Pain mechanism 2 Flashcards
what is congenital analgesia?
the inability to feel pain due to a loss of function - inherited
what is erythromelalgia?
an inherited disorder where blood vessels in the lower extremities or hands are episodically blocked then become hyperaemic and inflamed.
what is peripheral sensitisation?
stimulus is amplified at periphery (sensory area)
what is central sensitisation?
stimulus is amplified at central (spinal cord-CNS)
what is primary hyperalgesia?
hyperalgesia at site of injury
what is hyperalgesia?
exaggerated response to a normally painful stimulus
what is secondary hyperalgesia?
hyperalgesia at uninjured areas
in inflammation and pain what happens during sensitisation?
- lowered afferent firing threshold
- increased response to fixed stimulus
- increased spontaneous activity
in what type of pain does the sensitisation process occur, acute or chronic?
chronic
what is neuropathic pain?
Pain initiated or caused by a primary lesion or dysfunction in the nervous system
what is allodynia?
pain from a stimulus that doesn’t normally evoke pain e.g. thermal and mechanical stimuli
what is dysaesthesia?
unpleasant abnormal sensation, (spontaneous or provoked)
what is hyperpathia?
abnormally painful reaction to a stimulus, especially a repetitive stimulus
what sites generate ectopic activity in chronic pain?
- sites of increased sodium currents
2. sites of decreased potassium currents
what effect does large amounts of sodium channels have at sites of ectopic impulses?
- may lower action potential threshold
- may cause spontaneous activity in damaged primary afferents
