Efficacy of tolfenamic acid and meloxicam in the control of postoperative pain following ovariohysterectomy in the cat

2024 ISFM and AAFP consensus guidelines on the long-term use of NSAIDs in cats

PRACTICAL RELEVANCE

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used and are effective for the management of pain in cats. These Guidelines will support veterinarians in decision-making around prescribing NSAIDs in situations of chronic pain, to minimise adverse effects and optimise pain management. Information is provided on mechanism of action, indications for use, screening prior to prescription, use in the presence of comorbidities, monitoring of efficacy, and avoidance and management of adverse effects.

CLINICAL CHALLENGES

The cat's unique metabolism should be considered when prescribing any medications, including NSAIDs. Chronic pain may be challenging to detect in this species and comorbidities, particularly chronic kidney disease, are common in senior cats. Management of chronic pain may be complicated by prescription of other drugs with the potential for interactions with NSAIDs.

EVIDENCE BASE

These Guidelines have been created by a panel of experts brought together by the International Society of Feline Medicine (ISFM) and American Association of Feline Practitioners (AAFP). Information is based on the available literature, expert opinion and the panel members' experience.

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.

Cardiopulmonary and propofol-sparing effects of dexmedetomidine in total intravenous anesthesia in cats undergoing ovariohysterectomy

OBJECTIVES

This study aimed to assess the effect of dexmedetomidine on the propofol-based anesthesia of cats subjected to ovariohysterectomy.

METHODS

Twenty-eight cats were randomly allocated to four groups (seven cats in each) and premedicated with either 5 µg/kg dexmedetomidine (groups Dex 1, Dex 3 and Dex 5) or 0.05 ml saline (Prop group) intramuscularly. After the induction of anesthesia with propofol, total intravenous anesthesia was initiated with 300 µg/kg/min propofol plus 3 ml/kg/h NaCl 0.9% (Prop), or 200 µg/kg/min propofol plus dexmedetomidine at the rates of 1 µg/kg/h (Dex 1), 3 µg/kg/h (Dex 3) or 5 µg/kg/h (Dex 5). Cardiorespiratory variables were assessed 5 mins after induction and every 10 mins thereafter, until the end of anesthesia. The propofol infusion rate was adjusted every 10 mins (± 50 µg/kg/min) to maintain anesthetic depth. The times to extubation, sternal recumbency, ambulation and total recovery were recorded. Pain scoring was performed 1, 2, 4, 8, 12 and 24 h after the end of anesthesia.

RESULTS

Dexmedetomidine produced a propofol-sparing effect of 72.8%, 71.1% and 74.6% in the Dex 1, Dex 3 and Dex 5 groups, respectively. Cats in the Prop group maintained higher heart rate values than the other groups, and the mean arterial pressure remained higher in the Dex 3 and Dex 5 groups. Rescue intraoperative analgesia (fentanyl bolus) was most frequent in the Prop group. There was no significant difference in the time of extubation. Cats in the Dex 1 and Dex 3 groups had a faster anesthetic recovery, with shorter times to achieving sternal recumbency, regaining ambulation and reaching full recovery. Cats in the Dex 1 and Dex 5 groups presented the best recovery quality scores, with 4 (range 4-5) and 4 (range 3-5), respectively, while the Prop group scored 1 (range 1-3), the worst anesthetic recovery score among the groups.

CONCLUSIONS AND RELEVANCE

The use of dexmedetomidine as a total intravenous anesthesia adjuvant, especially at doses of 1 and 3 µg/kg/h, reduces propofol consumption and improves cardiorespiratory stability and intraoperative analgesia, while promoting a better and quicker recovery from anesthesia.

Antinociceptive Effect of a Sacro-Coccygeal Epidural of Morphine and Lidocaine in Cats Undergoing Ovariohysterectomy

BACKGROUND

A commonly described analgesic protocol for ovariohysterectomy (OHE) combines systemic opioids, sedatives, and non-steroidal anti-inflammatory drugs. However, systemic analgesia does not fully prevent perioperative visceral and somatic pain triggered by the surgical stimulus.

