Bladder and Urethra (E1) Flashcards
What nerve(s) supply the bladder?
Sympathetic: Hypogastic Ns
Parasympathetic: Pelvic N
Somatic: Pudendal N (to sphincter and urethra)
What is the vascular supply of the bladder?
Main supply: Caudal vesicular artery (from vaginal/prostatic artery)
Cranial vesicular artery (from umbilical artery)
What are the types of urachal abnormalities? (2 common, 2 rare) Which is the most common?
Vesicouracheal diverticulum (most common)
Persistent urachus
Urachal cyst- rare
Urachal sinus- rare
How is a persistent urachus diagnosed? How is it managed?
Dx: Place contrast in umbilicus
Tx: Surgical removal of urachal tube
How is a vesicouracheal diverticulum diagnosed? How is it managed? Why is it important to treat it?
Dx: Positive contrast cystography
Tx: Partial cystectomny and diverticulectomy
Predisposes to uroliths and UTI due to urine pooling
What is the most common cause of bladder rupture? What are some other causes?
Most common: Trauma
Severe cystitis
Neoplasia
Urethral obstruction
Iatrogenic
How could you diagnose a ruptured bladder (4 ways)?
Plain radiographs -Look for abdominal fluid, absence of bladder, decreased serosal detail
US - Look for free fluid, concurrent injuries (Can be used to guide abdominocentesis and determine source of injury)
Positive contrast urethrocystogram - MOST RELIABLE
Abdominocentesis- Urea in fluid = serum urea, CRE in fluid > serum CRE, high K in fluid
What are the indications of a tube cystotomy?
To stabilize a patient with LUT obstruction that cannot be catheterized
Bladder/urethral trauma or surgery
Long term for neurologic bladders (usually use a low profile tube cystotomy)
What suture do you place prior to making a stab incision for a tube cystotomy? Where do you make the incision? Which catheters can you use and which one does Betance prefer?
Purse-string suture Incision made between the purse strings
Foley (preferred) and Mushroom tip
What are the complications for a tube cytotomy? Are these common?
- Inadvertent removal (that’s why always use e-collar and abdominal bandage)
- Pet chewing on tube
- Breakage of mushroom tip
- Fistula formation after removal
- Urine leakage around the tube (usually caused by purse-strings being too lose)
High complication rate
What are the indications for a cystopexy? What are you “pexy”-ing (what to what)? How many lines of sutures do you make?
- Tube cystotomy
- Perineal hernia
- Urinary incontinence associated with pelvic bladder
Suture bladder wall to abdominal wall
2 lines of sutures (use 3.0 monofilament absorbable or non-absorbable)
What are the most common types of cystic calculi?
Calcium oxalate (most common)
Struvite
How are cystic calculi diagnosed and what clinical signs are associated with them?
Dx: Plain radiographs, Pneumocystography, Double contrast cystography, US
CS: large thick bladder +/- palpable calculi, UTI common, other LUTD signs
What are the non-surgical management options for cystic calculi? Mention advantages and disadvantages for each.
Hydropropulsion
(+) Way to remove stones without surgery
(-) Can irritate/traumatize bladder/urethra, may take several attempts, only for small stones, could cause urethral obstruction
Transurethral cystoscopy
(+) Way to remove stones without surgery
(-) Urethral irritation, may need to repeat often if there are multiple stones, only for small stones, not for smaller patients
Electrohydraulic lithotripsy
(+) Way to remove stones without surgery, can make the stones smaller so that other non-surgical removal could be done
(-) May not be available
Dietary modification
(+) Non-surgical, easily implemented
(-) Only works for certain stones, better as prevention not treatment
When is surgery indicated for cystic calculi? How is the procedure performed and how would you close (include suture options, patterns and closure techniques)?
