Laparoscopic neutering of the bitch has been available for three decades but has only been widely adopted in the last 15 years. It remains less common than traditional open ovariohysterectomy (OHE/OVH) or ovariectomy (OVx). This article will explore the pros and cons of each technique, drawing on published material where available together with the author’s experiences. It is not intended to be a guide to how to perform either type of surgery, although an outline of each is presented.
Overview of surgery technique
Laparoscopic neutering
A laparoscopic approach is routinely performed with two or three access sites (portals), usually placed through the ventral midline (Figure 1). The laparoscope is typically placed at or close to the umbilicus. A second portal is placed for an instrument caudal to this and some surgeons place a third portal cranial to the umbilicus for a second instrument (Figure 2). Typically, the ovary is grasped and held towards the ventral midline (with an instrument through the third portal or a percutaneous hook) and the ovarian pedicle is transected with a device that seals and cuts simultaneously (Figure 3). In most bitches, only the ovaries are removed. The uterus is removed in patients with pre-existing uterine pathology. Single-portal techniques are also described but are less common than either two- or three-portal techniques. It is common for the surgeon to require a scrubbed assistant during lap spays.
Traditional (open surgical) neutering
Traditional surgery is carried out through a midline laparotomy. The length of the incision depends on the surgeon’s preference but is often 30 to 50 percent of the distance from the umbilicus to the pubis. The surgeon may remove the ovaries and uterus (typical in the UK and USA, for example), or the ovaries alone (typical in many European countries). Normally the ovarian pedicle and the uterine body are ligated and then transected. Most bitches are neutered in this way with a single surgeon and without a scrubbed assistant.
Ovariectomy versus ovariohysterectomy
At open surgery or laparoscopic surgery, neutering can involve either OVx or OVH/OHE. In many countries, neutering has traditionally involved OHE, but the standard laparoscopic technique involves the removal of the ovaries only. Some clinicians and owners express concerns about the relative medical risks and benefits of OVx or OHE, which focus on the incidence of uterine disease after neutering and the development of urinary incontinence.
Uterine disease
One study looked at long-term health after OVx or OVH and found no difference, suggesting that removal of ovarian tissue without removing uterine tissue is effective in preventing pyometra development
Common uterine diseases of concern in the bitch are pyometra and neoplasia. Considering pyometra (for example, pyometritis and cystic endometrial hyperplasia complicated by bacterial infection), it is widely accepted that this only develops in the context of ovarian hormonal activity, suggesting that the pathology requires functional ovarian tissue or exogenous progestogenic therapy (Hagman, 2017).
Currently, there are no studies available that compare the long-term health of bitches neutered traditionally or by laparoscopy, but one study looked at long-term health after OVx or OVH and found no difference, suggesting that removal of ovarian tissue without removing uterine tissue is effective in preventing pyometra development (Okkens et al., 1997).
Urinary incontinence
The prevalence of urinary incontinence after laparoscopic neutering or traditional (open surgical) neutering is also unknown, but the same study showed no difference in long-term prevalence after OVx or OVH (Okkens et al., 1997). Urinary incontinence after neutering is multifactorial in cause, but existing anatomical configuration (position of the bladder neck and length of the urethra) and post-neutering hormonal changes are both important factors (Applegate et al., 2018). Although there is speculation that bladder neck position may change after hysterectomy, the author is not aware of evidence to support this theory in canines.
Given the lack of evidence of long-term differences in outcome from OVx or OVH, in most cases the surgeon can choose either technique. During laparoscopic neutering, most surgeons perform OVx routinely and OVH in selected cases (present or previous pyometra, suspected cystic endometrial hyperplasia, pregnancy). Laparoscopic OVH usually requires conversion from a pure laparoscopic technique (intracorporeal surgery only) to laparoscopic-assisted surgery (part of the surgery completed after exteriorisation of abdominal organs: in this instance, ligation and transection of the uterine body or vagina). There is some evidence that laparoscopic OVx is less painful than laparoscopic OVH (Gower and Mayhew, 2008), which is an additional reason for routinely performing OVx.
Post-operative recovery pain
Anecdotally, experienced surgeons who switch from traditional surgery to lap consistently report lower discomfort in their patients once experience has been gained
Publications looking at post-operative pain levels after laparoscopic neutering were reviewed recently (Webb and Deutsch, 2021). The conclusion was that there is weak evidence that laparoscopic surgery is less painful than traditional surgery. The limitations of all studies to date must be recognised: small sample sizes and absence of direct comparisons. A valid alternative interpretation of the studies is that the laparoscopic technique is no more painful than traditional surgery (no study to date has shown this). Anecdotally, experienced surgeons who switch from traditional surgery to laparoscopic neutering consistently report lower discomfort in their patients once experience has been gained, which is consistent with experience of laparoscopic surgery in people.
