A comparative analysis of opioid-free and opioid-sparing anaesthesia techniques for laparoscopic ovariectomy in healthy dogs

OBJECTIVE

To compare the perioperative analgesic effects of an opioid-free (OFA) and an opioid-sparing (OSA) anaesthetic protocol in dogs undergoing laparoscopic ovariectomy.

STUDY DESIGN

Prospective, randomized, blinded, clinical trial.

ANIMALS

A group of 28 client-owned dogs.

METHODS

Dogs were allocated to one of two groups. The OFA group was administered intramuscular (IM) dexmedetomidine 5 μg kg-1 and ketamine 1 mg kg-1, followed by two intraoperative constant rate infusions (CRIs) of dexmedetomidine (3 μg kg-1 hour-1) and lidocaine (1 mg kg-1 loading dose, 2 mg kg-1 hour-1). The OSA group was administered IM dexmedetomidine 5 μg kg-1, ketamine 1 mg kg-1 and methadone 0.2 mg kg-1, followed by two intraoperative saline CRIs. In both groups, anaesthesia was induced with intravenous (IV) propofol 2 mg kg-1 and diazepam 0.2 mg kg-1 and maintained with isoflurane. Rescue dexmedetomidine (0.5 μg kg-1) was administered IV if there was a 20% increase in cardiovascular variables compared with pre-stimulation values. Ketorolac (0.5 mg kg-1) was administered IV when the surgery ended. Postoperative analgesia was evaluated using the Short Form-Glasgow Composite Measure Pain Scale and methadone (0.2 mg kg-1) was administered IM if the pain score was ≥ 6/24. Statistical analysis included mixed analysis of variance, Chi-square test and Mann-Whitney U test.

RESULTS

There were no significant differences in the intraoperative monitored variables between groups. The OFA group showed a significantly lower intraoperative rescue analgesia requirement (p = 0.016) and lower postoperative pain scores at 3 (p =0.001) and 6 (p < 0.001) hours. No dogs were administered rescue methadone postoperatively.

CONCLUSIONS AND CLINICAL RELEVANCE

Although both groups achieved acceptable postoperative pain scores with no need for further intervention, the analgesic efficacy of the OFA protocol was significantly superior to that of the OSA protocol presented and was associated with a lower intraoperative rescue analgesia requirement and early postoperative pain scores.

Does maropitant provide more effective perioperative pain management than meloxicam in bitches undergoing ovariohysterectomy? The first report on the comparison of visceral algesia-analgesia for ovariohysterectomy

Ovariohysterectomy (OVH) is a widely used surgical procedure in small animal practice. In developing countries, injectable anesthetics such as ketamine and xylazine are commonly used in veterinary medicine. Pharmacological agents with analgesic activity, such as ketamine and meloxicam, are not sufficiently effective in reducing visceral pain. Therefore, this study aimed to investigate the visceral analgesia and anti-inflammatory effectiveness of maropitant compared with those of meloxicam during and after OVH in bitches. In this study, thirty-six bitches were randomly divided into the maropitant, meloxicam, and control groups. The heart rate (HR), peripheral oxygen saturation, and respiratory rate were monitored during the procedure. Pain scores were assessed using the University of Melbourne pain scale (UMPS). Rescue analgesia was not necessary for any bitch at any time point. Blood samples were collected before anesthesia induction and 24 h after the operation to determine C-reactive protein (CRP) levels. No significant difference was observed in HR between the control and meloxicam groups when the right ovary was removed, and the HR of the maropitant group was significantly (p < 0.05) lower than that of the control group. The pain scores of the maropitant group were significantly (p < 0.05) lower than those of the other groups. However, no significant differences were observed in CRP levels between the groups. In conclusion, compared to meloxicam, maropitant provided more effective visceral analgesia in bitches undergoing OVH, although no significant difference was found in its anti-inflammatory effect.

Standing hand-assisted laparoscopic ovariohysterectomy to treat chronic pyometra in a mare

OBJECTIVE

To describe a standing hand-assisted laparoscopic ovariohysterectomy in a mare.

ANIMAL

A 15-year-old maiden Oldenburg mare.

CLINICAL PRESENTATION, PROGRESSION, AND PROCEDURES

The mare was presented for evaluation of bucking under saddle and uncharacteristic aggressive behavior. Evaluation of a 24-hour video of the mare in a stall showed behavior consistent with caudal visceral abdominal discomfort. Reproductive evaluation revealed a pyometra secondary to complete transluminal cervical adhesions. The mare was initially managed medically with disruption of the adhesions and uterine lavage, but the adhesions reformed within 6 weeks and could not be manually disrupted.

TREATMENT AND OUTCOME

To eliminate the recurrence of pyometra, the mare underwent standing hand-assisted laparoscopic ovariohysterectomy through bilateral flank incisions. The only complication was a seroma at 1 flank incision that resolved after drainage.

CLINICAL RELEVANCE

Complete ovariohysterectomy in the mare is a challenging procedure and has previously been performed under general anesthesia. This is the first report of the procedure being performed completely in the standing mare without inversion of the uterus through the cervix.

Evaluation of the analgesic effects of diclofenac as a premedication drug in dogs undergoing ovariohysterectomy

Pre-emptive analgesia consists of administering drugs such as opioids and nonsteroid anti-inflammatory drugs. This study aims to evaluate the intraoperative antinociceptive effects of diclofenac administered alone in premedication or combined with morphine along with its potential influence on recovery of dogs undergoing ovariohysterectomy. A total of 34 dogs (ASA I or II) admitted for ovariohysterectomy were randomly allocated into three groups according to the drugs given in premedication: Diclofenac (D) (n = 11), Morphine (M) (n = 13) and Diclofenac-Morphine (DM) (n = 10) groups. Induction and maintenance of anesthesia were standardized in all dogs. To assess intraoperative nociception, the heart rate (HR) and mean arterial pressure (MAP) were recorded during the surgery and at predefined time points: St (steady-state), Cut (cutaneous incision), P1 (first ovarian manipulation), P2 (second ovarian manipulation) and Cerv (cervical manipulation). The dynamic variation of HR (ΔHR) and MAP (ΔMAP) over 2 min was calculated at each time point. After extubation, early quality of recovery was assessed. Compared to St, a significant increase in HR and MAP at P1, P2 and Cerv was shown in all groups. MAP in the M group was lower at St than in the other groups. The dynamic variation of HR (ΔHR) and MAP (ΔMAP) was significantly less important at P2 and Cerv compared to P1 only in the DM group. Also, a better quality of recovery was shown in the D group compared to the M and DM groups. Diclofenac may be considered a suitable premedication drug and a part of a multimodal anesthetic approach in dogs.

Evaluation of the analgesic efficacy of grapiprant compared with robenacoxib in cats undergoing elective ovariohysterectomy in a prospective, randomized, masked, non-inferiority clinical trial

OBJECTIVES

The main objective of this study was to compare the postoperative analgesic effects of grapiprant with those of robenacoxib in cats undergoing ovariohysterectomy (OVH).

METHODS

In total, 37 female cats (age range 4 months-10 years, weighing ⩾2.5 kg) were enrolled in a prospective, randomized, masked, non-inferiority (NI) clinical trial. Cats received oral robenacoxib (1 mg/kg) or grapiprant (2 mg/kg) 2 h before OVH. Analgesia was assessed via the Feline Grimace Scale (FGS), the Glasgow Composite Measure Pain Scale-Feline (CMPS-F), von Frey monofilaments (vFFs) and pressure algometry (ALG) 2 h before treatment administration, at extubation, and 2, 4, 6, 8, 18 and 24 hours after extubation. Hydromorphone (<8 h postoperatively) or buprenorphine (>18 h postoperatively) were administered to cats with scores of ⩾5/20 on CMPS-F and/or ⩾4/10 on FGS. NI margins for CMPS-F and vFFs were set at 3 and -0.2, respectively. A mixed-effect ANOVA was used for FGS scores (P <0.05). Data are reported as mean ± SEM.

RESULTS

The data from 33 cats were analyzed. The upper limit of the 95% confidence interval (CI) (0.35) was less than the NI margin of 3 for CMPS-F, and the lower limit of the 95% CI (0.055) was greater than the NI margin of -0.2 for vFFs, indicating NI of grapiprant. The FGS scores were greater than baseline at extubation for both treatments (1.65 ± 0.63; P = 0.001); however, there was no difference between treatments. There was no difference between treatments, nor treatment by time interaction, for vFFs (P <0.001). The CMPS-F scores for both treatments were higher at extubation but returned to baseline after 4 h (P <0.001). For ALG, there was no difference in treatment or treatment by time interaction. The robenacoxib group had lower pressure readings at extubation and 6 h compared with baseline.

CONCLUSIONS AND RELEVANCE

These results indicate that grapiprant was non-inferior to robenacoxib for mitigating postsurgical pain in cats after OVH performed via ventral celiotomy. The impact of grapiprant for analgesia in OVH via the flank is unknown.

Advantages of laparoscopic-assisted ovariohysterectomy versus open ovariohysterectomy for dogs with pyometra not detected in randomized clinical trial

OBJECTIVE

To compare results for surgery time, perioperative pain, need for rescue analgesia, variables, serum C-reactive protein concentration, and postoperative complications for dogs with pyometra treated with laparoscopic-assisted ovariohysterectomy (LaOVH) versus open-surgery (OS) ovariohysterectomy.

ANIMALS

12 client-owned dogs with pyometra between June 1, 2016, and December 31, 2019.

METHODS

Dogs enrolled in this prospective single-center randomized clinical trial had pyometra confirmed by history, physical examination, ultrasonography, and blood work and were randomly assigned to treatment group LaOVH or OS. Differences in results for variables of interest were compared between groups using the Mann-Whitney U test, except the number of dogs requiring rescue analgesia was analyzed using the Fisher exact test. Values of P ≤ .05 were considered significant.

RESULTS

6 dogs were recruited in each group; results for 1 dog in the LaOVH group were excluded from further analysis due to free abdominal fluid detected during surgery. Median surgery time was significantly shorter and median total incision length was longer for the OS group (23 minutes; 106 mm), compared to the LaOVH group (37 minutes; 38 mm). No other results differed significantly between groups.

