Page 226 - Manual of Equine Field Surgery

CHAPTER 41

Urethral Extension (Urethroplasty)

John C. Janicek

INDICATIONS extending from the urethral orifice to near the

mucocutaneous junction so that urine enters the

vagina caudal to the brim of the pelvis, allowing
Urine pooling, urovagina.
gravity to assist in voiding urine. 111 all techniques,

it is important to place the first suture cranial to

the urethral orifice to minimize the risk of fistula

EQUIPMENT formation and to appose the dissected tissue

shelves with minimal tension. Adequate visualiza-

Long-handled instruments and a 30-Fr Foley tion is achieved by use of a vaginal spatula posi-

catheter are required. Self- retaining retractors tioned along the dorsal aspect of the vaginal

(vaginal spatula, Balfour, modified Finochietto) lumen along with ventrolateral placement of

and a good light source (floor lamps, headlamp, towel clamps in the vulvar labiae. Retraction may

or fiberoptic lights) are useful but not necessary. also be provided using Balfour or modified

Finochietto retractors.

PREPARATION AND POSITIONING Monin Technique

This technique involves caudal translocation of
The mare is restrained standing in a stock, and

surgery is performed following epidural anesthe- the transverse urethral fold':' and is recom-

sia, and sedation if necessary. Once anesthesia is mended only in cases with mild perinea! confor-

confirmed, the tail is wrapped and securely mational abnormalities. The major limitation of

retracted. Fecal material is removed from the this technique is the inability to extend the ure-

rectum. The perinea! region is rinsed, followed thral opening as far caudally as can be done with

by cleansing of the vaginal lumen with a dilute other techniques, which is necessary in mares with

povidine-iodine solution. The perineal region is moderate to severe perineal conformational

then aseptically prepared, with care taken to not abnormalities.

use alcohol, as it may cause excessive irritation. The transverse urethral fold is grasped with
Allis tissue forceps 1 cm abaxial to each side of

midline and retracted approximately 5 cm cau-

dally. The lateral aspect of the transverse urethral

PROCEDURE fold is split horizontally and the incision is

extended along the corresponding ventrolateral

Various repair techniques are described. The goal vaginal wall (Figure 41-1). The transverse urethral

of all techniques is to create a mucosal tunnel fold is sutured to the vaginal floor in the retracted

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