Surgery of the urinary tract – kidneys and bladder Flashcards
(39 cards)
What are the main principles of urogenital surgery?
- Apply Halsted principles
- Gentle tissue handling
- Suture material: monofilament absorbable
Describe the anatomy of the kidneys
- Paired, bean-shaped retroperitoneal organs
- R more cranial than the L
- L more mobile than R; both more mobile in cats
What is the normal length of the kidneys in cats and dogs?
Renal size measured on VD abdominal radiographs
Cat: 2-2.5 x L2 length
Dog: 2.5-3.5 x L2 length
Name some developmental abnormalities of the kidney
- Renal agenesis (kidney and ureter not present)
- Renal dysplasia (disorganised parenchyma)
- Renal ectopia: should be functioning normally, just not in the right place
- Polycystic kidney disease (Persians, Bull terriers) *cysts can also be acquired
What are the indications for a renal biopsy?
- Renal mass (commonest indication)
- Haematuria of upper urinary tract origin
- Renal cortical disease / Protein-losing glomerulopathy
- Renal failure where underlying cause cannot be determined
• Be aware that if the kidney is already diseased, a biopsy may cause further damage
Renal biopsy should be performed after which other diagnostics?
- Haematology
- Serum biochemistry
- Urinalysis/urine bacteriology
- Diagnostic Imaging
- Coagulation profile: clotting factors, platelet numbers, etc
What are some contraindications for renal biopsy?
- Anaemia / Coagulopathy
- Oliguria / Anuria / Severe azotaemia
- Hypertension
- Urinary obstruction
- Hydronephrosis, cysts
- (Peri)renal abscess, pyelonephritis
- Solitary functioning kidney
What potential complications can occur with a renal biopsy?
- Haemorrhage (most common)
- Haematuria
- Hydronephrosis (obstruction by blood clots)
- Renal infarction
- Damage to renal vasculature
- AV fistula
- Infection
- Cyst or haematoma formation
- Renal fibrosis
What are the methods for renal biopsy?
- Fine Needle Aspirate (FNA): collects cells
- Tru-cut or Spring-loaded Biopsy instrument 14-18G: Collects tissue
- Surgical
What are the different approaches to the kidney?
- Percutaneous (blind) biopsy (not recommended)
- Ultrasound-guided biopsy
- Keyhole biopsy: flank approach
- Laparoscopic biopsy: requires specific training and equipment
- Ventral midline celiotomy: most common way
Where should the needle advance in the kidney when taking a biopsy?
Across the cortex only! not towards the hilus
During surgical approach which structures are moved to expose the kidney?
Retraction of the duodenum and descending colon towards the midline exposes the kidney
What is a nephrotomy used for?
- Used to obtain a Wedge biopsy
- Used in removal of nephroliths (nephrolithotomy)
Describe nephroliths and their clinical signs
- May be incidental finding
- Calculi occur more commonly in bladder than kidneys
- Clinical signs: lumbar/abdominal pain, haematuria, recurrent UTI, azotaemia
How are nephroliths treated?
- Medical management
- Calcium oxalate do not respond to medical management so have to be surgically removed
- Surgical management: consider referral
What is a ureternephrectomy?
Removal of the kidney and associated ureters
What are the indications for a ureternephrectomy?
- Trauma
- Hydronephrosis (ligated ureter?!)
- Renomegaly/renal masses
- Management of single ureteral ectopia?
- Harvest kidney for transplantation
What must a patient have to undergo a ureternephrectomy?
Functioning other kidney
What is the most common renal neoplasia in cats?
Lymphoma
What is the most common renal neoplasia in dogs?
Renal cell carcinoma
Describe the history and clinical signs of an animal with renal neoplasia
- Slow onset (weeks-months)
- Haematuria
- Weight loss
- Depression/lethargy
- Inappetence
- Pyrexia
- Lameness
- Abdominal distention
How is renal neoplasia investigated/diagnosed?
- Abdominal palpation
- Haematology and serum biochemistry
- Radiography
- Computed tomography
- Abdominal ultrasound
- Biopsy (FNA, Trucut, excisional)
- CHECK FOR METASTASIS
How is renal neoplasia treated?
- Lymphoma: chemotherapy, not surgical disease
- Unilateral renal neoplasia with no gross metastasis: Ureteronephrectomy
- Surgery can be challenging due to neovascularization
- Surgery is palliative until metastases become apparent
Describe two congenital abnormalities of the bladder
- Patent urachus: fetal communication between bladder and allantoic sac persists
- Vesicourachal diverticulum: external opening of urachus closes but blind-ending diverticulum remains open