CLINICAL RELEVANCE

Although fewer patients in the LaOVH group required rescue analgesia, this was not statistically significant. Therefore, our results could not prove previously suggested advantages of LaOVH (eg, less perioperative pain or faster recovery) in dogs with pyometra. Additionally, for the LaOVH group, the median surgical time was approximately 50% longer, an assistant was needed, and specialized equipment was required.

Comparison of analgesic efficacy of tramadol, morphine and methadone in cats undergoing ovariohysterectomy

OBJECTIVES

The aim of this study was to compare the analgesic efficacy and the effect on physiological variables and behavior of the use of tramadol, methadone and morphine as preoperative analgesia in healthy cats undergoing elective ovariohysterectomy.

METHODS

Cats undergoing ovariohysterectomy were randomly assigned to receive one of the following premedication treatments intramuscularly: methadone (0.2 mg/kg; n = 10); morphine (0.2 mg/kg; n = 10); or tramadol (3 mg/kg; n = 10). Induction of anesthesia was done with propofol, and maintenance of anesthesia was done with isoflurane. Intraoperative heart rate, arterial blood pressure, respiratory rate, end-tidal isoflurane concentration and frequency of rescue analgesia (fentanyl 2.5 µg/kg) were compared between groups. Postoperative analgesia was assessed using the UNESP-Botucatu Multidimensional Composite Pain Scale, and perioperative serum glucose, cortisol concentrations and postoperative rescue analgesia were evaluated.

RESULTS

Intraoperative rescue analgesia was required in 76.5% of cats at some time during surgery, and 27% of cats required postoperative rescue analgesia up to 6 h after extubation. There were no significant differences between groups with respect to intraoperative and postoperative rescue analgesia, pain scale scores and end-tidal isoflurane concentrations. In the immediate postoperative period, after extubation, most of the patients presented with hypothermia; however, 1-6 h postoperatively, hyperthermia was observed in most of the patients, and was most common in the tramadol group.

CONCLUSIONS AND CLINICAL RELEVANCE

Under the conditions of this study, methadone, morphine and tramadol produced satisfactory postoperative analgesia in most of the cats undergoing ovariohysterectomy, and the effects lasted up to 6 h postoperatively. Intraoperative analgesia was not sufficient in most cases. Significant cardiovascular or respiratory effects contraindicating the use of these drugs were not found. Postanesthetic hyperthermia occurred with all opioids studied and was more frequent in the tramadol group.

Diagnostic value of ultrasonography in identifying unilateral ovarian luteoma in a dog

Background

Diagnosing ovarian tumors in dogs can be challenging since the clinical symptoms are often generic. The present case report underscores a rare case in which a suspected unilateral ovarian tumor in a dog was initially identified using ultrasonography and subsequently confirmed to be a luteoma through postoperative histopathology.

Case Description

An 8-year and 6-month-old female Maltese dog presented with a 10-day history of vulvovaginal bleeding, hematuria, and decreased appetite. Physical examination revealed only vaginal bleeding, with no other abnormalities. Laboratory examinations showed no abnormalities, while abdominal radiography revealed the presence of cystic calculi as the sole abnormality. Abdominal ultrasound revealed an enlarged right ovary with regular contour and echogenicity, featuring unusual cystic components surrounding the right ovarian parenchyma. Furthermore, irregular thickening with multiple cystic lesions was observed in the endometrial wall of the bilateral uterine horns, indicative of cystic endometrial hyperplasia. Ultrasonographic findings suggested unilateral right ovarian disease. During ovariohysterectomy, the right ovary was slightly larger than the left ovary and adhered to the surrounding mesenteric fat layer and right pancreatic parenchyma. Histopathological examination confirmed the diagnosis of luteoma in the right ovary. Three days after surgery, the patient's clinical signs exhibited complete improvement, with the return of normal appetite.

Conclusion

This case report highlights a rare diagnosis of unilateral ovarian luteoma based on mild ultrasonographic abnormalities, which was ultimately confirmed on histopathological examination.

Applying children's enuresis treatment with amitriptyline for canine post-spaying urinary incontinence: A pilot estriol-controlled randomized clinical trial

Urinary incontinence due to urethral sphincter mechanism incompetence (USMI) affects up to 20% of bitches that undergo spaying surgery. Amitriptyline is a tricyclic antidepressant whose urinary retention is a reported side effect. This study aimed to assess the efficacy and safety of amitriptyline when compared to estriol orally. Fifteen bitches with a clinical diagnosis of post-spaying UI were evaluated during 60 days in a non-blinded randomized clinical trial. All patients were enrolled after clinical evaluation consisting of anamnesis, physical examination, and complementary exams (complete blood count, biochemical parameters, urinalysis, and abdominal ultrasound). The amitriptyline (AMT) group consisted of 8 bitches, which received the initial dose of 1 mg/kg every 12 h, whereas the estriol (EST) group consisted of 7 bitches which were initially treated with 1 mg/animal every 24 h. Patients underwent clinical evaluation at 7 days, and then at 21 and 60 days of treatment to assess safety and efficacy, as well as adjustments of dose when necessary. A urinary incontinence scale was used to assess the level of incontinence and therapeutic response to treatment. During the period of the study, estriol was fully effective in 71% of cases and amitriptyline in 62%. Both drugs proved safe in the medical treatment of USMI, with adverse effects such as somnolence (AMT, n = 5/8) and male attraction (EST, n = 1/7). The results support the amitriptyline recommendation as a substitute for estriol in USMI treatment.

Evaluation of lidocaine administration into the ovarian pedicle for the control of intraoperative and early postoperative pain during ovariohysterectomy in dogs

OBJECTIVE

To evaluate effects of lidocaine 2% administration into the ovarian pedicle on intraoperative nociception and early postoperative pain in dogs undergoing ovariohysterectomy.

STUDY DESIGN

Prospective, randomized, blinded clinical study.

ANIMALS

A total of 20 healthy adult female dogs of different breeds.

METHODS

Dogs were premedicated with acepromazine (0.02 mg kg-1) and morphine (0.5 mg kg-1) intramuscularly, anesthesia induced with propofol and maintained with isoflurane. Dogs were randomly assigned to be administered 2 mL of saline (group S) or lidocaine 2% (group L) into the mesovarium (1 mL each side). Heart rate (HR) and noninvasive systemic arterial pressure were recorded before surgery (T0), before (T1) and during ligation of the right ovarian pedicle (T2), before (T3) and during ligation of the left ovarian pedicle (T4). Rescue treatment (propofol) was administered if HR or systolic arterial pressure (SAP) increased by 20% compared with the previous time point. Pain, assessed with the Glasgow Composite Measure Pain Scale-Short Form (CMPS-SF) was recorded before premedication (baseline) and after extubation. Administration of postoperative rescue analgesia was recorded.

RESULTS

In group S, HR was higher at T2 than T1 (112 ± 18 versus 89 ± 21 beats minute-1, p = 0.001) There were no significant differences between treatments at any time. SAP was higher at T2 than T1 in group S (110 ± 12 versus 100 ± 10 mmHg, p = 0.031). SAP was higher in group S than group L at T3 (113 ± 12 and 91 ± 10 mmHg, respectively, p = 0.001). No dogs required propofol intraoperatively. All dogs required postoperative rescue analgesia. Compared with baseline, CMPS-SF increased 60 minutes after extubation (group S; p = 0.019, group L; p = 0.043).

CONCLUSIONS AND CLINICAL RELEVANCE

Administration of lidocaine 2% into the mesovarium did not reduce intraoperative nociception and did not improve postoperative analgesia.

Comparison of two advanced bipolar tissue sealer/dividers for laparoscopic ovariectomy in dogs: articulating enseal G2 versus Ligasure Maryland device

BACKGROUND

Advanced bipolar tissue sealer/dividers provide the most reliable and efficient means of tissue dissection and blood vessel sealing in laparoscopic surgery and the techniques are continuously improved. In veterinary practice, cost-effectiveness is of major impact, leading to re-use of instruments designed and sold for single use. Two high-end devices were evaluated and compared in a highly standardized laparoscopic ovariectomy procedure in dogs: The new generation Ligasure Maryland Sealer/Divider (LMSD) with improved atraumatic curved jaw shape for delicate tissue handling and dissection and non-stick nanocoating, and the new-generation Articulating Enseal G2 (AENG2) with several proclaimed features improving surgical performance, including articulation of the forceps tip; improved tissue compression during sealing; unique offset electrode configuration; and specific nanoparticle coating minimizing thermal spread and tissue sticking. Twenty-one client-owned dogs admitted for elective laparoscopic ovariectomy were randomly assigned to one of two groups: ovariectomy using AENG2 on the left ovary and LMSD in the right ovary or vice-versa. Procedural video recordings were used to assess ovarian ligament fat score, smoke formation, occurrence of bleeding, and excision duration. Excised tissues were examined histopathologically and collateral thermal damage was scored in three anatomic zones: suspensory ligament, vascular pedicle, and uterine junction. Tissue sealers were used repeatedly following standardized cleaning protocol with instrument washing machine and ethylene oxide gas sterilization and the number of uses until device failure was recorded.

RESULTS

Excision times were significantly increased for AENG2 (median 01:35 min) compared to LMSD (median 01:00 min). Minor hemorrhage from incomplete sealing occurred in 3 sites in 2 patients (2x AENG2, 1x LMSD) and was not significantly different between groups. Smoke production as scored on videos and thermal tissue damage scores on histopathology also did not differ between AENG2 and LMSD. Both vessel sealers could be re-used repeatedly.

CONCLUSION

AENG2 provides a good alternative to LMSD in laparoscopic ovariectomy, with only minor differences in measured variables. Subjectively, the articulating feature of AENG2 did not improve surgical performance in laparoscopic ovariectomy and the use of LMSD appeared more straight-forward for this specific procedure. However, differences in operating these devices may be subject to personal preference.

A liposomal bupivacaine infiltrative block reduces rescue analgesia administration compared to a bupivacaine splash block after canine ovariohysterectomy in a teaching laboratory

OBJECTIVE

This study aimed to determine whether an infiltrative block with liposomal bupivacaine was associated with less rescue analgesia administration and lower pain scores than a bupivacaine splash block after ovariohysterectomy in dogs.

ANIMALS

Eligible dogs included those that were spayed as part of a veterinary teaching laboratory. Dogs were up to 7 years old and otherwise healthy. A total of 136 dogs were analyzed.

