The old versus the new: alternative spay and neuter techniques

nataba / stock.adobe.com

When it comes to spay and neuter surgery, the veterinary profession has seen increases in advancement and public awareness in the past decade. Low-cost and mobile clinics have gained popularity, and high volumes of spay and neuter are performed at humane societies and shelters. As in all aspects of veterinary medicine, veterinarians are introducing new techniques to perform these procedures.

According to Kirk Miller, DVM, ABVP, although spay and neuter procedures have always been done a certain way, multiple techniques exist to perform these surgeries. He noted how important it is to keep up with changes in spay and neuter techniques during his lecture “Alternative Spay/Neuter Techniques” at the Fetch dvm360® conference in San Diego, California. Miller also broke down different procedures and treatments along with the research behind them.¹

Canine neuter

Prescrotal approach

The traditional procedure for neutering canines commonly taught in veterinary schools has been the prescrotal approach. According to Miller, the surgeon advances each testicle cranially to the scrotum and incises the skin and facial layers over each one. The surgeon then individually removes and double ligates the testicles.¹

Scrotal approach

To deal with high volumes of spay and neuter cases, the scrotal approach has been gaining popularity at veterinary schools. For this technique, the surgeon stabilizes each testicle and makes a single skin incision directly over the scrotum. The surgeon then removes each testicle and performs a double ligature or a ligature with a single knot.

After this procedure, the surgeon closes the subcutaneous or facial layer but may leave the incision open for drainage and healing by second intention. They may also close the incision with cyanoacrylate tissue adhesive.¹ Proponents of this latter technique believe the tissue adhesive will give the surgical wound an immediate barrier along with its hemostatic and bacteriostatic properties, according to Miller.

Sutureless scrotal castration

In a study published in the Journal of the American Veterinary Medical Association (JAVMA), multiple veterinarians, including Miller, investigated the scrotal approach and its benefits. From a group of 418 shelter dogs, researchers found that sutureless scrotal castration (SLSC) was safer and faster compared with traditional prescrotal castration (TPSC). The investigators also noted that SLSC had the potential to improve morbidity and mortality rates in canines.²

This newer method is used for pediatric and juvenile dogs in high-quality, high-volume spay/neuter facilities. For this technique, the surgeon makes a single incision on the ventral midline where both testicles are accessed. The surgeon may opt for an opening of the vaginal tunic or a closed castration. Following this, Miller explained, the testicles are individually exteriorized with the hemostat twisted to form an overhand knot in the spermatic cord. The surgeon then cuts the spermatic cord distal to the hemostat and places the cut end over the end of the hemostat to complete the knot. The scrotal skin incision is then closed using a cyanoacrylate surgical skin adhesive. However, Miller noted some surgeons opt to leave the incision open for draining and healing by second intention.¹

According to the JAVMA study, the sutureless scrotal technique was demonstrated to be a safe and efficient castration method for juvenile and pediatric canines.²

Feline spay

The traditional method

The traditional method taught at most veterinary schools involves the double ligation of the ovarian pedicle. The surgeon performs a ventral midline celiotomy and locates the uterus using a spay hook (or Snook hook). After placing a hemostat on the proper ligament, the surgeon tears the ligament with the hemostat or cuts it with a scalpel blade. This allows the ovary to be exteriorized.

Next, the surgeon creates a window within the broad ligament to isolate the ovarian pedicle and places a hemostat across the vascular pedicle proximal to the ovary. Two different absorbable suture ligatures are placed around the pedicle prior to transection. The surgeon then repeats this procedure on the other side before exteriorizing and double ligating the uterine body. At the discretion of the surgeon, a transfixing suture may be considered. After removing the uterus and both ovaries, the surgeon closes the incision.¹

Pedicle tie

For this technique, the ovarian pedicle is “auto-ligated” in the same manner that a surgeon ties the spermatic cord on itself in feline castration. For this ventral procedure, the surgeon performs a midline celiotomy and locates the uterus using a spay hook. Then, after placing a hemostat on the proper ligament, the surgeon tears the ligament with the hemostat or cuts it with a scalpel blade. By doing this, the surgeon allows the ovary to be well exteriorized and creates a window within the broad ligament to isolate the feline’s ovarian pedicle.

Miller explained that through this procedure, a hemostat is directed parallel to the ovarian vascular pedicle and pointed in a proximal direction. The surgeon twists the hemostat to form a simple overhand knot in the vascular pedicle, then cuts it distal to the hemostat. To complete the knot, the surgeon slips the cut end over the end of the hemostat, then repeats the procedure on the other side.

After removing the uterus and both ovaries, the surgeon closes the incision. One may close the incision using an intradermal suture pattern or a cyanoacrylate surgical skin, Miller explained.¹

Conclusion

Whether veterinary professionals stick to the traditional procedures of spaying and neutering or change to a new method, Miller stressed the importance of doing research to evaluate these techniques and their safety. He hopes that veterinary professionals will welcome recent graduates with experience in these techniques as well as those who would like to learn more about them. Miller believes educating yourself on the new techniques, even if you like the traditional ones, has the potential to make these important treatments safer.¹

References

1. Miller KP. Alternative spay/neuter techniques. Presented at: Fetch dvm360® Conference; December 3-5, 2021; San Diego, CA.
2. Miller KP, Rekers WL, DeTar LG, Blanchette JM, Milovancev M. Evaluation of sutureless scrotal castration for pediatric and juvenile dogs. J Am Vet Med Assoc. 2018;253(12):1589-1593. doi:10.2460/javma.253.12.1589