Equine Castration Flashcards
Double peritoneal fold around testis and SC is called?
Tunica vaginalis
What links parietal tunic onto epididymis ?
Ligament of tail of the epididymis
Spermatic Cord =
Tunica vaginalis, BVs, nerves and lymphatics
Patient Selection for Castrate?
- Age: traditionally spring of yearling year
- Can be done before weaned; consideration if older
- Handling/temp
- Palpation -> two testes? scrotal/inguinal hernia?
- Tetanus vaccination (ideally first 2)
Describe open castration -
- Parietal tunic incised to expose testis, epididymis and cord structure before emasculating
- No ligatures skin is left open to heal by 2nd intention
Describe closed castration
Parietal tunic is not incised - Portion of tunic surrounding testis and distal sperm cord is removed
- Ligatures used. Skin may be sutured close
Describe Semi-closed castrate?
- Parietal tunic opened to allow for inspection inside parietal tunic
- Ligatures used. Skin close as for closed castrate. Tunic can also be closed
Advantage of Open?
: Simple, quick, excellent drainage, can
be done in standing sedated horse (so
cheapest). Best option when incomplete
sterility.
Disadvantage of Open Castrate?
Higher risk of some complications
(haemorrhage, infection, eventration)
Closed - Advantages?
: Reduced incidence of haemorrhage,
infection and eventration. May be more
suitable for older horses, donkeys, mules
and draft breeds (extra haemostasis
provided by ligatures).
Closed - Disadvantages?
Ideally performed in sterile
environment. Requires general
anaesthesia (cost, anaesthetic
complications). Ligatures can act as a
focus for infection. Poor drainage. Unable
to visually check inside parietal tunic
Adv - SEMI open?
: As for closed castration, plus visual
check inside tunic, allows more accurate
ligature placement therefore further
reduced risk of haemorrhage.
Disadvantages of Semi-closed?
Requires general anaesthesia
(cost, anaesthetic complications). Slightly
increased surgical complexity
When do we do Standing Sedation?
- Open castrate
- Well handled patients, no tiny ponies or difficult to palpate testes
- Most common approach inUK
Adv of Standing sedation?
Cheapest, no anaesthetic risk, least time -consuming
Disadvantage of Standing Sedation?
Poor surgical conditions, risk of injury to vet
When do we do Field Anaesthesia?
- usually open but can be any
- Good for small ponies or small testes
- Common in UK
Adv of Field Anaesthesia?
Cheap, easier to see/ feel/ access testes
Disadv of Field Anaesthesia?
Basic anaesthesia/ monitoring, risk of injury to personnel during anaesthetic recovery. Clean safe area required to anaesthetise and recover horse
When do we use theatre anaesthesia?
- CLosed or Semi-closed
- Mature stallions (also consider for mules, donkeys, draft breeds)
GOLD STANDARD
Adv of Theatre anaesthesia?
High quality anaesthesia/ monitoring, excellent surgical conditions, minimal danger to personnel
Disadv of Theatre Anaesthesia ?
More expensive
How to use Emasculators?
- crush (haemostasis) and cut
prior to use: - Ensure emasculators open normally
- Ensure ratchet engaged
What are the two types of Emasculators?
Step 1 of Open Castrate
Step 2 open castrate
STEP 3 open castrate ?
STEP 4 OPEN CASTRATE?
STEP 5 OPEN CASTRATE?
Step 1 Closed Castrate?
Step 2 Closed C?
STEP 3 CLOSED C?
STEP 4 CLOSED C?
STEP 5 CLOSED CASTRATE ?
What technique for Semi-closed castration?
What general considerations to think about?
- Facilities/ hygiene?
Time of day
Weather? / shelter
Signed consent
Peri-operativeMEdications?
- IV fluxinin or phenylbutazone
- Oral phenylbutazone for 5 days
- Prophylactic ABs, -> IM procaine penicillin, IV oxytetracycline, oral TMPS?
- Tetanus antitoxin
- Toxoid vaccine booster if not recent vacc
what sedation for standing sedation?
Alpha 2 agonist and butorphanol
What practical things to do for standing castrate?
- Tail bandage, scrotum scrubbed
- Competent handler on same side
- Nose twitch?
- surgeon close to horse’s shoulder
What local anaesthesia can we use?
Lidocaine or Mepivicaine
10-20ml along planned incision sites
5-10ml into each testis
What considerations for Field Anaesthesia?
- Care risk to humans
- Suitabel space
- IV catheter
- Tail bandage, scrotum scrubbed, mouth washed out
What ANAESTHETIC considerations with field anaesthesia?
- Second vet/ nurse to monitor
- Alpha 2 agonist plsu butorphanol pre-med then Ketamine and Diazpam induction
-> ket or sedative top ups
-> local
What positioning for field anaesthesia?
Lateral recumbency wth upper pelvic limb pulled forwards and secured with a rope
What Post op care for open castrate?
- Confinement in clean stable for 24h to allow clots to stabilize
- Thereafter, exercise is vital!
- Paddock turnout best
- Owner should observe the site but should not clean it
Post-op care for closed or semi-closed castrate?
- Confinement in clean stable for several days
- Gradual return to exercise over the next ~week
- Owner should observe the site but should not clean it
What is Cryptorchidism colloquially known as?