METHODS

All dogs underwent ovariohysterectomy performed by veterinary students. Dogs received hydromorphone and acepromazine premedication, propofol induction, isoflurane maintenance, and an NSAID. Dogs were randomly allocated to receive either a splash block with standard bupivacaine or an infiltrative block with liposomal bupivacaine for incisional analgesia. Postoperatively, all dogs were assessed by a blinded evaluator using the Colorado State University-Canine Acute Pain Scale (CSU-CAPS) and Glasgow Composite Measures Pain Scale-Short Form (GCPS-SF). Dogs received rescue analgesia with buprenorphine if they scored ≥ 2 on the CSU-CAPS scale.

RESULTS

Dogs that received liposomal bupivacaine had a significantly lower incidence of (P = .04) and longer time to (P = .03) administration of rescue analgesia. There was an overall time-averaged significant difference between groups for CSU-CAPS (P = .049) and GCPS-SF scores (P = .015), with dogs in the bupivacaine group being more likely to have an elevated pain score at some point for both scales.

CLINICAL RELEVANCE

The use of liposomal bupivacaine in an infiltrative block may decrease the need for rescue analgesia in dogs undergoing ovariohysterectomy compared to a bupivacaine splash block.

Robenacoxib versus meloxicam following ovariohysterectomy in cats: A randomised, prospective clinical trial involving owner-based assessment of pain

BACKGROUND

Injectable non-steroidal anti-inflammatory drugs (NSAIDs) are commonly prescribed to queens undergoing ovariohysterectomy (OVH), but the requirement for postoperative administration is unclear and practices vary. Existing studies assessing efficacy rely on pain scoring by experienced clinicians. However, following OVH, most cats are discharged within hours of recovery.

METHODS

Cats undergoing OVH were randomly assigned to two treatment groups: MEL and ROB. Cats in the MEL group (n = 76) received meloxicam (0.2 mg/kg) and those in the ROB group (n = 65) received robenacoxib (2 mg/kg). Owners were contacted by a blinded assessor 3 days postoperatively and asked to identify physical or behavioural changes and to assign pain scores using a numerical rating scale.

RESULTS

More cats in the ROB group displayed abnormal behaviours than cats in the MEL group (p = 0.03). Most owners assigned a pain score of 0 (72%) (n = 101), but pain scores were significantly higher in the ROB group than in the MEL group (p = 0.005).

LIMITATION

Methods of owner assessment of pain in cats have not been validated.

CONCLUSIONS

Both meloxicam and robenacoxib are effective in controlling postoperative pain. Meloxicam may have improved efficacy in certain patient populations. Applying a blanket approach to prescribing NSAIDs to cats undergoing OVH postoperatively may not be necessary. This has safety, environmental and cost implications.

Intraperitoneal and incisional ropivacaine did not improve postoperative analgesia after multimodal anaesthesia compared with saline in dogs undergoing ovariohysterectomy

INTRODUCTION

Intraperitoneal administration of local anaesthetics may reduce postoperative pain after ovariohysterectomy in dogs. The aim of this prospective, randomised, blinded, placebo-controlled clinical trial was to compare postoperative analgesia and opioid requirements after intraperitoneal and incisional administration of ropivacaine versus 0,9 % NaCl (saline). Forty-three client-owned dogs were enrolled in the study and anaesthetised using a standardized protocol that included premedication with acepromazine (0,03-0,05 mg/kg) and dexmedetomidine (0,01 mg/kg) intramuscularly. Anaesthesia was induced with propofol titrated to effect and ketamine (1 mg/kg) intravenously and maintained with isoflurane in oxygen. The analgesic regimen included carprofen (4 mg/kg) subcutaneously and morphine (0,2 mg/kg) intravenously. Depending on group assignment, each dog received either an intraperitoneal and incisional splash with ropivacaine (2 mg/kg and 1 mg/kg, respectively) (group R), or an equal volume of saline (group S). Buprenorphine (0,02 mg/kg) was administered intramuscularly once the uterus was removed. Sedation and pain were assessed 0,5, 1, 2, 4, 6 and 8 hours after extubation using a sedation scale, the short form of the Glasgow Composite Pain Scale (CMPS-SF) and a dynamic interactive visual analogue scale (DIVAS). Postoperatively, buprenorphine (0,01 mg/kg) was administered intravenously if dogs scored 6/24 on CMPS-SF. The ordinal mixed model showed no difference in pain scores between groups. Fisher's exact test showed no significant difference in postoperative buprenorphine requirements between group S (3/22 dogs) and group R (1/21 dogs) at the doses used. In addition, lower sedation scores were associated with higher DIVAS scores. In this multimodal analgesic protocol, ropivacaine could not improve analgesia compared to saline.

A vessel sealing device and an ultrasonic dissector are equally effective and safe for single port laparoscopic ovariectomy in dogs

OBJECTIVE

To evaluate ovary removal surgery times and intraoperative complication rates between a 5-mm Sonicision cordless ultrasonic dissector (SCUD) and 5-mm vessel sealing device (VSD) for laparoscopic ovariectomy in dogs.

ANIMALS

Client-owned, intact female dogs (n = 10) presented for elective laparoscopic ovariectomy.

METHODS

In each dog, 1 ovarian pedicle was randomly assigned to the SCUD group and 1 to the VSD group. In the SCUD group (n = 10), the ovariectomy was performed using the SCUD device; the ovariectomy in the VSD group (10) was performed using a VSD. The number of applications of each device during ovariectomy, surgery time required for each ovary removal, total surgery duration, ovarian pedicle fat score, and intraoperative complications were recorded.

RESULTS

Both left and right ovaries had median pedicle fat scores of 2 (range, 1 to 3). To complete an ovariectomy, the median number of SCUD applications was 9 (range, 7 to 13) times; the VSD had a median of 10 (range, 5 to 18) times (P = .98). Median surgery times for the removal of 1 ovary with the SCUD and VSD were 96 seconds (range, 45 to 417 seconds) and 110 seconds (range, 42 to 164 seconds), respectively (P = 1). No intraoperative complications were associated with either device. Therefore, the VSD was not required for rescue in the SCUD group, and no conversions to open ovariectomy were necessary.

CLINICAL RELEVANCE

A standard approach laparoscopic ovariectomy performed with the SCUD was successful in our population of dogs, making the 5-mm SCUD safe for laparoscopic ovariectomy in healthy dogs, which provides a more affordable option for practitioners and clients.

Bromelain does not provide significant analgesic and anti-inflammatory benefits over placebo in cats undergoing ovariohysterectomy

OBJECTIVE

To evaluate the efficacy and safety of bromelain to control pain and inflammation in cats undergoing ovariohysterectomy.

ANIMALS

30 client-owned cats undergoing ovariohysterectomy.

PROCEDURES

In a randomized, blinded clinical study, cats were assigned to receive either oral bromelain suspension (40 mg/kg [18 mg/lb]; BG, n = 15) or placebo solution (0.1 mL/kg [0.045 mL/lb]; PG, 15), which were administered 90 minutes before and 12 hours after surgery. The anesthetic protocol included acepromazine, meperidine, propofol, and isoflurane. Pain and sedation were assessed at various time points up to 24 hours post-extubation using the UNESP-Botucatu multidimensional composite pain scale, the Glasgow feline composite measure pain scale, and a descriptive numerical scale. Surgical wound inflammation was measured at the same time points, using a numeric rating scale. Morphine was administered as rescue analgesia. Laboratory data (urea, creatinine, gamma-glutamyl transferase, alkaline phosphatase, the prothrombin time, and the fecal occult blood) were analyzed preoperatively and 24 hours after surgery.

RESULTS

Pain/inflammation scores, and analgesic requirements did not differ between groups. Shorter recovery time and lower sedation scores were recorded during the first hour post-extubation in the BG than the PG. Postoperatively, serum creatinine and gamma-glutamyl transferase were lower in the BG compared to PG. Compared to baseline values, all biochemistry variables decreased at 24 hours in the BG. The prothrombin time and fecal occult blood did not differ between groups or over time.

CLINICAL RELEVANCE

Bromelain did not provide significant analgesic and anti-inflammatory benefits over placebo in cats undergoing ovariohysterectomy.

Liposomal bupivacaine is both safe and effective when administered via local infiltration at surgical site and mesovarium for laparoscopic ovariectomy in mares

BACKGROUND

Liposomal local anaesthetic solutions may provide extended-duration analgesia postoperatively but have not been assessed following intra-peritoneal local infiltration in any species.

OBJECTIVES

To evaluate two doses of 1.33% liposomal bupivacaine (LB) versus 0.75% bupivacaine HCL (BHCl) for analgesia following laparoscopic ovariectomy in mares.

STUDY DESIGN

Prospective cohort study.

METHODS

Fifteen healthy Quarter Horse mares (age 2-20 years) with normal bilateral ovarian palpation and appearance were enrolled. Horses were restrained in standing stocks and administered an α-2 agonist, butorphanol, and flunixin meglumine, followed by a variable rate infusion of sedation with α-2 agonists. Bilateral paralumbar fossa ovariectomies were performed. Treatment with either 30 ml 0.75% BHCl followed by 20 or 40 ml LB 13.3% (LB20 and LB40) volume expanded with saline to 80 ml total (n = 6/group) or 80 ml BHCl alone (n = 3, BCHL) was infused around incision sites and each mesovarium (LB or BHCl) prior to ovariectomy. Horses were monitored for 72 h by physical examination, algometry, and pain scoring (composite pain scale by Bussieres et al., Horse Grimace Scale). Abdominocentesis with peritoneal fluid analysis was performed at 72 h.

RESULTS

Analgesia achieved with all treatment protocols allowed completion of ovariectomy procedures. Pressure algometry scores were lower in BHCl-treated horses versus both LB groups overall. Pain scores were improved with LB-treated horses in a dose-dependent fashion (Horse Grimace Scale scores LB40 < LB20 < BHCL; composite pain scale scores LB40 < BHCL, LB20 < BHCL, BHCL, and LB20 did not differ). Peritoneal fluid total protein was lower in LB40 versus LB20 and BHCL horses. No complications from LB administration were appreciated.

MAIN LIMITATIONS

Small patient sample size, lack of follow-up past 72 h or histopathology.

