Measuring Pain Flashcards
What is the International Association for the Study of Pain 2019 definition of pain?
Pain = An unpleasant sensory and emotional experience associated with, or resembling that associated with, actual or potential tissue damage
True or false
We need potential tissue damage to feel pain
False
We don’t need potential tissue damage to feel pain
When thinking about pain what do you need to be aware of?
It’s an individual experience
It has a protective function
What is the pathway that lets you feel pain?
First in the pain pathway is a pain inducing stimulus
The pain receptors then activate and translate and transmit signals through C and A-Delta fibres
The signal travels through the C and A-Delta fibres to the Peripheral Central Nervous Systems spinal cord
This triggers a reflex to move the body part away from the pain inducing stimulus
The pain signal will then continue up to the brains thalamus to feel the pain
What is Molony 1997’s definition of animal pain?
Animal pain = “ An aversive sensory and emotional experience representing an awareness by the animal of damage or threat to the integrity of its tissues
It changes the animals physiology and behaviours to reduce or avoid damage, to reduce the likelihood of recurrence and to promote recovery”
What are the 4 types of pain?
1) Nociceptive
2) Neuropathic
3) Acute pain
4) Chronic pain
What is nociceptive pain?
Nociceptive pain is acute sharp pain
Nociceptive pain responds to the following stimuli:
- Thermal
- Mechanical
- Chemical
You can get superficial somatic vs deep somatic vs visceral
What is neuropathic pain?
Neuropathic pain is where damaged and/or sensitised nerves fire in the absence of tissue damage
What is acute pain?
Acute pain has relatively short duration of pain
It has an obvious cause
It resolves with healing
It has a protective function
What is chronic pain?
Chronic pain could have multiple causes
Chronic pain persists after healing
It’s often refractory to treatment
What are the consequences of pain?
First there’s inflammation, tissue injury and nerve damage which leads to pain
The following systems will then activate:
- Neuroendocrine systems changes
- Sympathoadrenal activation
- Neuroplasticity (spinal cord and CNS)
- Inflammatory mediators “sensitising soup”
- Central processing changes
Activation of all these systems leads to infection and impaired wound healing
What is neuroplasticity?
Neuroplasticity is changes in the somatosensory system which will generate central sensitisation and facilitated CNS transmission
The firing of these neurones then causes hyperalgesia and allodynia
True or false
Pain can lead to more pain if severe or prolonged
True
Sensitisation can have a persistent effect, which causes what?
Hyperalgesia
Allodynia
Define hyperalgesia
Hyperalgesia = “An increased response to a stimulus which is normally painful”
Define allodynia
Allodynia = Pain due to a stimulus which does not normally provoke pain
What types of indicators can be used to assess pain?
Physiological indicators Behavioural indicators Pain scales/questionnaire Threshold test and cognitive bias Neurological indicators
Give examples of physiological indicators of pain
Tachycardia, hypertension and cardiac arrhythmia
Pale mucous membrane
Mydriasis
Sweating, trembling, hypersalivation
Increased urination or defication
Poor body or coat condition
Changes in stress hormones such as:
Cortisol
Glucose
Insulin
Adrenaline
EndorphinsWhat are the 3 disadvantages of physiological indicators of pain?
They're unreliable and non-specific if taken as a sole parameter
We need knowledge about physiology of the species evaluated to know what's normal
Errors are increased with
Disease
Fear
Stress
Handling
Anaesthesia
EtcTrue or false
Behavioural indicators generally vary between species
True
True or false
It’s hard to distinguish behaviour between species so we need to know the normal behaviour of each species in order to see if the animal is presenting pain behaviour
True
True or false
Behavioural indicators don’t vary within species
False
Behavioural indicators vary within species
True or false
Due to the behaviour indicator variations we need to rely on people who know the animal well to pick up the subtle changes
True
Give examples of behavioural indicators used to measure pain
Abnormal posture Abnormal activity Abnormal movement Abnormal gait Reluctance to move Depression, inappetence, dullness Manic behaviour Not grooming Trembling Poor interaction with people, hiding Non-interested in surroundings Decreased interactions with other animals Tooth grinding Poor cognition Ear-flicks Aggression Paying attention to the injured area or wound, hyperalgesia when palpated Vocalisation Whining, crying, howling Head hanging down, low tail carriage
