SURGERY
Figure 1 . If the bladder and the proximal urethra lies intraabdominally , then any increased abdominal pressure will cause equal pressure on the bladder wall as well as on the urethra .
Figure 2 . If the bladder is located intra-pelvic , the abdominal pressure is only active on the cranial bladder wall and forces urine out of the short urethra , making the dog incontinent . abdominal position by means of a colposuspension or with an urethropexy 9-11 . Colposuspension provides firmer anchorage of the lower urogenital tract than urethropexy and it also avoids urethral trauma 11 .
1 . Colposuspension
This moves the bladder neck cranially and relocates the bladder in a more intra-abdominal position to improve transference of abdominal pressures to the bladder neck and proximal urethra 2 , 3 .
This operation was developed for woman with stress incontinence and is used in bitches with USMI since 1985 2 . The vagina on either side of the urethra is anchored to the pre-pubic tendon with nonabsorbable monofilament nylon sutures 2 , 3 .
Surgical technique
The bitch is placed in dorsal recumbency and an 8FG Foley catheter ( smaller bitch ) or 10FG ( larger bitch ) is inserted through the urethra into the bladder . The cuff is inflated and the catheter gently withdrawn until its cuff rests in the bladder neck . The catheter facilitates identification of the urethra and bladder neck during surgery .
A caudal , midline abdominal approach just cranial to the pubis , is made and the linea alba is incised caudally to the level of the pelvic brim . The prepubic tendons and external pudendal vessels are identified so they can be avoided .
Cranial traction on the bladder with a stay suture allows the bladder neck with the inflated Foley catheter cuff to be identified . The retroperitoneal fat around the bladder neck and urethra is gently rubbed off with a swab twisted around a straight Spencer Welch artery forceps . ( Fig 3 a , Fig 3 b )
The vagina is displaced cranially with a gloved finger inserted into the vagina ( large bitch ) or a well-lubricated test tube or Poole suction tip ( smaller bitch ) 11 . The urethra is palpated through the ventral vaginal wall and displaced to the left side of the patient while the vaginal wall over the fingertip to the right side of the urethra is pushed cranially towards the caudal aspect of the linea alba incision . The exposed vaginal wall is now grasped with an Adson tissue forceps
Figure 3a . Bladder position before traction cranially
Figure 3b . Bladder position after traction
Issue 02 | MAY 2018 | 31