CONCLUSIONS

Analgesia duration was extended and pain scores improved postoperatively with LB versus BHCl in a dose-dependent fashion. Further clinical evaluation of extended-duration local anaesthetics in horses for improved postoperative pain management is warranted.

Influence of the Dose and Frequency of Administration of Tramadol on Analgesia, Hematological, Biochemical Parameters, and Oxidative Status of Cats Undergoing Ovariohysterectomy

This study aimed to evaluate the effects of the repeated administration of tramadol subcutaneously on postoperative analgesia, liver, kidneys, and oxidative status in the postoperative period of cats undergoing ovariohysterectomy. Thirty-seven cats were randomly assigned to 5 groups, according to the postoperative analgesic treatment: NaCl 0.9%, GC; tramadol at 2 mg/kg, T2B (q12h) and T2T (q8h); or 4 mg/kg, T4B (q12h) and T4T (q8h). Oxidative status was assessed at baseline, 12 hours and 24 hours after the final administration of tramadol by the activity of superoxide dismutase (SOD), catalase (CAT), myeloperoxidase (MPO), butyrylcholinesterase (BuChE), and lipoperoxidation (MDA). Total blood count, serum biochemistry and urinalysis were compared between baseline and 12 hours posttramadol. Postoperative pain was evaluated by applying the Glasgow Feline Composite Measure Pain Scale at baseline, 3 (T3), 6 (T6), 8 (T8), 12 (T12), 24 (T24) e 36 (T36) hours after extubation. No side effects were observed. Tramadol increased SOD activity while CAT varied among groups in all time points but not over time. MDA levels increased from baseline to 12 hours in all groups but T4T. MPO activity decreased from baseline to 24 hours in some groups, including GC. Creatinine and phosphatase alkaline decreased in T2T, T4B, and T4T at 12 hours. Higher pain scores were observed from T3 to T8, except for GC. Rescue analgesia was administered only at T3. No difference in pain scores was observed from T8 onwards. Based on the findings, it is suggested that tramadol at 2 mg/kg every 8 hours is recommended for postoperative analgesia of cats undergoing ovariohysterectomy.

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.

Comparison of conventional ligatures and a vessel sealing device for haemostasis during open ovariohysterectomy in rabbits

AIMS

To compare surgical times and rates of intra-operative and post-operative complications for open ovariohysterectomy (OVH) in female rabbits using conventional ligatures or a vessel sealing device (VSD) for haemostasis.

METHODS

Female pet rabbits (n = 23) presented for OVH for either desexing or treatment of reproductive disorders were randomly assigned to a conventional ligatures (CL) group (n = 12) or a LigaSure 5-mm (LS5) group (n = 11). In the CL group, the ovarian pedicles were ligated with a single surgeon's knot. After transection of the ovarian pedicles, the broad ligament was manually broken down along the uterine horns to their respective cervices. In the LS5 group, both ovarian pedicles and the broad ligaments were sealed with a LigaSure Dolphin Tip VSD with 5-mm forceps. All the rabbits were hospitalised for 24 hours after surgery. Two weeks after discharge, a clinical recheck examination was performed. Incision length, overall surgical time (from initial incision to completion of intradermal suturing), OVH time (from identification of the first ovary to transection of the vaginal vault), and intra- and post-operative complications were recorded and compared between groups, using the Student's t-test for normally distributed continuous data, the Wilcoxon-Mann-Whitney test for non-normally distributed continuous data and Pearson's χ2 test for categorical data.

RESULTS

The mean overall surgical time was 14.1 (SD 4.4) minutes. The surgery took 15.0 (SD 4.9) minutes in the CL group and 13.1 (SD 3.8) minutes in the LS5 group (p=0.10). The OVH time was shorter in the LS5 group (mean 4.2 (SD 0.9) minutes) than in the CL group (mean 6.3 (SD 1.7) minutes; p = 0.005). No intra-operative complications were encountered in the LS5 group. Haemorrhage occurred in three rabbits in the CL group. One rabbit in the LS5 group developed steatonecrosis post-operatively. There was no evidence of a difference in the proportion of rabbits that experienced intra- and post-operative complications (p = 0.25 and p = 0.94 respectively) between groups.

CONCLUSIONS

The use of a LigaSure 5-mm VSD and conventional ligatures during open OVH were both associated with similar overall surgical times and complication rates. The OVH times were shorter in the LS5 group compared to the CL group.

CLINICAL RELEVANCE

Use of the LigaSure 5-mm VSD allows efficient haemostasis while performing open OVH in female pet rabbits.

Postoperative Acupuncture is as Effective as Preoperative Acupuncture or Meloxicam in Dogs Undergoing Ovariohysterectomy: a Blind Randomized Study

Background

Acupuncture has the same analgesic effect as non-steroidal antiinflammatory drugs and opioids. It is challenging to perform preoperative acupuncture in unmanageable animals, while the residual postoperative anesthetic effect facilitates the performance of acupuncture postoperatively.

Objectives

To compare preoperative acupuncture or meloxicam versus postoperative acupuncture for postoperative analgesia after ovariohysterectomy.

Methods

This is a horizontal prospective positive control blind randomized experimental study. Thirty-six dogs were randomly divided into three groups: GA (preemptive acupuncture), GPA (postoperative acupuncture), and GM (meloxicam 0.2 mg/kg IV preoperatively). After sedation with acepromazine (0.05 mg/kg IM), anesthesia was induced with propofol (5.3 ± 0.3 mg/kg) and maintained with isoflurane/O2. Fentanyl (2 μg/kg, IV) was administered immediately before surgery. Bilateral acupuncture was performed at acupoints Large intestine 4, Spleen 6, and Stomach 36 for 20 minutes, before (GA) or immediately after surgery (GPA). Pain was evaluated by an observer blind to the treatment using the Glasgow scale before and for 24 hours after ovariohysterectomy. Dogs with a score ≥ 6 received rescue analgesia with morphine (0.5 mg/kg IM). Nonparametric data were analyzed by the Kruskal-Wallis test, followed by Dunn's test and parametric data by ANOVA followed by Tukey's test.

Results

Two GA and one GPA dogs received rescue analgesia once. Two GM dogs received rescue analgesia and one of those was treated again twice. There were no differences in the number of dogs receiving rescue analgesia between groups (p = 0.80).

Conclusion

Postoperative acupuncture was as effective as preoperative acupuncture or meloxicam in female dogs undergoing ovariohysterectomy.

Perioperative Analgesic Efficacy of Yamamoto New Scalp Acupuncture for Canine Mastectomy Combined with Ovariohysterectomy: a Randomized, Controlled Clinical Trial

Background

Yamamoto New Scalp Acupuncture (YNSA) is a therapy based on the stimulation of points on the scalp and applied to treat different states of pain.

Objectives

To investigate the analgesic efficacy of YNSA for dogs undergoing radical unilateral mastectomy with ovariohysterectomy.

Methods

Twenty-four dogs were randomly distributed into two treatments (n = 12, per group): bilateral stimulation of basic B, D, and E points (YNSA group) and no application of acupuncture (control group). All dogs were sedated with morphine; anesthesia was induced with propofol and maintained with isoflurane. Fentanyl was intraoperatively administered to control cardiovascular responses to surgical stimulation. Postoperative pain was assessed using an interactive visual analog scale (IVAS) and the short-form of the Glasgow Composite Pain Scale (CMPS-SF). Morphine was administered as rescue analgesia. Data were analyzed using t-tests, Fisher's exact test, Mann-Whitney U test, and Friedman test (p < 0.05).

Results

Intraoperatively, the number of dogs requiring supplemental analgesic and the number of doses of fentanyl were lower in the YNSA group than in the control group (p = 0.027-0.034). The IVAS pain scores recorded from 0.5 h to 1 h post-extubation in the YNSA group were lower than those in the control group (p = 0.021-0.023). Postoperative rescue analgesia and CMPS-SF pain scores did not differ between the groups.

Conclusion

YNSA decreases intraoperative fentanyl requirements and provides minimal postoperative analgesic benefits to dogs undergoing unilateral mastectomy with ovariohysterectomy.

Laparoscopic ovariectomy in a dog with type III sclerosing encapsulating peritonitis and literature review

Sclerosing encapsulating peritonitis is a rare and not well-recognized disease in veterinary medicine. A 14-month-old female intact mixed-breed dog was diagnosed with sclerosing encapsulating peritonitis (SEP) at the age of 5 months after a routine work-up including biopsies from an exploratory laparotomy. Symptomatic treatment with an immunosuppressive dose of prednisolone was started, but dose reduction was unsuccessful. Combined treatment with tamoxifen, a selective estrogen receptor modulator used for its TGF-β1 suppression of fibroblasts was discussed; the owner was informed about the risk for developing a pyometra. About one year later the owner wanted to spay her dog and an ovariectomy was recommended, especially due to the extensive adhesions. A laparoscopic approach was chosen to reduce the amount of intraoperative tissue manipulation and inflammation, as well as to minimize the size of the incision. The dog continues to be doing well one year after surgery and prednisolone could be reduced to a low maintenance dose after surgery; so far, the addition of tamoxifen was not required. In selected cases, laparoscopy appears as a safe alternative in patients with adhesions, but the surgeon should always be prepared to convert in case of impaired vision, especially in the absence of tactile sensation. This case report is the first description of laparoscopy in a dog with SEP. Laparoscopy may serve as an easily accomplished minimally invasive method to diagnose SEP, but further studies are required.

Preliminary results of blood growth differentiation factor-9 (GDF-9) measurement in cats: future aspects of GDF-9 on stage of the cycle and spaying history

Growth differentiation factor-9 (GDF-9), an oocyte-derived member of the TGF-β superfamily, plays an essential role in regulation of follicular development. This study aimed to determine the cyclic changes in serum GDF-9 concentration, compare its levels before and after ovariohysterectomy (OHE), and investigate its potential as a tool in ovarian remnant syndrome (ORS) diagnosis in cats. GDF-9 measurements were performed on 50 cats referred for routine OHE. The stage of the estrous cycle was determined by vaginal cytology and measurement of serum estradiol and progesterone levels was carried out to detect the cyclic changes in circulating GDF-9. One week after OHE, serum samples were collected again from 30 cats to reveal differences in GDF-9 levels. GDF-9 levels in the follicular phase were significantly higher than those in the interestrus (p⟨0.05). The postoperative analysis could be performed. GDF-9 levels slightly decreased one week after OHE (p=0.053). In conclusion, blood GDF-9 levels change during the estrous cycle, and may decrease with age in cats. However, further studies are needed to reveal the efficiency of GDF-9 in ORS diagnosis.