‘Rigs’
Describe cryptorchidism in horses
- Retention of one common
- Complete retention of both is rare
- Can be complete abdominal, partial abdominal, inguinal or completely absent
How do we diagnose Cryptorchidism ?
- Sedation & deep palpation into inguinal ring
- US (transabdo & transrectal)
- Serum AMH
(Oestrone sulphate)
-> if equivoal AMH -> dynamic testing (hcG stim test)
What surgery can we do for cryptorchidism?
- Para-inguinal
- Inguinal
- Laparoscopic
What are common Castration complications?
- Haemorrhage
- Swelling, Oedema, Seroma formation
- Infection
- Evisceration of omentum or intestine
- Septic funiculitis
- Iatrogenic penile trauma
- Hydrocele (Vaginocele)
- Peritonitis, colic
- Lameness
- Incomplete castration (‘rig’)
- Continued masculine behaviour (‘false rig’)
Describe NORMAL haemorrhage in open castrations?
- Drip blood (slowly) for several hours -> should be able to count the drips
What source of bleeding ?
Testicular artery
What risk factors to haemorrhage?
- Improper application of emasculators
- Catching scrotal skin
- Nuts not tight
- Assemble incorrectly
- hick cords: rq double ligation
How do we assess blood loss?
- demeanor
- HR/ pulse
- MM/CRT
- Subjective quantitiy assessment
- Haematology parameters (PCV less than 20% -> acute)
What is the blood volume of a horse?
9% of Bodyweight -> 45L for 500kg horse
How do we prevent haemorrhage?
- Keep hold of spermatic cord until assessed haemorrhage -> aliss tissue forceps
- Large horses, older horses, donkeys & mules: castrate closed or semi-closed under anaesthesia with ligatures
What TX for haemorrhage ?
- Don’t panic – give time!
- Try clamping a vessel
- Mixter right angled forceps
- Pack with unrolled bandage
- Anaesthetise and clamp/ligate artery
- Referral if possible
Describe Swelling/ oedema
- ‘Some’ is normal
- ‘Too much’ swelling and/or oedema is relatively common
- Can occur with or without seroma formation and/or infection
How to prevent a seroma in open castrate?
exercise following open castrate & big surgical incision
How to prevent seroma in closed ?
- reduce dead space
- Goof surgic&l technique
- rest and slow return to exercise post surgery
How to manage open castrate seroma?
- Re-open wounds with sterile gloved finger and re-establish drainage
- Consider AMs if suspect infection
How to manage seroma in closed castrate?
- Do not open wound if not believed to be infected
- Focus on reducing risk of secondary infection
- Antimicrobials?
- Wound care
Describe scrotal infection
- COmmon with open castrate
- Often minor, but check for: fever, dull demeanour, inappetance
Is infection less common in closed?
YES but potentially worse bc -> lack of drainage & presence fo Implant
Tx for Scrotal infection?
- Swab and submit for culture and sensitivity
- Clean with antiseptic
- Re-open wounds with a sterile gloved finger as per seroma
- Sytemic antimicrobials and anti-inflammatories
IF protruding skin, fascia or blood clot .. worried?
NO
What can eviscerate?
Omentum > via inguinal hernia - not emergency
Tx for clots/skin/fascia/ omentum ?
- High degree fo sterility
- Pull out as far as poss
- Emasculate
- Monitor closely
Describe evisceration of SI ?
- Via inguinal hernia
- Rare but very serious
- Likely fatal
Draft & standardbreds predisposed ?
Tx for evisceration of intestines ?
- Initial aim: protect bowel from further damage and contamination
and get ready for transportation - Protective sling and urgent transport to clinic with surgical facilities
- Possibly indicated: Field anaesthetic, lavage, place back in scrotum
and suture skin prior to transportation
What is Septic Funiculitis?
‘Scirrhous cord’ -> chronic non healign inflammation that keeps recurring and forms a discharging sinus tract
uncommon
Cause & prevention of septic funiculitis?
- Underlying cause? “absorbable” suture can be a focus of infection
- Prevention: avoid use of ligatures in non-sterile surgery if possible
Initial management of Septic funiculitis?
- Culture and sensitivity
- First line: antimicrobials
- Recurrent failure of appropriate antimicrobials is diagnostic
Ultimately: - Bold surgical excision of thickened avascular and necrotic tissue
Describe iatrogenic penile trama
- Root of penis mistaken for testis > emasculation of root of penis
- More a problem with closed castration, inexperienced surgeons
- Treatment: Emergency referral for repair or phallectomy
describe Incomplete Castratio
- Drawback of closed castration: can’t see what you’re emasculating
- Young colt foals can have relatively large gubernaculum – can be
mistaken for testis - Partial abdominal cryptorchids – tail of the epididymis can lie in the
inguinal region and may be mistaken for a small inguinal testis
Prevention for incomplete castration?
- Check the testes – before emasculating (by using semi-closed or open
technique) and afterwards (always, regardless of technique used) - Cryptorchid castration: open the vaginal process to visual contents and
ensure the presence of an epididymis prior to castrating
Describe peritonitis?
- Rare complication
- Abdominal pain/colic signs
- Pyrexia
- Very dull
- Weight loss
- Diagnosis: abdominocentesis
- Referral for intensive care
- IVFT, supportive care, injectable antibiotics, anti-inflammatories, +/-
peritoneal lavage
