Effects of age and reproductive status on postoperative pain after routine ovariohysterectomy in cats

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.

Randomised, prospective, blinded, clinical trial of opioid-free injectable anaesthesia with or without multimodal analgesia in kittens undergoing ovariohysterectomy

OBJECTIVES

This study compared an opioid-free injectable anaesthetic protocol with or without multimodal analgesia in kittens undergoing ovariohysterectomy.

METHODS

In this prospective, randomised, blinded, clinical trial, 29 healthy kittens (mean ± SD weight 1.55 ± 0.46 kg; aged 10 weeks to 6 months) were included. Anaesthesia was performed with an intramuscular injection of ketamine (4 mg/kg), dexmedetomidine (40 μg/kg) and midazolam (0.25 mg/kg). In the multimodal group (MMG), cats (n = 14) received meloxicam (0.1 mg/kg SC) and intraperitoneal bupivacaine 0.25% (2 mg/kg), whereas the same volume of saline was administered in the control group (CG; n = 15). Atipamezole (0.4 mg/kg IM) was given 15 mins after ovariohysterectomy. Postoperative pain was assessed using the UNESP-Botucatu multidimensional feline pain assessment scale - short form. Rescue analgesia (buprenorphine 0.02 mg/kg IM in MMG/CG and meloxicam 0.1 mg/kg SC in CG) was administered if pain scores were ⩾4/12. Soft food intake (after 2 and 60 mins) was evaluated at specific time points postoperatively. Statistical analyses were performed with linear models and post-hoc pairwise comparison with Benjamini-Hochberg corrections (P <0.05).

RESULTS

The prevalence of rescue analgesia was higher in the CG (n = 15/15) than the MMG (n = 1/14; P <0.001). Pain scores at 1 h, 2 h and 4 h postoperatively were higher in the CG (4.1 ± 2.8, 4.8 ± 3.0 and 5.3 ± 1.2, respectively) than in the MMG (1.6 ± 1.0, 1.1 ± 1.0 and 0.9 ± 0.8, respectively; P <0.001). Food intake (%) at 1 h postoperatively was higher in the MMG after 2 and 60 mins (10.4 ± 9 and 71.9 ± 29, respectively) than in the CG (1.4 ± 2 and 13.9 ± 7, respectively; P <0.001).

CONCLUSIONS AND RELEVANCE

This opioid-free protocol using multimodal analgesia produced adequate postoperative pain relief, while almost eliminating the need for rescue analgesia in kittens undergoing ovariohysterectomy. Pain decreased food intake.

Analgesic efficacy of an ultrasound-guided transversus abdominis plane block with bupivacaine in cats: a randomised, prospective, masked, placebo-controlled clinical trial

OBJECTIVES

This randomised, prospective, masked clinical trial evaluated the postoperative analgesic efficacy of an ultrasound-guided transversus abdominis plane block (TAPB) with bupivacaine in cats undergoing ovariohysterectomy.

METHODS

Thirty-two healthy adult female cats undergoing elective ovariohysterectomy were randomised to undergo TAPB with bupivacaine (treatment group [TG], n = 16) vs placebo (control group [CG], n = 16) in addition to preoperative analgesia with buprenorphine (0.02 mg/kg IM). All patients received a general anaesthetic and, before surgical incision, a bilateral two-point (subcostal and lateral-longitudinal) TAPB was performed using 1 ml/kg bupivacaine 0.25% (0.25 ml/kg/point) or saline. Each cat was assessed by a blinded investigator before premedication (0 h) and at 1, 2, 3, 4, 8, 10 and 24 h postoperatively using the UNESP-Botucatu Feline Pain Scale - short form. Buprenorphine (0.02 mg/kg IV) and meloxicam (0.2 mg/kg SC) were administered when pain scores were ⩾4/12. Ten hours postoperatively, meloxicam was administered to cats that did not receive rescue analgesia. Statistical analysis included Student's t-tests, Wilcoxon tests and χ2 tests, and a linear mixed model with Bonferroni corrections (P <0.05).

RESULTS

Of the 32 cats enrolled, three in the CG were excluded from the analysis. The prevalence of rescue analgesia was significantly higher in the CG (n = 13/13) than in the TG (n = 3/16; P <0.001). Only one cat in the CG required rescue analgesia twice. Pain scores were significantly higher in the CG compared with the TG at 2, 4 and 8 h postoperatively. Mean ± SD pain scores were significantly higher in the CG, but not in the TG, at 2 (2.1 ± 1.9), 3 (1.9 ± 1.6), 4 (3.0 ± 1.4) and 8 h postoperatively (4.7 ± 0.6) than at 0 h (0.1 ± 0.3).

