Urinary - Kidneys And Ureters

Question 1

What is the anatomical significance of the inner medulla of the kidney with regard to surgical approach?

Answer 1

Inner medulla:

• collecting ducts
• renal pelvis*

*location of Renal a., v., and ureter;
It’s NOT uncommon when the renal a. enters at the renal pelvis to bi-or-TRI-furcate—> need to ligate those multiple aa. OR ligate more proximal to those aa.

Question 2

If we must make an incision on the kidney, what do we need to keep in mind and where do we cut?

Answer 2

When blood supply hits the kidney, it DOESN’T cross the sagittal plane - so we want to make the incisions here to minimize hemorrhage

Question 3

If you’re performing a nephroureterectomy in an INTACT patient, what do we need to be mindful of?

Answer 3

If we’re removing the LEFT kidney, remember that the left ovarian/ left testicular vein come off of the left renal vein —> we need to preserve the venous supply by ligating CLOSER TO the kidney!

Question 4

Term we use for cutting into the kidney parenchyma itself…

Answer 4

Nephrotomy

Question 5

Term we use for making a surgical incision into the renal pelvis area…

Answer 5

Pyelolithotomy

Question 6

What is a nephrostomy tube?

Answer 6

Tube from the kidney to the external env’t

Question 7

If you plan to remove stones via nephrolithotomy, what is IMPERATIVE to do?

Answer 7

Check CONTRALATERAL renal function!

• GFR
• excretory urography

BECAUSE: every time you do surgery, you run the risk of damaging the ipsilateral/affected kidney

Question 8

Concerning nephrolithotomy, once we remove the stone(s) and submit for culture/sensitivity/analysis, and culture the renal pelvis, what do we need to do to try and minimize the chance of clot formation?

Answer 8

Flush renal pelvis with heparinized saline to make sure the ureter is patent going all the way to the bladder!
*clot formation in the renal pelvis will lead to hydronephrosis

Question 9

How long is vascular clamp time before we start to see renal damage in the case of nephrolithotomy?

Answer 9

20 min!

Question 10

When would a pyelolithotomy be a better choice than a nephrolithotomy to remove kidney stones?

Answer 10

When calculi in renal pelvis is present and the pelvis is dilated and if the stone isn’t deep into the parenchyma

no vascular occlusion and no damage to functional renal tissue (nephrons)

Question 11

In the case of hydronephrosis by obstruction, what is the time frame for complete resolution? Otherwise?

Answer 11

<1 week obstruction—>complete resolution

> 4 week obstruction—> MAY regain 25% :(

Question 12

What is the most common renal neoplasia in the dog?

Answer 12

Renal cell carcinoma

increased incidence in males, with age

Question 13

What is the treatment for Renal Cell Carcinoma?

Answer 13

Nephroureterectomy and chemotherapy

Question 14

What’s the most common renal neoplasia in the cat?

Answer 14

Renal lymphoma - surgery usually not indicated

Question 15

In screening for renal transplant patients, what do we require for them to qualify?

Answer 15

PCV>30%
Crea <8 mg/dL
BUN <100 mg/dL

otherwise, need EPO, fluids, etc. to get them to acceptable levels

Question 16

When do we treat renal transplant patients with immunosuppression therapy?

Answer 16

24-72 hours PRIOR to surgery, continued after surgery…

Question 17

Term for transplanting the distal ureter into a new place in the bladder?

Answer 17

Neoureterocystostomy

Question 18

Term for transplanting the ureter into another place (bladder, urethra, etc)?

Answer 18

Neoureterostomy

Question 19

Term for cutting into the ureter?

Answer 19

Ureterotomy

Question 20

Term for resection/anastomosis of ureter?

Answer 20

Ureteroereterosotomy

Question 21

What are the most common abnormalities associated with an ectopic ureter?

Answer 21

Hydroureter
Small/absent kidney
Pelvic bladder

Question 22

What is the most common signalment/clinical signs associated with ectopic ureters?

Answer 22

Siberian huskies, labs, golden retrievers, WHWT

CS: young 6-8 week old puppy that is dribbling urine; consistent incontinence and dermatitis (urine scald)

Question 23

How do we determine the extent of ureteral damage?

Answer 23

Observe for urine leakage - if present, need to intervene

Question 24

As far as performing a resection anastomosis of the ureter, what is the procedure of choice for injury the proximal ureter and why?

Answer 24

Ureteroureterostomy;
because at the level of the proximal ureter, you don’t have enough ureteral length to re-transplant that ureter into the bladder

Question 25

What is the purpose of a urinary diversion procedure in the treatment of ureteral trauma?

Answer 25

To help minimize the amount of urine that is flowing across that anastomosis site (which would cause urine leakage/potential dehiscence)

Question 26

In regards to medical management, what are reasonable choices in dealing with ureterolithiasis?

Answer 26

*IV fluids + diuretics
=increase flow in the hopes of moving the stone(s) to the bladder

*smooth muscle relaxers: glucagon, amillotriptoline?

Question 27

What are ureterolithiasis indications for surgery/lithotripsy?

Answer 27

Complete obstruction
Azotemia
Pyelonephritis
After 2 weeks of unsuccessful medical management

Question 28

With regard to presurgical considerations for ureterolithiasis, what pre-existing pathology do most cats have, unrelated to obstruction?

Answer 28

Interstitial nephritis

Question 29

What is lithotripsy?

Answer 29

Using shockwaves (basically) to make stones smaller
(Non-surgical)

*not always effective