Whether it’s the chronic pain of illness and age or the acute pain of accident and intervention, it’s generally accepted that animals experience not just pain, but emotional distress. But how to recognise and evaluate pain in animals? The Glasgow Composite Pain Scale (GCPS) provides an objective assessment.
Assessment of an animal’s pain
For the veterinary professional, there’s a whole range of measurable indicators on which to base an assessment of an animal’s pain. Changes in an animal’s blood pressure and heart rate may be interpreted as indications of stress or a response to physical trauma related to the experience of pain.
With the resources of a veterinary laboratory, hormonal, metabolic, gastrointestinal and homeostatic changes – such as blood clotting times, provide further validation or contradiction of opinions formed in the veterinary surgery.
Evidence-based veterinary response
These ‘professional’ assessments of an animal’s pain status depend on physiological information not available to an animal’s owner or keeper. For the animal’s closest companion, the best available indicators of pain are changes in their animal’s normal patterns of behaviour, development and expression. For the veterinary clinician, behavioural signs – together with the observations of owners and keepers, contribute to a complete, evidence-based veterinary response.
Non-physiological indicators of pain might include changes in activity, the development of new activities – such as limping, vocalisation, body language, excessive scratching or licking, and even facial expressions. For example, a relaxed and comfortable cat will normally sit feet curled under the body, head up, ears up and eyes wide open. While cats suffering discomfort will often lie flat and with half-closed or squinting eyes.
Owners need to develop a high degree of familiarity with their pet
Neurological studies on rodents support the ‘pained face’ as a reliable indicator of pain, showing that there is an emotional factor in an animal’s response. Picking up these non-verbal signals requires owners to develop a high degree of familiarity with their pet’s ‘normal’ behavioural state. It also requires a consistent, validated scale of measurement.
The Glasgow Composite Pain Scale (GCPS) provides an objective assessment of pain and allows subsequent assessments to help determine if an animal’s pain is getting better or worse. Devised by Glasgow vet school, the scale helps to improve veterinary diagnosis of acute, postoperative pain and the appropriate treatment of long-term, chronic pain.
The Glasgow Scale questions behaviours including vocalisation, attention to wound, mobility, sensitivity to touch, demeanour and activity. Responses are scored as to which best describes the animal’s behaviour and scores totalled to give a maximum pain score from 0 to 24.
Animals might not be able to communicate verbally, but with the GCPS objective scale of measurement, vets can encourage owners and keepers to speak up on their behalf.