OBJECTIVES

To compare the analgesic effects and quality of recovery of systemic analgesia with those of a sacrococcygeal epidural injection of lidocaine and morphine in cats undergoing elective OHE. Methods: Twenty domestic female cats were premedicated with dexmedetomidine (0.01 mg kg-1 IM) and alfaxalone (1.5 mg kg-1 IM) and randomly assigned to one of two analgesic protocols: methadone (0.2 mg kg-1 IM) in the control group CTR (n = 10) and methadone (0.1 mg kg-1 IM) + epidural (lidocaine 2% (0.3 mL kg-1) + morphine 1% (0.1 mg kg-1) diluted with NaCl 0.9% to a total volume of 1.5 mL in the SCC-E group (n = 10). General anaesthesia was induced with alfaxalone (1 mg kg-1 IV) and maintained with sevoflurane in 100% oxygen. Non-invasive blood arterial pressure and cardiorespiratory variables were recorded. The quality of recovery was assessed using a simple descriptive scale. Before surgery and 1, 2, 3, 4, 6, and 8 h post-op pain was assessed using the UNESP-Botucatu multidimensional composite pain scale (MCPS) and mechanical nociception thresholds (MNT). The repeated measures analysis of variance (ANOVA) was used to compare groups over time. Comparison between groups was performed using independent samples t-test if the assumption of normality was verified, or the Mann-Whitney test. The chi-square test of independence and exact Fisher's test were used to compare groups according to recovery quality.

RESULTS

Heart rate and systolic arterial pressure increased significantly from baseline values in the CTR group and did not change in the SCC-E group. In the CTR group, MNT and UNESP-Botucatu-MCPS scores increased significantly from baseline for all assessment points and the first 3 h, respectively, whereas this did not occur in the SCC-E group.

CONCLUSIONS AND CLINICAL RELEVANCE

Based on our results, the SCC-E administration of lidocaine 2% with morphine 1% is a reasonable option to provide perioperative analgesia in cats submitted to OHE, compared to a systemic protocol alone.

Effect of dose on the intravenous pharmacokinetics of tolfenamic acid in goats

The objective of this study was to determine the pharmacokinetics of tolfenamic acid (TA) following intravenous (IV) administration at doses of 2 and 4 mg/kg in goats. In this study, six healthy goats were used. TA was administered intravenously to each goat at 2 and 4 mg/kg doses in a cross-over pharmacokinetic design with a 15-day washout period. Plasma concentrations of TA were analyzed using the high performance liquid chromatography with ultraviolet detector, and pharmacokinetic parameters were assigned by noncompartmental analysis. Following IV administration at dose of 2 mg/kg, area under the concentration-time curve (AUC_0-∞ ), elimination half-life (t_1/2ʎz ), total clearance (Cl_T ) and volume of distribution at steady state (V_dss ) were 6.64 ± 0.81 hr^* µg/ml, 1.57 ± 0.14 hr, 0.30 ± 0.04 L h^-1  kg^-1 and 0.40 ± 0.05 L/kg, respectively. After the administration of TA at a dose of 4 mg/kg showed prolonged t_1/2ʎz , increased dose-normalized AUC_0-∞ , and decreased Cl_T . In goats, TA at 4 mg/kg dose can be administered wider dose intervals compared to the 2 mg/kg dose. However, further studies are needed to determine the effect of different doses on the clinical efficacy of TA in goats.

