Page 494 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Reproductive system: 2.1 The female reproductive tr act 469

VetBooks.ir involvement will usually require surgical treatment 2.76
via an exploratory laparotomy.
Prolapsed bladders can be replaced after drainage
of the urine via catheter or needle. Initial emergency
treatment is followed up by continuing small doses
of oxytocin, based on the degree of involution, and
fluid therapy, broad-spectrum antibiotics, and anti-
endotoxic therapy, depending on the clinical signs of
the mare. Uterine lavage is continued daily until the
recovered fluid is clear.

Prognosis
The prognosis varies from guarded to grave depend-
ing on the degree of prolapse, the damage to the
uterus, secondary problems such as ruptures or ves-
sel damage, and secondary complications such as
shock and metritis. Death can occur sometimes even
prior to examination. Metritis following replace-
ment is common, and requires early aggressive treat-
ment. The incidence of prolapse is not increased in
subsequent pregnancies.

BLADDER EVERSION AND PROLAPSE Fig. 2.76 A mare with bladder eversion post foaling.

Definition/overview
These are rare conditions in the horse. They are prolapse involves emptying and cleaning the bladder
more common in larger mares, particularly the before replacing it back into the abdomen via the tear,
draught breeds. which is subsequently repaired surgically. In cases of
eversion the bladder is emptied, any defects repaired
Aetiology/pathophysiology and the bladder lubricated before careful replace-
Bladder eversion or prolapse usually occurs subse- ment back through the urethral opening. In some
quent to post-partum straining due to reproductive cases, swelling and oedema of the bladder require
tract injuries, dystocia, retained placenta or rectal that it is pressure wrapped in a dextrose solution-
impaction, although it has also been seen in mares soaked, cool, soft cloth to reduce the fluid content of
pre-partum. In prolapse, the bladder is forced through the bladder wall prior to replacement. Occasionally,
a tear in the ventral vaginal wall. In eversion, the blad- a loop of bowel becomes trapped behind the blad-
der is everted through the urethral opening. der, preventing replacement. This can be identified
on ultrasound. The urethra may require surgical
Clinical presentation enlargement and subsequent repair if it is too narrow
Clinical signs in bladder prolapse are of a bladder to allow replacement. Following replacement, the
with its serosal surface exposed, usually at the vulval cause of any initial straining must be treated, blad-
lips, while in an eversion the mucosal surface is pre- der straining prevented by epidural anaesthesia,
sented with the ureteral openings visible (Fig. 2.76). and/or nasotracheal intubation and broad-spectrum
antibiotics and NSAIDs administered. Placement
Management of a wide bore in-dwelling urinary catheter should
Treatment is usually undertaken with epidural anaes- be attempted; however, if this leads to straining,
thesia in the standing sedated animal. Treatment of it should be removed.