Midterm - Pain Flashcards
2 groups of analgesics
opioids (narcotic analgesics)
non-steroidal anti-inflammatory drugs
range of analgesic use
84% (orthopaedic surgery) - 17% (castration)
top 2 reasons provided for a lack of analgesics
- difficulty recognizing pain
- lack of knowledge about appropriate theory
2 components that pain consists of
- nociception, physical hurt or discomfort caused by injury or disease
- perception/emotional suffering
nociception
a detection and reflex response to damage to distinguish it from feeling pain
what does pain do to an animal
changes the animals physiology and behaviour
purpose of pain in animals
to reduce/avoid damage
reduce likelihood of recurrence
promot recovery
theory of analogy
while all beings do not experience identical feelings, we can use the strength of the similarities to justify inferences about an individuals subjective state
release of chemicals when tissue is damaged
chemicals stimulate free nerve endings that project to the spinal cord via a cell body in the dorsal root
in bones, joints, tendons and ligaments, where is the pain originating
pain originates from the cortex, marrow or periosteum of a bone
what are more sensitive, joints or bones
joints
what do joint nociceptors respond to primarily
pressure - the blood in a joint activates pressure receptors and initiates inflammatory response
degenerative osteoarthritis
typical in older animals - dairy cows, bulls and dogs
osteochondritis dessicans
erosion of the cartilage in a joint and the underlying bone, loose cartilage may occupy synovial space
what is the single greatest cause of pain in vertebrate species
inflammatory pain - does not necessarily need to have an external trigger
dolor
pain
calor
heat
rubor
redness
tumor
swelling
function laesa
loss of canton
why does ischaemic pain occur
due to a lack of blood flow from pressure on an artery
feeling created by electric shock
- direct activation of nerves near contact point - travels to brain
- muscle contraction
3 approaches to control pain following surgery
- allow animal to recovery from anaesthesia
- in anticipation of pain on recovery, an analgesic is given before surgery is started
- in anticipation of pain on recovery, an analgesic is given after completion of surgery but before recovery
what are the stressors when recognizing animal pain
pain and nociceptive stimuli
what is physiological pain confounded by
physiological and behavioural stress response to tissue damage and handling stress
cardiovascular response to pain
elevation in heart rate
respiratory response to pain
elevations in respiratory rate
endocrine response to pain
various changes in stress hormones
3 main classes of behavioural changes for pain assessment
- pain specific behaviours
- declines in the frequency or magnitude of certain behaviours
- choice or preference tests
required qualifications to recognize and assess pain
- good knowledge of species-specific behaviour
- knowledge and comparison of individual animal’s behaviours before and after pain onset
- use of palpitation and manipulation of the affected area and assessment of the responses
- examination of the level of function of affected area
- use of analgesics or dose rates that have been shown to be effective
- knowledge of non-specific effects of an analgesic, anaesthetic or other drugs that have been administered
good way to measure pain
facial expression - noxious stimuli of moderate duration
limiting factors for pain management in farm animals
- limited methods of pain assessment
- availability of analgesics
- different countries
- animal type
- lack of clinical trials
- if animals product is for market use
- economic considerations
reasoning for castration
reduce aggression
improve handler safety
reduce sexual behaviour
avoid unwanted pregnancy
improve meat quality
