12 UT2 Kidneys and incontinence

Be able to discuss the surgical anatomy of the kidneys and when/how to perform a nephrectomy • Be able to discuss how to work up an incontinent dog to achieve a diagnosis of USMI vs ectopic ureters • Be able to discuss the surgical treatment options for USMI, understand the limitations of each option and understand how to manage a patient with this condition • Understand the difference in management options for USMI between female and male dogs and feline patients

surgical anatomy of kidney

R kidney more cranial to L

ureter from kidney to urinary bladdder, hook, enter trigone region

one more renal artery/vein for each kidney

left ovarian gonard artery comes off renal artery

Uretero-nephrectomy indications

Unilateral renal disease • Neoplasia • Irreparable trauma • Persistent pyelonephritis – e.g. associated with nephroliths

Hydronephrosis

• Ureteral abnormalities – Obstructive calculi

nephtolithiasis (uncommon)

• usually medical meange or leave unless causing problem

Nephrolithiasis prevalence

• 5 to 10% of all uroliths •

Generally incidental

May be amenable to dissolution• Treatment options:

Nephrolithiasis tx

• most common

– Shock wave lithotripsy (refer to RVC)

Nephrotomy ( if clinical sign)

Uretero-nephrectomy

• ususllly end stage and non functional kidney

• Severely hydronephrotic

• Persistent infection

Uretero-nephrectomy

ventrla midline approach

1. identify kidney with duodenal/ colonic nerves

2. kidney sit in fatty pounch (retoperitoneal flat)—> blunt dissect kidney w digit

3. identify arterys and veins. —> thicker is artery, ;

4. circumfrential/ transfixing suture to ligate ligate a first (prevent engorgement)

   • remember to place ligature on each side and resect in between

5. elevate kidney, dry swap all the way down ureter down bladder

6. suture x2, resection as close to bladder as possible

Urinary incontinence ddx

• • Congenital abnormalities

  • Ectopic ureter

  • Congenital urethral sphincter incontinence

• Urethral sphincter mechanism incompetence (USMI)

• Inflammation

• Neurogenic abnormalities

• Behavioural problems

Ectopic ureter

prevalence: sex

breed

Congenital, incontinent since birth. Occasional adult-onset

• Females > males

• Retrievers, Poodles, Huskies

Ectopic ureter - 2 types

can empty into urethra, vagina or uterus. can be unilateral or bilateral.

extramural : completely bypass bladder

intramural: enter bladder at region of trigone but not into luman. carryon submucosally and enter into urethra

Ectopic ureter - presentation 4

• Continual dribbling of urine

• Urine scald

• Unilateral: can pass stream of urine: bilateral may have no bladder filling

Ectopic ureter • Associated urogenital abnormalities:

• Urethral sphincter incompetence

• Congenital renal abnormalities (esp retriever)

• Bladder hypoplasia

• UTI + pyelonephritis

• Hydroureter

ureter peristaltic rate

one a minute

Ectopic ureter - diagnosis

• Evaluate renal function – CBC/chem, urinalysis

• Evaluate for UTI – urine C&S

• CT excretory urography – most sensitive method

• Contrast radiography – IV urogram with pneumocystogram

• Cystoscopy (fancy)

• Ultrasonography

contrast radiography. what does this px have

air -ve contrast

whats wrong with this patient

ectopic ureter— hydroureter

ectopic ureter treatment of choice

surgery

Ectopic ureter – surgical treatment

Intramural

• Laser ablation

• Neoureterostomy

• Ureteroneocystostomy

Extramural

• Ureteroneocystostomy

Unilateral end-stage renal disease

• Uretero-nephrectomy

INtramural tx: Neoureterostomy – new stoma

1. creaete incision over oureter

2. create a new home: suture urothelium of ureter to the urothelium of the bladder

3. pass urinary cat through distal segment, pass suture between submucosal shelf and outside wall

