116.Bladder

Question 1

ligaments and layers of the bladder

Answer 1

LIGAMENTS—ventral median ligament (urachus remnant)–lateral ligaments (fat, distal ureter, umbilical artery)LAYERS—transitional epith cell mucosa (mucosa and submucosa make up urothelium)–submucosa—smooth muscle detrusor m–serosaNO ANATOMICAL INTERNAL URETHERAL SPHINCTER—just blending of detrusor with smooth muscle of urethra

Question 2

innervation to bladder and micturition reflex

Answer 2

SNS (storage)—hypogaStric (in TL cord)alpha–neck and proximal urethra (active–contract)beta–detrusor muscle (inhibit—relax)—when bladder fills, stretch receptors on muscle activate to stimulate PSNSPSNS (Peeing)–Pelvic (sacral and pontine micturition center)inhibit beta—causes detrustor muscle to contractinhibit alpha–causes bladder neck and prox urethra to relaxinhibit somatic pudendal nerve Somatic (voluntary)–Pudendal nerve (sacral)acts on striated urethral musculature (external urethral sphincter) to contract for urine retention and relax for voluntary micturitionall innervation to bladder merges together at the pelvic plexus on the dorsal surface of the bladder

Question 3

blood supply to the bladder

Answer 3

internal iliac–> umbilical artery–> cranial vesicular arteryinternal iliac–>internal pudendal—> vaginal–>middle rectal, uterine, urethral, caudal vesicular artery internal iliac–>internal pudendal–>prostatic–>middle rectal, ductus deferens branch, urethral, caudal vesicular artery

Question 4

tissue strength regained during wound healing

Answer 4

mucosal defects fill in 5 days100% strength in 14-21 days

Question 5

reported rate of suture associated cystoliths

Answer 5

10% dogs 4% catsunknown suture material usedrecommend monofilament absorbable, taper pointsubmucosal holding layer

Question 6

suture recommendations in canine sterile urine or urine inoculated with E.coli vs Proteus

Answer 6

polydiaxanone and polyglyconate are acceptable for canine urine (sterile or w Ecoli) but poliglecaperone may NOT have sufficient tensile strength ALL the tested sutures dissolved before day 7 in Proteus infected urine

Question 7

treatment for hyperkalemia in urinary patients before anesthesia

Answer 7

–fluid diuresis (NaCl) but may need to supplement K in post obstructive diuresis period, monitor–relieve obstruction (cysto, catheter)–temporary urine diversion—calcium gluconate if brady cardia–insulin, dextrose, NaBicarb therapy

Question 8

diagnostics for bladder

Answer 8

—PE, RECTAL—CBC, Chem, UA—cystocentesis (blind or US guided)—abdominal rads—positive or double contrast cystourethrograms (rads or fluoro)–needed to ID intraperitoneal rupture–IV excretory urogram if urine leakage is retroperitoneal–abdominal US (SN for stones and wall lesions)–Catheter biopsy–cystoscopy +/- interventional techniques (bx, culture, stone retrieval, polyp removal)—laparoscopic assisted cystoscopy/cystotomy

Question 9

diseases of the bladder

Answer 9

—neoplasia–urolithiasis–bladder diverticula–polypoid cystitis–idiopathic renal hematuria–ectopic ureters–cystitis/urethritis–urethral strictures–trauma/rupture

Question 10

indications for cystotomy

Answer 10

—bladder mass resection–repair ectopic ureters–stone retrieval–biopsy culture for severe cystitis–investigate idiopathic renal hematuria—repair bladder traumaalways consider biopsy and culture of MUCOSA!

