SASx Final Exam - Urinary System Flashcards
How do you diagnose vesicourachal diverticulum?
Positive contrast cystography
T/F: Perineal urethrostomy is successful in preventing LUT disease in cats
False
Perineal urethro_st_omy is a salvage procedure to treat FLUTDS and calculi in male cats. It increases incidence of bacterial cystitis and does not prevent FLUTDS
-
Indications for perineal urethro_st_omy in cats:
- Frequent obstructions
- Strictures
- Trauma
T/F: Urine cytology is useful for diagnosing transitional cell carcinoma (TCC)
True
30% will exfoliate cells
T/F: Even if hydronephrosis is caught late (> 4 weeks), the kidneys will likely be able to regain at least 75% function
False
If caught >4 weeks, you will be lucky to MAYBE regain 25% function
With regard to urethral surgery:
- Urine diversion (increases/decreases) inflammation.
- Catheterization (increases/decreases) inflammation.
Urine diversion decreases inflammation. Catheterization increases inflammation
What is the most common surgery performed on the urinary bladder and what are its indications?
cystotomy
- Most common surgery of the bladder
- Most common procedure for urolith removal
-
Indications:
- Urinary tract obstructions
- No medical options
- Other retreival methods have failed
What is the most common cause of ureteral trauma?
ovariohysterectomy!
T/F: Second intention healing of the urethra is the preferred method of closure for a prescrotal urethrotomy
True
- less risk of stricture and fewer complications associated with suturing the small urethral lumen*
- The down side to second intention healing is that your patient is likely to have profuse hemorrhage from the area, so they will need to be hospitalized for a few days*
What is the most common renal neoplasia seen in felines?
renal lymphoma
- Most common renal neoplasia in the cat
- MST depends on stage
- Surgery may not be indicated
T/F: Radiography is helpful for diagnosing calcium oxalate, cystine, and urate stones in the bladder
False
Cystine and urates are radiolucent!
What is the composition of more than 40% of nephroliths?
Calcium Oxalate (CaOx)
T/F: You can easily rule out bladder rupture by palpation. If the bladder is palpable, rupture is not present
False
-
In any trauma case, consider bladder rupture until you can rule it out
- Palpable bladder does not rule out
- Normal urination does not rule out
- Urine retrieval by catheter does not rule out
What surgery is being performed in this image?
partial nephrectomy
- Not often performed; technically more difficult than full nephrectomy
- Preserves renal function, but higher incidence of post-op hemorrhage
- Surgical steps:
- Occlude blood supply, Incise and peel back capsule, Pass suture with straight needle, Divide in thirds, Tighten sutures, Loosen tourniquet, Close capsule
What is the most common benign neoplasia seen in the kidneys?
renal adenoma
When closing the urinary bladder, serosa to serosa contact encourages __________, which helps ensure a water tight closure
fibrin seal
When closing the urinary bladder, serosa to serosa contact encourages fibrin seal, which helps ensure a water tight closure
T/F: Pyelonephritis is an indication for removal of the kidney
True
Where does the urinary bladder receive its nerve supply?
hypogastric n. (sympathetic) and pelvic n. (parasympathetic)
What is the most common urethrostomy site in cats?
perineal
________ urethrotomy is indicated for calculi lodged between scrotum and ischial arch
perineal urethrotomy
perineal urethrotomy is indicated for calculi lodged between scrotum and ischial arch
-
Try to avoid in dogs if possible
- Difficult procedure (urethra deeper)
- Increase risk of infection
- Usually suture urethrotomy incision
T/F: One or two layer closure is acceptable for closure of the urinary bladder
True
What is the most common urethrostomy site in dogs?
scrotal
If you suspect cystic calculi in your patient but you’re unable to view any stones on radiographs, what other diagnostic modalities are useful?
pneumocystography, double contrast cystography, ultrasound
All three are about equally effective in detecting radiolucent stones
In male cats, urethral obstruction is most often caused by:
mucus plug/crystals
Occurs most commonly in the distal 1/3 of the urethra in male cats
What size suture is typically used for closure of the urinary bladder?
3-0
Options include PDS, Monocyl, Vicryl, Dexon, Prolene, Nylon
Where is a urethrotomy typically performed in our canine patients?
prescrotal area
just caudal to the caudal aspect of the os penis (between the scrotum and the os penis)
- Very superficial area
- Less cavernous tissue
- incision is made right over the urethra
What are the indications for performing a cystopexy?