Comparison of perioperative analgesia using the infiltration of the surgical site with ropivacaine alone and in combination with meloxicam in cats undergoing ovariohysterectomy

Background

Infiltration of the surgical site with local anesthetics combined with nonsteroidal anti-inflammatory drugs may play an important role in improving perioperative pain control. This prospective, randomized, blinded, controlled clinical trial aimed to evaluate intraoperative isoflurane requirements, postoperative analgesia, and adverse events of infiltration of the surgical site with ropivacaine alone and combined with meloxicam in cats undergoing ovariohysterectomy. Forty-five cats premedicated with acepromazine/meperidine and anesthetized with propofol/isoflurane were randomly distributed into three treatments (n = 15 per group): physiological saline (group S), ropivacaine alone (1 mg/kg, group R) or combined with meloxicam (0.2 mg/kg, group RM) infiltrated at the surgical site (incision line, ovarian pedicles and uterus). End-tidal isoflurane concentration (FE’ISO), recorded at specific time points during surgery, was adjusted to inhibit autonomic responses to surgical stimulation. Pain was assessed using an Interactive Visual Analog Scale (IVAS), UNESP-Botucatu Multidimensional Composite Pain Scale (MCPS), and mechanical nociceptive thresholds (MNT) up to 24 h post-extubation. Rescue analgesia was provided with intramuscular morphine (0.1 mg/kg) when MCPS was ≥6.

Results

Area under the curve (AUC) of FE’ISO was significantly lower (P < 0.0001) in the RM (17.8 ± 3.1) compared to S (23.1 ± 2.2) and R groups (22.8 ± 1.1). Hypertension (systolic arterial pressure > 160 mmHg) coinciding with surgical manipulation was observed only in cats treated with S and R (4/15 cats, P = 0.08). The number of cats receiving rescue analgesia (4 cats in the S group and 1 cat in the R and RM groups) did not differ among groups (P = 0.17). The AUC of IVAS, MCPS and MNT did not differ among groups (P = 0.56, 0.64, and 0.18, respectively). Significantly lower IVAS pain scores were recorded at 1 h in the RM compared to the R and S groups (P = 0.021–0.018). There were no significant adverse effects during the study period.

Conclusions

Local infiltration with RM decreased intraoperative isoflurane requirements and resulted in some evidence of improved analgesia during the early postoperative period. Neither R nor RM infiltration appeared to result in long term analgesia in cats undergoing ovariohysterectomy.

Comparison of intraperitoneal ropivacaine and ropivacaine-dexmedetomidine for postoperative analgesia in cats undergoing ovariohysterectomy

OBJECTIVE

To investigate the intraperitoneal (IP) administration of ropivacaine or ropivacaine-dexmedetomidine for postoperative analgesia in cats undergoing ovariohysterectomy.

STUDY DESIGN

Prospective, randomized, blinded, positively controlled clinical study.

ANIMALS

A total of 45 client-owned cats were enrolled.

METHODS

The cats were administered intramuscular (IM) meperidine (6 mg kg^-1) and acepromazine (0.05 mg kg^-1). Anesthesia was induced with propofol and maintained with isoflurane. Meloxicam (0.2 mg kg^-1) was administered subcutaneously in all cats after intubation. After the abdominal incision, the cats were administered one of three treatments (15 cats in each treatment): IP instillation of 0.9% saline solution (group Control), 0.25% ropivacaine (1 mg kg^-1, group ROP) or ropivacaine and dexmedetomidine (4 μg kg^-1, group ROP-DEX). During anesthesia, heart rate (HR), electrocardiography, noninvasive systolic arterial pressure (SAP) and respiratory variables were monitored. Sedation and pain were assessed preoperatively and at various time points up to 24 hours after extubation using sedation scoring, an interactive visual analog scale, the UNESP-Botucatu multidimensional composite pain scale (MCPS) and mechanical nociceptive thresholds (MNT; von Frey anesthesiometer). Rescue analgesia (morphine, 0.1 mg kg^-1) IM was administered if the MCPS ≥6. Data were analyzed using the chi-square test, Tukey test, Kruskal-Wallis test and Friedman test (p < 0.05).

RESULTS

HR was significantly lower in ROP-DEX compared with Control (p = 0.002). The pain scores, MNT, sedation scores and the postoperative rescue analgesia did not differ statistically among groups.

CONCLUSIONS AND CLINICAL RELEVANCE

As part of a multimodal pain therapy, IP ropivacaine-dexmedetomidine was associated with decreased HR intraoperatively; however, SAP remained within normal limits. Using the stated anesthetic protocol, neither IP ropivacaine nor ropivacaine-dexmedetomidine significantly improved analgesia compared with IP saline in cats undergoing ovariohysterectomy.