- UT obstruction
- If no other medical/non-surgical options worked
Most common surgery = CYSTOTOMY
Either dorsal approach or ventral (better because can visualize ureteral orifices)
SX:
- Caudoventral midline approach
- Moisten lap sponges
- Empty bladder
(3a. ) (Drape prepuce) - Transect ventral ligament (dont touch lateral ligaments)
- Place stay sutures on lateral aspects and apex (for handling bladder)
- Stab incision at apex
- Extend incision with scissors
- Evert walls and inspect
- Remove calculi
- Pass urethral catheter, flush to ensure patency
(Submit urine, stones, and mucosal tissue for C/S)
- Close (see below)
- Leak test bladder
- Post-op rads
(Expect to heal 14-21 days post-sx)
Closure
Water tight - good apposition, invert tissye so you close serosa to serosa (encourages fibrin seal) if possible
Do not penetrate the lumen with the sutures
Avoid impingement of ureters
Always engage submucosa (layer of strength)
Suture: PDS, Monocryl, Vicryl, Dexon, Prolene, Nylon (NOT BRAIDED - dissolves in urine)
Patterns: Many patterns successful, no influence on bursting strength
- Most water tight: One or 2 layer inverting pattern - Cushing followed by Lambert
- One or 2 layer appositional pattern - Simple continuous in submucosa followed by simple continuous in seromuscular layer
- Simple continuous in submucosa followed by Cushing
Fill in the blanks
Detrussor muscle
Ureter
Ureteral opening
Trigone
Name the non-neoplastic bladder disease affecting the mucosa for which surgery is curative. A biospy confirms the diagnosis.
Is it more common in males or females?
Polypoid cystitis
Females
What is the most common bladder tumor in the dog and cat?
What is the most common urinary tract tumor in the dog and cat?
Bladder (dogs and cats): Transitional Cell Carcinoma (TCC)
UT: Dog- TCC, Cat- Renal lymphoma
What is the typical signalment for dogs and cats who develop TCC?
Dogs: Older females (11y)
Cats: Middle-aged males
In cats TCC’s tend to be found in the ____ of the bladder, while in dogs they tend to be found in the ____.
Apex
Trigone
What are the predisposing factors for TCC? Which dog breed is predisposed to them?
Obesity
Insecticide exposure
Herbicide Exposure
Cyclophosphamide
Scottish Terriers
The clinical signs associated with TCC are similar to _____. Metastatic disease can result in _____ and _____.
LUDT
Lameness
Coughing
What modalities can be used to diagnose TCC? Is FNA indicated? Which test is used as a screening modality and why?
Positive contrast rads
US (evaluate LN’s)
Transurethral biopsy
BTAT used are screening test because of the high rate of false positive
The risk of performing a partial cystotomy (with >1cm borders) to remove a TCC is the occurance of __________. When the trigone is involved, salvage procedures such as ________ or ________ can be performed.
Tumor seeding
Ureterocolonic anastomosis
Ureterouterine anastomosis
T/F: Chemotherapy with agents such as piroxicam, cisplatin and mitoxantrone can be administered to treat TCC either in conjunction with surgery or not.
True
What is the most common developmental abnormality of male genitalia which involves the incomplete formation of the penile urethra? Which breed is predisposed to it?
Hypospadias
Boston terriers
What is the protrusion of urethral mucosa through the orifice called? What clinical signs are associated with this?
Urethral prolapse
CS: Bleeding from prepuce, licking, red-purple mass
How would you manage a dog with a mild urethral prolapse (2 surgeries) ? What adjunct therapies might you recommend/perform?
Reduce and purse string
Urethropexy (using groove director which guides the scalpel and prevents it from going all the way through the penis; full thickeness sutures are placed through penile wall and urethra)
Adjunct: Castration, Airway surgery (for BAS)
What are the predisposing causes fo urethral prolapse? What is the typical signalment?
Straining (UTIs)
Brachycephalic airway syndrome (Dyspnea)
Sexual excitement
Sig: Young male brachycephalic dogs
A dog presents with a urethral prolapse. The protruding tissue is necrotic and ulcerated. What treatment is indicated?
Resection and anastomosis
- Catheterize
- Tourniquet
- 180 degree incision (to prevent mucosal retraction)
- Suture (monofilament absorbable, NOT BRAIDED)
What are the clinical signs of urethral trauma? How is it diagnosed?
Hematuria
Stranguria
SQ or abdominal fluid accumulation
Signs of azotemia
Dx: Positive contrast urethrogram (confirms presence and location)
Plain radiographs are non-diagnostic
What are the treatment options for an incomplete or small lacerations of the urethra? What is required if the rupture is complete?
Incomplete: Urinary diversion with urethral catheter or cystotomy tube
Complete: Anastomosis or repair with urinary diversion
When placing a urethral catheter to allow a laceration to heal, at least how long must the catheter stay in place? What risks are associated with catheterization?
3 weeks
Stricture formation
Urethral obstruction is common in dogs and cats. In cat the obstruction usually occurs ________ and is caused by ____, _____, or _____. In dogs the obstruction usually occurs ________ and is caused by ____,
Cats: Distal 1/3 of urethra- mucus plugs, crystals, stones
Dogs: Ischial arch/ caudal penis - stones
How could you diagnose a urethral obstruction? What can you do to temporarily relieve the obstruction? What else must you normalize and how?
