Page 180 - BSAVA Guide to Pain Management in Small Animal Practice

7 | Pain in birds

VetBooks.ir vague, inconsistent signs behaviours and Evaluation of analgesics
often simply uses clinical udgement and
etermining the likely e cacy of a chosen
experience to choose the type, level and
duration of analgesia to provide. Pain scales analgesic can be problematic in birds. o do
and score sheets can improve the provision of this e ectively it is important to know the
analgesia as pain occurs on a gradient rather pharmacokinetic P and pharmacodynamic
than all or nothing , but these are still in the P properties of the drugs in the target
development stage for avian medicine due to species. Extrapolation across species with
the di culty in observing and appreciating respect to dose and dose fre uency has been
signs of pain. Simple 1 1 scales and more shown to be unreliable. owever, due to the
detailed numerical scales have been trialled relatively small number of P and P studies
and show signi cant correlation awkins and in birds, the clinician often has no choice but to
Paul urphy, 11 . E ective analgesia is do this, or rely on anecdotal reports, to select
expected to result in discernable changes in analgesia for their avian patients. oses from
posture or behaviours that will translate to a the literature, along with the recommended
change in the pain score. If no change in pain doses from this author, can be found in
score occurs, drugs, dose, or fre uency of igure 7. 1.
administration need re evaluation for that he Veterinary edicines irectorate
individual. In clinical practice, where pain Cascade must also be considered, as
scoring may not be commonplace, simply analgesics are invariably used o licence due
administering analgesia where appropriate and to lack of licensed products for birds.
seeing if it helps is a good and reasonable way Opioids
to determine if pain is present. here there is
doubt, it is advisable to assume pain is present pioids vary in their receptor speci city and
and to treat it, rather than risk leaving the bird e cacy in mammals, resulting in a wide variety
without analgesia and su ering the negative of clinical e ects. In birds, there is a lack of
e ects of pain. published data on opioid receptor distribution,
Painful conditions in birds can be loosely density and functionality. ansour et al. 1988
grouped into the following areas showed that in pigeons, kappa and delta
receptors were more prominent in the forebrain
■ rthopaedic trauma fractures, luxations and midbrain than mu receptors and 76 of
and sprains opioid receptors were kappa type. here is still
■ Soft tissue in ury cuts, deep bruises, blunt much to be learned some birds fail to respond
trauma well to mu agonists and others respond
■ Visceral pain pancreatitis, bowel similarly to mammals to both mu and kappa
obstruction or distension, kidney in ury, agonists. It has been postulated that birds may
tumour related not possess distinct mu and kappa receptors
■ steoarthritic pain age related, or that they have similar function Concannon
degenerative oint disease, in ammatory or et al., 199 .
immune mediated .

drugs
Common clinical presentations where pain
relief is indicated include any form of trauma, It is generally assumed that the chemistry and
age related degenerative oint disease, soft mechanism of action is similar in birds and
tissue in uries such as broken nails and skin mammals athonnet et al., 1 . here is little
wounds, and abdominal distension caused scienti c support for a washout period Papich,
by coelomitis or some other form of space 8 and this could put the bird at risk of
occupying disease such as an obstruction having untreated pain, although multiple
or tumour. non steroidal anti in ammatory drugs NSAI s

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