Comparison of the effects of buprenorphine and methadone in combination with medetomidine followed by intramuscular alfaxalone for anaesthesia of cats undergoing ovariohysterectomy

OBJECTIVES

The aim of this study was to compare the quality of anaesthesia and analgesia between methadone and buprenorphine in combination with medetomidine after induction with intramuscular (IM) alfaxalone in cats undergoing ovariohysterectomy.

METHODS

Fifty-one female cats (American Society of Anesthesiologists status I-II), with a median age of 12 months (range 2-60 months), weighing a mean ± SD of 2.5 ± 0.5 kg, were recruited to the study. Cats were randomly allocated to receive medetomidine (600 µg/m2) and buprenorphine (180 µg/m2) (group MB) or medetomidine (500 µg/m2) and methadone (5 mg/m2) (group MM) IM. Anaesthesia was induced 15 mins later using alfaxalone (3 mg/kg) IM. Anaesthesia was maintained with isoflurane in oxygen. All cats received meloxicam preoperatively. Quality of premedication and induction and intraoperative physiological parameters were recorded. Atipamezole (50% of medetomidine dose) was administered at the end of surgery. Cats were assessed postoperatively by the same blinded observer using a simple descriptive scale, numeric rating scale, dynamic interactive visual analogue scale (DIVAS) and UNESP-Botucatu multidimensional composite pain scales, at 10, 20 and 30 mins post-extubation. Parametric and non-parametric data were compared using Student's t-test or Mann-Whitney U-tests, respectively.

RESULTS

Forty-one cats completed the study. No significant differences were detected between groups before or during anaesthesia. No cats required rescue analgesia. DIVAS scores at 10 mins were significantly less in the MM group compared with the MB. No differences between groups at any other time points were detected using the four metrology instruments.

CONCLUSIONS AND RELEVANCE

Both protocols provided good anaesthesia conditions for ovariohysterectomy in the cat.

Synergistic effect of tolfenamic acid and glycyrrhizic acid on TPA-induced skin inflammation in mice

Tolfenamic acid (TA) and glycyrrhizic acid (GA) are well-known components with anti-inflammatory properties. However, their combined effects on inflammation have not been well studied. The present study aimed to investigate the in vivo anti-inflammatory effects of TA combined with GA using a 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced mouse ear edema model, as well as the underlying mechanisms thereof. The results indicated that TA combined with GA led to a stronger inhibition on TPA-induced mouse ear edema compared to the singular treatments. In addition, the combined treatment significantly alleviated subcutaneous tissue inflammation caused by TPA. Further mechanistic investigations demonstrated that TA combined with GA decreased the levels of TPA-induced interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). Furthermore, the combined treatment effectively inhibited nuclear factor-κB (NF-κB), extracellular signal-regulated kinase (ERK1/2), c-Jun N-terminal kinase (JNK), phosphor-ERK1/2 and phosphor-JNK, which was accompanied by blocking of the activation and the phosphorylation in mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K)/Akt signaling pathways. Collectively, our findings revealed that different anti-inflammatory components used in combination lead to enhanced inhibitory effects against inflammation.

Antiinflammatory Drugs

This article reviews the mechanisms of action, clinical use, and recent scientific evidence for the use of nonsteroidal antiinflammatory drugs, grapiprant, acetaminophen (paracetamol), metamizole (dipyrone), and corticosteroids in pain management. The discussion is presented with an emphasis on the treatment of acute pain.

Use of non-steroidal anti-inflammatory drugs in porcine health management

OBJECTIVE

Treatment of inflammation and pain management is an important topic in the welfare of pigs. It is very difficult for veterinary practitioners to choose the most appropriate product for a certain problem. This review aims to summarise and discuss the characteristics of different non-steroidal anti-inflammatory drugs (NSAIDs), as well as paracetamol and metamizole, available for pigs in the European Union.

