Page 240 - Manual of Equine Field Surgery
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CHAPTER 43
Rectovaginal Fistula Repair
John C. Janicek
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is confirmed, the tail is wrapped and securely
INDICATIONS
retracted. Fecal material is removed from the
rectum and vagina. The perineal region is rinsed,
Dystocia, traumatic breeding, or unsuccessful followed by cleansing of the rectum and vagina
third-degree perineal laceration repair resulting in with a dilute povidine-iodine solution. The per-
rectovaginal fistula formation.
ineal region is then aseptically prepared. The
preparation solution should be rinsed with sterile
saline, not alcohol, as alcohol may cause excessive
EQUIPMENT irritation.
Long-handled instruments and monofilament
absorbable suture materials are required. An 80- PROCEDURE
degree scalpel handle is helpful for the direct
repair technique described. Self-retaining retrac- Various repair techniques are described. Princi-
tors (Balfour, modified Finochietto) and a good ples for all techniques include complete debride-
light source (floor lamps, headlamp, or fiberoptic ment of the fistula margin, minimal tension on
lights) are useful but not required. the repair, and maintaining a soft manure consis-
tency after surgery. Modification of the techniques
can be performed based on surgeon preference.
PREPARATON AND POSITIONING
I
Direct Repair
Surgery is delayed for 4 to 6 weeks following
fistula formation to allow wound contraction and Fistulas up to 10 cm have been repaired using this
1
inflammation to subside. Delaying surgery for this technique. This technique preserves the per meal
period allows the wound edges to strengthen and body and anal sphincter, resulting in good
become clearly defined before repair is attempted. primary healing and rninimal swelling and pain
A gruel or pasture diet is fed 3 to 5 days prior to after surgery. Complete fistula margin debride-
surgery, and the mare is fasted 1 day before ment, which can be difficult in cranially located
surgery. fistulas, is the major limitation of the direct repair.
The repair can be performed with the horse The anal sphincter is dilated with self-retaining
standing or under general anesthesia. For stand- retractors or by placing umbilical tape through the
iI1g procedures, the mare is restrained in a stock, anal sphincter 2 cm lateral to each side of dorsal
and surgery is performed following epidural anes- midline and securing the tape around the base of
thesia, and sedation if necessary. Once anesthesia the tail. Towel clamps or retention sutures are
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