Pain Flashcards
What is nociception?
Physiological processing of tissue damaging information
Sensory aspect of pain (Somatosensory Component)
How is pain biologically advantageous?
Protective mechanism to prevent tissue injury and permit recovery from injury
What is the international association for the study of pain definition
An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage (it feels like —-)
Define hyperalgesia
Heightened pain (eg when damaged tissue is exposed to noxious stimulus)
What is allodynia?
Pain arising from gentle touch (painful response to a stimulus that would not normally be painful)
Key feature in chronic pain syndromes
Specific pain pathways allow the _____, _____ and _____ of pain
Specific pain pathways allow the localization, intensity and quality of pain
What is the affective component of pain?
- Production of negative emotion
- Arousal
- Initiation of stress responses
- Interruption of ongoing procedures (pain demands attention)
- Learning - plasticity in painful response
- Stress, anxiety, anticipation make pain worse (second response worse)
What is musculoskeletal and other ‘mild’ pain?
- initial response to tissue damage sensed by _________
- Transmitted by _________ ‘pricking’ pain (first pain)
- Secondary response; ongoing pain caused by release of _________ _________, _________ and _________ at site of lesion (second pain)
- Transmitted by _________ - burning, more diffuse pain - slow pain
- initial response to tissue damage sensed by ‘free nerve endings’
- Transmitted by sensory Adelta-fibres - ‘pricking’ pain (first pain)
- Secondary response; ongoing pain caused by release of bradykinin, histamine, acid metabolites and prostaglandins at site of lesion (second pain)
- Transmitted by C-fibres - burning, more diffuse pain - slow pain
What is Deep pain (Nociceptive pain)?
- Treated with ______
- deep aching pain, felt as deep to the body surface, poorly ______
- Initiated by ______
- Treated with opioids
- deep aching pain, felt as deep to the body surface, poorly localized
- Initiated by major trauma (post-operative pain, injury or childbirth)
- both deep pain and mild pain have been referred to as “good pain” - prevent overuse of damaged tissue and allow healing to occur
both deep pain and mild pain have been referred to as “good pain”, why?
prevent overuse of damaged tissue and allow healing to occur
What is neuropathic pain?
- Chronic pain resulting from ___\____
- Respond poorly to ___\____
- Treat with ___\____, ___\____ or ___\____ such as ___\____ or ___\____
- Chronic pain resulting from nerve injury or infections
- phantom limb pain
- trigeminal neuralgia
- diabetic neuropathy
- post herpetic neuralgia (shingles)
- HIV-AIDS neuropathy
- Respond poorly to opioids
- Treat with antidepressants, cannabinoids or anticonvulsants such as pregabalin or gabapentin
What are the most standard frontline treatments for neuropathic pain?
Pregabalin or gabapentin
Structurally similar to GABA
*Effect Ca++ channels
Why is chronic, neuropathic pain considered bad pain?
No obvious biological function
- injury should have already been recovered so the continued pain response is unecessary
Neuropathic pain:
- ______ onset
- most striking feature:
- Characterized by ______, _______, _______ and _______
Neuropathic pain:
- slow onset - outlasts original injury
- most striking feature: Stimulus independent pain
- Critical because there isn’t a noxious stimuli
- Characterized by allodynia, hyperalgesia, causalgia, and spontaneous (stimulus independent) pain
Pain Pathways:
- Afferent (sensory) neurons reside in ______ along spinal cord - send axons out to innervate body surface
- A-alpha, A-beta fibres:
- _______ ______ conducting
- Carry _______ information
- Convey_____. _____. _____
- Piezo 2 channels are _______
Pain Pathways:
- Afferent (sensory) neurons reside in dorsal root ganglia along spinal cord - axons innervate body surface
- Aalpha and Abeta fibres: non-pain fibres
- Myelinated rapidly conducting
- Large cell bodies and thick axons - heavily myelinated
- Carry innocuous information (non-pain)
- Convey touch, pressure, muscle afferent information
- Piezo 2 channels are mechanosensors