METHODS

The databases Pubmed, Google Scholar, CliniPharm CliniTox and European Medicines Agency were searched. Relevant terms (eg,'meloxicam', 'fever', 'swine', 'pig', 'inflammation', 'castration', 'pain') were used to search for original articles, reviews and books. Only peer-reviewed articles were used. References from studies were also analysed in order to find additional relevant studies.

CONCLUSION

Studies which have investigated the efficacy of NSAIDs for different conditions, using different treatment regimens, are scarce. Most studies focused on the efficacy of NSAID-related pain alleviation in piglet castration, as well as the anti-inflammatory potential of NSAIDs in experimental inflammation models. Little research has been carried out on the use of metamizole, tolfenamic acid, paracetamol and sodium salicylate and their effect in pigs.

Analgesic efficacy of laser acupuncture and electroacupuncture in cats undergoing ovariohysterectomy

The aim of this study was to compare the effects of laser acupuncture and electroacupuncture on postoperative pain and analgesic requirements in cats. In a prospective, randomized and blinded clinical study, thirty cats undergoing ovariohysterectomy were sedated with intramuscular (IM) ketamine (5 mg/kg), midazolam (0.5 mg/kg), and tramadol (2 mg/ kg). Before the induction of anesthesia, the animals were randomly distributed into three groups of ten cats each: LA: bilateral Stomach 36 (ST-36) and Spleen 6 (SP-6) acupoints were stimulated with an infrared laser; EA: bilateral ST-36 and SP-6 acupoints were stimulated with an electrical stimulus; Control: no acupuncture was applied. Postoperative analgesia was evaluated in the first 24 hr post-extubation using the Interactive Visual Analogue Scale and UNESP-Botucatu Multidimensional Composite Pain Scale. Rescue analgesia was provided with IM tramadol (2 mg/kg), and the pain scores were reassessed 30 min after the rescue intervention. If the analgesia remained insufficient, meloxicam (0.2 mg/kg IM, single dose) was administered. Data were analyzed using t-tests, the Mann-Whitney U test, and Friedman test. P<0.05 was considered significant. The pain scores did not significantly differ between the treatment groups at any time point (P>0.05). The prevalence of rescue analgesia was significantly higher in the Control group than in the LA and EA groups (P=0.033). Preoperative laser and electroacupuncture reduced the need for rescue analgesia during the first 24 hr after ovariohysterectomy.

Evaluation and comparison of postoperative analgesic effects of dexketoprofen and methadone in dogs

OBJECTIVE

To evaluate and compare the analgesic efficacy and adverse effects of dexketoprofen and methadone using a noninferiority trial, during the first 24 postoperative hours in dogs undergoing orthopaedic surgery.

STUDY DESIGN

Randomized, blinded clinical study.

ANIMALS

A total of 38 healthy dogs undergoing orthopaedic surgery.

METHODS

Dogs were premedicated with dexmedetomidine [1 μg kg^-1 intravenously (IV)] followed by dexketoprofen (1 mg kg^-1 IV; group DK) or methadone (0.2 mg kg^-1 IV; group M). Anaesthesia was induced with propofol and maintained with isoflurane in 60% oxygen. Postoperatively, dexketoprofen was administered every 8 hours (group DK) and methadone every 4 hours (group M). Analgesia was assessed at baseline and at 1, 2, 4, 6, 18 and 24 hours after extubation using a dynamic and interactive visual analogue scale (DIVAS), the short form of the Glasgow Composite Measure Pain Scale (CMPS-SF), mechanical wound thresholds (MWTs) and plasma cortisol levels. If CMPS-SF score was ≥5, rescue analgesia was administered. Data were analysed using a general linear mixed model, Mann-Whitney U test and chi-squared test as appropriate; a p value <0.05 was considered significant.

RESULTS

The CMPS-SF and DIVAS scores were significantly higher in group M compared with group DK and remained higher for a longer period in group M, although the differences were not clinically significant. No significant differences were found in MWT assessment between groups. Plasma cortisol level significantly increased 2 hours after extubation, without significant differences between treatments. Rescue analgesia was administered to three animals (one in group DK; two in group M).