Complications associated with laparoscopic neutering
Study sizes often limit the comparison of complications associated with traditional or laparoscopic neutering techniques. However, one recent publication compared post-operative complications associated with laparoscopic OVx and open OVx (Charlesworth and Sanchez, 2019). This study used cases from one clinic and showed a lower incidence of wound complications after laparoscopic OVx. The types of complications associated with laparoscopic neutering in this study also tended to be less serious.
In the author’s experience with laparoscopic OVx, occasionally intraoperative conversion to open surgery is required (often because of technical difficulties with equipment, resulting in loss of inflation for example) but significant intraoperative haemorrhage is rare
Studies reporting intraoperative complication rates in a large series of cases are not available for either technique. In the author’s experience with laparoscopic OVx, occasionally intraoperative conversion to open surgery is required (often because of technical difficulties with equipment, resulting in loss of inflation for example) but significant intraoperative haemorrhage is rare. In the absence of a large study of traditional neutering-associated complications, a direct comparison is not possible. However, well-known complications are significant intraoperative or post-operative haemorrhage (occasionally life-threatening or requiring re-operation). The absence of good studies prevents analysis of confounding factors such as surgeon experience when comparing the two techniques.
Additional considerations
Procedure time
A common concern in clinics contemplating offering laparoscopic neutering is the difference in procedure time compared to traditional surgery. It is also complicated by the time allowed for equipment set-up (laying out the trolley and setting up the endoscopy tower), as well as the surgery time (skin-to-skin). Anecdotally, the set-up time for laparoscopic neutering is significantly longer than that for traditional surgery. This is both because of initial unfamiliarity with the specialised equipment and because more equipment is required. Clinics generally find set-up time reduces with repetition but typically remains longer than that required for open surgery.
Anecdotally, a surgeon and team that are practised can complete the laparoscopic procedure (skin-to-skin) in a similar time to open surgery. Set-up can be completed with or without involving the surgeon in no more than 10 minutes
Steps to minimise the set-up time for laparoscopy include investing in more than one set of instrumentation, processing instruments in sets (rather than packaging individually), investing in suitable sterilising equipment (suitable for the instruments used and of sufficient size) and training a small team of technical staff with responsibility for setting up for the procedure. Regardless, it is generally true that set-up will still take longer than for open surgery even when the clinic is well prepared.
Operating time (skin-to-skin) comparing open surgery and laparoscopic neutering has not been published. Comparisons are confounded by surgeon experience, access to assistance, choice of instrumentation and so on. However, Corriveau et al. (2017) report an average procedure time of 50 minutes for laparoscopic OVx. One step that can cause delay in larger bitches is repositioning during surgery. During lap spay, after portal placement the patient is usually rotated into a dorsolateral position for the first ovary and then rotated the other way for the second ovary. In small patients, this is conveniently and quickly done with simple positioning aids, but in larger patients, this can be slow and difficult. For these patients, a tabletop that rotates the patient easily from one recumbency to the other shortens the procedure time significantly and reduces operating room personnel requirements. Anecdotally, a surgeon and team that are practised can complete the laparoscopic procedure (skin-to-skin) in a similar time to open surgery. Set-up can be completed with or without involving the surgeon in no more than 10 minutes.
Tissue trauma
There has been some investigation using biochemical indicators of tissue trauma and physiological stress. One study (Del Romero et al., 2020) compared laparoscopic OVx to both traditional open surgical midline OVx and flank approach OVx. Levels of acute phase proteins, an indicator of tissue trauma, were lowest in the laparoscopic OVx group.
Cost comparison
The cost to the owner is set by the clinic in each case. However, the additional capital cost of the laparoscopic equipment is in the range of £20,000 to £40,000, and therefore clinics charge a premium for laparoscopic neutering. In the UK, the charge for laparoscopic neutering is generally threefold the price of traditional open surgery. This reflects the capital investment, additional skills required and presentation to clients as a premium service. There is client demand for this premium service in some populations and offering the service can be a “practice building” technique.
The choice for the owner
Circumstances when laparoscopic neutering appears more favourable are for large and active patients, particularly if post-operative rest is expected to be difficult to enforce, or an early return to normal activity for training or utility use is required
In selecting the technique, owners should be presented with the evidence around either technique. Although study sizes are generally small, the evidence tends to weakly favour laparoscopic neutering for post-operative recovery, but owners have to balance this against the additional cost. Special circumstances when laparoscopic neutering appears more favourable are for large and active patients, particularly if post-operative rest is expected to be difficult to enforce, or an early return to normal activity for training or utility use is required.
The choice for the clinic
Significant investment in training and capital equipment is required for laparoscopic neutering. However, many clinicians believe that the technique favours the welfare of the patients. Additionally, once the service has been established, it can increase the reputation and customer base of the clinic.
Final thoughts
There is ongoing active debate about the benefits and disadvantages of traditional or laparoscopic neutering for bitches. This article has considered the implications of each for the patient, clinic and owner to assist informed debate and decision making.