CONCLUSIONS AND RELEVANCE

A bilateral ultrasound-guided two-point TAPB with bupivacaine in combination with systemic buprenorphine provided superior postoperative analgesia than buprenorphine alone in cats undergoing ovariohysterectomy.

A randomized, prospective, masked clinical trial comparing an opioid-free vs. opioid-sparing anesthetic technique in adult cats undergoing ovariohysterectomy

This study aimed to compare the analgesic effects of an injectable protocol using multimodal analgesia with or without opioids in cats undergoing ovariohysterectomy (OVH). Thirty-two healthy cats were enrolled in a prospective, blinded, randomized trial after the caregiver's written consent. Cats received a combination of ketamine (4 mg/kg), midazolam (0.25 mg/kg) and dexmedetomidine (40 μg/kg), and either buprenorphine (20 μg/kg) or saline (same volume as buprenorphine) intramuscularly [opioid-sparing (OSA) and opioid-free anesthesia (OFA) groups, respectively]. Intraperitoneal bupivacaine 0.25% (2 mg/kg) and meloxicam (0.2 mg/kg subcutaneously) were administered before OVH. Atipamezole (400 μg/kg intramuscularly) was administered at the end of surgery. Pain and sedation were evaluated using the Feline Grimace Scale (FGS) and a dynamic interactive visual analog scale, respectively. Intravenous buprenorphine was administered as rescue analgesia if FGS scores ≥ 0.39/1. Statistical analysis included repeated measures linear mixed models, Fisher's exact test and Bonferroni adjustments when appropriate (p < 0.05). Twenty-seven cats were included. The prevalence of rescue analgesia was lower in OSA (n = 0/13) than in OFA (n = 5/14) (p = 0.04). The FGS scores (least square means and 95% CI) were higher in OFA at 1 [2.0 (1.3-2.7)] and 2 h [2.2 (1.5-2.9)] than baseline [0.7 (0.0-1.4)], but not in OSA. Sedation scores were not significantly different between groups. Opioid-free injectable anesthesia was appropriate for some cats using a multimodal approach. However, a single dose of intramuscular buprenorphine eliminated the need for rescue analgesia and assured adequate pain management after OVH in cats.

Evaluation of Targeted Bupivacaine, Bupivacaine-lidocaine-epinephrine, Dexamethasone, and Meloxicam for Reducing Acute Postoperative Pain in Cats Undergoing Routine Ovariohysterectomy

This study compared bupivacaine (BUP), bupivacaine-lidocaine-epinephrine (BLE), dexamethasone (DEX), and meloxicam (MEL) targeted at specific, potentially painful sites for reducing acute postoperative pain in cats undergoing elective ovariohysterectomy. One hundred fifty-one cats were included in a prospective, randomized, double-blinded clinical trial. Anesthesia consisted of a standardized protocol including buprenorphine, ketamine, dexmedetomidine, and isoflurane. A ventral midline ovariohysterectomy was performed, and cats were administered targeted injections of 0.5% bupivacaine (2 mg/kg); a combined 0.25% bupivacaine (1 mg/kg), 1% lidocaine (2 mg/kg), and 1:100,000 epinephrine (0.005 mg/kg); dexamethasone (0.125 mg/kg); or meloxicam (0.2 mg/kg) intraoperatively at the ovarian suspensory ligaments, uterine body, and incisional subcutaneous tissues. A 0-10 Numeric Pain Rating Scale (NRS) was used to assess cats postoperatively, 1 hour and 3 hours after anesthesia recovery prior to a same day discharge. Pain scores among evaluators were in good agreement with an overall Intraclass Correlation Coefficient (ICC) of 0.7897 (95% Confidence Interval 0.795-0.8313).  In all groups, overall pain scores 1-hour post anesthesia recovery were significantly higher than scores 3 hours post anesthesia recovery (P < .0001). Averaged pain scores compared among treatment groups did not differ at 1 hour post recovery. At 3-hours post anesthesia recovery, MEL group cats had significantly lower pain scores than the BLE group (P = .018). Study results indicate that early postoperative pain scores were similar for cats receiving local infiltrations of BUP, BLE, DEX, and MEL as part of a multimodal pain therapy for routine ovariohysterectomies. MEL showed somewhat better results 3 hours post anesthesia recovery, gaining significance over the BLE group.

