Neurophysiology: Pain Flashcards
what is pain
Pain is defined as a response to noxious stimuli which is damaging or potentially damaging to the normal tissues. Pain can be decribed in a lot of ways including:
-pricking
-stabbing
-ache
-shooting
-burning
-throbbing
what is the importance of pain sensation
- Pain gives warning signal about the existence of
a problem or threat. It also creates awareness of
injury. - Pain prevents further damage by causing reflex
withdrawal of the body from the source of injury - Pain forces the person to rest or to minimize the
activities thus enabling rapid healing of injured part - Pain urges the person to take required treatment to
prevent major damage.
what are the various ways of classifying pain
-based on the duration
-pathophysiological classification
-anatomical classification
-depending on components
what are the types of pain according to its components
Fast pain and Slow pain
what is fast pain
Fast pain is the1st sensation of pain when a stimulus is applied. It is a bright sharp, localized pain. it is followed by slow pain.
Fast pain is carried by Aδ fibres
what is slow pain
Slow pain is the pain that follows after fast pain. It is a dull, diffused, unpleasant pain.
It is carried by C fibers.
what are the classifications of pain under its duration
-Acute pain
-Chronic pain
dwhat is acute pain?
An acute pain is a sharp and intense (severe) pain that is localized and easily identified.
-It is usually localized before spreading to other areas
-It is caused by injury to muscle, bone, or other visceral organs
-The injury stimulates nociceptors
-The pain usually disappears after the source of the pain is treated, and the injury heals. It is usually treated with mediciations.
what is chronic pain
Chronic pain lasts for a longer period of time
-It is not easily described
-It is usually associated with a long term disease like osteoarthritis
-It is resistant to treatment by medication
what are the pathophysiological classifications of pain
-Nociceptive pain
-Neuropathic pain
What is nociceptive pain
This kind of pain results from activation of nociceptors, on injury to the tissues.
It has 2 types
-somatic pain
-visceral pain
wetin be somatic pain
This is pain resulting from stimulation of
-skin
-mucus membrane
-bone
-cartilage
-muscles
-ligament
-tendons
-joints
-connective tissue
what is visceral pain
This is due to stimulation of receptors in the visceral organs.
It is unpleasant and poorly localised.
The pain receptor in the visceral organs are stimulated by:
->substances like bradykinin and proteolytic enzymes released during ischemic reactions
->chemical substances like gastric juice that leak from ruptured ulcers into the peritoneal cavity
->spastic contraction of hollow organs (GIT esp.)
->Over distension of hollow organs
the pain receptors in visceral organs is stimulated by
The pain receptor in the visceral organs are stimulated by:
->substances like bradykinin and proteolytic enzymes released during ischemic reactions
->chemical substances like gastric juice that leak from ruptured ulcers into the peritoneal cavity
->spastic contraction of hollow organs (GIT esp.)
->Over distension of hollow organs
what is neuropathic pain
Neuropathic pain is due to the dysfunction, damage, compression or disease of a nervous structure.
It is either peripheral neuropathic pain or central neuropathic pain
what is peripheral neuropathic pain
This pain is caused by a damage or lesion of a peripheral nerve or dorsal root or dorsal root ganglion
what is central neuropathic pain
this occurs due to a lesion or disease of the structures of the spinal cord or brain
what is the anatomical classification of pain
the location on the body of affected tissue. Examples:
shoulder pain
neck pain
tooth ache
stomach ache
muscle cramps
neurological pain
myofascial pain
what is referred pain?
Referred pain is a pain perceived adjacent to or at a site away from the site of origin.
Deep pain of the visceral organs is referred to other areas, BUT superficial pain is not referred.
give examples of referred pain
- Cardiac pain is felt at inner part of left arm and left
shoulder - Pain in ovary is referred to umbilicus
- Pain from testis is felt in abdomen
- Pain in diaphragm is referred to shoulder
- Pain in gallbladder is referred to epigastric region
- Renal pain is referred to loin.