Pain Theory Flashcards
Pain
Unpleasant sensory or emotional experiences that is associated with actual or potential tissue damage
Tolerance
A physiological adaptation to a drug that causes a muted drug effect
Opioid-induced hyperalgesia
Pain as a result of exposure to opioids
Hallmark sign
State where there are withdrawal symptoms if drug is not given
Neuromatrix theory of pain
Addresses the influence of sensory, affective, and cognitive aspects of pain
Addresses pain transmission and modulation in certain areas of the brain
Biopsychosocial approach to pain
Views pain as a complex experience affected by sensory input, but also closely influenced by behavioral, cognitive, affective, and environmental factors
Gate Control Theory of Pain
Pain stimuli is either allowed to pass or is blocked by a gate in the dorsal horn of the spinal cord
Anxiety, negative thoughts, poor past experience, or depression can open the gate and increase perception of pain
Positive thoughts and relaxation can close the gate to decrease perceptions of pain
Opioid Mediated Theory of Pain
Theory that endogenous opioids are pain-mediating chemicals that are produced in the body and affect the CNS and PNS
Nociceptors
Receptors that detect and respond to potential or actual tissue damage
Sensitive and responsive to mechanical distorition and variation in chemical components in tissues
Anxiety, stress, or depression may amplify pain perception
A-delta fibers
Myelinated pain fibers that carry sharp, well-localized pain signals
C-fibers
Unmyelinated pain fibers that carry poorly localized burning and aching sensations and are easily injured
Pain pathway
- Afferent fibers
- T-cells receive input from afferent fibers and assist in discriminating the type of pain
- Brain
- Descending inhibitory fibers in higher brain center release neurotransmitters to affect flow of afferent impulses
Somatosensory cortex for pain
Perceives pain as sharp, discriminative, and localized to a specific area
Is responsibile for automatic reactions to pain
Spinoreticulothalamic pathway
Terminates in the thalamus/midbrain region
Perceives pain as diffuse, poorly localized somatic and visceral pain
Frontal cortex in pain
Defines perceptions and response to pain
Signals to release neurotransmitters which moderate and affect flow of afferent impulses
Acute pain
Lasts seconds to days and warns of potential tissue damage
Initiates inflammatory response causing redness, swelling, increased local temperature, and pain
Substance P sends electrical impulses through afferent fibers of spinal cord in response to injury
Acute recurrent pain
Episodes of pain with pain-free periods between flare-ups lasting less than 3 months
Chronic pain
Pain that persists beyond the stage of healing and lasts longer than 3-6 months
Typically poorly localized with underlying cause not being fully understood
Referred pain
Pain that is perceived at a location unrelated to the site of trauma that projects outward and distally
Trigger point
Hypersensitive points in the muscle that cause referred pain
Radiating pain
Originates from an irritated nerve root
Pain travels along the nerve’s dermatome
5 types of neurogenic/neuropathic pain
Peripheral neuropathic pain
Peripheral nociceptive pain
CNS mediated pain
ANS mediation of pain
Affective motivational component
Peripheral neuropathic pain
Caused by involvement of neural tissues resulting in mechanical and physiological changes in the body including limitations in movement, pain, paresthesia, or sensory changes
Impact of chronic pain on health and function
Negative impact on occupational performance and success
Increased heart rate, sweating, muscle guarding, breathing rate, and blood pressure
fear of pain or reinjury causes limitations in activity and movement
