Surgical Disorders of the Urinary Tract & Umbilicus Flashcards
How is endoscopy used to examine the urinary tract?
- Evaluation of urine outflow from ureters - Every 20-45 seconds under xylazine sedation
- Catheterisation of ureters - Confirm unilateral / bilateral renal/ureteral disease
How is ultrasound used to examine the urinary tract?
- Transrectal: Bladder in adults
- Transcutaneous: Kidneys, Bladder, Umbilicus
- Guided needle biopsy of kidney(s)
When might a nephrectomy be indicated in horses?
Renal neoplasia
Pyelonephritis non-responsive to medical treatment
A ruptured bladder is most commonly seen in which horses?
Foals 1-5do
Why does a ruptured bladder occur in foals?
More common in colts
Usually occur during parturition but clinical signs take time to develop
Uncommon in adult horses but can occur
What are the clinical signs of a ruptured bladder in foals?
- Depression / off suck
- Progressive abdominal distension
- Mild / moderate colic
- Increased frequency of urination and small urination volume, or no urination
What signs of a ruptured bladder are seen in haematology and bichemistry?
- Hyperkalaemia
- Low sodium and chloride
- Dehydration
- Metabolic acidosis
How else can a ruptured bladder be diagnosed?
Peritoneal fluid analysis
Ultrasonography
Radiography & contrast studies
How does the result of a peritoneal fluid analysis confirm a ruptured bladder?
Peritoneal creatinine more than double serum creatinine
Before treating a ruptured bladder what must be done?
Stabilisation prior to GA as hyperkalaemia can cause fatal arrythmias
- Abdominal drainage of urine (slow) – reduce K+ but also improves ventilation
- Rule out concurrent disorders e.g. sepsis
- Antibiotics
- Check IgG status
How are foals stabilised to reduce the hyperkalaemia?
i.v. saline / Hartmann’s solution
+/- sodium bicarbonate
Calcium borogluconate
Insulin / glucose
How is bladder rupture in foals treated?
Surgical repair via midline laparotomy with resection of umbilicus and urachus
Are uroliths more common in male or female horses?
Males (more common) - can block ureter
Females - remain in bladder and cause mild haemorrhage during urination
Describe the two types of calcium carbonate uroliths seen in horses
Type I (more common) – spiculated, yellow/green
Type II – smooth & white
Describe the history and presenting signs of urolithiasis
Haematuria
Stranguria
+/- pollakiuria, pyuria or incontinence
How is urolithiasis diagnosed?
Rectal examination
External palpation
Ultrasonography
Endoscopy
How is urolithiasis in horses treated?
- Surgical removal
- Laparotomy
- Laparoscopy
- (Incision directly over urolith if in urethra) - Electrohydraulic / laser lithotripsy
- If the horse cannot urinate due to a distal urethral obstruction, a temporary perineal urethrotomy may be needed
What is sabulous cystitis?
Secondary problem, consequent to bladder paralysis or other physical or neurologic disorders interfering with complete bladder emptying
What is the cause of bladder eversion?
Due to excessive straining
Parturition or foaling
The umbilicus is composed of?
One vein and two arteries
Describe what normally happens to the umbilicus after parturition
- Umbilical cord breaks naturally immediately after parturition
- Iodine / chlorhexidine should be applied immediately to the umbilical stump
- Should progressively dry up & disappear over 4-6 weeks
- Investigate if moistness >24h, swelling / pain on palpation or if the foal is febrile
What is a patent urachus?
Urachus fails to close spontaneously or can reopen if sepsis occurs
Moisture around umbilicus +/- dripping of urine
How should a patent urachus be treated?
- Check for concurrent septicaemia/septic arthritis/ physitis
- Assess IgG status
- Medical: Antibiotics, Topical agents (concentrated phenol or 7% iodine solution or with silver nitrate applicators)
- Often self-resolving
- Surgical (if needed) Resection of the urachus
When is umbilical sepsis seen?
First 1-2 weeks of life but can occur later
Foal depressed & off suck
Swollen, painful umbilicus
How is umbilical sepsis diagnosed and treated?
- Ultrasonography of the umbilicus reveals enlargement of structures
- Assess IgG status & assess for concurrent septicaemia / septic arthritis / physitis
- Blood culture, haematology & biochemistry
- Systemic antibiotics
- Surgical resection if no response to therapy / deterioration
How are umbilical hernias assessed?
Most are small & will resolve with time
Determine size & whether reducible / non reducible
If an umbilical hernia is non-reducible what should be done?
- If defect is non-reducible, immediate surgery is needed
- Owner must evaluate daily
- Can cause strangulation of bowel if entrapped
When is surgical repair of an umbilical hernia indicated?
- Large defect (>3-5cm)
- Defects persists more that 6 months
- Defect enlarges
- Associated with colic