Left lateral flank approach for spaying in cats

Background: Spaying is considered as a reliable surgical method for birth control and preventing potential feline reproductive diseases. Aim: This experiment was carried out to evaluate the suitability of left lateral flank approach for routine spaying in cats. Methods: Twenty-seven queens of 7-24 months old and 1.5-3.5 kg BW were spayed through flank laparotomy in the left lateral side of abdomen. The cats were categorized into two groups: Group A (n=12; cats did not yet give birth) and Group B (n=15; cats gave birth before). The studied variables included age, BW, vaccination history, skin incision length, total surgical duration, time needed for ligating ovarian pedicles and uterine body, suture materials, postoperative complications and healing duration. Results: There were no significant differences (P<0.05) in age, BW and vaccination history of the cats between the two groups. The mean incision length and total duration of surgery were greater in case of Group B than Group A. The ease of entering into the peritoneal cavity, duration of ligating the ovarian pedicles and transfixing the uterine body did not vary significantly (P<0.05) between the groups, although longer time was taken for Group B than Group A. 62.96% spayed cats were found with no postoperative complication. The observed complications included wound site infection (7.41%), dehiscence of suture lines (11.11%), bleeding (3.70%) and oozing (14.82%) from wounds which were further treated successfully for complete recovery. Conclusion: Left lateral flank approach can be an effective method of spaying in queens without any life threating complication.

Comparison of Hemorrhagic Complications with Double-ligated versus Auto-ligated Feline Ovarian Pedicles by Fourth-Year Veterinary Students

The objective of this article is to compare the occurrence of hemorrhagic complications in student-performed feline ovarian pedicle ligations using the traditional suture pedicle double-ligation (PDL) to the suture-less auto-ligation (AL) techniques, and to describe the stepwise method of teaching the AL technique to students. A total of 287 cats underwent an ovariohysterectomy (OHE) performed by a fourth-year veterinary student trained by veterinary faculty to perform the AL technique beginning with a low-fidelity model and progressing to live patient surgeries. Students performed the AL and PDL techniques on 146 and 141 cats respectively. Hemorrhagic complications occurred in 4 of 146 cats (2.7%) in the AL group and 8 of 141 (5.7%) in the PDL group and were not found to be significantly different (p = 0.2496). This article demonstrates that novice surgeons can safely perform the AL technique on feline ovarian pedicles without significantly increasing complications compared to the traditionally taught method when a stepwise training program is implemented. Additionally, this technique has been shown to be safe, effective, and more efficient when performed by experienced veterinary surgeons.¹ Veterinary institutions should consider including the AL technique in their core curricula as a standard method for feline ovarian pedicle ligation. Doing so will facilitate the development of more proficient entry-level practitioners who are better able to serve their patients, clients, employers, humane societies, and their communities by using a more efficient and safe feline ovariohysterectomy technique.

Evaluation of intraperitoneal administration of morphine on post-operative pain management after ovariohysterectomy in dogs

The present prospective randomized experimental study was designed to assess pain control with intraperitoneal morphine following ovariohysterectomy in dogs. A group of 12 mixed breed female dogs, aged 1-2 years, weighing 19.95 ± 0.95 kg were included. Forty minutes after sedation with 0.05 mg/kg intramuscular acepromazine 1%, anaesthesia was induced with propofol (4 mg/kg). The dogs were connected to the inhalation anaesthesia circuit using isoflurane. Ovariohysterectomy was performed, and before the closure of linea alba, the animals received intraperitoneal morphine (0.5 mg/kg) (in group M) and saline (0.2 ml/kg) (in group S). No significant difference was detected in total protein and glucose levels between the groups, while the cortisol level in group M was significantly lower than group S 1, 3 and 6 h after surgery. Furthermore, the comparison of the rectal temperature, heart rates and respiratory rates showed no major differences. Additionally, no significant alterations were detected between the groups considering the changes in the pain scores with simple descriptive score, Glasgow, University of Melbourne pain scale, sedation status and Sammarco methods. Finally, three cases in group S and two cases in group M were given an intramuscular analgesic rescue dose of morphine. Although a significant decline was observed in cortisol levels following intraperitoneal morphine administration, there were no beneficial changes in the efficiency of post-operative analgesia in status and clinical signs compared to the control group. Further studies are required to investigate intraperitoneal morphine effectiveness in post-operative pain management.

Combined laparoscopic ovariectomy and laparoscopic-assisted gastropexy utilizing a 2-port technique in 10 dogs

A case series was selected retrospectively to evaluate the technique, outcome, and short-term complications associated with a combined laparoscopic ovariectomy (Lap OVX) and laparoscopic-assisted gastropexy (LAG) using a 2-port technique, and to compare it with previously published combined laparoscopic techniques for Lap OVX and LAG in dogs. Medical records of dogs undergoing elective, combined Lap OVX and LAG performed using a 2-port technique between 2017 and 2019 were reviewed. Total surgical time was compared to previously published combined Lap OVX and LAG techniques in dogs. Intraoperative and short-term complications were recorded. Ten dogs [median weight: 29.4 kg (range: 11.4 to 84.1 kg); mean: 37.4] met the inclusion criteria. Median surgical time to complete both the Lap OVX and LAG was 72.5 minutes (range: 47.0 to 120.0 minutes; mean: 77.4 minutes), which was not significantly different than that described in previous studies of combined Lap OVX and LAG (weighted mean average: 67.3 minutes; 95% confidence interval: 46.9 to 87.7, P = 0.3). No intraoperative or postoperative complications were reported. It is concluded that a 2-port technique for combined Lap OVX and LAG is feasible, has few complications, and requires similar time to perform compared to other previously published laparoscopic techniques.

The analgesic and sedative effects of GV20 pharmacopuncture with low-dose hydromorphone in healthy dogs undergoing ovariohysterectomy

This study evaluates the analgesic efficacy of low-dose hydromorphone administered via pharmacopuncture at Governing Vessel 20 (GV20) for postoperative pain management following canine ovariohysterectomy. Fifty clinically healthy female dogs undergoing ovariohysterectomy were allocated to receive hydromorphone [0.1 mg/kg body weight (BW)] intramuscularly (IM, n = 25) or hydromorphone (0.01 mg/kg BW) pharmacopuncture at GV20 (GV, n = 25) following extubation. This was a prospective, blinded, randomized clinical trial. Pain and sedation scores were evaluated using the Glasgow Composite Measure Pain Scale Short Form (CMPS-SF) at 1, 2, 3, 4, and 12 hours following study treatment. Time of treatment failure (CMPS-SF ≥ 6/24) was recorded and analyzed using Kaplan-Meier survival analysis. Patient demographics and duration of surgery and anesthesia were analyzed using the appropriate unpaired Student's t-test. The Glasgow CMPS-SF and sedation score were analyzed using a repeated measures 2-way analysis of variance (ANOVA) followed by Bonferroni post-test where appropriate. Significance was set a P < 0.05. There were no significant differences in patient demographics, anesthesia and surgery duration, and study treatment failure. The Glasgow CMPS-SF scores were significantly higher for IM compared with GV [2 (0 to 8) versus 1 (0 to 6), respectively; P = 0.044] at 4 hours. Sedation scores were significantly higher for IM compared with GV at 2 [2 (1 to 3) and 1 (1 to 3), respectively; P = 0.0004] and 4 [1 (1 to 3) and 1 (1 to 2), respectively; P = 0.03] hours. Pharmacopuncture with low-dose hydromorphone provided adequate postoperative analgesia in dogs undergoing ovariohysterectomy with reduced sedative effects. Pharmacopuncture is a good alternative in dogs when reduced dosing of opioids is recommended.

Comparison of clinical and inflammatory parameters in dogs with pyometra before and after ovariohysterectomy

This study aimed to identify potential biomarkers of canine pyometra and their correlations with clinical parameters. First, 90 dogs with pyometra and 26 healthy female dogs were compared. Then, paired samples (before and after ovariohysterectomy) from 22 dogs with pyometra and 9 healthy controls from the initial cohort were compared. Concentrations of acute inflammatory proteins, C-reactive protein (CRP) and serum amyloid A (SAA), and cell-free DNA (cfDNA), were significantly higher in dogs with pyometra than in clinically healthy dogs. Cell-free DNA was the most sensitive biomarker for systemic inflammation, based on the receiver operating characteristic curve analysis (area under the curve = 0.959). In addition, cfDNA and CRP were significantly associated with inflammation and organ injury-related clinical parameters. Following the surgical removal of the inflamed uterus, interleukin-6 (IL-6), high-mobility group box 1 (HMGB1), and procalcitonin (PCT) significantly decreased, whereas changes in CRP, SAA, and cfDNA were not significant. These findings indicate that cfDNA, CRP, and SAA are potential clinical biomarkers of systemic inflammation in dogs with pyometra and PCT, IL-6, and HMGB1 are potential biomarkers of clinical recovery.

Use of propofol to induce food consumption by anorectic dogs following ovariohysterectomy

OBJECTIVE

To determine whether IV propofol administration at a dose of 2 mg/kg (0.9 mg/lb) could induce food consumption by anorectic female dogs following elective ovariohysterectomy.

ANIMALS

51 healthy female dogs that failed to eat voluntarily when food was offered 6 hours after ovariohysterectomy.

PROCEDURES

In a randomized, blinded, controlled clinical trial, dogs received propofol (2 mg/kg; n = 31) or an equivalent volume of saline (0.9% NaCl) solution (20) IV 6 hours after ovariohysterectomy. Afterward, food was offered to the dogs and food consumption was reassessed. Pain, sedation, and stress were scored before and immediately after treatment.

RESULTS

27 of the 31 (87%) dogs in the propofol group consumed food immediately after administration of the assigned treatment, whereas only 1 of 20 (5%) dogs in the placebo group did. No difference in pain, sedation, or stress scores was identified between the 2 groups. Sedation scores for dogs in the propofol group increased immediately after propofol administration.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggested that food consumption following elective surgical procedures can be effectively induced in anorectic female dogs by IV administration of propofol at a dose of 2 mg/kg.