Pressure Algometry for the Detection of Mechanical Nociceptive Thresholds in Horses

Simple Summary

It is difficult to measure pain in horses. As animals are not able to verbalize what they feel, we are left with trying to interpret the different signs that they display when they are in pain. Many of these signs are vague (e.g., not eating their food), but some are more readily identified if the animal moves away or lifts their leg when pressure is applied to a sensitive area. Pressure algometry is a tool used to detect responses to applied mechanical stimuli within painful and nonpainful tissues. Pressure algometry has been used in many different studies, but there is no consensus on how to synthesize this information to better diagnose and treat pain in horses. The purpose of this study was to summarize the results of these studies. Based on that review, we conclude that there is good evidence that pressure algometry is a reliable and objective method to measure pain responses. This information will help to improve the diagnosis and treatment of pain in horses.

Abstract

The clinical assessment of pain is subjective; therefore, variations exist between practitioners in their ability to identify and localize pain. Due to differing interpretations of the signs or severity of pain equine practitioners may assign varying levels of clinical significance and treatment options. There is a critical need to develop better tools to qualify and quantify pain in horses. Palpation is the most common method to detect local tenderness or sensitivity. To quantify this applied pressure, pressure algometry has been used to gradually apply pressure over specified landmarks until an avoidance response is noted, which is defined as the mechanical nociceptive threshold (MNT). Numerous studies have used pressure algometry in different applications to measure MNTs in horses. There is an acute need to establish normative values within different body regions and to develop standardized methods of testing MNTs to better guide practitioners in the diagnosis and treatment of pain. The aim of this systematic review was to summarize the evidence for the use of pressure algometry in horses. There is good evidence that pressure algometry is a repeatable, semi-objective method that can be used in a wide array of clinical and research applications to assess MNTs in horses.

Contrasting practices and opinions of UK-based veterinary surgeons around neutering cats at four months old

BACKGROUND

Many cats in the UK are not neutered before reaching potential breeding age. The purpose of this investigation was to understand the prevalence of veterinarians' behaviours around neutering cats at four months of age and to identify any needs of the veterinary profession on this.

METHODS

A sample of 483 veterinarians that completed a cross-sectional online questionnaire were included in quantitative and qualitative analyses.

RESULTS

Almost 70 per cent of veterinarians indicated they were comfortable carrying out neutering on cats of four months of age, and approximately half of veterinarians indicated they would recommend neutering client-owned cats at four months of age if practice policy permitted. There was no association found between these practices and geographic risk factors. Instead, neutering at four months was associated with the gender of the veterinarian, their practice policy and whether they routinely neuter unowned cats. Veterinarians have contrasting beliefs on similar themes, depending on whether they neuter kittens at four months or not, including differing opinions on general anaesthetic, surgery risks, owner compliance and their perceptions of neutering practices within the wider profession.

CONCLUSION

Familiarity and experience with the procedure, alongside perceived norms, are central to beliefs. We also highlight informational and learning barriers.

French veterinarians' opinions and practices regarding early neutering of cats: a convenience sampling survey interpreted in an international context

BACKGROUND

Although data are still needed, early neutering of cats appears to be as safe as neutering at the traditional age of six months or older and beneficial to the individual and the population. The aim of this observational study was to obtain an overview of veterinarians' opinions and practices about feline early neutering (ie, until the age of four months).

METHODS

In this retrospective work, a web survey was distributed to French practitioners.

RESULTS

A total of 609 veterinarians returned the survey. Majority of the veterinarians (56 per cent) reported never performing early neutering, 42 per cent reported performing it inconsistently, and 2 per cent reported consistently performing it. When carried out, it was mainly on kittens from commercial breeding, following breeders' request, and performed at the age of three months. An overwhelming majority (93 per cent) of veterinarians performing early neutering reported no incidents. Veterinarians who did not practise early neutering neutered mostly (81 per cent) kittens from four to six months of age.

CONCLUSION

In conclusion, early neutering is still not a common practice among French veterinarians. Opinions differed as to its advantages and disadvantages, although reported incidents were scarce. Veterinarians who do not perform early neutering reported a lack of interest in this practice rather than reluctance.

