Laparoscopic, laparoscopic ovariohysterectomy, laparoscopic ovariectomy.

Sterilization of female dogs is the most common surgical procedure performed in veterinary surgery (Van goethem, 2006). Spaying can be done by either OVH (ovariohysterectomy) or OVE (ovariectomy), where OVH is the most preferred method of spaying used worldwide. Many surgical techniques have been described for spaying such as laparoscopic procedures (Case, 2011) open midline laparotomy, and lateral flank laparotomy amongst which Laparoscopic procedure is considered as most efficient method. Many studies have been published so far comparing laparoscopic procedures and open surgical techniques for spaying (Janssens, 1991). Laparoscopic surgery is growing in popularity in the veterinary sector due to its benefits, including reduced surgical trauma, less discomfort following surgery, shorter hospital stays, and a quicker return to regular activities (Mayhew, 2011). Laparoscopic surgery presents a promising method for sterilizing a large number of dogs, allowing the dogs to be released in three days without experiencing complications such as wound dehiscence, hemorrhage, infection, or maggot infestation (Mahalingam et al., 2009). Laparoscopy provides good view of surgical field by magnification and illumination, which may decrease intra-operative and post-operative complications. Literature cited stated that LapOVH is advantageous because of less post-operative  pain and surgical stress as happens in open OVH (Davidson 2004; Devitt, 2005; Hancock, 2005) whereas LapOVE is better technique because of shorter recovery time compared to open OVE when post-operative recovery is compared (Van goethem, 2006). The current study was conducted to assess two distinct laparoscopic sterilization methods in a canine birth control program. 

This study was conducted on fourteen healthy bitches presented to Department of Surgery and Radiology, College of veterinary and animal science, Bikaner, RAJUVAS for elective sterilisation. All selected animal underwent ultrasonographic examination prior to surgery to rule out pregnancy, they were also tested for hemato-biochemical parameters to determine anaesthetic risks regarding health. The chosen animals were randomly divided into two groups, Group I and Group II, each consisting of seven animals.

All the bitches were preanesthetised with Atropine sulphate @ 0.04 mg/kg body weight IM (intramuscular) and Xylazine hydrochloride @ 1 mg/kg body weight IM and after 10 minutes Ketamine hydrochloride @ 5 mg/kg body weight IM was used as induction agent. Maintenance of anaesthesia in the dogs was performed by inhalation anaesthesia with Isoflurane USP.

Site over abdomenarea was aseptically prepared for the surgery after clipping the hairs from xiphoid region to pelvis. After application of surgical drape around the surgical site a small nick was applied near the umbilicus to facilitate the insertion of Veress pneumoperitoneum needle (Karl Storz GmbH & Co. KG, Germany). The abdominal cavity was inflated using carbon dioxide gas via veress needle at a rate of 2 L/min and a pressure gradient of 10-12 mmHg was maintained, using an electronic carbon dioxide endoflator and silicone tubing from Karl Storz GmbH & Co. KG, Germany. The veress needle was replaced with a 6 mm safety trocar and cannula unit (Karl Storz GmbH & Co. KG, Germany). Through the cannula, a digital camera (TELECAM 1-chip camera, Karl Storz GmbH & Co. KG, Germany) and a light source (KARL STORZ Xenon cold light source LED NOVA) were connected to a rigid-type telescope (Hopkins II straight forward 30-degree telescope, Karl Storz GmbH & Co. KG, Germany). The abdominal cavity was examined for any trauma by veress needle to trocar, the organs like urinary bladder was identified because of its architecture of twisted blood vessels and ovary and uterus are identified by their characteristic colour and cord like structure.

Under telescopic guidance, two other ports of 5mm each were created 4-6 cm para median and distal to the laparoscope insertion site for insertion of operating instruments and thus, the three ports were placed (Fig. 1).

In animals of Group I, Kelly grasping forceps were introduced by one side port (left) and the uterine horn bifurcation was identified by its characteristic “Y” shape adjacent to urinary bladder, it acts as landmark for both the ovaries. Now the ovary of other side (right) was approached following uterine horn bifurcation and it was pushed caudally to make the ovary, ovarian bursa, suspensory ligament and associated blood vessels visible. Then using Karl Storz bipolar electro cautery forceps through the right side port, the suspensory ligament, including the arteries, was grabbed and cauterized (Fig. 2). Then, the remaining mesovarium structure was electro cauterized using electro cautery forceps, and all of the cauterized structures were cut using Click line scissors (Fig. 3) (Karl Storz GmbH & Co. KG, Germany). The uterine horn was grasped near the ovarian bursa and was cauterized using bipolar electro cautery forceps (Fig. 4). Through a side port, the entire ovarian bursa was removed after being dislodged (Fig. 5). The same procedure was followed for the left side ovary. Finally the carbon dioxide from the abdomen was released following removal of all cannula. The incisions were sutured using silk no. 1 in simple interrupted fashion.