Factors influencing complications following mastectomy procedures in dogs with mammary gland tumors: 140 cases (2009-2015)

OBJECTIVE

To evaluate complication rates for various types of mastectomy procedures, identify factors associated with an increased risk of complications, and determine the consequences of such complications.

ANIMALS

140 female dogs that underwent 154 separate mastectomy procedures to treat mammary gland tumors.

PROCEDURES

Medical records of dogs in the Penn Vet Shelter Canine Mammary Tumor Program from July 2009 to March 2015 were reviewed. Data regarding signalment, tumor characteristics (ie, number and size, benign or malignant, and bilateral or unilateral), mastectomy type, anesthesia time, concurrent ovariohysterectomy or ovariectomy, surgeons' qualifications, antimicrobial administration after surgery, postoperative placement of surgical drains, and complications (seroma, abscess, dehiscence, or infection) were collected. Complications that required hospitalization were recorded. Fisher exact tests were used to evaluate associations between variables of interest and complications. Multivariable analysis was used to identify factors independently associated with an increased risk of complications.

RESULTS

Complication rate following all mastectomy procedures was 16.9% (26/154); of these, 9 (34.6%) required hospitalization. High body weight, undergoing bilateral mastectomy, and postoperative antimicrobial administration were associated with significantly increased odds of complications. The odds of complications associated with postoperative antimicrobial administration, however, varied according to mastectomy type; dogs undergoing chain mastectomy that did not receive antimicrobials postoperatively had the highest odds of developing complications. Dogs undergoing concurrent ovariohysterectomy or ovariectomy had significantly decreased odds of complications.

CONCLUSIONS AND CLINICAL RELEVANCE

Previously spayed dogs with a large body size that underwent the most extensive mastectomy procedures had increased odds of having postoperative complications.

Assessment of a vessel and tissue-sealing device for ovariectomy in chickens to evaluate the potential application of the procedure to other avian species

OBJECTIVE

To assess the feasibility of a novel technique involving a vessel and tissue-sealing device (VTSD) for ovariectomy in chickens to evaluate the potential application of the procedure to other avian species.

ANIMALS

20 domestic laying hens (Gallus domesticus), of which 10 were immature (< 4 months old) and 10 were adults (> 18 months old).

PROCEDURES

Ovariectomy was performed with a VTSD through a left lateral celiotomy. Birds were allowed to recover for 14 days after the procedure and then were euthanized for necropsy. A board-certified veterinary pathologist performed complete necropsies, with particular attention to identifying any remaining ovarian tissue.

RESULTS

All birds survived the procedure. For the mature and juvenile birds, the mean ± SD durations of anesthesia (interval from intubation to extubation) were 67.2 ± 7.6 minutes and 50.5 ± 5.1 minutes, respectively, and mean durations of surgery were 45.3 ± 8.5 minutes and 31.6 ± 5.1 minutes, respectively. Three birds had severe hemorrhage during ovariectomy. At necropsy, ovarian tissue was present grossly in 2 mature birds and histologically in 6 additional birds (2 mature and 4 juvenile birds), indicating incomplete excision in 8 (40%) birds.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that the evaluated VTSD can be used to successfully perform ovariectomies in both juvenile and mature chickens, although the procedure was associated with major hemorrhage and incomplete excision of ovarian tissue in some cases. Use of this VTSD for ovariectomy in birds of other species, particularly birds with reproductive tract disease, should be investigated.

Comparison of intra- and postoperative variables between laparoscopic and open ovariectomy in rabbits (Oryctolagus cuniculus)

OBJECTIVE

To compare intraoperative and short-term postoperative variables pertaining to laparoscopic ovariectomy (LapOVE) and open ovariectomy (OVE) in rabbits (Oryctolagus cuniculus).

ANIMALS

Twelve 4- to 5-month-old female New Zealand White rabbits.

PROCEDURES

Rabbits were randomly assigned to undergo LapOVE (n = 6) or OVE (6), with a vessel-sealing device used to seal and transect the ovarian pedicles. Laparoscopic ovariectomy was performed with a 3-port approach. Variables were measured during surgery (surgery and anesthesia times and incision lengths) and for up to 7 days after surgery (food consumption, feces production, body weight, vital parameters, blood glucose and cortisol concentrations, abdominal palpation findings, facial grimace scale scores, and ethograms).

RESULTS

Mean surgery (43.2 vs 21.7 minutes) and anesthesia (76.2 vs 48.8 minutes) times were longer and mean incision length was shorter (24.0 vs 41.5 mm) for LapOVE versus OVE. No significant differences in postoperative variables were identified between groups. During LapOVE, small intestinal perforation occurred in 1 rabbit, which was then euthanized. Postoperative complications for the remaining rabbits included superficial incisional dehiscence (LapOVE, 1/5; OVE, 2/6), subcutaneous emphysema (LapOVE, 1/5; OVE, 0/6), and seroma formation (LapOVE, 1/5; OVE, 0/6).

CONCLUSIONS AND CLINICAL RELEVANCE

Surgery time for LapOVE was twice that of OVE, and LapOVE resulted in unique complications in rabbits. No evidence of a reduction in pain or faster return to baseline physiologic status was found for LapOVE. Further evaluation of LapOVE in rabbits is warranted, with modification to techniques used in this study or a larger sample size.

The effects of eggshell calcium (Biomin H® ) and its combinations with alfacalcidol (1α-hydroxyvitamin D3) and menaquinone-7 (vitamin K2) on ovariectomy-induced bone loss in a rat model of osteoporosis

The purpose of this study was to investigate the impact of eggshell calcium (Biomin H® dietary supplement) and its combinations with alfacalcidol (1α-hydroxyvitamin D3 ) and menaquinone-7 (vitamin K2 ) on ovariectomy-induced bone loss in rats. Adult female rats (n = 48) were divided into 6 groups of 8 individuals each: sham-operated rats (SHAM); ovariectomized (OVX) rats untreated; OVX rats treated with Biomin H® (BIO); OVX rats simultaneously receiving Biomin H® , vitamin D3 (BIO + D3 ); OVX rats simultaneously treated with Biomin H® , vitamin K2 (BIO + K2 ) and OVX rats treated with Biomin H® , vitamin D3 , vitamin K2 (BIO + D3  + K2 ) during 8 weeks. Biochemical parameters, bone mineral density (BMD), bone mineral content (BMC) and femoral bone microstructure were determined. Plasma calcium and phosphate were increased in BIO + D3 and BIO + D3  + K2 groups as compared to OVX. Alkaline phosphatase was elevated in OVX, BIO versus SHAM, BIO + D3  + K2 groups. When compared to OVX group, decreased urine deoxypyridinoline was observed in all treated groups and femoral BMD, BMC were higher in BIO, BIO + D3 , BIO + D3  + K2 groups. The BIO + K2 rats had similar densitometrical values than OVX individuals. Microcomputed tomography revealed increased trabecular relative bone volume (due to an increase in trabecular number) in BIO + D3 , BIO + D3  + K2 as compared to OVX. The higher relative bone volume in BIO + D3 , BIO + D3  + K2 groups was also accompanied by an increase in bone surface. In the cortical bone, an enhanced periosteal bone apposition was identified in BIO, BIO + D3 , BIO + K2 , BIO + D3  + K2 groups. The rats from BIO + D3  + K2 group had a higher area of primary osteon's vascular canals. In BIO + D3 , BIO + K2 , BIO + D3  + K2 groups, an increased area of secondary osteons was determined in comparison with OVX. Our results indicate the beneficial effect of triple application of Biomin H® , vitamin D3 , vitamin K2 , as well as simultaneous administration of Biomin H® , vitamin D3 on the inhibition of ovariectomy-induced bone loss in a rat model of osteoporosis.

Cyclooxygenases 1 and 2 inhibition and analgesic efficacy of dipyrone at different doses or meloxicam in cats after ovariohysterectomy

OBJECTIVE

To evaluate the cyclooxygenases (COX) inhibition, adverse effects and analgesic efficacy of dipyrone or meloxicam in cats undergoing elective ovariohysterectomy.

STUDY DESIGN

Prospective, blinded, randomized, clinical study.

ANIMALS

A total of 30 healthy young cats.

METHODS

The cats were randomly assigned to three postoperative groups: D25 (dipyrone 25 mg kg^-1 every 24 hours), D12.5 (dipyrone 12.5 mg kg^-1 every 12 hours) and M (meloxicam 0.1 mg kg^-1 every 24 hours). In the first 24 hours, the drugs were administered intravenously (IV), and then orally for 6 (dipyrone) or 3 days (meloxicam). Prostanoids thromboxane B₂ and prostaglandin E₂ concentrations served as indicators of COX activity and, with physiological variables and pain and sedation scores, were measured for 24 hours after first analgesic administration. Rescue analgesia (tramadol, 2 mg kg^-1 IV) was provided if Glasgow feline composite measure pain scale (CMPS-Feline) ≥5. Laboratory tests included symmetric dimethylarginine and adverse effects were evaluated regularly up to 7 and 10 days after surgery, respectively. Parametric and nonparametric data were analyzed with two-way anova and Kruskal-Wallis tests, respectively (p < 0.05).

RESULTS

In the first half hour after analgesic administration, COX-1 activity was close to zero and remained significantly lower than before drug administration for 24 hours in all groups. The inhibition of COX-2 activity was significant for 30 minutes in all groups and up to 4 hours in group M. No alterations in laboratory tests or significant adverse effects were observed. Pain scores and need for rescue analgesia did not differ statistically among groups.

CONCLUSIONS

Dipyrone at both doses and meloxicam provided a nonselective inhibition of COX-1 and -2 activities and effective analgesia without causing significant adverse effects or laboratory tests alterations.

CLINICAL RELEVANCE

Dipyrone at both doses provides equally effective analgesia without causing adverse effects in cats undergoing ovariohysterectomy.

Comparison of the use of a vessel-sealing device versus ligatures for occlusion of uterine tissues during ovariohysterectomy or ovariectomy in rabbits (Oryctolagus cuniculus)

OBJECTIVE

To compare the bursting strength of the uterine horns (UHs) and cervical-vestibule junction (CVJs) of rabbits following sealing with a vessel-sealing device (VSD) or encircling ligatures.

