Pain Flashcards
What’s pain
Unpleasant sensation due to damage
Things associated with pain
Somatic reaction
Autonomic reaction
Emotional reaction
Other signs of damage other than pain
Fever
High ESR
Significance of pain
Warning
Reaction
Pain receptors ?
Free nerve endings
Functional classification of pain receptors
Mechanical
Chemical
Thermal
Poly modal
Pain receptors are abundant in :
Skin Periosteum Vascular walls Joints Dura of falx and tentorium
Pain receptors are less abundant in :
Most viscera
Many deep tissue (Muscles, Ligaments, Tendon)
Pain-insensitive tissues
Brain
Liver parenchyma
Kidney parenchyma
Lung parenchyma
Classes of pain producing compounds
1st class 2nd class
Which class of PPS directly stimulate pain receptors
1st class
Which class of PPS lowers pain threshold
2nd class
Substances of the 1st class of PPS
Potassium
Histamine
Serotonin
Bradykinin
Substances of the 2nd class of PPS
Substance P
PGE 2
Leukotriens
Qualities of pain
Pricking Burning Colicky Dull Throbbing Tearing Oppressive Stabbing Stitching
Classification of chronic non malignant pain
Generalized
Neuropathic
Nociceptive
Ex. of generalized pain
Fibromyalgia
Ex. neuropathic pain
HIV
Amputation
Nerve injury
Ex. nociceptive pain
Osteoarthritis
Migraine
Characters of neuropathic pain
Tingling Numbness Burning Shooting Paroxysms Hyperalgasia Sympathatic dystrophy Hard treatment Partial res. To opioid May respond to TCA
Sources of pain
Cutaneous
Deep
Visceral
Types of cutaneous pain
Fast
Slow
Afferent of types of cutaneous pain
Fast > A-delta
Slow > C
Pathway of types of cutaneous pain
Fast > Neospinothalamic
Slow > Paleospinothalamic
Neurotransmitter of types of cutaneous pain
Fast > Glutamate
Slow > Substance P
Reactions to pain
Somatic motor reaction
Autonomic reaction
Emotional and psychological reaction
Somatic motor reactions to pain
Withdrawal
Increase muscle excitability
Spasm of nearby muscles
Autonomic reactions to pain
Mild pain > Sympathatic
Severe pain > Parasympathetic
Emotional and psychological reactions to pain
Anxiety Fear Crying Depression Hurt
Chronic pain does not mask ………….
Depression
What’s hyperalgesia
Skin become more sensitive to pain after 30-60 minutes of injury
Types of hyperalgesia
Primary
Secondary
Mechanism of primary hyperalgesia
Decrease pain threshold
Mechanism of secondary hyperalgesia
Convergence-facilitation theory
Characters of deep pain
Poor localization Dull C-Fibers Somatic reaction Autonomic reaction Hyperalgesia
Visceral pain types
True visceral pain
Parietal visceral pain
Afferent fibers of types of visceral pain
True > C fibers
Parietal > A-Delta and C fibers
Appendicitis pain
Start > Around umbilicus
Later > Right iliac fossa
Cardiac pain
Retrosternal
Left side of neck
Inner side of left arm, forearm and little finger
Gall bladder pain
Epigastric region
Right shoulder
Neck
Mechanism of referred pain
Convergence projection theory
Components of pain control system
PeriAqueductal grey area
Raphe magnus
Nucleus reticularis paragigantocellularis
Locus ceruleus
