Urogenital Equine BRAD Flashcards
Indications and approach for a Ovariectomy?
Indications:
a) Bilateral: Jump mare, behavioural
b) Unilateral: Ovarian tumour: Teratoma, adenoma, adenocarcinoma, cystadenoma
DDX: Ovarian haematoma, transitional ovary
Surgical Approach:
- Colpotomy: Ovaries <10cm diameter
Issues: GIT evisceration, haemorrhage, removal of incorrect structure, septic peritonitis
Entry: Via vagina – dorsolateral application of chain around mesovarium after penetrating mucosa & peritoneum
- Flank: Standing (Mares) or recumbent, 10-15cm or larger using suction to deflate cavities
Issues: Seroma via muscle trauma
Entry: Cr. Tuber coxae via ext.& int. ab oblique - Diagonal Paramedian: <20 cm ovaries, short pedicle, close external rectal sheath
Issues: Seroma, incisional dehiscence, herniation, colic
Methods: Overlapping transfixion sutures on the ovary & remove
What are the complications for a ovariectomy?
- ↑ Colic risk
- Haemorrhage
- Peritonitis
- Dehiscence
- Eventration
- Adhesions
- Myositis (Related to Sx time)
- Neuropathy (Sx t)
What is GTCT?
Granulosa Cell Tumour
Location: Granulosa & Theca cells
Hosts: >6 y/o
CS:
- Anoestrus/stallion-like behaviour
- Nymphomania
- Contralateral ovary is small/inactive
- Bilateral and Mx is rare
Dx:
- US: Multi-cystic enlarged ovary
- Serum Inhibin: 1-2ug/ml (87% dx)
- HCG stim test: Serum testosterone >20pg/ml
Complications:
- Mean time to cycle ~8.5m
- Equivalent fertility
- 75% return to normal oestrus
- 76% live foal
What is an Ovariohysterectomy?
Indications: Chronic pyometra, neoplasia
Method:
- IPPV, Muscle relaxants, Sx assistants, GA/DR (?)
- Isolate & ligate mesovarium & ovarian a. & uterine br. Of ovarian a.
- Isolate & ligate Ovarian a. + uterine br. Of vaginal a. in mesometrium/broad lig.
- 2 Layer close of uterine & oversew stump
Describe what Vaginal/Perineal/Rectal Trauma is?
Due to: Dystocia, foaling, mis-mating
- Can include rectovaginal fistula, perineal lacerations as trauma
Treatment:
- Delayed surgical treatment 4-6 weeks: Healthier GT & fibrosis of Submucosal layer = better suture hold
- Soft faeces 1-2wks prior: ↓ Bulk (Grass, pellets), Soften/↓ tension (Paraffin, Epsom salts)
- Peri-operative: Phenylbutazone, procaine penicillin, tetanus prophylaxis
- Sedation: Detomidine & butorphanol IV
- Epidural: Xylazine & Lignocaine diluted, in for 20 min – last for up to 5hrs, 20-18G 1.5/3inch needle
Hanging drop technique – Once in place negative pressure sucks in (C1-2)
Consequences: Untreated – infertility via persistent endometritis
What is Rectovaginal fistula?
–> Rectovaginal Fistula
Location: Between rectum & Vaginal vault
Treatment:
- Debride via transverse dissection along perineal shelf OR convert to 3rd degree laceration
- Small fistulas heal by 2nd intention, large fistulas often req >1 surgery
- Use Balfour/finochiuetto retractors, long instruments, bent scalpel handle
- Direct 10 closure w/ minimal tension, holding layer = submucosa
- Horizontal mattress in submucosa → Simple interrupted in rectal → Vaginal mucosa
What is Perirenal Lacerations?
–> Perineal Lacerations:
1st Degree
Vestibular mucosa & skin at dorsal vulval commissure Tx: Caslick
2nd Degree
Vestibular mucosa/submucosa/ perineal body mm
Tx: Caslick & Perineal body reconstruction
3rd Degree
Communication btwn vestibule, perineal body & rectum Hosts: Maiden mares
Tx: Goetz technique (Single stage) or Aanes technique (2 stage) repair
Treatment:
1. Apposition of vaginal mucosa, perineal body submucosa & rectal mucosa
a) Incise along junction of vaginal & rectal mucosa – dissect off to create flaps
b) Simple interrupted sutures on submucosa layer → vaginal → rectal mucosa
2. Closure of perineal body
a) Triangular closure with continuous horizontal mattress & simple interrupted closure
b) Caslick suture on skin
*Can do all sutures in one layer but increased risk of knot fragility
Post Surgery:
- Maintain gruel diet, grass, for 2-4 weeks post surgery
Prognosis: Post surgery:
- AI: 30 Days
- Natural Service: 3 month
- Pregnancy: 75%
- Recurrence: 3/20 recurrent tear
What is the Post Service/Foaling Vulval/Vaginal trauma?