SAMPLE

UHs and CVJs collected from 30 rabbit (Oryctolagus cuniculus) cadavers.

PROCEDURES

UHs and CVJs were randomly assigned to sealing with encircling Miller knot ligatures (LIG; n = 10 CVJs and 20 UHs) or a VSD (12 CVJs and 24 UHs). Lumens were infused with saline (0.9% NaCl) solution under pressure until seals burst or to a maximum pressure of 300 mm Hg.

RESULTS

For CVJs, median (range) bursting pressure of the LIG and VSD groups was > 300 mm Hg (224 to > 300 mm Hg) and 35 mm Hg (0 to 60 mm Hg), respectively. Five of 12 CVJs in the VSD group failed at pressures < 33 mm Hg. For UHs, median (range) bursting pressure of the LIG and VSD groups was 255 mm Hg (120 to > 300 mm Hg) and 154 mm Hg (range, 44 to 202 mm Hg), respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

The evaluated VSD was effective in sealing UHs at bursting pressures well in excess of expected physiologic pressures, indicating that the VSD may be useful for ovariectomy procedures in rabbits. However, CVJ seals created with the VSD were ineffective and could potentially burst at low pressures, which could predispose to urine entering the abdomen. Given these results, we do not recommend sealing of the CVJ with a VSD for ovariohysterectomy in rabbits.

Perioperative analgesia associated with oral administration of a novel methadone-fluconazole-naltrexone formulation in dogs undergoing routine ovariohysterectomy

OBJECTIVE

To determine perioperative analgesia associated with oral administration of a novel methadone-fluconazole-naltrexone formulation in dogs undergoing routine ovariohysterectomy.

ANIMALS

43 healthy female dogs.

PROCEDURES

Dogs were randomly assigned to receive the methadone-fluconazole-naltrexone formulation at 1 of 2 dosages (0.5 mg/kg, 2.5 mg/kg, and 0.125 mg/kg, respectively, or 1.0 mg/kg, 5.0 mg/kg, and 0.25 mg/kg, respectively, PO, q 12 h, starting the evening before surgery; n = 15 each) or methadone alone (0.5 mg/kg, SC, q 4 h starting the morning of surgery; 13). Dogs were sedated with acepromazine, and anesthesia was induced with propofol and maintained with isoflurane. A standard ovariohysterectomy was performed by experienced surgeons. Sedation and pain severity (determined with the Glasgow Composite Pain Scale-short form [GCPS-SF]) were scored for 48 hours after surgery. Rescue analgesia was to be provided if the GCPS-SF score was > 6. Dogs also received carprofen starting the day after surgery.

RESULTS

None of the dogs required rescue analgesia. The highest recorded GCPS-SF score was 4. A significant difference in GCPS-SF score among groups was identified at 6:30 am the day after surgery, but not at any other time. The most common adverse effect was perioperative vomiting, which occurred in 11 of the 43 dogs.

CONCLUSIONS AND CLINICAL RELEVANCE

Oral administration of a methadone-fluconazole-naltrexone formulation at either of 2 dosages every 12 hours (3 total doses) was as effective as SC administration of methadone alone every 4 hours (4 total doses) in dogs undergoing routine ovariohysterectomy. Incorporation of naltrexone in the novel formulation may provide a deterrent to human opioid abuse or misuse.

Immuno-castration of female and male pigs with anti-gonadotrophin releasing hormone vaccine: Morphometric, histopathological and functional studies of the reproductive system

Immuno-castration is increasingly recommended in pigs due to welfare reasons; however, there are few studies in females compared to males. This aim of this study was to investigate the effects of immuno-castration in female and male pigs. The weight, the morphometric and microscopic characteristics of the reproductive organs, and the hormone concentrations were studied in 12 immunocastrated females (IF) and 12 immunocastrated males (IM) and compared with control animals (C). At slaughter, IF tended to have greater body weights than CF (P =  0.051), whereas in IM and CM pigs there were not body weight differences (P =  0.140). The weight of the reproductive tract and size of all individual organs were less in IF compared with CF. Results from histological assessments indicated IF had more atretic follicles and a thinner endometrial mucosa than control females. Hormone concentrations were not different between CF and IF (P >  0.050). As a result of immuno-castration, there was impaired spermatogenesis in most males. Results from microscopic evaluations indicated there was a marked decrease of spermatogonial cells and size of Leydig cells in the testicles. Accessory gland structures were affected in CM and IM with there being differences in gross and microscopic characteristics. Testosterone concentrations, unlike estradiol, were different in IM compared to CM (P <  0.001). These results provide evidence that immuno-castration with the anti-gonadotrophin releasing hormone vaccine is effective in female and male pigs and induces morphological and endocrine changes incompatible with fertility.

Evaluation of nalbuphine, butorphanol and morphine in dogs during ovariohysterectomy and on early postoperative pain

OBJECTIVE

To evaluate the effects of nalbuphine, butorphanol and morphine combined with acepromazine on intraoperative and early postoperative pain management in dogs anesthetized for ovariohysterectomy.

STUDY DESIGN

Prospective, randomized blinded clinical study.

ANIMALS

A total of 48 healthy female dogs of different breeds, aged 1-6 years, weighing (mean ± standard deviation) 14.5 ± 4.8 kg.

METHODS

Dogs were randomly assigned into four groups to be intravenously administered nalbuphine (0.5 mg kg^-1; group N0.5), nalbuphine (1.0 mg kg^-1; group N1.0), butorphanol (0.4 mg kg^-1; group B0.4) or morphine (0.2 mg kg^-1; group M0.2) combined with acepromazine (0.02 mg kg^-1) prior to propofol and isoflurane for anesthesia. Heart rate (HR), respiratory rate, systolic arterial pressure and rectal temperature (RT) were recorded at time points during anesthesia. A dynamic interactive visual analog scale applied in three phases (DIVAS I, II and III) and the modified Glasgow composite measure pain scale were used to assess pain before premedication and 1, 2, 3, 4, 5 and 6 hours after extubation. Administration of rescue analgesia was recorded.

RESULTS

At the left ovarian pedicle ligation, HR was higher in N1.0 than in B0.4 (p = 0.020). RT decreased significantly by the end of surgery in N0.5 (p = 0.043) and B0.4 (p = 0.010). Rescue analgesia was administered postoperatively over 6 hours to eight, seven, nine and 10 dogs in N0.5, N1.0, B0.4 and M0.2, respectively (p = 0.57). DIVAS II was higher in B0.4 than in N1.0 at 2 and 3 hours (p = 0.038 and p = 0.002, respectively) and N0.5 at 3 hours (p = 0.003).

CONCLUSIONS AND CLINICAL RELEVANCE

At the doses used, all premedication protocols provided insufficient intraoperative analgesia, with minimal clinical differences between groups. No premedication provided satisfactory analgesia in the first 6 hours postoperatively.

Circuit-level analysis identifies target genes of sex steroids in ewe seasonal breeding

Thyroid hormone (TH) and estradiol (E2) direct seasonal switches in ovine reproductive physiology. In sheep, as in other mammals and birds, control of thyrotropin (TSH) production by the pars tuberalis (PT) links photoperiod responsiveness to seasonal breeding. PT-derived TSH governs opposite seasonal patterns of the TH deiodinases Dio2/Dio3 expression in tanycytes of the neighboring medio-basal hypothalamus (MBH), which explain the key role of TH. We recently used RNA-Seq to identify seasonal markers in the MBH and define the impact of TH. This impact was found to be quite limited, in terms of number of target genes, and very restricted with regards to neuroanatomical location, as TH specifically impacts genes expressed in tanycytes and hypothalamus, not in the PT. Here we address the impact of E2 on these seasonal markers, which are specifically expressed in either PT, tanycytes or hypothalamus. We also investigate if progesterone (P4) may be involved in timing the seasonal transition to anestrus. Our analysis provides circuit-level insights into the impact of sex steroids on the ewe seasonal breeding cycle. First, seasonal gene expression in the PT is independent of the sex steroid status. The fact that seasonal gene expression in the PT is also TH-independent strengthens the view that the PT is a circannual timer. Second, select tanycytic markers display some level of responsiveness to E2 and P4, which indicates another potential level of feedback control by sex steroids. Third, Kiss1 neurons of the arcuate nucleus are responsive to both TH and E2, which places them at the crossroads of photoperiodic transduction pathway and sex steroid feedback. This provides strong support to the concept that these Kiss1 neurons are pivotal to the long-recognized "seasonal switch in the ability of E2 to exert negative feedback", which drives seasonal breeding.

Investigation of associations between preoperative acepromazine or dexmedetomidine administration and development of arterial hypotension or bradycardia in dogs undergoing ovariohysterectomy

OBJECTIVE To evaluate potential associations between preanesthetic administration of acepromazine or dexmedetomidine and development of arterial hypotension or bradycardia in isoflurane-anesthetized dogs undergoing ovariohysterectomy. ANIMALS 341 dogs. PROCEDURES Medical records were searched to identify dogs that underwent ovariohysterectomy between January 2009 and December 2010 and received hydromorphone with acepromazine or dexmedetomidine as preanesthetic agents. Demographic data, sedative and anesthetic drugs, duration of anesthesia, average vaporizer setting, positive pressure ventilation, occurrence of hypotension (mean arterial pressure < 60 mm Hg) or bradycardia (> 50% reduction in heart rate, compared with the preanesthetic value), time to first occurrence and duration of hypotension, and treatment with dopamine or anticholinergic agents were recorded. Data were compared between dogs that received acepromazine and dexmedetomidine. Logistic regression was used to investigate associations between the treatments of interest (and other putative risk factors) and development of hypotension or bradycardia. RESULTS For dogs that received acepromazine, the odds of developing hypotension were 2.61 times those for dogs that received dexmedetomidine. Hypotension occurred earlier and lasted longer in dogs that received acepromazine, and this group was treated with dopamine more frequently than the group that received dexmedetomidine. Lower body weight was associated with increased odds of hypotension. Odds of developing bradycardia were greater for dogs sedated with dexmedetomidine (vs acepromazine) and for dogs that underwent anesthetic induction with propofol or a ketamine-benzodiazepine combination (vs thiopental). CONCLUSIONS AND CLINICAL RELEVANCE Anesthetic complications differed between isoflurane-anesthetized dogs undergoing ovariohysterectomy after premedication with acepromazine or dexmedetomidine in this study; future prospective investigations are warranted to investigate these effects in other, less homogenous populations of dogs.