Question 11

T/Fthere is no difference in the likelihood of urine leakage, adhesions, or calculi formation btwn dorsal and ventral cystotomy approaches

Answer 11

trueventral is easier and decr risk of iatrogenic damage to ureters

Question 12

indications for cystectomy

Answer 12

–bladder neoplasia–necrotic wall from trauma–bladder diverticula–patent urachus* if a lot of bladder is removed, may need temporary urine diversion; if removal of tissue near ureters, may need to reimplant

Question 13

bladder regeneration after cystectomy

Answer 13

–mucosal regeneration–synthesis–remodeling of scar–hypertrophy and proliferation of smooth muscle–distension of remaining bladder wallTRIGONE is key for bladder regeneration bc the regeneration cells arise from the epithelium of the terminal ureters and urethracan excise a lot–even 75% if trigone intact—biggest complication may be pollakuria, none were incontinent

Question 14

what to do if cystectomy is expected to exceed the ability to close the bladder wall safely

Answer 14

–seromuscular colonic augmentation (exterior wall of colon became cranial wall of bladder)–ileocystoplasty–rectus abdominus muscle flap—SIS in 40% cystectomy model (not 90%)consider temporary urinary diversion

Question 15

indications for cystostomy tube

Answer 15

TEMPORARY–diversion of urine due to extensive cystectomy—diversion of urine due to trauma (with or without repair)—relieve obstructionPERMANENT–palliative for neoplasia obstruction–bladder atony (neurogenic)Use: Mushroom Tip (dePezzer) or low profile gastrostomy tubes (silicone)must keep in for 7 days to allow stoma to heal

Question 16

complications associated with tube cystostomy

Answer 16

50%–inadvertant tube removal–kinking/obstruction–animal mutilation–tube breakage–stoma inflammation, infection–UTI (biofilm, residual urine)–uroabdomen–urine leakage at stoma

Question 17

methods of cystopexy

Answer 17

–tube cystopexy–incisional cystopexy–lap assisted cystopexyseromuscular and submucosal layers of bladder to the transversus abdominus

Question 18

the most common site of urinary tract rupture following trauma

Answer 18

BLADDER100 dogs with trauma with pelvic fractures—16 had urinary tract rupture

Question 19

diagnosing uroabdomen on abdominocentesis

Answer 19

–cytology (look for bacT)–creatinine in fluid > 2.4 x serum–K in fluid > 1.4 x serum

Question 20

dose for perionteal dialysis

Answer 20

20 ml/kg

Question 21

majority of canine and feline uroliths

Answer 21

—struvite (magnesium ammonium phosphate)–forms in alkaline, associated with UTI, small female dogsrecur 21%–calcium oxalate–forms in acidic to neutral pH, male cats and dogs, very radio opaque, causes hyperCa, metabolic acidosis, acidifying diets (those used to treat struvite stones)usually STERILE in cats

Question 22

percentage of idiopathic hyperCa patients that also have calcium oxalate urolithiassis

Answer 22

35%

Question 23

methods for retrieval of calculi from the bladder

Answer 23

–cystotomy–cystoscopy (transurethral)–laparoscopic assisted cystotomy—voiding urohydropropulsion–catheter assisted retrieval–lithotripsy (Ho: YAG)–female dogs best candidate

Question 24

reported incomplete removal Grant et al JAVMA 2010

Answer 24

20% incomplete removaldogs with both urethroliths and urocystoliths were more likely to have failed cystotomy

Question 25

location preference for polypoid cystitis vs neoplasia in the bladder

Answer 25

neoplasia—trigone polypoid cystitis—cranioventral

Question 26

malignant tumors of the bladder

Answer 26

bladder is most common location of canine urogenital tract neoplasia—TCCbladder is the SECOND most common location of FELINE urogenital tract neoplasia—RENAL LSA (is #1)both very malignant, staging important

Question 27

therapy recommendations for TCC

Answer 27

–total cystectomy or wide partial cystectomy –associated with high morbidity and never curative alone (histolopathological tumor free margins are unlikely)–palliative cystostomy tubes–palliative urethral stunting if obstructed–chemo (mitoxantrone) plus piroxicam 300 days with 180 days with NSAID alone–radiation therapy has no role, poor local tumor control and serious side effects

Question 28

if you had to list methods for surgical treatment of TCC

Answer 28

–partial cystectomy and primary closure–partial cystectomy with rectus abdominus, SIS, ileocystoplasty, or seromuscular colonic augmentation–total cystectomy with ureterouterine diversion–total cystectomy with ureterocolonic diversion–tube cystostomy (palliative)surgery alone is never curative and histopathological tumor free margins are unlikely; hi morbidity