Dorsal Vaginal Tear
- Communicates w/ peritoneal cavity
- Septic peritonitis (Abs & lavage)
- Small tears heal via 2nd intention
- Risk of intestinal herniation
- Large tears via suture/laparotomy
Vulval Lacerations
- Primary/delayed repair
Tx: Caslick +- Perineal body reconstruction
Vaginal Haematomas:
- Drainage
- Watch BV’s (Blood vessels) (Tie off)
- Tx: Caslick
What is a Caslick?
A caslick is used to suture the vulvar lips closed to prevent aspiration of air and faeces.
Due to:
- Poor vulval conformation
- Reduce vestibular faecal contamination
- Local Infiltration
Method:
- 3-4mm strip muco-cutaneous junction from pelvic brim dorsal commissure
- Forward continuous interlocking
- Absorbable vs non-absorbable suture
- Dorsal suture bite most important
What is Pouret’s surgery?
- Surgical correct of poor perineal body/vulval conformation: Cranial slope/sunken in perineal body
- Transverse dissection along perineal shelf: Hang large forceps off skin/stay sutures perineum and allow to granulate
What is urine pooling?
Cause: Vagina sloping in multiparous mares: Predisposes to endometritis and infertility
Treatment:
1. Caudal relocation of transverse urethra fold
- Resect mucosal strip either side of vestibule & urethral fold, caudal advancement 2-5cm & suture
2. Caudal urethral extension:
Foley catheter in urethra for 10-14d, create 2x lateral mucosal flaps – invert & suture
Px:
- 12% fistula formation
- 80-95% mares pregnant
- Breed 1 m
What are cervical lacerations?
Cause: Dystocia
Treatment:
- Delay surgery 4 weeks
- <50% repair of questionable value
- Debride margins, split into 2 layers, horizontal pattern in cervical mucosa (invert) & vaginal mucosa (Evert)
Px: 60-80% pregnancy, 25% repeat lacerations
What are the causes of adhesions?
Adhesions
Cervical:
Cause - Dystocia/cervicitis. Tx: Manual/laser resection OR foley catheter
Vaginal:
Dystocia/vaginitis → pyometra.
Tx: Manual/laser resection BUT recur/guarded/poor px
Explain Uroliths
Type 1: – Soft CaCo3
Type 2: Firm CaCo3 + Po4 + Mg
CS:
- Haematuria/dysuria/ogliuria
- Ab pain (Renal/ureteral)
- Wt. loss
Types of Uroliths:
- Cystoliths (Bladder):*Most common
Dx: Endoscopy, transrectal palpation, ultrasound
- Nephroliths:*2nd most common
CS: Weight loss!
Dx: Renal US
Prevention: ↑ Dietary NaCl, Urinary acidifiers (Ammonium Cl, Ascorbic acid)
Px: Fair-good except in renal, 7/15 recur
Treatment:
- US lithotripsy (calculi broken down into small particles to passed through the body)
- Electrohydraulic lithotripsy
- Pulsed dye laser
- Holmium laser
- Pararectal cystotomy
- Laparo-cystotomy
Mare: (Cystolith)
Manually dilate ext. urethral os & remove/fragment with mallet & osteotome → lavage → Maintain Foley catheter for 5-7 d (Transient incontinence)
Males: (Cystolith)
- Surgical Intervention
– Open via Paramedial incision
-Blunt dissection from mucosa & removal, close via simple continuous/cushing pattern (Mucosa) → lambert pattern (Serosa)
- Ischial urethrotomy & mechanical lithotrite
Method: Incise through retractor penis m. & insert lithotrite
Complications: Urethral stricture, rectal tear
Explain cryptorchidism in horses
Failure of testes to descend
Normal testicular development
- Equine Gonads form Form: 27d gestation
- Testicular Differentiation: 40d
- Vaginal process forms: 45-50d
- Testes Hypertrophy: 5m
- Regression of testes & shortening of gubernaculum: 8-9m
- Dilated gubernaculum, vaginal ring contraction. & testes passing into inguinal canal: 270-300d
- Testes reach scrotum: 315d gestation → 14d post partum, left testes descends later, unlikely to descend if > 2y/o
Contributing factors of testicular descent:
↑ Intra-ab pressure, everting vaginal process, gubernaculum guides testes & enlarges inguinal canal
Hosts: 16% 2-3y/o colts – esp., Percherons, Saddle & Quarter horses
Location: : L & R equal freq. of retention, L – 75% Ab retention, R – 58-76% Inguinal, bilateral – 13%
Describe the treatment and diagnosis for cryptorchidism
Aetiology:
- Autosomal recessive/dominant modes of inheritance
- Persistent suspensory lig. of testes
- Testicular abnormalities, e.g., cyst
- Excessively enlarged gubernaculum
- Failure of gubernaculum enlargement, vaginal ring dilation or inguinal canal dilation
Diagnosis:
- Scrotal palpation
- Transrectal exam
- US: Percutaneous, transrectal
- Endocrinology:
Serum testosterone:
Has seasonal, age & diurnal variation – LH dependant: LH peak –> peak testoesterone
