Spaying (ovariohysterectomy, OHE) cats is a surgical procedure performed daily in many thousands of veterinary practices around the world. The traditional method for an OHE involves tying ligatures of suture around the pedicles (bundles of blood vessels) supplying the ovaries. A newer technique involves “autoligating” the pedicle by tying it in a knot around itself. This is commonly referred to as a “pedicle tie” (PT). Pedicle ties minimize the amount of suture material used and are faster than traditional spay methods.
This study was of particular interest to me as I have been performing pedicle ties almost exclusively in my practice for several years. In my personal experience, this method of spaying cats is not only quick; it is also very secure and minimizes the amount of foreign material left within the feline abdomen. Shorter surgical times minimize the duration of anesthesia, decreasing the risk to the cat. However, there is a lack of information in the literature regarding the rate of complications with this procedure and whether surgical times are significantly shorter.
To attain this information, three experienced surgeons performed 2136 spays using the PT technique. Approximately half of cats were from a low cost spay neuter program, and the remainder owned by the humane society. In the second phase of the study, surgeons were timed performing traditional OHEs or PTs in kittens and adult cats, with each of the four groups including 40 cats. Cats in estrus or pregnant cats were not excluded.
Of the 2136 cats, 6 (0.281%) experienced hemorrhage of the ovarian pedicle. 5 of these were identified intra-operatively and corrected before the end of surgery. In one cat (0.048%) hemorrhage was identified post operatively and corrected via a second surgery. 4 cats experienced bleeding from other sites, including the uterine stump and broad ligament, unrelated to the pedicle tie. None of the cats experiencing complications were pregnant or in-estrus.
Surgical times were significantly shorter for pedicle ties vs traditional OHE in kittens (4.7 vs 6.7min) and adult cats (5.0 vs 7.0 min). This time benefit is significant- in the authors’ estimation, preforming a traditional OHE rather than pedicle tie would have resulted in an extra 2 weeks of work over the course of the surgeries.
This paper did not identify complication rates associated with traditional OHE, which represents a significant drawback. They site a previous study reported a 4% rate of hemorrhage, a figure that seems remarkably high. While a direct comparison is not available, it is difficult to disagree with the statement that a 0.281% complication rate, with only 0.05% occurring post-operatively is well within acceptable margins.
Several limitations existed in this study, including the inability to blind surgeons to the procedure, reliance on owner reporting of complications, and recent experience of the surgeons with the PT method.
The author’s conclusion was that PT OHEs are as safe as traditional OHEs, and are significantly faster. While a decrease in surgical times may provide a large economic and practical benefit in high volume spay/neuter practices, even in regular practice a briefer anesthesia may lead to improved outcomes for the animal, including lower risk of hypothermia and hypotension. Minimizing foreign material in the cat’s abdomen minimizes the risk of inflammation, infection, or reaction to these sutures. While this paper is far from an indictment of traditional methodology, it does provide evidence that the PT is a safe and viable alternative that is at least equivalent and potentially superior to traditionally OHE. (MRK)