Pain and Healing Flashcards
what is pain?
a warning of actual or potential tissue damage
an essential function for survival
a complex interaction between mechanical neurological, psychological, and sociological factors
what are nociceptors?
receptor of a sensory neuron that responds to potentially damaging stimuli
it sends signals to the spinal cord and brain
Peripheral sensitization
Is a lowering of the nociceptor firing threshold in response to the release of various substances for nociceptive afferent fibers
It causes an increased magnitude of response to stimuli and an increase in the area from which stimuli can evolve action potentials
central sensitization
process of central nervous system adaptation to nociceptive input that changes transmission from peripheral nerves to the CNS; increase in the magnitude and duration of the response to noxious stimuli (primary hyperalgesia); enlarges the receptor fields of the nerves (secondary hyperalgesia); normal non-noxious stimuli becoming painful (allodynia)
What is released during the fight or flight response?
Release of epinephrine, norepinephrine, endorphins and other hormones and neurotransmitters
What does the fight or flight response result in?
Increased attention, muscle tone, hearth rate, BP, and skin conductance
How are pain receptor activated?
by intense thermal, mechanical, or chemical stimuli (both internal and external)
What is the role of pain receptors?
to convert stimulus into electrical activity to form action potentials; the signal travel along afferent nerves toward the spinal cord and the brain
what are the 3 kinds of peripheral pathways
A-delta fibers (small and myelinated), C fibers (small and unmyelinated), A-beta fibers
What are A-delta fibers?
small and myelinated peripheral pathways that are the thickest and fastest fibers; respond to intense mechanical stimuli and heat or cold; are sensations that are sharp, stabbing, or prickling
what are C fibers?
small and unmyelinated peripheral pathways that are slow in onset, long lasting, diffusely localized, accompanied by sweating, increased heart rate and BP or nausea; the sensations are dull, throbbing, aching, burning, tingling, or tapping
what are a-beta pathways?
they are peripheral pathways the are non-painful sensations related to vibrations stretching, and mechanical pressure; they can be involved in abnormal, prolonged pain perception
sympathetic nervous system influences on pain modulation and control:
fight or flight response
chronic sympathetic activations frequently exacerbate pain
motor system influences on pain modulation and control:
muscles can become stiff in order to protect tissue from further pain or injury; pain can thus lead to impairment of movement and balance
What is acute pain?
The direct result of actual or potential tissue injury due to a wound, disease, or invasive procedure; expected to resolve w/in 3-6 month depending on pathology
What is chronic pain?
pain that is enduring or recurrent and persists longer than typical for a condition; there is an inadequate response to appropriate and/or invasive care; it can cause a significant impairment or functional status