Dx: Plain radiographs (might see calculi or bladder distention), US, Contrast radiography
Temporary relief: Catheter (to bypass stone or push stone into bladder), Hydropropulsion, Cystocentesis (only if cath not possible)
Tx: Must stabilize patient - Normalize e-lytes and treat uremia by giving IVF (ASAP, uremia occurs quickly approx 12-24 hrs), treat UTI
What is the technique called where saline is injected to force a stone out of the urethra into the bladder?
Retrograde hydropropulsion
What catheters can be used in cats to perform retrograde hydropropulsion?
Tomcat
Slippery sam
Red rubber
Why would you perform a urethrotomy in a dog? Where is the best place to make your incision and why? What is the other approach and when would you perform the surgery in that way? What is the preferred surgery?
Indications: Calculi cannot be hydropropulsed
Where: Prescrotal - commonly where the obstruction is, superificial and less cavernous tissue
Alternative: Perineal - use when calculi is lodged between scrotum and ischial arch
Preferred surgery: Cystotomy
What are the closure methods for a prescrotal urethrotomy? Name advantages and disadvantages.
Option 1: Primary closure using 4.0 or 4.0 absorbable monofilament
(+) Can ensure urethra is patent, easier to control hemorrhage
(-) Dehiscense, stricture
Option 2: Second intention
(+) Less risk of stricture
(-) Higher risk of hemorrhage, requires longer hospitalization
Why is a perineal approach for uretheral surgery in dogs less preferred than prescrotal?
More difficult -urethra is deeper
Increased risk of infection
What is a urethrostomy?
Forming a permanent opening of the urethra at a new site
What are the preferred locations for a urethrostomy in a dog? Cat?
Dog: Scrotal (other options= Prescrotal, antepubic, perineal)
Cat: Perineal (other=antepubic)
In a scrotal urethrostomy what structures should be draped in your surgical field? How long should the urethral incision be? What is the most appropriate suturing method? What are the complications?
Drape the penis and scrotum
Incision 2.5-4 cm (5-8 x urethral diameter), the caudal extent is where the urethra turns dorsally toward the ischial arch
Suture urethra to skin using 4.0 or 5.0 absorbable or non-absorbable monofilament
When closing must accurately appose the skin and mucosa
Only engage urethral tissue, AVOID CAVERNOUS tissue
Complications (_occur when technique is poor, SQ tissye is exposed or wrong suture used)_: Hemorrhage, dehiscence, urine scald, stricture, UTI
What is a disadvantage of a canine prescrotal urethrostomy?
Higher incidence of urine scald
What are the indications for a perineal urethrostomy in a cat? What are the goals of the procedure?
Indications: Frequent obstructions, strictures, trauma
Goals: Salvage procedure to treat FLUTDS and calculi - adequate mobilization of urethral mucosa (complications occur if not), preserve urethral branches of Internal Pudendal nerve with minimal dorsal dissection, create a wide urethral orifice to decrease the incidence of obstruction
When performing perineal urethrostomy in a cat, what ligament must you sever? Which muscles must you transect and which must you excise? To which structure do you dissect to?
Ventral penile ligment
Ischiocavernosus & Ischiourethralis muscles (from insertion on ischium)
Retractor penis muscle (dorsally)
Dissect to bulbourethral gland
How do you check whether the urethral orifice is wide enough when performing a perineal urethrostomy in a cat? What are the complications of this surgery?
By inserting a mosquito hemostat to the hinge
Complications: Hemorrhage (inevitable, resolves over time), UTI (anatomical alterations of defense mechanism), Stricture (due to technique, a revision procedure or antepubic procedure), SQ urine (urethral tear or improper suturing, must catheterize for 5-7 days), Perineal hernia, Urinary incontinence (rare, due to dorsal dissection of pudendal Ns)
When is a antepubic urethrostomy indicated and what are the complications?
Creation of a urethrostomy on the ventral body wall cranial to the pubis
_Indications:_Recurrent pelvic urethral obstructions, failed perineal urethrostomy that cannot be revised
Complications: Urine scald, (ascending) UTI, incontinence
What are the 2 most common complications of urethral wound repair? How are they avoided?
Stricture: avoid using indwelling catheters esp. those that distend the urethra, if stoma is made too small, avoid urine leakage (causes granulation tissue formation), inedequate mobilization of urethra can be treated by dissecting the penile remnant from surrounding tissue and properly mobilizing it
Urine leakage: ensure proper aposition of layers when closing, choose appropriate suture and closure patterns,
