Download - Large Animal Orchiectomy
Large Animal Orchiectomy(Castration Lecture)
Dane Tatarniuk, DVMResident, Large Animal Surgery
April 5th, 2013
Terminology
• castration, • orchiectomy, • emasculation, • gelding, • cutting,
Equine Castration
• Overview– Age– Indication for surgery• Behavior• Neoplasia• Inguinal herniation• Testicular trauma
Anatomy
• Scrotum• Testicle• Epididymis• Tunica
Vaginalis– Parietal Tunic– Visceral Tunic
• Inguinal Canal
Anatomy
• Spermatic Cord• Cremaster Muscle
Pre-operative Considerations
• Systemically healthy• Palpation– Two testicles descended?
• Vaccination– Tetanus
• NSAIDs– Bute, Banamine
• Antibiotics– Penicillin, Ceftiofur
Supplies
• General instrument pack • Sterile gloves • Scrub • Emasculators • Suture • Ropes • Towels • +/- IV catheter
Standing Castration• Advantages
– Less cost & assistance– Quicker– Choice if poor anesthetic candidate
• Disadvantages– Vulnerable position– Avoid on small horses, donkey’s, mules– Assess temperament prior
• Sedation– Alpha-2 agonist +/- butorphanol
• Local Analgesia– Essential to castrating standing– Spermatic cord or intra-testicle
• Position– Tight to horse, keep head up, use reach of arms.
Recumbent Castration
• Environment– Field conditions– Hospital conditions
• Anesthesia • Xylazine followed by
ketamine & diazepam
• Recumbancy– Left lateral vs. dorsal
• Rope Restraint– Tie the limbs to
maintain safety
Open Castration
• Incision– Through both scrotum and
parietal tunic• Dissection
– Ligament of tail of epididymis• Exteriorization
– Testicle and spermatic cord• +/- Ligation
– Hemostasis– Foreign material
• Emasculation• Leaves parietal tunic behind
Emasculation
• “Nut to Nut”• Held clamped for
minimum of 1 minute– Anecdotal rule of ‘1
minute per age year of horse’ often used
• Variable types of emasculators– Serra, White vs. Reimer
Closed Castration
• Incision– Only through scrotum, not
through parietal tunic• “Stripping”
– Dissection of scrotal fascia• Emasculation
– Parietal tunic vs. Cremaster muscle
• +/- primary closure– Decrease risk of herniation
and evisceration – Foreign material
Semi-Closed
• Incision– Scrotum– 2cm incision into parietal
tunic• Eversion of tunic
– Flip parietal tunic over thumb– Provides grip to aide in
retraction• Closed castration
– Emasculate spermatic cord followed by parietal tunic
Scrotal Healing
• Second Intention Healing– Drainage– Stretching incision– Trim excess fascial tissue
• Primary Closure– Technique
• Excellent hemostasis
– Environment• Sterile operating conditions
– Increased cost
Other
• Already anesthetized• Remove wolf teeth– 505 & 605
• Interfere with bit placement in the mouth
Post-Operative Recommendations
• Open Scrotal Incision– Movement
• Lunging at the trot daily
– Hydrotherapy• Decrease swelling
• Closed– Confinement to facilitate primary intention healing
• Isolation from mares– Active spermatozoa – 2 days min.
Complications
“The one who does not operate, does not have complications.”
Hemorrhage• Emasculator application
– Thick cords– Angle non-perpendicular– Instrument condition
• Testicular Artery– Some dripping normal, from scrotal vessels– Active stream of blood is not normal
• Treatment– Wait 20 – 30 min, observe– Sedate, re-grasp cord, ligate– Pack with gauze for 24 hours– Anesthetize and find bleeder
• Monitor yourself– Stay on farm or refer
Evisceration
• Prolapse of intestine / omental tissue through inguinal canal and scrotum
• Breed– Standardbreds, Drafts
• Clean and replace contents back into abdomen– May have to anestheize– Refer immediately
• Sequela– Strangulation of intestine– Septic peritonitis
Edema
• Common, normal result• Management– Exercise– Hydrotherapy
• If non-responsive,– Re-open scrotal incision– Promote further
drainage
Septic Funiculitis
• Definition: Infection of spermatic cord
• Open castration– More tissue left behind
• Treatment– Antibiotics– Drainage– Surgery
• Champignon vs. Scirrhous Cord – Streptococcus vs.
Staphylococcus
Clostridial Infection
• Clostridium tetani– Spastic paralysis
• Clostridium botulinum– Flaccid paralysis
• Malignant Edema– Tissue necrosis, cellulitis, fever, depression,
toxemia, death • Poor prognosis
Septic Peritonitis
• Anatomy– Vaginal cavity communicates
with abdomen• Treatment– NSAIDs– Antibiotics– Peritoneal Lavage
• Referral
Penile Damage
• Inadvertent emasculation of penis• Edema formation• Paraphimosis• Know your anatomy
Hydrocele
• Scrotal swelling– Excess abdominal fluid in vaginal cavity
• Open castration• Cosmetic problem– Usually painless
• Drainage not helpful– More abdominal fluid– Can introduce bacteria
• Surgery– Remove parietal tunic
Behavior
• Perpetual masculine behavior• Learned response• Older stallions• Warm owners
Cryptorchidism• Definition: Failure of one or more
testicles to descend• Location
– Abdominal vs. inguinal– Left vs. right
• Inherited• Diagnostic techniques
– Palpation, ultrasound, exploratory, hormone assays
• Surgical removal– Do not remove a descended testicle
if the other testicle cannot be located.
Food Animal
• Principles of castration similar to equine
• Meat quality, behavior• Often performed by producer• Restraint alone vs.
sedation/anesthesia• Scrotal incision
– Overlying testicle– Transect distal 1/3rd
• Strip, +/- ligate, emasculate, etc.
Food Animal Tools
• Newberry knife– Splits scrotum in half– Good access– Good drainage
Food Animal Tools• Bloodless Castrators
– Elastrator– Callicrate
• Strangulation of vasculature -> atrophy -> necrosis• ~ 3 weeks• Small, young animals
Food Animal Tools
• Burdizzo– Crushes spermatic
cord from the outside
– May have to apply multiple times
– Testicles atrophy, don’t usually slough
Food Animal Tools
• Henderson castrating tool– Attached to power drill– Twisting motion– Good hemostasis in older animals
Conclusion
• Understand the anatomy, know your basic surgical principles, and evaluate the unique factors present (specie, purpose of animal, animal temperament, surgical environment, owner expectations, owner budget etc.)
• Recognize potential complications from castration and know how to manage them appropriately.
• There is no “one right way” to perform castration - the right way is to know every way and apply the appropriate technique to the individual / situation.