URINARY SYSTEM: 114, 115, 116, 117, 118, 119 Flashcards
does renal capsular arteries arise from renal arteries?
no, they arise from phrenicoabdominal arttery or adrenal artery. usually are more prominent in deseased kidney
decsribe the 3 phases of renal contrast excretion
1) renal angiographic phase: almost immediately, demonstrates arterial supply
2) renal phase: also known as renal blush, contrast through renal parenchima
3) excretory phase: contrast flows into collecting tubes
policystic kidney signalment and incidence
persian cats and persian cat similar (himalayans, exotic shorthairs). prevalence extimated to 37-38%
most common composition for feline kidney calculi
calcium oxalate
renal cystadenocarcinoma is associated with what type of dermatological disorder?
nodular dermatofibrosis in german sheperd. is a inherited neoplastic syndrome
kidney tumor and related survival expectancy
carcinoma - 16 M
sarcoma- 9 M
nephroblastoma - 6 M
hemangiosarcoma - 278 Days
difference beetween renal cysts and perirenal pseudocysts
renal cysts are epithelial-lined
pseudocysts lacks an epithelial lining
idiopathic renal hematuria: signalment and treatement
often large breeds <2 years.
treatement:
-renal pelvic infusion of povidone-iodine or silver nitrate, followed by ureteral stent placement
-ureteronephrectomy
-renal artery embolization
-ureteroscopic electrocauterization
does nephrotomy influence renal function?
inconsistent findings! older studies reported decrease to 40-50% of glomerular function after partial nephrectomy. recent studies reported an increase in GFR.
name 2 different nephrotomy techniques
1) bisectional nephrotomy: sharp incision
2) intersegmental nephrotomy: blunt dissection with a periosteal elevator, scalpel blade handle or similar
luminal ureters diameter feline vs canine
CAT: 0,4 mm
DOG: 2-2,5 mm in dogs 20-30 kg
anatomic curiosities of ureters
right ureters can be circumcaval in up to 30% of cats. left ureters have a particular bend 3 cm distal to it’s course. usually it is a common site for obstruction
microscopic anatomy of the ureters
A) tunaca adventitia
B) tunaca muscolaris
-ext longitudinal
-middle circular
-int longitudinal
C) tunaca mucosa
name some drugs that can determine ureteral relaxation
calcium channel blockers, glucagone, amitriptyline (tricyclic antidepressant)
what are the 4 most important presurgical considerations before ureteral surgery?
1) every cat has a different amount of damage to the obstructed kidney
2) most of the cats undergoing kidneys biopsies have some degree of chronic interstitial nephritis
3) if a cat is azotemic with a unilateral obstruction it must have bilateral CKD
4) overal complication rate of more or less 30%, with mortality to 18-20%
most common causes of ureteral strictures in cats
concurrent nephroureterolithiasis or previous ureteral surgery
what is a urinoma?
it is a retroperitoneal collection of urine
male dogs ureteral ectopia prevalence
15%
ureteroceles embryionic development
failure of regression of the chwalla membrane (divide ureteral orifice from common excretory duct)
how many ligaments does the bladder have?
two lateral ligaments: contain fat and umbilical artery!
one ventral ligament attached to linea alba
sympathetic and parasimpathetic innervation of the bladder
S: hypogastric nerve
- relaxation of detrusor muscle
-contraction of smooth muscle in
bladder neck and proximal urethra
P: pelvic nerve
-somatic innervation to periurethral
striated muscle (muscle contraction)
- detrusor muscle contraction for
bladder empyting
bladder blood supply
enters dorsal
caudal vescical artery: from vaginal or prostatic artery (branch of internal pudendal)
cranial vescical artery: terminal ending of umbilical artery: patent in adult dogs
struvite urolith differences beetween dogs and cats
in dogs 90% of the cases have a UTI (urease producing bacteria so alkalinization of pH)
in cats usually are sterile
biggest portion of bladder that can be excised in human
75%. within 3 months regain a capacity of 300 ml
possible complication of ureters diversion in colon
1) hyperammoniemia secondary to ammonium reabsorption in colon. this induces an hypercloremic metabolic acidosis and encephalopaty
2) pyelonefritis
3) severe colic ulcerations
Urea, creatinine and potassium role in uroabdomen diagnosis
Urea: equilibrates across peritoneum, so if there is no urea in the peritoneal fluid it is defenetly NOT uroabdomen
cratinine: big molecule so it doesn’t get reabsorbed. if found in the peritoneal liquid in higher concentrations than plasma it is uroabdomen
K: also potassium concentration in uroperitoneum fluid are higher than in plasma
percentage of cats with hidiopatic hypercalcemia that can develop uroliths
35%
recurrence of struvite and CO uroliths in cats and dogs
struvite has been reported to recur in up to 21% of dogs and 2,7% of cats
CO has been reported to recur in up to 50% (in 3 years) for dogs and 7% in cats
ECG abnormalities in patients with Hyperkaliemia
1) spiked T waves
2) depressed R, ST, P
3) prolonged QRS, QT, PR
4) ventricular arrithmias
does calcium gluconate reduce potassium serum levels?
No, it only acts as a myocardial protectant (increases treshold for cardiac myocyte depolarization
common location for urethrotomy
in dogs the most common location is prescrotal
common location for urethrostomy in dogs and cats
dogs: scrotal
cats: perineal
less common locations for urethrostomy in cats and dogs
1) transpelvic urethrostomy (caudal ischial osteotomy) in cats but also dogs: access to pelvic uretra
2) subpubic urethrotomy in cats: access to postprostatic uretra
3) prepubic urethrostomy in dogs and cats: access to preprostatic uretra
surgical approach to perineal urethrostomy in cats
1) incision encircling scrotum and prepuce
2) dissection of penis and identification of ischiocavernosus muscles
3) severing of ventral ligament of the penis and both ischiocavernosus muscles
4) severing of retractor penis muscle
5) incise urethra and begin suturing from the most dorsal aspect
6) cut and ligate the distal penis
name the 2 most important possible complication after urethrostomy
stricture and urine extravasation
in the transpelvic urethrostomy, what muscles must be elevated and dissected trom the pubic symphisis?
gracilis and external obturator muscles
in urethral anastomosis is it suggested to use a urine diversion technique?
yes, urinary diversion (catheher, cystostomy tube or both) does not provide significant difference in wound healing and prevent severe strictures
name the 3 possible surgical treatments for urethral disruption
1) temprary urinary diversion and second healing
2) primary repair
3) permanent urinary diversion via urethrostomy or cystostomy tube
signalment in urethral prolapse
young male brachicephalic dogs, specifically english bulldogs
possible surgical options for urethral prolapse
urethropexy and urethral resection and anastomosis
