Premedication with acetazolamide: Is its use for postoperative pain and stress control after laparoscopic ovariectomy in dogs ruled out?

BACKGROUND

Studies in human medicine have concluded that acetazolamide reduces pain associated with carbon dioxide insufflation during laparoscopic surgery. However, there are no published reports regarding the use of acetazolamide for this purpose in companion animals, despite the increasing popularity of laparoscopic techniques in veterinary medicine due to their advantages over open surgeries.

OBJECTIVES

Thirty mixed-breed female dogs were included in the study and randomly assigned to one of three groups: OVE (median celiotomy ovariectomy; n = 10), OVEL (laparoscopic ovariectomy, n = 10) and OVELA (laparoscopic ovariectomy with acetazolamide preoperative administration; n = 10). Experienced surgeons performed all procedures, and the anaesthetic and analgesic protocols were identical for all animals. Acetazolamide was administered orally (at a dose of 25 mg/kg) 2 h prior to induction in the OVELA group. Postoperative pain was evaluated using serum cortisol, salivary cortisol, and the University of Melbourne Pain Scale (UMPS) Score.

RESULTS

Any statistical differences were observed in the UMPS scores when the OVELA group was compared to the OVEL group at 1 h after surgery (p = 0.515), 12 h (p = 0.375) and 24 h (p = 0.242). Animals undergoing open surgery (OVE group) had significantly higher pain scores at all times after surgery when compared with OVEL and OVELA groups. A high positive correlation (r = 0.792; p = 0.01) was found between serum and saliva cortisol concentrations. Mean saliva cortisol concentration was not significantly lower for the OVELA group compared to the other groups.

CONCLUSIONS

This study found evidence that preoperative administration of acetazolamide may be beneficial in managing postoperative pain in dogs after laparoscopic surgeries. However, further research with a larger sample size is needed to confirm this and to determine if acetazolamide should be included in a multimodal postoperative analgesia protocol for laparoscopic ovariectomy in dogs.

Evaluation of the Two-Point Ultrasound-Guided Transversus Abdominis Plane Block for Laparoscopic Canine Ovariectomy

The transversus abdominis plane (TAP) block causes desensitization of the abdominal wall and peritoneum. Of all the approaches proposed to perform it, the two-injection-point TAP showed the best results in terms of the area reached by the anesthetic solution. However, to date, no clinical data exist. The aim of this study was to evaluate the intra- and postoperative analgesic efficacy of a two-injection-point TAP block in dogs undergoing laparoscopic ovariectomy. A total of 26 animals were assigned to receive general inhalation anesthesia (control group), and 26 dogs were assigned to general inhalation anesthesia combined with TAP block (TAP group). The ultrasound-guided TAP block was carried out with a subcostal and cranial-to-ilium injection per hemiabdomen. The end-tidal concentration of isoflurane (EtISO) was recorded at different moments during the surgery. Postoperative pain was assessed at different time points during the first 24 h after surgery. The control group required significantly higher EtISO concentration during the ovarian resection and showed higher postoperative pain scores than the TAP group. Fewer dogs in the TAP group required intra- or postoperative rescue analgesia. TAP block can be implemented to improve postoperative pain management after laparoscopy, reducing the dosage of the systemic drugs used and, hence, their possible side effects.

Equine nonneoplastic abnormal ovary in a draft mare with high serum anti-Müllerian hormone: a case study

We performed a standing hand-assisted laparoscopic ovariectomy in a draft mare that presented with high serum anti-Müllerian hormone (AMH) level and had an enlarged single cystic ovary. Histopathological examination revealed no tumor cell proliferation in the ovary, but the presence of a large ovarian cyst was confirmed. In the diagnosis of abnormal ovaries in mares, a comprehensive assessment should be performed, including the monitoring of ovarian morphology and biomarkers over time, to determine the disease prognosis and treatment plan. The case of this mare with a nonneoplastic abnormal ovary and increased serum AMH level was rare. We suggest that standing hand-assisted laparoscopic ovariectomy is useful for the removal of large ovaries in draft mares.

The effect of splash block on the need for analgesia in dogs subjected to video-assisted ovariectomy

Objectives

The present study aimed to demonstrate the efficacy of splash block using lidocaine to provide additional analgesia during ovariectomy in bitches. To identify an acute intraoperative nociceptive response, three clinical parameters were used: increased blood pressure, heart rate and respiratory rate.

Material and Methods

Forty healthy bitches were randomly assigned to receive 2% lidocaine (L group) topical application (splash block) on both ovaries (2 mg/kg each), or an equal volume of NaCl 0.9% at the same sites (C group). A fentanyl bolus (2 µg/kg) was administered intraoperatively in response to an increase in blood pressure, heart rate or respiratory rate during surgery (> 30% compared with the pre‐incisional values).

Results

Local lidocaine administration significantly reduced the need for supplementary fentanyl. Dogs in the L group showed greater intraoperative hemodynamic stability and lower surgical pain than those in the C group. In addition to the routine anaesthetic protocol, the local anaesthesia used in the present study was safe and caused no cardiopulmonary suppression. In addition, it significantly reduced the need for mandatory systemic or rescue analgesia.

Clinical Significance

Ovariectomy is a common surgical procedure in bitches. Analgesia during this procedure is important because intraoperative pain can cause negative effects that prevent patient recovery. This study aimed to demonstrate the analgesic efficacy of lidocaine splash block in video‐assisted ovariectomy in dogs. The results showed that splash block improved surgical analgesia during canine laparoscopic ovariectomy. Considering its relative simplicity, low cost, and safety, splash block could be used in daily clinical practice.