A retrospective internet-based survey of French cat breeders about early-age neutering

OBJECTIVES

The aim of this study was to analyse cat breeders' application of and opinions concerning early-age (ie, <16 weeks old) neutering in cats in France.

METHODS

This study analysed a retrospective cohort. A web survey was designed for French cat breeders and was published in June 2017 on the Facebook page of Livre Officiel des Origines Félines, the official feline studbook for purebred cats born in France. The early-age cat neutering habits, opinions and expectations of breeders were collected.

RESULTS

A total of 999 breeders returned the questionnaire. Almost half of the breeders (49%) reported consistently requesting neutering of kittens before selling them, 32% claimed that they never requested it and the remaining 19% reported that they inconsistently requested it. When performed, 83% of breeders had kittens neutered at 12 weeks of age; for a large majority of these breeders (94%), the neutering was undertaken on their own initiative. Various reasons for neutering were provided, including the prevention of uncontrolled breeding, short- and long-term welfare benefits for neutered cats, and practical and economic reasons. Reported incidents related to early-age neutering were scarce. Nearly half of breeders who did not apply early-age neutering to their kittens cited a veterinarian's unwillingness to perform the surgery as a cause.

CONCLUSIONS AND RELEVANCE

A large majority of surveyed French cat breeders supported early-age neutering that would occur before kittens were sold, most of the time at the age of 3 months. These breeders reported high satisfaction with early-age neutered cats, with a low number of incidents and accidents reported.

Evaluation of targeted bupivacaine for reducing acute postoperative pain in cats undergoing routine ovariohysterectomy

OBJECTIVES

This study sought to determine if bupivacaine targeted at specific, potentially painful sites could enhance postoperative analgesia in routine feline ovariohysterectomies. A secondary objective was to assess the utility of multiple acute pain scales for cats in a high-volume surgery setting.

METHODS

Two hundred and twelve cats were included in a prospective, randomized, double-blinded, placebo-controlled clinical trial. Anesthesia included buprenorphine, ketamine, dexmedetomidine and isoflurane. A ventral midline ovariohysterectomy was performed and cats were administered bupivacaine (2 mg/kg), placebo control (0.9% saline) or sham control (observation only) intraoperatively at the ovarian suspensory ligaments and vessels, uterine body and incisional subcutaneous tissues. Two pain scales were used to assess cats postoperatively. Initially, a multidimensional composite pain scale (MCPS) and a 0-10 numeric pain rating scale (NRS) were used. Subsequently, the MCPS was replaced with a modified Colorado State University Feline Acute Pain Scale (mCSU). Pain scores for the test groups were compared using a one-way ANOVA and a Holm-Bonferroni post hoc analysis when a difference was found (P <0.05).

RESULTS

Pain for the bupivacaine group was lower than the control groups at 1 h post-recovery and discharge, attaining significance with higher body weights. The P values were 0.008 and 0.004 for 1 h post-recovery and discharge, respectively. Pain scores between evaluators for the MCPS and NRS correlated poorly with r values for 1 h post-recovery and discharge of -0.08 and 0.22, respectively. Additionally, the MCPS proved difficult to use and time consuming, especially for feral and fractious patients, and was replaced with the mCSU.

CONCLUSIONS AND RELEVANCE

Targeted bupivacaine reduced early postoperative pain scores following routine feline ovariohysterectomies. The technique used was simple, requiring just over a minute to perform at minimal additional cost. The MCPS was not ideal for use in a high-volume spay setting.

Effect of non-steroidal anti-inflammatory drugs on postoperative respiratory and heart rate in cats subjected to ovariohysterectomy

