peptide dynorphin as primary endogenous ligand; natural alkaloids and synthetic ligands bind the receptor

Question 4

Delta opioid receptors

Answer 4

Enkepalins as endogenous ligands. Activation results in some analgesia, less than Mu agonists.

Question 5

anesthesia

Answer 5

partial or complete loss of sensation, w/ or w/out loss of consciousness, as a result of disease, injury, or admin of anesthetic

Question 6

analgesia

Answer 6

absence of normal sense of pain

Question 7

hyperalgesia

Answer 7

an excessive sensitivity to pain ; painful stimuli are perceived as more painful

Question 8

hyperesthesia

Answer 8

an increased sensitivity to sensory stimuli, such as pain or touch

Question 9

allodynia

Answer 9

non painful stimuli are perceived as painful

Question 10

dysthesia

Answer 10

unpleasant sensations (ex: “pins/needles” or “ants crawling on skin”)

Question 11

hyperpathia

Answer 11

all stimuli (noxious & innocuous) are more intense

Question 12

Point of WHO analgesic ladder

Answer 12

Step-wise approach to determine the appropriate anagesic for patient

Question 13

Mild pain (1-4)

Answer 13

Start with step 1 drugs (acetaminophen, NSAIDs, aspirin), max dose should be tried before moving to step 2

Question 14

Moderate pain (5-6)

Answer 14

Start with step 2 drugs (codeine, hydrocodone, oxycodone, propoxyphene), typically prepared with non-opioids, if pain persists or worses move to step 3

Question 15

Severe pain (7-10)

Answer 15

Start with step 3 drugs (morphine - gold standard, hydromorphone, fentanyl, meperidine)

Question 16

Obtaining pain using ABCDE

Answer 16

Ask pt about pain regularly and assess it systematically; Believe pts and families in reports of pain and what relieves it; Choose pain control options approprate for pts, families, settings; Deliver interventions in timely, logical, and coordinated fashion; Empower pts and families and enable them to control their course.

Question 17

neuropathic pain

Answer 17

nerve pain, usually burning/tingling, or electric-shock like, a type of chronic pain from nerves in CNS getting damaged

Question 18

nociceptive pain

Answer 18

most often derived from stimulation of pain receptors. may arise from tissue inflamm, mechanical deformation, ongoing injury, or destruction. Can be visceral (poorly localized, originating from internal organ/cavity), or somatic (well-localized)

Question 19

idiopathic pain

Answer 19

pain that has no apparent underlying cause but is extremely real to the pt

Question 20

psychogenic pain

Answer 20

somatoform pain disorder is severe enough to disrupt everyday life. pain is like that of a physical disorder, but no physical cause is found

Question 21

Acute pain

Answer 21

Comes on quickly, usually severe, last relatively short period of time, caused by disease or trauma

Question 22

Tx for acute pain

Answer 22

Treat insult or remove injury/numb sensation. Block activation of afferent, alter receptor densities, increase endogenous opiates, modulate neurotransmitter activity.

Question 23

Chronic pain

Answer 23

Persists beyond normal tissue healing time (3 months)

Question 24

Tx for chronic pain

Answer 24

Methods aimed at symptom relief. Address issues beyond physical sensations: emotional, lifestyle, personality, anxiety, sleeplessness, depression.

Question 25

physical dependence

Answer 25

a state of adaptation that is manifested by a drug class specific withdrawal syndrome that can be produced by abrupt cessation, rapid dose reduction, decreasing blood level of drug, or administration of an antagonist

Question 26

tolerance

Answer 26

a state of adaptation in which exposure to a drug induces changes that result in a diminution of one or more of the drug’s effects over time

Question 27

addiction

Answer 27

a primary, chronic disease of brain reward, motivation, memory & related circuitry. Dysfunction in these circuits leads to characteristic biological, psychological, social, &spiritual manifestations

Question 28

Pros and cons of PRN dosing for pain management

Answer 28

By time patient feels pain, requests and receives pain med, pain has escalated, analgesic takes time to take effect, not well managed with PRN alone. Scheduled analgesics with PRN for breakthrough pain provide more consistent blood levels of analgesic, preventing peaks in pain - while PRN available for peaks in pain.

Question 29

Nonpharmacologic pain management

Answer 29

Cognitivie-Behavioral Therapy: focus on impact that though, behaviors, emotions have on pt’s pain (relaxation imagery). Physical agents: message, heat or cold applications. Trascutaneous Electrical Nerve Stimulation (TENS): noninvasive nerve stimulation to reduce acute/chronic pain.

Question 30

peripheral agents (acetominophen) MOA

Answer 30

inhibits prostaglandin synthesis in the CNS which makes it antipyretic and analgesic. No effect on inflamm or platelets

Question 31

NSAIDS MOA

Answer 31

propionic acid derivatives. irreversibly inhibit COX-1 and COX-2 & inhibit synthesis of prostaglandin precursors but not leukotrienes. Anti-inflamm, analgesic, anti-pyretic, alter platelet function, and prolong bleeding time)

Question 32

Opiods MOA

Answer 32

bind specific opiod receptors in CNS to produce effects that mimic the action of endogenous peptide neurotransmitters such as endorphins, enkephalins, and dynorphins

Question 33

Bisophonates (used for bone pain) MOA

Answer 33

analogs of pyrophosphate. decrease osteoclastic bone reabsorption

Question 34

neuropathic agens MOA for pain relief

Answer 34

all CNS acting drugs act by altering a step in the neurotransmission process either by affecting a presynaptic neuron from releasing neurotransmitters or by blocking a postsynaptic receptor.

Question 35

antidepressant agents MOA for pain relief

Answer 35

increases actions of norepinephrine and/or serotonin in the brain by blocking the neurotransmitter reuptake

Question 36

anticonvulsant agents MOA for pain relief

Answer 36

block voltage-gated Na+ or Ca+ channels, enhance inhibitory GABA-ergic impulses, interfere w/ excitatory glutamate transmission.these alter the pain threshold.