Lecture 25: Clinical Pain Physiology, Assessment and Treatment I Flashcards
what is pain
Unpleasant sensory and emotional experience (perception) associated with actual or potential tissue damage
What are some reasons why adequate analgesia may not be provided
- Economic and practical
- Attitude towards pain in animals
- Tradition
- Failure to recognize adverse effects of pain
- Removing protective effects of pain
- Tx pain may interfere with dx
- Lack of information
- Failure to recognize pain
What are some reasons to treat pain
- Quicker recovery
- Shorter hospital stays
- Fewer re-admissions
- Improved QOL
How does pain affect immune system
Increase cortical levels which impair wound healing and cause immunosuppression
How does pain affect respiratory system
- Decrease pulmonary function
- Increase incidence of pneumonia
What are affects of pain on GI system
Shunting of blood, decrease GI motility, decrease mucosal integrity
What affects does pain have on cardiovascular system
- Activate RAAS- hypertension
- Decreased renal perfusion
- Increase HR, SV, CO and myocardial O2 consumption
What is a nociceptor
Receptor preferentially sensitive to a noxious stimuli
What is nociception
Perception of noxious stimuli
What are the 5 processes of nociception/ pain pathway
- Transduction
- Transmission
- Modulation
- Projection
- Perception
What is transduction
Noxious stimuli sensed and transduced into electrical signals by nociceptors
Where are nociceptors located
Primary afferent neuron
What are the 2 nociceptor nerve endings
- A-delta
- C-fibers
What physiological effects occur at site of transduction
Vasodilation, edema, and inflammation
Transduction results in ___of primary order nociceptors
Sensitization
__are called sleeping receptors activated by tissue damaging events
A-delta and C-fibers
A-delta and C-fibers play an important role in peripheral n___
Sensitization
What is transmission
Propagation of action potential by the afferent neurons to the spinal cord
Describe the functions and characteristics associated with A-delta fibers
- Myelinated
- Fast condition to acute pain
- Sharp and well localized pain
- Chemical and mechanical information
Describe the functions and characteristics of C- fibers
- Unmyelinated
- Slow conduction
- Poorly localized dull pain
- Burning sensation
- Chronic pain
Describe the function and characteristics of A-beta fibers
- Myelinated
- Very fast
- Non-noxious stimuli
- Pressure and proprioception
What is modulation
Information is augmented or inhibited at the level of the spinal cord