Case Report
Field management of equine uterine prolapse in a
Thoroughbred mare
R. C AUSEY *, D. R UKSZNIS?
AND R. M ILES ?
Department of Animal and Veterinary Sciences and the Maine Agriculture and Forestry Experiment Station, University
of Maine, Orono, Maine 04469-5735; and ?Foxcroft Veterinary Service, Dover-Foxcroft, Maine 04426, USA.
Keywords:
horse; uterus; prolapse; abortion; laminitis; metritis
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Introduction
Uterine prolapse is a medical emergency in the mare and is
often fatal as a result of complications such as peritonitis
following uterine laceration, uterine artery rupture or systemic
shock. Mares of all types from draught breeds to ponies appear
susceptible to uterine prolapse. The management of uterine
prolapse and related conditions have been previously described
(Pascoe and Pascoe 1988; Blanchard and Varner 1993; Hooper
et al.1993a,b; Perkins and Frazer 1994; Frazer 2003a,b).
This report details an aged Thoroughbred mare who
aborted twin fetuses at 9 months gestation and the
resulting treatment and outcome.
Case details
A 15-year-old multiparous Thoroughbred mare, weighing
approximately 550 kg, at 9 months gestation with twins, was
found in her stall by an attendant at 07.00 h, having aborted
twin fetuses. The fetal membranes, still attached to the uterus,
were wrapped around the hind legs of the vocalising, circling
mare. The attendant noted a mass protruding from the vulvar
lips. The mare was walked to an indoor arena where,
vocalising and straining, she prolapsed the entire uterus. The
attending veterinarians were contacted and instructed the
attendant to elevate and pack the exposed uterus in a plastic
bag. The attendant proceeded to do so, securing the bag to a
braid in the tail, to protect and elevate the uterus. However,
the mare then went down in lateral recumbency.
Treatment
The attending veterinarians reached the mare approximately
30 min after the prolapse. The mare, still in lateral
recumbency, received 5 l of sterile fluids i.v., 5 mg (9.1 ?g/kg
bwt) detomidine and 500 mg (0.91 mg/kg bwt) flunixin meglumine i.v. Euthanasia was discussed with the owner, but
it was decided that the mare might respond to reduction of
the prolapse and medical therapy.
The uterus was cleansed with sterile saline. It appeared
intact, with no lacerations extending into the myometrium,
although the endometrium appeared congested and abraded,
with significant haemorrhage. The free portions of the fetal
membranes were removed, and a large amount of adherent
fetal membranes left in place. The prolapse was then reduced
with relative ease using a commercial sterile lubricant (Priority
Care)
1. Within minutes of reducing the prolapse the mare
stood, vocalised, but exhibited knuckling of both rear fetlocks.
Complete reduction of the prolapse was confirmed by
intrauterine palpation. The mare?s heart rate was 84 beats/min
and temperature 35.9?C. An additional 10 l of fluid was
administered i.v. and the mare received 2 g (3.64 mg/kg bwt)
gentamicin i.v. and 50 iu (40 iu/450 kg bwt) of oxytocin i.m.
She was depressed throughout the day and was wrapped in
blankets with heated padding (ambient temperature, -23?C).
She drank a little water when offered to her, but did not
urinate or defaecate during the day. At 16.00 h she exhibited abdominal discomfort, heart rate
was 120 beats/min and rectal temperature 35.9?C. She had
not urinated since the prolapse. It was felt that uterine
haemorrhage might have contributed to the severely elevated
pulse, and the mare was transfused with 1.5 l of whole blood
(supplies to administer a larger volume were not available).
A blood sample collected prior to transfusion exhibited a PCV
of 30% when results were obtained the following day. She
received a further 5 l of fluids i.v., 6 million iu (11,000 iu/kg
bwt) of procaine penicillin G i.m., 500 mg (0.91 mg/kg bwt)
flunixin meglumine i.v., and 20 iu (16 iu/450 kg bwt) oxytocin
i.m. to aid passage of the retained fetal membranes. Transrectal ultrasound revealed a moderately distended
bladder, ruling out rupture of the bladder as the cause of
anuria since the prolapse, but giving rise to concern that
urination might be impaired if the bladder or urethra had been
traumatised by prior inclusion in the prolapse.
*Author to whom correspondence should be addressed.
EQUINE VETERINARY EDUCATION / AE / June 2007