In animals of Group II, Right ovary was hold caudally in the similar way as was done in Group I, the suspensory ligament and associate arteries to ovarian pedicle were cauterised and cut using Karl Storz bipolar electro cautery forceps. Then the left ovary was also separated from suspensory ligament and associated vasculature in similar way. Lastly, by using bipolar electro cautery forceps, the uterine body, artery, and vein proximal to the cervix were grabbed and cauterized (Fig. 6). Ultimately, a side port was used to remove the entire uterine horns and body along with the ovaries (utero-ovarian complex) (Fig. 7 and 8). The skin incisions were sutured with simple interrupted sutures using silk no. 1 (Fig. 9). Surgical wounds were dressed using betadine on alternate days till suture removal on 12th day. Intraoperative and postoperative observations were recorded.

Pain assessment—Post operative observations of pain was made at 2, 8, and 24 hours after surgery based on University of Melbourne Pain Scale (Appendix 1)

The data were subjected to 2-way analysis of variance (ANOVA) and the paired t-test, as per Standard statistical methods.

Ovariohysterectomy was considered procedure of choice for female sterilization, complications such as pyometra, urinary sphincter mechanism incontinence, and weight gain are not seen more commonly with ovariectomy (OVE) versus ovariohysterectomy (OVH) (Okkens et al., 1997; Van Goethem, 2006). Furthermore, some have promoted potential benefits of OVE over OVH including smaller incisions and decreased abdominal trauma, decreased surgery and anaesthesia times (Janssens, 1991; Okkens et al., 1997), smaller celiotomy, and less manipulation of the female genital tract. (Van Goethem, 2006; Van Goethem, 2003; Van Nimwegen, 2005), urinary incontinence was the common complication reported by Okkens et al., (1997), hence it was proved that there was no indication for removing the uterus during routine neutering of healthy bitches, and suggested that ovariectomy should be considered the procedure of choice for neutering and can be a good alternative of OVH. 

The study was conducted on 14 apparently healthy non pregnant animals which were randomly divided into two groups i.e. Group I and Group II. Their body weights ranged from 10.5 to 26 kg (mean-18kg) in Group I and 12kg to 29 kg (mean-19.5kg) in Group II. Age ranged from 12 months to 48 months (mean-28 months) in Group I and 12 months to 42 months (mean- 26.5 months) in Group II. There was no significant difference in the age and body weight between the groups. All the selected animals were nulliparous except the two animals from each group were pluriparous. All the animals were sexually mature in both the groups. All animals of study groups were operated with the same anaesthetic protocol, premedication was done with atropine sulphate and xylazine hydrochloride, induction of anaesthesia was done using ketamine hydrochloride and was maintained using isoflurane gaseous anaesthesia. All the animals had smooth recovery from anaesthesia after surgery.

Total surgical time (mean ± SE) (defined as the time from umbilical incision to skin sutures) was 25.24 ± 1.53 minutes in Group I while it was 36.21 ± 1.56 minutes in Group II. The total surgical time in Group II was significantly (p<0.05) more than that of Group I, similar to the findings reported by Corriveau et al. (2017); which was 67 minutes  for LapOVH and 50 minutes  for LapOVE. Previous reports depicted that mean surgical time for LapOVH recorded by Devitt et al. (2005); Davidson et al. (2004); Mayhew et al. (2007); Austin et al. (2003)  were higher than mean surgical time reported for LapOVE by Manassero et al. (2012); Runge et al. (2012); Case et al. (2011); Dupre et al. (2009). Tapia-Araya et al. (2015); Arntz (2019); Culp (2009) also reported average total surgical time for lap OVE by bipolar electro-cautery i.e. 32.0±3.0 minutes, 22.5 minutes and 30 minutes, respectively. The difference in time is attributed to extra instrument position and handling the tissue at new site at uterine body; extraction of large portion of ovaro-uterine complex instead of only ovaries required extra efforts and time too in lapOVH rather than lap OVE.

