Routine elective procedures, including ovariohysterectomy, castration, dewclaw removal and feline declaws, are the most common
procedures in veterinary medicine. Because of their routine nature, it is easy to put little thought into the materials and
methods used for ligation of transected vessels and closure of the wounds. While these procedures are straightforward, overall
complication rates have been reported of 1 to 24 percent, with severe complication rates of 1 to 4 percent. Contemporary suture
and wound closure manufacturers currently provide the practicing veterinarian with an ample armamentarium to provide safe
and reliable wound closure. Critical evaluation of the materials and methods used in the procedure can be beneficial in reducing
In addition to medical factors, economic factors will affect the choice of suture material, patterns and the use of stapling
equipment. The cost of the material and equipment must be considered and viewed in light of savings in time and patient morbidity.
Use of vascular clips in general surgery
Ovarian pedicle hemostasis can be achieved through the use of suture or stapling devices. Factors influencing the choice of
materials used for hemostasis include the size of the patient, the amount of perivascular fat in the pedicle, the friability
of the pedicle, the stage in the heat cycle, security of the hemostatic method, cost of the materials, ease of application
and individual preference. There are a large number of methods and materials which can be considered. Some of the details
and benefits of each will be discussed.
The most common methods of hemostasis of the ovarian pedicle involve one or more ligatures. The choice of ligature pattern
depends heavily on the size and friability of the stump. A single encircling ligature is appropriate for small ovarian pedicles
without much perivascular fat. Most surgeons will choose to place a second ligature for increased security. In larger pedicles,
a transfixing ligature or Miller's knot is often used.
Suture material chosen for ovarian pedicle hemostasis should be strong, allow good tightness of the ligature to be achieved,
and provide good knot security. Generally absorbable suture materials are chosen, however non-absorbable suture material can
also be used. Given the affordability, strength and good handling characteristics of modern monofilament absorbable sutures
make them a good choice for pedicle ligation. It is important to tie square knots, use five to six throws and leave 5 mm tails.
A simple stainless steel vascular clip can be used to ligate smaller ovarian pedicles, like those in cats and small dogs (Figure
1, p. 10). It is helpful to use a vascular clip that closes first at the tip to avoid slippage of the ligated material. This
device is best used on ovarian pedicles in small dogs, ferrets, rabbits, reptiles and cats. The tissue to be ligated must
fit comfortably in the jaw of the instrument and one should avoid the temptation to include more tissue. Vascular clips are
also useful in splenectomy, amputation and ligation of the short gastric vessels, but can be useful in ligating any small
vessel. The vascular clips are intended to be left permanently in place.
Figure 1: A stainless steel vascular clip is used to ligate smaller ovarian pedicles like those in dogs and cats.
The devices can be resterilized by ethylene oxide or Sterrad®. These devices apply a single vascular clip of approximately
7 mm in length. Their primary advantage is the speed and ease of application. The ovarian pedicle can be double ligated in
a matter of seconds.
Larger ovarian pedicles are too wide for a single vascular clip. These pedicles can be ligated using a synthetic monofilament
or braided absorbable suture.
This structure can present problems as it may be very large and friable in an older animal. In some cases, the use of a circumferential
ligature is not appropriate. I recommend using an absorbable monofilament transfixing ligature for the uterine artery and
vein. The actual stump can be oversewn using a single continuous suture pattern, a horizontal mattress or a conventional Parker-Kerr
closure. It is important to securely close the uterine lumen.
Spermatic cord ligation
I recommend using an open castration method so that the blood vessels are ligated separately from the tunica. In some cases,
we have observed significant post-operative hemorrhage due to retraction of the spermatic vasculature. One can safely use
an absorbable monofilament suture or a vascular clip. I recommend the use of double ligatures or vascular clips on each testicular
artery and vein.
Body wall closure
Secure and safe closure of every abdominal incision is paramount. We routinely use a simple continuous suture of an appropriately
sized absorbable monofilament. When using a simple continuous method of closure, one should begin and end with simple square
knots with two to three extra throws. In general, when using sutures for ligation or closure, it is important to use proper
square knots, use five to six throws on each knot and at least 5-7 mm tails. It has been shown that continuous incorporation
of the peritoneum with the body wall is not necessary; however, I prefer incorporating the peritoneum whenever possible. Continuous
closure of the peritoneum is more important in cases with impaired wound healing or an abdominal transudate or exudate.