Changes in interferon-gamma and neopterin in female dogs undergoing ovariohysterectomy as elective spay or as treatment of pyometra

The objective of this study was to determine serum concentrations of interferon-gamma (INF-γ) and neopterin (Np) in dogs with pyometra admitted for surgical treatment and to compare these concentrations to healthy dogs admitted for elective spay. The effects of the surgical procedure were also evaluated by measuring these markers in both groups of dogs before and after ovariohysterectomy. Our study indicates that pre-surgery concentrations of INF-γ (57.4 ± 26.0 pg/mL) and Np (5.6 ± 0.8 nmol/L) in healthy dogs were significantly lower compared to dogs with pyometra (124.3 ± 87.6 pg/mL for INF-γ; 7.0 ± 1.5 nmol/L for Np) (P < 0.05 in both cases). Furthermore, Np was lower in dogs with pyometra 3 days after surgery compared to healthy controls (P < 0.001). During the post-operative period, INF-γ showed no statistically significant changes in any of the groups, while Np showed lower serum concentration on day 3 than on day 0 in the pyometra group (P < 0.001). No statistically significant correlation was detected between serum concentrations of INF-γ and Np. These results indicate that pyometra causes alterations in serum concentrations of INF-γ and Np in female dogs compared to physiological levels before surgery and during the postoperative period.

Surgical treatment of spontaneous endometriosis in rhesus macaques (Macaca mulatta): 11 cases (2007-2011)

OBJECTIVE To determine long-term outcome for rhesus macaques (Macaca mulatta) with endometriosis that underwent surgical treatment and identify factors potentially associated with long-term outcome. DESIGN Retrospective case series. ANIMALS 11 female rhesus macaques. PROCEDURES Medical records of female rhesus macaques in which endometriosis was diagnosed between 2007 and 2011 and that underwent abdominal exploratory surgery were reviewed. RESULTS In 5 macaques, the only clinical abnormality was a caudal abdominal mass identified during a routine physical examination, and in 6 macaques, overt clinical signs of endometriosis, including anorexia, dysmenorrhea, and lethargy during menses, were reported. Five macaques had histologically confirmed complete ovarian removal, and another 5 had incomplete ovarian removal (ovarian tissue was not examined histologically in 1 macaque). Nine animals survived at least 12 months after surgery, and 6 survived at least 60 months after surgery. Macaques that did not have overt clinical signs were significantly more likely to survive at least 60 months after surgery. However, extent of ovarian removal was not significantly associated with survival 12 or 60 months after surgery. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that, in select situations, surgery (ovariectomy or ovariohysterectomy) may be curative in macaques with endometriosis and may result in long-term survival. Further, findings suggested that monitoring until clinical signs appear before performing surgery is not warranted in adult female macaques suspected to have endometriosis that only have a caudal abdominal mass and no other overt clinical signs.

Evaluation of combined assessments of serum anti-Müllerian hormone and progesterone concentrations for the diagnosis of ovarian remnant syndrome in dogs

OBJECTIVE

To determine the usefulness of combined assessments of serum anti-Müllerian hormone (AMH) and progesterone (P4) concentrations for diagnosis of ovarian remnant syndrome (ORS) in dogs.

DESIGN

Prospective case series.

ANIMALS

602 bitches that had previously undergone ovariohysterectomy or ovariectomy without hysterectomy and that were being evaluated for ORS.

PROCEDURES

Serum AMH and P4 concentrations were measured in a single serum sample obtained from each of the 602 dogs; results were classified as positive, negative, or inconclusive. Following AMH testing, submitting veterinarians were offered reimbursement for shipping and histologic evaluation of any tissue removed during treatment of dogs for which serum samples had been assessed.

RESULTS

Tissue samples were provided from 53 of 55 dogs that underwent surgical abdominal exploration. Of 48 dogs with histologically confirmed ORS, 25 were positive for both AMH and P4 and 23 were positive for AMH or P4 or test results were inconclusive. No dogs with histologically confirmed ORS were negative for both AMH and P4. Tissue samples that included no ovarian tissue were obtained from 5 dogs that were positive for both AMH and P4. In 2 dogs that were negative for both AMH and P4, no ovarian remnant was identified and no tissue was removed at the time of exploratory surgery.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that combined determination of AMH and P4 concentrations in a single serum sample can be an effective diagnostic test for spayed dogs suspected to have ORS. Histologic analysis of excised tissues to assess the completeness of surgical treatment in dogs with ORS is warranted.

Anesthetic and analgesic effects of an opioid-free, injectable protocol in cats undergoing ovariohysterectomy: A prospective, blinded, randomized clinical trial

This study evaluated the effects of ketamine-dexmedetomidine-midazolam as part of an opioid-free, multimodal protocol in cats undergoing ovariohysterectomy. In a prospective, blinded, randomized clinical trial, cats received either 1 of 2 doses of ketamine [5 mg/kg body weight (BW), n = 10, K5 or 7 mg/kg BW, n = 13, K7] with midazolam (0.25 mg/kg BW) and dexmedetomidine (40 μg/kg BW) intramuscularly, intraperitoneal bupivacaine (2 mg/kg BW) and subcutaneous meloxicam (0.2 mg/kg BW) after surgery. Buprenorphine (0.02 mg/kg BW, intravenously) was administered if pain scores exceeded intervention scores with 2 pain scoring systems. Similar prevalence of rescue analgesia was observed (K5 = 6/10; K7 = 7/13) with significantly lower requirements in kittens (2/8) than adults (11/15). Tachypnea (K5 = 7/10 and K7 = 9/13) and desaturation (K5 = 3/10 and K7 = 4/13) were the 2 most common complications. Age influenced the prevalence of rescue analgesia. Most adult cats required opioids for postoperative pain relief.

Measuring behavioral and physiological responses to pain mitigation for ovariectomy in Bos taurus yearling beef heifers

Ovariectomy (spaying) using the trans-vaginal dropped ovary technique (DOT) is performed to prevent pregnancy in cull female beef cattle that are not retained for breeding stock in areas practicing extensive grazing management. There are no reports describing analgesia for this surgical procedure. The objective of this study was to measure behavioral and physiological responses to determine whether an analgesic protocol of BXK [butorphanol (0.01 mg/kg), xylazine (0.02 mg/kg), and ketamine (0.04 mg/kg)] injected intramuscularly (i.m.) before spaying could mitigate procedural and immediate postsurgical pain, and whether oral meloxicam (1 mg/kg) administered at the time of spaying could mitigate postsurgical inflammatory pain. Forty-four red Angus and Angus crossbred yearling heifers (322 ± 27.0 kg BW) were randomly allocated to 1 of 3 groups: PALP (control; palpated but not spayed; n = 14), SPAY (spayed with no analgesia; n = 15), and BXKM (spayed with analgesia; n = 15). Behavioral measurements included visual analog scale (VAS) score, flight speed (FS), stride length (SL), and gait score (GS), as well as activity (lying, standing) and feeding behavior. Physiological measurements included salivary cortisol (SC), haptoglobin (Hp), serum amyloid A (SAA), substance P (SP), complete blood count (CBC), and rectal temperature (RT). Saliva and blood samples were collected, and RT, FS, SL, and GS were measured on day -1, day 0 (time of palpation/spaying), and hours 1, 2, 4, and days 1, 2, 4, and 7 after palpation/spaying. The BXKM heifers had lower SC concentrations than SPAY heifers at 1 h (P = 0.01) and 2 h (P = 0.004). Heifers treated with BXKM had Hp concentrations lower than SPAY heifers at 2 d (P = 0.01), 4 d (P < 0.001), and 7 d (P = 0.008), and lower Hp concentrations than PALP heifers at 4 d (P < 0.001). Concentrations of SAA were greater (P = 0.04) in BXKM heifers than in PALP heifers at 1 h and lower in PALP heifers than in BXKM heifers (P = 0.02) and SPAY heifers (P = 0.05) at 1 d. Heifers in the BXKM group had higher RT than PALP and SPAY heifers at 1 h (P < 0.001) and 2 h (P = 0.004). Results suggest that DOT ovariectomy is acutely stressful and painful and administration of BXK before spaying and meloxicam at the time of spaying mitigated the procedural and postsurgical stress, pain, and inflammation.

Changes in CO-oximetry values and pulse oximetry in isoflurane-anesthetized dogs with and without nitrous oxide

Concentrations of 64% to 70% nitrous oxide (N₂O) provide intra-operative analgesia. Clinically, pulse oximeter estimation (SpO₂) of oxygen (O₂) hemoglobin saturation (SaO₂) was observed to decrease with N₂O. Absorption atelectasis from breathing O₂ was thought to decrease arterial partial pressure of O₂ (PaO₂) below 70 mmHg and reduce SaO₂ and SpO₂ when N₂O was used. Administering N₂O from the beginning of the anesthesia might prevent atelectasis development and low PaO₂. The study was done in 2 parts (P < 0.05). In Part 1, isoflurane-anesthetized dogs undergoing ovariohysterectomy (n = 15 each group) breathed N₂O from anesthesia start (N₂O_early) or 1 hour later (N₂O_late). SpO₂, CO-oximetry values, and PaO₂ were compared to dogs breathing O₂ throughout anesthesia (control). Timing of N₂O introduction did not affect PaO₂ (lowest = 94 mmHg), SaO₂, or SpO₂. With N₂O, the lowest SpO₂ value was 91% and corresponded to a PaO₂ of 151 mmHg. Carboxyhemoglobin increased (highest = 2.7%) and SaO₂ decreased with N₂O (lowest = 96.7%). In Part 2, to replicate findings, 10 isoflurane-anesthetized dogs breathed N₂O, then O₂. With N₂O, SaO₂ did not decrease, but carboxyhemoglobin increased and returned to baseline once N₂O was discontinued. The dog with the highest carboxyhemoglobin (2%) had an SaO₂ of 96.8% (PaO₂ = 93 mmHg). Carboxyhemoglobin and SaO₂ changes were not clinically significant. Pulse oximetry did not reliably estimate SaO₂ but N₂O was not always a factor.