4. take cat out, tighten suture

extramural ureter: Ureteroneocystostomy

1. stay suture at diatl portion of ureter

2. suture up defect region in urethra

3. create a hole

4. pull ureter through into urinary bladder lumen

• create spatulation to make surface area of hole larger

1. simple interupted suture—> urothelium to urothelium

—> refer

USMI Urinary sphincter mechanism- Pathophysiology

Urethral tone and length – Bladder neck position – Body size and breed – Gonadectomy

neck of urinary bladdder within abdomen: pressure is the same

older—> shorter urethra—> neck is out of abdo cavity—> incontinence

— usually older, F, N

USMI - diagnosis

History – Predominantly incontinent when recumbent – May occur after spay •

Rule out other causes incontinence– CBC/chem, urinalysis, urine C&S– repirical Medical management – CT excretory urography – Cystoscopy

USMI – medical management

• 4 treatment, which one to try

• cure rate of single therapy treatment

do not become continent but often improve

1. Oestrogens *

2. a-adrenergic agonists : Phenylpropanolamine *

3. Weight loss *

4. Control of urinary tract infections

*reduce dose, side effect; increase response

cure rate of ~50%

USMI – surgical management approached

• indication: if no response to medical treatment

• common

• Colposuspension

• Pexy: Urethropexy / Cystourethropexy

• Submucosal urethral bulking agent injections— collagen (6months effect)

• Artificial urethral sphincter

• Transobturator vaginal tape

USMI – surgical management: Colposuspension

• goal

Increase urethral length

Relocate bladder neck to intraabdominal position

Increase pressure at bladder neck

USMI – surgical management: Colposuspension

• outcome

50% cure, 40% improve, 10% no response

Colposuspension- referrla

• Sutures from the cranial vagina to the prepubic tendon on either side of the proximal urethra—> increase pressure

• permenant, nonabcsorbable suture

Colposuspension normal complication: 11-15%

• Pollakisuria— if it is pulled really tight

• Recurrent UTIs

• Slight tenesmus

• Pain during first defaecation

USMI – surgical management: (Cysto)urethropexy (uncommon)

• what is it? 2

• complications

• outcome 2

1. Pexy bladder more cranial to abdominal wall

2. Suture ventral wall of proximal urethra to prepubic tendon

Complications – Pollakisuria – Dysuria

Outcome:

• Sole technique: 53% complete continence

• Combined colposuspension: 70% complete continence

USMI – surgical management: Bulking agents

• goal

Endoscopic submucosal injections of collagen to increase urethral resistance

USMI – surgical management: Bulking agents

• success rate

• recurrence?

50-70%

recurrence 1m-1y

USMI – surgical management: Artificial urethral sphincter

• name 1 advantage

increase urethral resistance

• Cuff placed around proximal urethra

• Urethral compression can be increased by injecting saline into subcutaneous port

advantage: can monitor and manage subcutaneously post op if needed

disadvantage: FB complication, have to dissect around urethra: damage to BS—> necrosis

Artificial urethral sphincter • Complications:

UTI up to 67%

Urethral obstruction 7-17%

Infection port site

Accidental puncture device

Artificial urethral sphincter: Outcome:

• 36-56% complete continence

• 67-92% functional continence

USMI is rare in male dogs.

• aetiology

Congenital – Pelvic urethral dilatation – Prostatic diverticulum

Acquired – Larger breeds – Neutering – Intrapelvic bladder

USMI in male dogs - treatment outcome vs cat

Treatment less successful than in females

USMI in male dogs - treatment

• medical

– a-adrenergic agonists

USMI in male dogs - treatment 3

Vas deferens pexy to abdominal wall

Prostatopexy to prepubic tendon

artificail urethral sphincter

USMI in cats is very rare why?

Continent zone’ longer and stronger in cats

• Smooth muscle

• Striated muscle

• Fribroelastic tissues

USMI in cats treatment— surgery

Artifical urethral sphincter

Excision caudal portion ventral wall bladder

Excision of the caudoventral portion of the bladder

uncommon

basically creater longer urethra and increase resistance