SA neutering, urinary Flashcards
What neoplasia are a higher risk with neutering?
Osteosarcomas in Rottweilers (esp if spayed <1y)
Haemangiosarcoma and MCT in Viszlas (spayed any age)
TCC and cardiac tumours in spayed animals
What age to neuter animals?
Kittens from 4 months (pre-pubertal) - but GA risk with maturity of liver and kidneys, hypothermia risk (small glycogen reserves) etc
Puppies:
- benefits of prior to first season = reduced mamary neoplasia risk, uterine/ovarian vessels small, reduced inconvenience to owner
- disadvantages of prior to first season = anaesthetic considerations
- contraindications to prior to first season = juvenile vaginitis, juvenile urethral sphincter mechanism incompetence
- if after first season, always in anoestrus (>12 weeks after oestrus), >6-8 weeks postpartum (preferably >3 weeks post weaning)
- can do combined with caesarean
Medical options for neutering?
GnRH agonists
GnRH vaccine, antagonists - implant, injection
Pros and cons of surgical neutering?
Pros:
- permanent
- perioperative pain
- 100% effective
- eliminates neoplasia of repro tract
Cons:
- more expensive
- GA
Pros and cons of medical neutering?
Pros:
- quick
- cheaper in short run
- no anaesthetic
Cons:
- temporary
- pain on injection
- never 100% effective
- repro tract neoplasia still possible
- unknown effect on USMI etc
When not to neuter based on clinical exam?
Lactation False pregnancy (can make it permanent) In heat (uterus more engorged and friable) Skin pyoderma (post-op infection)
Open technique for dog castration?
Incise vaginal tunic and pop out testicle
Divide testicle and tunic - use clamp
Ligate vas deference and blood vessels individually, then together
Haemostat distal to ligatures, then divide
Check for haemorrhage
Close vaginal tunics, s/c tissue, skin
Closed castration technique for dog castration?
Keep testicle within tunic, ease out of incision
Place one encircling and one transfixing ligature around the entire spermatic cord and tunics
Haemostat distal to ligatures, then divide
Check for haemorrhage
Close vaginal tunics, s/c tissue and skin
Complications of dog castrations? How to avoid?
Urethra - vulnerable at first cut and when closing (make sure to push testicle forward)
Scrotum - dermatitis (care with clipping and scrubbing)
Scrotum - haematoma (care with haemostats)
Cryptorchids - Why are they a problem? How to find them? Where are they?
Vulnerable to torsion, higher risk of neoplasia (13.6x greater risk of seminoma or SCT), may or may not be functional
Often small/soft/misshapen
Palpation, US, exploratory laparotomy
Inguinal - may be able to ease down to normal incision or if not do separate inguinal incision
Abdominal - can be anywhere, exploratory laparotomy, follow ductus deferens
Bilateral castration recommended (sex linked autosomal recessive trait)
Keep the testicle!!
Bitch spay - How big an incision? How to locate ovaries? How to exteriorise the ovaries?
Incise from umbilicus to last pair of nipples (larger if deep chested, obese or large breed
Locate ovary by duodenal (right) and colonic (left) manoeuvres
Exteriorise ovary - stretch (pull ovary caudally, break with other hand) or cut suspensory ligament
How to ligate the ovarian pedicle?
3 clamp technique At least 2 ligatures Encircling and transfixing Or two encircling Or encircling and Miller's Ligate broad ligament as appropriate - ranges from barely existent to full of fat and blood vessels (make a window in an area without vessels)
How to ligate the cervix?
Traction everything cranially
Transfixing and encircling ligatures
Clamp and cut cranial to ligatures
Check for bleeding
How much blood is too much blood?
Check gutters and cervix Check broad ligament Use suction or swab to see Wait Muscle ooze?
Ovariectomy - Benefits?
Quicker Pyometra unlikely (exogenous progestins required) But no difference in pain score, surgical time, haemorrhage, short or long term complications
Bitch spay closure?
Simple continuous for muscle - less suture material, quicker, weakest point is knot
Skin - intradermal or cruciate/interrupted or staples
Flank cat spay technique?
Retriece uterus with finger or spay hook
Find an ovary on one end and bifurcation on other
Ligate pedicle - single ligature often fine
Traction on uterus to find other horn
Care clamping uterus - may tear, ligate caudal to tear
What drugs to use for neutering?
Antibiotics not indicated
Analgesia:
- LA - lidocaine (pedicles, midline, testicles, incision)
- full mu agonist in premed e.g. methadone
- NSAID if not contraindicated (renal/GI disease, receiving steroids)
- consider paracetamol
- 3-5d home pain relief
Comfortable animals don’t chew wounds or cry and settle at home = happy owner
Post op care for neutering?
Pain relief
Exercise - midline require strict rest policy, lead only walks for one month, avoid stairs, jumping, climbing
Owner to monitor wound for swelling, redness, discharge, pain
Deeding - reduced exercise so need less calories, reduced metabolism, so reduce ration by 20% when not exercising
What must all closing sutures of a bitch spay involve?
All bites must have strength holding layer = fascia of rectus abdominus
What late post op neutering complications are there?
Ovarian remnant: - signs of in heat - more common on right side - more common in dogs - check ovary in surgery to ensure completely excised Stump pyometra: - only if progestogen exposure and remaining uterine tissue Granulomas: - use of non absorbable suture material - poor tissue handling and aseptic technique - excessive devitalised tissue left Urethral sphincter mechanism incompetence: - multifactorial - exclude other causes (especially UTI) - 90% respond to phenylpropanolamine - second line ephedrine or estriol - surgical options
What innervation controls filling and emptying of the bladder?
Filling and storage
- mostly sympathetic via hypogastric nerve
- B receptors in detrusor muscle for relaxation
- A receptors in urethral smooth muscle and trigone for contraction
- also somatic via pudendal nerve - urethral striated muscle contraction and inhibition of detrusor reflex
Emptying:
- mostly parasympathetic via pelvic nerve
- stimulates stretch receptors in bladder wall
- contraction of detrusor muscle
- relaxation of urethral muscle
- = detrusor reflex
What allows urinary continence?
Brainstem micturition centre integrates urethral and detrusor function
Cerebral cortex gives voluntary control by over-riding the detrusor reflex
How to investigate urinary incontinence?
Detailed history - e.g. bed wetting, dribbling urine, constant or when excited etc, thirst (could just be PUPD)
Clinical exam (if puppy dripping urine every min etc likely ectopic ureter)
Biochemistry and haematology (check for UTIs etc)
FeLV test in cats
Urinalysis
Urine culture and sensitivity
Observe patient urinating
Plain abdominal radiographs - screen for calculi etc
IV urogram/CT angiography - to check for ectopic ureters
Retrograde (vagino) urethrogram
US exam of urinary tract
Urethroscopy/cytoscopy