Week 8: Pain-emotion, sensation, or vital sign? Flashcards
Define pain.
An unpleasant sensory and emotional experience associated with actual or potential tissue damage.
What are the main factors that influence nociceptive (processing of noxious stimuli) inputs affecting pain perception?
- Chemical and structural: opioidergic/dopaminergic dysfunction, atrophy
- injury: peripheral and central sensitization
- Genetics
- context: beliefs, expectations, placebo
- Cognition
- Mood
What is the pathophysiology of pain?
Trauma–>cell damage–>arachidonic acid–>prostaglandins–>
a. inflammatory prostaglandins
- sensitizes pain receptors
b. cytoprotective prostaglandins
- protects gastric mucosa
Compare and contrast acute pain (nociceptive/inflammatory) and chronic pain (neuropathic).
ACUTE
-protective response of body to trauma or inflammation
-pain relieved when inflammation resolved
-respond to non steroidal anti inflammatory agents
CHRONIC/NEUROPATHIC
-no protective purpose or biological value
-persists beyond healing period
-doesn’t respond to NSAIDS
Describe the generalized approach to treatment of acute pain in the ED.
pain assessment–>acetaminophen–>NSAIDS–>Opioids (Oral for moderate pain or IV for severe pain)–>sedation/anesthesia (procedural sedation for brief procedural pain or sedation anesthesia for intractable pain)
Define neuropathic pain.
Initiated or caused by a primary lesion or disease in the nervous system.
Divided into central and peripheral
-most common peripheral: diabetes and Herpes
-most common type of pain: lower back pain
How is neuropathic pain diagnosed?
- History
- spontaneous pain: burning, shooting, or electric pain
- paresthesia (tingling)
- dyesthesia (pins and needles)
- pain worse at night and unable to tolerate even bed sheet on skin - Sensory exam: light touch and pin prick
- allodynia: pain from skin touching cotton swab
- hyperalgesia-exagerrated response to painful stimuli
- hyperpathia-summation of pain after repetitive stimulus - skin exam: color, temp, swelling, hair loss, sweating (sympathetic pain)
- musculoskeletal and myofascial exam: joint, fascia, tendon
- many issues secondary due to lack of movement due to pain - basic psychological exam
- lab tests: nerve conduction studies
- skin biopsy
- neuroimaging: usually only for CNS pain
Describe the treatment approach to neuropathic pain.
clinical–>Diagnosis NP–>disability assessment (functional, psycho, sleep)–>patient education–>individualize management (degree of disability, patient participation-preference, prior response, co existing conditions)
Describe approach for pharmacologic treatment of neuropathic pain.
- medication trial of 6-8 weeks
- start low doses
- duration: at least 6 months
- goal of treatment: patient driven
What are some FDA approved medications used for neuropathic pain?
- tricyclic antidepressants
- sodium channel blockers, potentiate analgesic action of adrenergic system, also treats insomnia - antiepileptics
- anti arrythmic
- topical/dermal
- sympatholytic agents: clonidine
- opiates, tramadol
- opioids increase NMDA hyper excitability, which leads to tolerance and can increase long term pain/hyperalgesia - others: steroids
What are physical and psychological treatments for neuropathic pain?
- physical therapy
- behavioral: relaxation, hypnotherapy, cognitive/beahavioral management therapy
- patient education, family counseling, sleep hygein
- invasive techniques: local anesthetic blocks, epidural administration, spinal cord stimulation, intraspinal/intrathecal medications
What are the goals of pain management programs?
- improve patients understanding of their situation
- improve level of physical functioning
- promote self management
- modify their perceived level of pain and suffering