Parameters:
Castrated - <40pg, Testicular tissue - >100pg, Cryptorchid – 200-100pg, normal – 1000-2000pg
hCG:
LH-like activity on the Leydig cells to produce testosterone, 94% accuracy
Variation in abdominal testes, <18m old, winter months
Time 0 sample: 9am 6000-12000IU hCG → Time 2hr & 24hr → Testicular tissue >100pg
Oestrone Sulphate:
Serum/faecal testing 96% accuracy >3y/o →
Geldings <50pg, Stallions >400pg
SURGERY:
- Non-Invasive Inguinal:
- GA & dorsal recumbency, Scrotal incision, blunt dissect laterally to superficial inguinal ring
- Identify inguinal extension of gubernaculum (Scrotal lig.) at cr. Lateral/medial superficial ring
- Grab extension w/ sponge forceps to evert vaginal tunic & incise (AVOID genitofemoral n)
- Apply traction on the tail of epididymis, attached ligament & proper lig. of testes
- Closure via ligation of vaginal tunic, second intention healing, adequate drainage OR primary
- Must close superficial ring if over 2 fingers wide & pack - Invasive Inguinal:
- Scrotal or inguinal incision, direct penetration of vaginal ring w/ >2 fingers
Adv: Faster than non-invasive inguinal Dis: Trauma to ext. pudendal vessels +- potential evisceration - Para-inguinal:
- 5-6cm incision cranial/parallel to external inguinal ring through SC, Ext.& Int. ab, internal mm. sheath & peritoneum & sweep vaginal ring for testis
- Closure w/ 2-3 vicryl SC/inverted cruciate in ext. rectus mm. sheath & 2-0 SC, 1 PDS skin - Ventral Midline:
Adv: Useful for bilateral & ensures secure close
Dis: ↑ Sx time, hard to exteriorise testis - Laparoscopic:
- Standing to avoid GA through flank portals OR DR via ventral portals
Adv: Useful for Dx, ↓ morbidity Dis: ↑ Cost/time/expertise
Describe other testicular/scrotal conditions
Orchitis
CS: Unilateral scrotal swelling, oedema, fever, pain on palpation, ipsilateral hind limb lameness
Tx: Antibiotics/anti-inflammatory
Scrotal Neoplasia
Types: Sertoli cell tumour, seminoma Tx: Unilateral castration – closed or semi-closed
Testicular Torsion
Rotates along vertical axis within the vaginal tunic
CS: Only 360o = colic, ischaemia, necrosis
Tx: 180o may resolve spontaneously, Orchiopexy (Not recommended) or unilateral castration
Describe scrotal/inguinal hernia
Hosts: Common congenital in standardbreds or mature stallions post-service (EMERGENCY)
Cause: Intestine passes through internal inguinal ring within the vaginal tunic
CS: Intestinal strangulation → Severe colic signs
Inguinal Rupture: GI passes through hole in body wall adj. to internal inguinal ring inside scrotum but outside vaginal tunic
Ruptured Inguinal Hernia: GI passes through internal inguinal ring through hole in vaginal tunic to lie in scrotum but outside vaginal tunic
What is Paraphimosis?
Inability to retract penis
Cause:
- Trauma
- Neural damage (Deep perineal, caudal rectal n.)
- Spinal trauma
- EHV-1
- Phenothiazine (ACP):
Sympatholytic to smooth m. cavernous sinus → Vascular pooling & penile prolapse → oedema → fatigue of retractor penis mm & pudendal n. → Fibrotic preputial ring
What is Penile Trauma?
Cause: Hx of being kicked by mare
CS: Dorsal haematoma (Ruptured dorsal veins.) → if untreated Develop into paraphimosis & infertility
Tx:
- Medical: Hose, emollient, sling, NSAIDS, tetanus, PPG
- Acute: GA, staggered 15 blade stabs & Esmarch → replace prepuce & buhner stitch 7-10d
- Chronic: Amputation, phallopexy
What is phimosis and priapism?
Phimosis
Inability to extrude penis from prepuce
Cause: Torn preputial suspensory lig., neoplasia, traumatic cicatrix
Tx: Wedge resection to enlarge preputial orifice
Priapism
Persistent erection
Cause: ACP admin
Tx: Corpus cavernosum lavage (Saline), Corpus cavernosum/spongiosum shunt
Describe penile amputation aka phallectomy
Indication:
- Neoplasia *IF albuginea/glandular involvement
SCC (Squamous cell carcinoma) –
45-70% all equine neoplasms, 6-15% Mx rate, 60% long term survival
Melanoma
- Trauma
- Paraphimosis
Complications: Haemorrhage, urethral stricture, recurrent neoplasia (20%)
Method:
- Catheter placed in urethra, incise along shaft through urethral mucosa, Corpus spongiosum
- SI attachment of catheter → transect penis only as far caudal as preputial reflection
- OR En bloc resection & retroversion
What is penile necrosis?
Cause: 2nd to surgical trauma → mis-identification of penis as testicle = transection of penile artery. & dorsal penile veins