Intra-operative complications like mild thermal injury to spleen, bladder was observed in one case of both groups. Spleen puncture occurred during introduction of trocar and veress needle in one case of each Group. Intra-operative haemorrhage occurred during electrocauterization and manipulation of the soft tissue evidenced in one case of Group I and two cases of II. These were also reported by in laparoscopic procedures by Manassero et al. (2012); Dupré et al. (2009); Mayhew et al. (2007); McClaran et al. (2009). Corriveau et al. (2017) reported splenic lacerations in 1.4% cases of their laparoscopic procedures (laparoscopic OVH (1 dog) and OVE (3 dogs)). Malm et al. (2004) reported mild thermal injury and splenic puncture in some of his cases terectomy. Davidson et al., (2004) also reported intra-operative complications like splenic puncture and vaginal discharge. Intra-operative hemorrhage is a common complication in open sterilization surgeries, but it lowered upto 1% as reported by Corriveau et al. (2017). Berzon et al. (1979), reported intraoperative hemorrhage in 20% of dogs in his study on open sterilization technique whereas Burrow et al. (2005), evidenced 6.3% intra-operative hemorrhages in elective OVH. In the present study, the low rate of hemorrhage could support the theory that laparoscopic sterilization reduces the risk for pedicle haemorrhage. Hence, no specific complication was related to one technique so it was proposed that lapOVE is also equally acceptable compared to lapOVH.

Post-operative surgical wound infection including erythema and seroma was reported in aniamls of both Groups, Corriveau et al. (2017), also reported surgical wound infection in 6.7% cases whereas Mayhew et al. (2012) reported wound infection in 1.3% of his cases. Similar findings were reported by Vasseur et al. (1988); Eugster et al. (2004); Beal et al. (2000); Brown et al. (1997).

The mean ± SE values of score (University of melbourne pain scale (UMPS) (Afshar et al., 2017) for post-operative pain at 2nd, 8th and 24th post-operative hours in Group I animals were 2.63±0.83, 2.26±0.29 and 1.43±0.93, respectively, while those in Group II animals were 3.11±0.47, 2.27±0.52 and 1±0.83, respectively. Binder et al. (2018) also studied subjective pain measurements included the recording of behavioural changes and use of different pain scales (simple descriptive scale, four point categorical scale, numeric rating scale, visual analogue scale or several composite pain scales, such as the Glasgow Composite Measure Pain Scale or the University of Melbourne Pain Scale). There was significant difference in pain scores between the Groups at 2 hours. However, there was non-significant difference in pain score between two Groups at 8 and 24 hours. The difference in pain scores could be attributed to the longer time duration in procedure of lapOVH, longer duration of capnoperitoneum which also attributes to pain. Culp (2009); Hancock (2005) also reported that the there was no significant difference in pain score at 24 hours.

LapOVE had advantages like shorter surgical times, and also urinary incontinence recorded was long term post- operative outcome was a common complication, and had no significance with either procedure (LapOVEvsLapOVH).

The present study depicts that both techniques presented same outcomes regardless of animal characteristics. Both LapOVH and LapOVE appeared to be safe and effective methods of surgical sterilization when performed with a multiport or single-port technique (Corriveau, 2017).

Appendix 1- University of melbourne pain scale (UMPS) (Afshar et al., 2017).

Fig. 1. Picture showing Placement of the three port.

Fig. 2. Application of electrocautery forceps at ovarian pedicle and associated blood vessels.

Fig. 3. Resected ovarian pedicle end.

Fig. 4. Electro-cauterisation of uterine horn near ovary in animals of Group I.

Fig. 5. Exteriorised ovaries in animals of Group I.

Fig. 6. Elecrocauterization of uterine body in animals of Group II.

Fig. 7. Exteriorising the uterine horn with ovaries in animals of Group II.

Fig. 8. Exteriorised uterine horn with ovaries in animals of Group II.

Fig. 9. Port site were sutured using silk no. 1 in simple interrupted manner.

Laparoscopic surgery is the new trend introduced in veterinary science, where the regular procedures like sterilisation can be performed with a lot of benefits but still the best technique amongst all techniques is to be declared after the lot of clinical study and data.

Mohan Lal Sharma, S.K. Jhirwal, Mahendra Tanwar and Meena Puniya (2024). Evaluation of Laparoscopic Sterilization Techniques in Dogs. Biological Forum – An International Journal, 16(1): 107-111.