A Comparison of Times Taken for the Placement of the First Portal and Complication Rates between the Veress Needle Technique and the Modified Hasson Technique in Canine Ovariectomy Laparoscopic Surgery

Minimally invasive surgery is increasingly being used in veterinary medicine. Laparoscopic procedures have several advantages compared with open surgery. These include the magnification of the field of surgery, reduced post-surgical pain and associated stress, reduced post-operative infection rates, and decreased hospitalization time. The establishment of a pneumoperitoneum is a critical step; however, this procedure can prolong the operation time, and most of the complications associated with laparoscopic surgery have been attributed to the insertion of devices into the abdominal cavity. Two main techniques have been employed to create pneumoperitoneum: the closed-entry method using the Veress needle and the open Hasson technique. The first portal is necessary to start insufflation and, subsequently, to realize the operative channel to insert the laparoscopic instruments into the abdomen. Many authors have compared the time necessary to create the first portal using different techniques in human medicine, but studies on this topic in veterinary medicine are lacking. In the veterinary medicine literature, complications associated with the creation of a pneumoperitoneum and the placement of ports include spleen, bowel, or bladder injuries; pneumothorax; and subcutaneous emphysema. The aim of the present study was to compare the times required for the placement of the first portal and the creation of pneumoperitoneum, and the rates of intraoperative complications using the Veress needle technique (VNT) and the open modified Hasson technique (MHT). The sample population comprised 30 female dogs who underwent laparoscopic ovariectomies. The dogs were randomly organized into two groups and two different entry techniques were used: Veress needle (VNT = group A) and the modified Hasson technique (MHT = group B). Complications related to abdominal entry were classified as major, in cases of organ perforation, and minor, in cases of subcutaneous emphysema and gas leakage. The VNT and MHT required 374.0 s and 242.9 s, respectively, for the placement of the first portal and for establishing pneumoperitoneum (p < 0.05). Their major complications rates were 20% and 0%, respectively (p < 0.05). Their minor complications rates were 20% and 35%, respectively (p < 0.05). No surgical procedures required laparotomy. The MHT was associated with a lower major complication rate and required less time to create the first portal, compared with the Veress needle technique.

Combined laparoscopic ovariectomy and laparoscopic-assisted gastropexy versus combined laparoscopic ovariectomy and total laparoscopic gastropexy: A comparison of surgical time, complications and postoperative pain in dogs

The trend in laparoscopy is to develop easy and rapid techniques associated with reduced intraoperative complications and decreased postoperative pain. The aim of this study was to compare combined laparoscopic ovariectomy (OIE) and laparoscopic‐assisted incisional gastropexy (LAG) with combined laparoscopic OIE and total laparoscopic gastropexy (TLG) for surgical time, incidence of complications and postoperative pain. Twenty‐eight female dogs were randomly assigned to the LAG group (n = 14) or the TLG group (n = 14). All laparoscopic procedures were performed using a three‐port technique. The gastropexy was located 3 cm caudal to the 13th rib and 4 cm lateral to the rectus abdominis muscle. Surgical time (minutes [min]), intraoperative complications and postoperative complications were recorded. The Glasgow pain score (GPS) (short form) was calculated before surgery and at 1, 6, 12, 18 and 24 hr after extubation. Surgical time was significantly longer in the TLG group (48 ± 2 min) compared with the LAG group (39 ± 2 min). Minor postoperative complications occurred in both groups and included swelling (n = 2) and subcutaneous emphysema (n = 1). No significant differences regarding the GPS were recorded between groups. The GPS was significantly higher in both groups at 1 hr and 6 hr than before surgery. Two dogs in each group required rescue analgesia. Combined laparoscopic OIE and TLG require more time to perform than combined laparoscopic OIE and LAG. Neither procedure results in significant surgical complications. Postoperative pain for 24 hr was mild and comparable in both groups.

Laparoscopic ovariectomy in eastern grey kangaroos (Macropus giganteus) and red kangaroos (Macropus rufus)

OBJECTIVE

To develop a technique for permanent sterilisation of female eastern grey kangaroos (Macropus giganteus) and red kangaroos (M. rufus) as part of a large-scale macropod management program on an enclosed 1545-ha site in western Sydney.

METHODS

Free-ranging female kangaroos (n = 1409: 1285 eastern grey kangaroos, 124 red kangaroos) were anaesthetised via remote anaesthetic drug delivery of tiletamine/zolazepam, medetomidine and acepromazine prior to inhalational anaesthesia using isoflurane-oxygen. A laparoscopic ovariectomy technique was developed using standard laparoscopic equipment to effect permanent sterilisation of the kangaroos. The technique described was also adapted for use on immature animals weighing as little as 1 kg. No direct post-surgical care was provided once the animals had recovered from the anaesthetic.

RESULTS

The procedure was simple to perform and had a very high success rate, with an overall project mortality rate of 2.13% (n = 30). Seven kangaroos (0.05% of all operated kangaroos) were euthanased as a direct result of the surgical procedure. Surgical complications were rare but included inadvertent gastrointestinal tract puncture with the trocar, intraoperative haemorrhage and subcutaneous emphysema leading to pouch eversion following surgery.

CONCLUSION

The procedure described is a rapid and effective method of permanent fertility control in macropods and carries a low mortality rate.