RVETS Castration Protocol

Steps to a routine castration:

  1. Identify two testis.
  2. Block each cord (or testis if small) with 10ml of 2% lidocaine in each cord or testicle.
  3. Prep surgical area by scrubbing with betadine EZ scrub for ~1 minute followed by rinse/wipe with roll cotton and betadine solution until all scrub has been removed.
  4. Identify the median raphe.
  5. Make 2 incisions, ~2cm from median raphe on each side. Incision should extend the entire length of testis. Testicles should be grasped at cranial aspect in order to taught skin prior to incision. In foals, it may be easier to stretch skin flat against the body wall rather than trying to grasp testicles and incise directly over the testis. If using this technique, caution should be taken to avoid incising underlying large superficial vessels and/or incising too deeply. Incisions should be made to level of vaginal tunic, but no deeper in order to perform a closed castration. 
  6. Bluntly dissect fascia in incision of “down” (closer to the ground) testicle.
  7. Exteriorize “down” testicle and continue to bluntly dissect fascia and “strip the cord” of all fascia until cremaster muscle and cord are clearly visualized. Use of bronchial forceps to grasp the testicle or making a small incision in the testicle to make a “finger hold” will facilitate holding the testicle with one hand while stripping the cord with the other hand.
  8. Tear or emasculate cremaster muscle.
  9. Once the cord is stripped and cremaster muscle torn, pass the testicle to the surgery assistant to hold (if available). If you are performing the surgery without an assistant, clamp the cord between the handles of the bronchial forceps, as close to the body wall as possible.
  10. Place transfixed modified Miller’s knot around cord as proximal (away from the testicle toward the body wall) as possible.
  11. Emasculate cord distal 1-2” distal to ligature. 
  12. Remove emasculators and repeat process of blunt dissection, ligation, and emasculation on other testicle. If 2 pairs of emasculators are available, the first pair can be left in place while the second testicle is removed, but this is not necessary for hemostasis.
  13. Immediately following the second emasculation, remove all emasculators in place and stretch each skin incision.  While stretching each incision, visualize the “stump” of ligated cord. Check for bleeding from the ligated cord or elsewhere.
  14. Trim fascia protruding from incision, taking care to ensure no large vessels are within the fascia.
  15. Clean area with clean roll cotton and betadine solution.
Proper placement of emasculators with nuts of the emasculator on the same side as the testicle.

General notes regarding castration procedure:

Prepare for surgery prior to the patient becoming recumbent.  Check that you have:

  • Red surgery bucket filled to just below the magnets with water. Add betadine solution to form a strong tea color.
  • Gloves
  • Blade loaded onto scalpel handle
  • Suture
  • Emasculators
  • Needle drivers
  • Scissors
  • Bronchial clamp
  • Mosquito forceps

Position your equipment behind the patient’s leg, within your reach.

Squat or kneel (on one knee) behind the patient. Place your shoulder against the inside of the patient’s leg so that you can feel if the patient is starting to move its hind legs and avoid being kicked by the patient.

All team members should be prepared to perform their assigned tasks prior to the patient becoming recumbent.   You should always know your assigned task for the current procedure, and for the next.

Once the patient is recumbent and adequately anesthetized the rest of team should move quickly to complete their assigned task/tasks as efficiently as possible.  

Do not rush the patient. Wait until they are fully relaxed to proceed. The upper leg should be resting on the ground and you should have the go ahead from the anesthesia team before placing the leg rope.

Everyone involved in the process must remain on the horses back side, which is the side away from the hooves.

The exception to this is if you are doing a procedure involving the leg or foot.

Prior to the patient becoming recumbent each team member should check that all supplies are ready for the patient.  Each member of the team has an assigned task.

Each time you reach into the vaccine cooler, feel the ice packs.  Vaccines must not be allowed to become warm.  If the ice packs are not frozen, replace them immediately.

Maintain all necessary equipment and drugs so that they are easily available, clearly labeled, and easy to move (this is particularly important in an emergency, and you never know what you will need). DO NOT carry supplies in pockets (they will fall out when you bend over) or in an arm load (you will drop them). We have caddies, buckets, bucket buddies, and toolboxes for this purpose.  Blades, needles and syringes must be put in the caddy immediately after use to avoid their getting lost. 