Objectives The use of physiological parameters such as respiratory rate and heart rate to assess pain has long been discussed. The aim of the study was to compare postoperative respiratory rate and heart rate in cats subjected to flank ovariohysterectomy treated with a preoperative non-steroidal anti-inflammatory drug (NSAID) or no NSAID, and determine whether these parameters are suitable for postoperative pain assessment in cats. We hypothesised that cats without an NSAID would experience more postoperative pain, which may increase heart rate and respiratory rate. Methods A total of 168 female privately owned cats were studied. All cats were premedicated with medetomidine (0.08 mg/kg) and butorphanol (0.4 mg/kg) subcutaneously and anaesthesia was induced with intramuscular ketamine (5 mg/kg). Cats were divided into subgroups; controls (no NSAID) or cats given an NSAID, carprofen (4 mg/kg) or meloxicam (0.3 mg/kg), at premedication or induction of anaesthesia. Cats were subjected to flank ovariohysterectomy by the same surgeon. Atipamezole was administered 2.5 h after induction of anaesthesia. Respiratory rate and heart rate were measured 3.5 h after the induction of anaesthesia. Data were analysed using one-way ANOVA with mixed procedure and Tukey's adjustment method for multiplicity. Results The postoperative respiratory rate and heart rate per minute for all cats were 34.0 ± 8.6 and 167.5 ± 27.4, respectively. Neither respiratory rate nor heart rate differed significantly between the control group and the NSAID groups or between different time points of administration of NSAIDs. Conclusion and relevance Assuming there was less postoperative pain in the group administered NSAIDs, the results of the study presented no support for use of respiratory rate and heart rate as parameters for postoperative pain assessment in individual cats. Study limitations included a lack of pain scoring and baseline data for respiratory rate and heart rate.

Injectable anaesthesia for adult cat and kitten castration: effects of medetomidine, dexmedetomidine and atipamezole on recovery

Objectives Rapid recovery from injectable anaesthesia benefits cat shelter neutering programmes. The effects of medetomidine, dexmedetomidine and atipamezole on recovery were evaluated in adult cats and kittens (⩽6 months old). Methods One hundred healthy male cats (age range 2-66 months, weight range 0.7-5.3 kg) admitted forneutering were randomly allocated to groups of 25. Anaesthesia was induced with 60 mg/m2 ketamine, 180 µg/m2 buprenorphine, 3 mg/m2 midazolam and either 600 µg/m2 medetomidine (groups M and MA) or 300 µg/m2 dexmedetomidine (groups D and DA) intramuscularly (IM). Groups MA and DA also received 1.5 mg/m2 atipamezole IM after 40 mins. Preparation time, surgical time, and times to sternal recumbency and standing were recorded. Data were analysed using the Kruskall-Wallis test, unpaired t-tests and ANOVA. Statistical significance was deemed to be P ⩽0.05. Results Groups did not differ significantly in age, body weight, preparation or surgical time. The time to sternal recumbency in group MA (64 ± 34 mins) was less than in group M (129 ± 32 mins), and in group DA it was less than in group D (54 ± 6 mins vs 110 ± 27 mins) ( P <0.001). There were no differences in duration of recovery to sternal recumbency between groups M and D or MA and DA. The time to standing in group MA (79 ± 51 mins) was less than in group M (150 ± 38 mins) ( P <0.001), and in group DA it was less than in group D (70 ± 22 mins vs 126 ± 27 mins) ( P <0.01). Time to standing in group D (126 ± 27 mins) was less than in group M (150 ± 38 mins) (P <0.05). Time to standing in groups DA and MA were not different. Kittens recovered faster than adults after atipamezole. Minimal adverse effects were seen. Conclusions and relevance Atipamezole reliably reduced recovery time after anaesthesia incorporating either dexmedetomidine or medetomidine; however, the choice of dexmedetomidine or medetomidine had little effect. Recovery was faster in kittens.

Effect of age and surgical approach on perioperative wound complication following ovariohysterectomy in shelter-housed cats in Australia

Objectives

The aim of the study was to investigate the effects of age and/or surgical approach on perioperative wound complication following ovariohysterectomy (OHE).

Methods

A retrospective search of perioperative monitoring records from a shelter desexing program was conducted to identify cats that underwent OHE between 1 June 2010 and 31 December 2012 inclusive. A wound complication was defined as gross observation of inflammation or wound dehiscence at the surgical site in the 5 day postoperative period. Cases were grouped according to age (≤12 weeks or >12 weeks) and surgical approach (flank or midline). Stratified analyses were conducted to evaluate the association between surgical approach and wound complications, after adjusting for age. Mantel–Haenszel adjusted risk ratio, Cochran–Mantel–Haenszel test statistic and their 95% confidence intervals were presented.

Results

A total of 312 cases met the study criteria. The overall wound complication risk was low (6.09%) and was not related to age. A midline approach was associated with a 4.59-times increased risk of wound complication, compared with a flank approach in cats up to 12 weeks of age (P = 0.015) but not in older cats.

Conclusions and relevance

These findings support the practice of prepubertal desexing for cats.