SAEVA Congress 2018 Proceedings | 12-15 February 2018 | ATKV Goudini Spa
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Conjunctival mass removal
Corneal biopsy, superficial keratectomy
Diamond burr keratotomies [Algerbrush]
Intrastromal corneal injections [e.g. Voriconazole]
Cytology sample
Corneal laceration repair
Aqueous paracentesis
Intracameral injection [e.g. tPA]
Intravitreal injection
Suprachoroidal injection e.g. triamcinolone
Enucleation
Exenteration
Subconjunctival Cyclosporine implants [not suprachoroidal implants]
When one is considering performing a standing ophthalmic surgical procedure not
every patient may be suitable. Patient selection is the first step for a successful
standing procedure. Fractious or highly stressed horses are unlikely to tolerate any
manual restraining and handling and highly sympathetically driven animals may also
appear to be resistant to standard doses of sedatives. However, unpredictable
oversedation may result with the use of higher dosages. The entire team involved in
the procedure needs to be adequately prepared regarding the location of where this
is to be performed. Choose a quiet location where the horse can be well restrained in
a safe manner [in a crush] both for the patient as well as the attending personnel. It
is essential the team is aware of the procedure to be followed and management of
any emergency in case an emergency arises or the horse falls in the crush. All
equipment and emergency medications should be prepared in advance to ensure
appropriate intervention under these conditions. The major risk of standing sedation
is the possibility of the patient falling to the ground. It is wise to place cotton wool
earplugs or even a mask over the contralateral eye to prevent the horse tracking
activity in the room with the contralateral globe. Ideally there should be no bright
lights, noise and other horses in the vicinity. Try and avoid full boarded crashes as
this makes it difficult getting to the horse in an emergency. As part of the patient’s
preparation, an intravenous catheter should be placed for drugs and fluid
administration, and the horse’s mouth should be washed in case there is a need for
endotracheal intubation. A recommended intervention in such cases may be a rapid
induction of general anaesthesia and placement of the patient in an appropriately
padded stall for recovery. One should always calculate and have available
appropriate doses of induction agents (i.e., ketamine and diazepam and even
euthanaze). Always plan for the worst scenario.
There is no doubt that there are also disadvantages to performing standing
ophthalmic procedures and this includes the risk of causing tissue damage because
one may not be able to eliminate any eye and head movements. One is unable to
use an operating microscope in standing procedures and only have to rely on head
loupe magnification and optics. Ophthalmic procedures are performed on very
delicate, sensitive, and thin ocular tissues, such that one wrong movement by the
horse or surgeon could cause catastrophic problems resulting in blindness and/or
loss of the globe. The surgeon should always be aware of possible head movements
and pay particular attention to approaching the eye with instrumentation and try and
do this from the sides and not directly towards the eye.
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