Pain/Fever Lecture

Question 1

What is somatic pain?

Answer 1

Skin, bone, joint, muscle, connective tissue

Question 2

What is visceral pain?

Answer 2

Internal organs–> pancrease, large intestine

Question 3

Define nociceptive pain

Answer 3

acute pain

Question 4

Define neuropathic pain

Answer 4

chronic pain

Question 5

What is the gate control theory of pain?

Answer 5

Brain acts as a gate to increase/decrease flow of nerve impulses from peripheral fibers to CNS

Question 6

What is the neuromatrix theory?

Answer 6

Each person has a unique genetically built in network of neurons called self body neuromatrix

Question 7

What happens when there is stimulation of nociceptors?

Answer 7

Releases: luekotriens, serotonin, histamine, PGs, substance P, bradikinins
Receptor activation is transmitted along afferent nerve fibers to the spinal chord

Question 8

What are nociceptors?

Answer 8

Found in somatic and viceral structures
Activated & sensitized by mechanical, thermal and chemical impulses
Distinguish between noxious and inncuous stimuli

Question 9

How is nociceptive pain transmitted?

Answer 9

Large diameter and sparsely myelinated A fibers evoke sharp and well localized pain
Small diameter unmyelinated C fibers produce dull aching and poorly localized pain

Question 10

What do afferenct nociceptive pain fibers release?

Answer 10

Neurotransmitters: glutamate, substance P and calcitonin gene-related peptide

Question 11

What does the thalamus do?

Answer 11

Works as a relay station for transmission

Question 12

What is pain influenced by?

Answer 12

Interactions between neuroreceptors and neurotransmittors in the synapse

Question 13

What is pain perception?

Answer 13

Conscious experience takes place in higher cortical region in the brain
Brain can only accommodate limited number of pain signals
Cognitive and behavioral functions can modify pain by decrease pain signals
Relaxation, distraction, mediation, help in reduction

Question 14

What is modulation of pain?

Answer 14

Endogenous opiate system
Neurotransmitters: endorphins, dynorphins, enkephalins
Recepts: mu, delta, kappa
Endogenous opioids bind to receptors- modulate pain impulse

Question 15

NMDA activation leads to?

Answer 15

Decrease binding of opiates to receptors

Question 16

What occurs in chronicn pain?

Answer 16

Disengaged from noxious stimuli
Nerve damage
Burning, tingling, shooting pain

Question 17

What is the location, nature, onset and duration of tension-type headaches?

Answer 17

Bilateral
Varies from diffuse ache to tight pressing constricting pain
Gradual
Minutes to days

Question 18

What is the location, nature, onset and duration of migraine headache?

Answer 18

Usually unilateral
Throbbing
Sudden
Hours to 2 days

Question 19

What is the location, nature, onset and duration of sinus headache?

Answer 19

Face, forehead, or periorbital area
Pressure behind eyes or face
> Dull, bilateral pain & worse in the morning
Simultaneous with sinus symptoms
Days

Question 20

What is the vascular hypothesis of migraine headaches?

Answer 20

Intracerebral aterial vasoconstriction followed by extracranial vasodilation

Question 21

What happens during a migraine headache?

Answer 21

Perivascular axons release calcitonin gene-related peptide, neurokinin A and substance P
Released peptides interact with dural blood vessels to promote vasodilation and neurogenic inflammation

Question 22

Migraine headache’s neurotransmitter is what?

Answer 22

Serotonin (5-HT)

Question 23

What is Devil’s Claw?

Answer 23

Inhibits lipoxygenase and COX-2
Helps in the production of TNF-alpha (anti-inflammatory)
- Lower back pain
50-100 mg harpagoside daily reduce low back pain
Cause hypoglycemic effects

Question 24

What is feverfew?

Answer 24

Leaves used for prevention of migraine headaches
- Reduce incidence of attacks
Less nausea and vomiting
Inhibits PG synthesis
Increases risk of photsensitivity

Question 25

What is comfrey?

Answer 25

Suppress degranulation of azurophil granules and superoxide generation in leucocytes Reduces inflammation Same effect as diclofenac in reducing pain and inflammation Contains pyrrolizidine

Question 26

What is bromelain?

Answer 26

May inhibit the synthesis of PGs Activates plasmin produciton from plasminogen Reduces pain and inflammation after tooth extraction May reduce pain while walking after episiotomy Increase absorption of antibiotics Inhibit platelet aggregation-risk of bleeding Lowers bradykinin and kininogen

Question 27

What is a fever?

Answer 27

``` Rise in body temperature Normal = 37 Fever - 37.8 Thermoregulation in response to pyrogens Deregulation results in fever Infections frequently cause this ```

Question 28

Define Hyperpyrexia

Answer 28

Temperature over 41.1 or 107

Question 29

What is the pathophysiology of fevers?

Answer 29

Microbial infection Noninfectious: cancer, tissue damage, surgery, etc Drug induced: anti-infective, anti-neoplastics, cardiovascular, CNS agents Pyrogens: Exogenous (microbes, toxins) or endogenous (TNF)

Question 30

What are anti-infectives?

Answer 30

Isoniazid, sulfonamids

Question 31

What are anti-neoplastics?

Answer 31

Chlorambucil | Daunorubicin

Question 32

What are cardivascular?

Answer 32

Nifedipine | Procainamide

Question 33

What are CNS agents?

Answer 33

Barbiturates | Lithium

Question 34

How is the hypothalamus involved in fever pathophysiology?

Answer 34

Controls body temperature homeostasis by setting a target temp for the Feedback: peripheral nerves sending cool/warm sensation to brain and tissue Balances heat loss and production

Question 35

How could you increase the set temp?

Answer 35

Exposure to pyrogens results in release of arachidonic acid metabolites These metabolites cross BBB, and increase the temp

Question 36

What do sympathetic signals cause?

Answer 36

Vasoconstriction and decreased heat loss through skin

Question 37

What drugs are used for pain/fever management

Answer 37

Acetaminophen (inhibit COX3) Aspirin (inhibits cyclooxygenase --> decreases PGs; inhibit COX1) Ibuprofen (inhibits cyclooxygenase --> decreases PGs; inhibit COX1) Other NSAIDs