Volunteers are responsible for adequately preparing for the day’s work by checking that there are sufficient:

  • Forms
  • Vaccines
  • Cooler/Ice packs
  • Sterile surgical gloves
  • Garbage bins
  • Buckets
  • Sharps containers
  • Caddies
  • Fly spray
  • Syringes
  • Needles
  • Blades
  • Lidocaine
  • Banamine
  • PPG
  • Snacks/lunch
  • Drinking water 
  • Filled water carboys if no convenient access to running water available
  • Equine pharmacy
  • The equine surgery box-fully stocked
  • Hoof trimming tools

Support team responsibilities:

Placing the leg rope

  • 3/4“rope of adequate length (15-20 feet) is the rope of choice for adult horses
  • 5/8” rope 12-15 feet long is more suitable for minis, ponies, foals and/or burros
  1. Once the anesthetist has given the go ahead, raise the “up” hind leg and flex the leg by flexing the fetlock and placing pressure on the plantar aspect of the cannon bone. Stand so that you are in contact with the cannon bone so that if the patient moves you will be pushed, not kicked.
  2. Place the noose around the pastern.
  3. Figure eight twice around the hock and pastern, ending at the pastern.
  4. Place a half hitch at the pastern.
  5. Step back from the patient, standing on the back side of the patient and lifting the leg up and away from the ground.
  6. Pass the rope behind your back and sit back on the rope, allowing your weight to do the work.
  7. DO NOT TIE THE ROPE AROUND YOURSELF

Performing the lidocaine block

2% lidocaine is instilled into the cord or testis to paralyze the cremaster muscle in order to facilitate exposure of testis as well as to minimize stimulation caused by manipulating the testi and stripping the cord.

  • Use a 20ml 2% lidocaine in a 20ml syringe with an 18 gauge needle attached.
  1. If there is a large amount of gross debris on the scrotum, quickly clean the area with roll cotton and betadine solution prior to performing the block.
  2. To isolate the spermatic cord, grasp the cranial aspect of the testicle between your thumb and index finger and pull upward. The cord should be isolated between your fingers if grasped properly. Insert the needle where the cord rolls over your thumb and index finger, aspirate to insure you’re not in a vessel, and inject 10ml into each cord. To work your needle MUST be in the cord.  The block will not migrate across the tunic. Isolating the cord can be more challenging in young patients with small testis. In this case, 10ml lidocaine can be injected directly into each testicle.      
  3. If no blood was aspirated during the procedure, return the syringe with the needle attached to the caddy as it will be reused for the next patient after the needle is changed. If you aspirated blood when performing the block, discard the syringe and needle and get a new syringe for the next patient.

Prepping the surgical area

  • The blue bucket is used for surgical prep. The bucket should be filled with water and then betadine solution added to form a strong tea colored solution. Adding chunks of roll cotton to this solution. A new EZ scrub brush is used for each patient. The brush should be opened prior to the surgery and placed in the bucket.
  1. Place the blue scrub bucket close enough to the patient that you can reach it while scrubbing the inguinal/scrotal area.
  2. Use one hand (your “clean” hand) to reach into the bucket to grab things then transfer the scrub brush or cotton to your other hand (the “dirty” hand) to touch the patient.
  3. First grab the EZ scrub brush from the blue bucket and scrub the patient’s scrotum, area caudal to the scrotum, area cranial to the scrotum up to the sheath, and lateral to the scrotum to the inguinal ring on either side. If there is a lot of gross debris, use the brush side of the sponge initially to remove, then switch to using the sponge side. Scrub for ~1 minute. Discard the brush in the trash when you are done with it. Do not place it back in the bucket.
  4. Rinse and wipe away the betadine scrub using the roll cotton in betadine solution. It may take several rounds of roll cotton to remove all scrub. Discard the pieces of cotton in the trash when you are done with them. Do not place them back in the bucket.
  5. As with any surgical prep, start with the site where the incision is to be made (the scrotum) then gradually work outward in a surgical direction.

Recording treatments, surgery, and anesthetic notes in the medical record

For each patient, a scribe should be assigned to complete the medical record. If there is no scribe, generally the anesthesia team will be in charge of completing the record. The top section should be completed with owner’s information (name, address, phone number, email). The needs to sign for authorization to perform anesthesia.

The following should also be recorded for each patient:

  • BCS 
  • Age
  • Patient description (color, markings)

The following treatments will be administered to each castration patient and will be recorded in the record:

  • Vaccines (tetanus +/- other)- for tetanus vaccines place a check mark in the corresponding box, for all other vaccines, indicate the type of vaccine administered
  • Banamine (flunixin)- write the number of mls of flunixin administered in the corresponding box
  • PPG- write the number of mls of PPG administered in the corresponding box

State clearly and audibly what you are administering and by what route as you do so. Each step performed during a team effort should be stated clearly in a loud enough voice for the entire team to hear. This will prevent patients from receiving the same treatment twice and will allow the scribe to record all pertinent information.

Always verify what is in the syringe prior to administration.  Do not administer any drug if you do not fully understand what its function is, how much the patient should receive, and by which route the patient should receive it.

NOTE:  All team members should be familiar with all tasks and supplies necessary to complete the castration process.  Never stand idle if all equipment and supplies are not ready for the next patient.