- Tube cystotomy
- Perineal hernia
- Urinary incontinence associated with pelvic bladder
When performing a prescrotal urethrotomy: after you’ve made the incision on the ventral midline, you want to isolate the __________ muscle and deviate it laterally to gain access to the prescrotal urethra
retractor penis muscle
- When performing a prescrotal urethrotomy: after you’ve made the incision on the ventral midline, you want to isolate the retractor penis muscle muscle and deviate it laterally to gain access to the prescrotal urethra*
- Once you have access, you’ll make an incision into the urethra to find the stone*
If your patient has a non-functional kidney or severe parenchymal damage, what is the surgical treatment of choice?
Nephroureterectomy
- (Surgical removal of the kidney and its ureter)*
- Neff-row-your-eat-er-ek-to-mee*
What is the treatment option for ectopic ureterocele?
Neoureterocystostomy with ureterocelectomy
knee-yo-your-eat-er-oh-sis-tossed-to-me with your-eat-er-oh-sell-ek-to-me
Progressive dilatation of the renal pelvis and atrophy of the renal parenchyma is termed:
hydronephrosis
What is the treatment of choice for persistent urachus?
surgical removal of the urachal tube
T/F: Surgical correction of the airways may be indicated in cases of urethral prolapse
True
Especially in brachycephalic breeds, this condition may be worsened by straining to breath
The urinary bladder is attached by ligaments. Which of those ligaments should be avoided during surgery?
lateral ligaments
The lateral ligaments contain the distal ureters.
What procedure is being performed here?
retrograde hydropulsion
This is performed in canine patients only!
T/F: Perineal urethrostomy is the preferred approach in the dog?
False
Only indicated when a more distal approach is not possible (tissue damaged or not possible)
Between dorsal cystotomy and ventral cystotomy, which one is preferred?
ventral approach is preferred
Increased exposure of the bladder neck, can visualize ureteral orifices
T/F: There is a very high incidence of urethral obstruction in female cats with LUTD
False
There is a very high incidence of urethral obstruction in _male cats with LUTD_
T/F: In the case of bladder rupture in a metabolically unstable animal, IV fluids are indicated
True
- Patients with bladder rupture should always be stabilized prior to surgery! It sounds counter-intuitive, but you want to give them fluids to help correct acid-base status, electrolytes, etc.*
- Often times the clinician will perform an abdominocentesis as they are giving fluids to allow the fluid to drain*
While performing a cystotomy all willy-nilly, you accidentally cut the pudendal nerve. What complication are you likely to observe in this patient?
Involuntary bladder emptying
The pudendal nerve supplies somatic innervation to the external bladder sphincter and striated musculature of the urethra
What diagnostic modality is used to confirm the exact location of ureteral trauma?
IV urography
What are some indications for a tube cystostomy?
any need for urinary diversion
Stabilize patient with LUT obstruction (cannot catheterize), bladder or urethral trauma, bladder or urethral surgery, neurologic bladders
What the f*** is that?
Giant Kidney Worm
Dioctophyme renale
What is the most common neoplasia seen in the canine urinary bladder?
transitional cell carcinoma (TCC)
T/F: Transitional cell carcinoma (TCC) is the most common urinary tract neoplasia in cats
False
- Renal lymphoma is the most common urinary tract tumor in cats
-
TCC is the most common bladder tumor in cats (and the 2nd most common urinary tract neoplasia)
- TCC seems to have an affinity for the apex of the bladder in cats (compare this to the most common location in dogs)
What is the procedure of choice for treating trauma to the proximal ureter?
ureteroureterostomy
- Procedure of choice for proximal ureter
- Cannot reimplant
- Requires magnification
- Extremely difficult
- High incidence of complications (Strictures, Dehiscence)
-
Catheterize through cystotomy
- Avoids engaging back wall with the suture
- Angle cut ends
- Suture under magnification
The most common cause of urethral obstruction in male dogs is:
calculi
In male dogs, normally at the ischial arch or just caudal to os penis
Surgical attachment of the urinary bladder to the abdominal wall is termed:
cystopexy
What is the most common urachal abnormality that we’ll see in dogs?
vesicourachal diverticulum
External opening is closed, bladder attachment patent
T/F: The procedure shown below does not cause damage to the nephrons
True
Pyelolithotomy does not cause damage to the nephrons
What are you specifically looking at when performing an abdominocentesis for confirmation of bladder rupture?
urea and creatinine
-
Urea molecule equilibrates across the peritoneum, but creatinine molecule is too large
- Urea in peritoneal fluid = serum urea
-
Creatinine in peritoneal fluid > serum creatinine
- If creatinine is higher in peritoneal fluid, then you have confirmed the presence of urine in the abdominal cavity (there would be no other reason for this fluid to have a higher [creatinine] than serum
- Potassium will also be higher in abdominal fluid
What are some predisposing factors for development of transitional cell carcinoma (TCC)?
- Obesity
- Insecticide exposure
- Herbicide
- Cyclophosphamide
T/F: Hematuria is considered an important indication for renal surgery
False
Hematuria is NOT an indication for surgery
The kidney’s blood supply comes from:
renal artery
The kidneys are usually supplied by a single renal artery, which arises from the aorta between the cranial and caudal mesenteric arteries. The renal artery divides into dorsal and ventral branches before entering the kidney at the hilus. Occasionally more than one renal artery is present (most common on left side). The renal veins empty into the caudal vena cava, caudal to the hepatic veins.
More than ____% of the urethra must be narrowed before a patient shows clinical signs of urethral stricture
60%
More than 60% of the urethra must be narrowed before a patient shows clinical signs of urethral stricture
- Creates increased risk of obstruction
-
Usually caused by trauma
- Urethral surgery
- Trauma by uroliths
- Iatrogenic from catheterization
- Healing after minor trauma
When performing a perineal urethrostomy, you want to dissect to the level of the _________ gland
bulbourethral gland
this will be your anatomical landmark to make sure you’re in that pelvic urethra where the urethra widens up significantly
This disorder is characterized by failure of one or both ureters to terminate in the normal location:
ectopic ureter
If your patient presents with an acute urethral prolapse and he’s not showing symptoms (no bleeding, ulceration, etc), what is your treatment protocol?
reduce with aid of large catheter, place purse string suture, leave for 5 days
If hydropulsion is unsuccessful, what surgical procedure is indicated for removal of urethral calculi?
urethrotomy
What is the most common clinical sign associated with ectopic ureters?
urinary incontinence
Name a few complications associated with tube cystostomy:
- Inadvertent tube removal
- Pet chewing on tube
- Breakage of mushroom tip
- Fistula formation after removal
- Urine leakage around tube
- Rectal prolapse
- Inflammation around tube site
- Hematuria
- Inadvertent tube bag removal
- Bandage sores
- Breakage of anchoring sutures
What is the most common renal neoplasia seen in canines?
renal cell carcinoma
- Increased incidence in males
- Incidence increases with age
- MST 6.8 months
- Nephroureterectomy and chemotherapy
Which of the following is NOT an indication for nephroureterectomy?
- Hematuria secondary to blunt trauma to the abdomen
- Avulsion of the renal pedicle
- Unilateral renal adenocarcinoma
- Unilateral uncontrollable pyelonephritis
Hematuria secondary to blunt trauma to the abdomen
What’s that?
One of the lateral ligaments of the bladder
This is where the ureters enter into the bladder wall, so you want to avoid these!
How do you diagnose ureterocele?
IV urography
Will see ‘cobra head sign’
Identify this non-neoplastic lesion in the urinary bladder that may be confused with neoplasia:
polyploid cystitis
What’s that?
ventral ligament of the bladder
T/F: Canine bladder tumors are very uncommon, but almost all of the occurrences are malignant
True
- Uncommon (1% of all neoplasias)
- 97% malignant
- TCC most common
- Older females (11 years)
- Seems to have an affinity for the trigone of the bladder
- Most commonly seen in Scottish terriers
What is the treatment option for intravesicular ureterocele?
Ureterocelectomy
(excision of the ureterocele)
Surgical formation of a permanent opening of the urethra at a new site is termed:
urethrostomy
-
Indications
- Permanent damage to the distal urethra
- Recurrent urethral obstruction
- Obstruction that cannot be retropulsed or removed by urethrotomy
What is the preferred method for renal biopsy?
ultrasound-guided
- Advance needle into prepared area
- Penetrate capsule
- Can identify target lesions
What is the most common type of ectopic ureter?
intramural
An intramural ectopic ureter enters the bladder at the correct location, but tunnels down the wall of the urethra before opening up.
What is the most common indication for ureteral surgery?
Ureterolithiasis
(calculi in the ureter)
Where does the urinary bladder receive its blood supply?
caudal vesicular artery and prostatic/vaginal artery
T/F: Electrohydraulic lithotripsy is a non-surgical treatment option for cystic calculi
True
T/F: Regardless of the type of stone present, dietary modification is indicated for all cases of cystic calculi
False
- Depends on the type of stone
- Incorrect diet can worsen condition!
- Patient cannot be obstructed
What is the name for this procedure that looks like a very aggressive dog-hug?
voiding hydropulsion
non-surgical treatment option for cystic calculi
- Stones must be very small (smaller than urethral diameter)
- With the patient under sedation, Inject saline into the bladder to distend the bladder. Hold the patient upright and express the bladder manually
What are the indications for renal transplants?
- Irreversible acute renal failure
- Decompensated chronic renal failure
- Polycystic disease
What diagnostic modality provides the most reliable diagnosis for bladder rupture?
positive contrast urethrocystogram
Will see leakage of contrast material in the abdomen. As it continues to leak, it will highlight the intestinal loops.
-
Other diagnostic modalities:
-
Plain radiographs
- Can see free abdominal fluid; Absence of bladder; Decreased serosal detail
-
Ultrasound
- Free fluid, concurrent injuries, guide for abdominocentesis, helps determine source of injury
-
Plain radiographs
T/F: Pyelolithotomy is contraindicated if renal disease is present
False
Pyelolithotomy is _preferred_ if renal disease is present because it does not affect RBF or GFR; does not require occlusion of blood supply
T/F: The urinary bladder usually regains 100% of its strength 2-3 weeks post-surgery
True
What is the most severe complication associated with obtaining a renal biopsy?
severe hemorrhage
When occluding the vessels of the kidney, it’s important to clamp the vessels no longer than ________. Otherwise you’ll begin to develop permanent damage to the kidney
When occluding the vessels of the kidney, it’s important to clamp the vessels no longer than 20 minutes. Otherwise you’ll begin to develop permanent damage to the kidney
This is the most common developmental abnormality of male genitalia:
hypospadias
- Incomplete formation of penile urethra, Urethral orifice can occur anywhere along penis*
- ***
Creation of a urethrostomy on the ventral body wall cranial to the pubis:
antepubic urethrostomy
-
Indications
- Recurrent pelvic urethral obstruction
- Failed perineal urethrostomy that cannot be revised
- Ventral midline in female dogs and all cats
- Parapreputial in male dogs
You’re considering ureteral surgery for your patient with a unilateral obstruction. You also find elevated BUN and creatinine. What does this indicate?
bilateral renal disease
If there is azotemia with unilateral obstruction, your patient has bilateral renal disease
Surgical incision of the renal pelvis of the kidney for removal of a kidney stone is termed:
**Pyelolithotomy**
- Can be used to remove calculi when proximal ureter and renal pelvis are dilated
- This area is hidden by kidney when not dilated
- Does not require occlusion of blood supply
- Does not damage nephrons
- Longitudinal incision
- Catheterize and flush ureter
How do you diagnose urethral trauma?
positive contrast urethrogram
Plain radiographs are non-diagnostic!
What is the most common cause of renal trauma?
hit by car (blunt trauma)
- Most commonly from HBC/blunt trauma
- Hematuria is not indication for surgery
-
Diagnosis
- Contrast excretory urography
- Exploratory celiotomy
- Ultrasound
T/F: If hydronephrosis is caught early (< 1 week), the kidney will likely regain full function
True
Especially if it’s just a partial obstruction
Is there a higher incidence of urine scald with a scrotal urethrostomy or a prescrotal urethrostomy?
prescrotal urethrostomy
__________ is the holding layer/layer of strength of the urinary bladder
submucosa!
(just a reminder in case it definitely comes up again… the submucosa is also the holding layer in the esophagus… and really pretty much all the inside things)
What is the main goal of perineal urethrostomy?
mobilization of the urethra
T/F: After performing a nephrolithotomy, the kidney can be closed using “sutureless closure”
True!
-
Sutureless closure
- Hold for 5 minutes
- Forms fibrin seal
- Suture capsule only
- Release vascular clamp
Treatment for ureteral trauma is based on time, location, and severity. What surgical treatment is typically the least expensive and minimizes complications?
Nephroureterectomy
Other options include ureteroureterostomy (ureteral anastomosis), neoureterocystostomy (ureteral reimplantation), urinary diversion
Formation of a cyst along the urachus is termed:
urachal cyst
you’re welcome.
- Secreting urachal epithelium persists
- Usually isolated segment
- Usually asymptomatic
- Surgical excision if clinical signs develop