CONCLUSION AND CLINICAL RELEVANCE

We conclude that 1 mg kg^-1 IV dexketoprofen administered every 8 hours during the first 24 hours postoperatively is noninferior to methadone in controlling pain after orthopaedic surgery in dog, although frequent pain assessments are recommended to adjust the analgesia plan.

Comparison of post-operative analgesic efficacy of tolfenamic acid and robenacoxib in ovariohysterectomized cats

The objective of this study was to evaluate the efficacy of a non-selective COX inhibitor (tolfenamic acid) and a selective COX-2 inhibitor (robenacoxib) for post-operative pain control in cats. Thirty cats undergoing ovariohysterectomy were randomly divided into three groups: the control (placebo) group, the tolfenamic acid (4 mg/kg/day) group, and the robenacoxib (1 mg/kg/day) group. Non-steroidal anti-inflammatory drugs (NSAIDs) were administered orally 2 hr before anesthesia induction and 24 and 48 hr post-operation. Buccal mucosal bleeding times (BMBTs) were assessed prior to anesthesia induction. Colorado pain scores and composite pain scores were evaluated in a blinded fashion before induction and 2, 8, 24, 30 and 48 hr post-operation. The Colorado pain scores of cats receiving robenacoxib were significantly lower than those of cats in the control group at 30 (P=0.0126) and 48 (P=0.0439) hr post-operation. The composite pain scores of cats from the robenacoxib group were lower than those of cats in the control group at 30 (P=0.0299) and 48 (P=0.0103) hr post-operation. The Colorado pain scores of cats receiving tolfenamic acid were significantly lower than those of cats in the control group at 30 hr (P=0.0186) post-operation. The composite pain scores in cats in the tolfenamic acid group were lower than the scores of cats in the control group at 24 (P=0.0403) and 48 (P=0.0413) hr post-operation. BMBTs remained within normal limits in all groups. Both tolfenamic acid and robenacoxib are useful for post-operative pain control in cats.

Tolfenamic Acid

Tolfenamic acid (TA) is a nonsteroidal antiinflammatory drug and belongs to the group of fenamates. It is used as a potent pain reliever in the treatment of acute migraine attacks, and disorders like dysmenorrhea, rheumatoid, and osteoarthritis. TA has shown excellent in vitro antibacterial activity against certain ATCC strains of bacteria when complexed with bismuth(III). It has also been reported to block pathological processes associated with Alzheimer's disease. In the recent past, TA has also been used as a novel anticancer agent for the treatment of various cancers. In view of the clinical importance of TA, a comprehensive review of the physical and pharmaceutical properties and details of the various analytical methods used for the assay of the drug in pharmaceutical and biological systems has been made. The methods reviewed include identification tests and titrimetric, spectrophotometric, chromatographic, electrochemical, thermal, microscopic, enzymatic, and solid-state techniques. Along with the analytical profile, the stability and degradation of TA, its pharmacology and pharmacokinetics, dosage forms and dose, adverse effects and toxicity, and interactions have been discussed.

Clinical efficacy and pharmacokinetics of meloxicam in Mediterranean buffalo calves (Bubalus bubalis)

The aims of the investigation were to establish for the first time (i) clinical efficacy and (ii) pharmacokinetic profile of meloxicam intravenously (IV) administered in male Mediterranean buffalo calves after surgical orchiectomy. The study was performed on 10 healthy buffalo calves, between 4 and 5 months old and between 127 and 135 kg of body weight (b.w.). An IV injection of 0.5 mg/kg b.w. of meloxicam was administered in six calves (treated group, TG) immediately after surgery; the other four animals were used as untreated control group (CG). The clinical efficacy of meloxicam was evaluated pre- and post-surgery by monitoring respiratory rate (RR), heart rate (HR), rectal temperature (T°C), serum cortisol levels (SCL) and pain score (PS). Significant inter-groups differences were detected at sampling times (T): 4 hour (h) for RR (P<0.05), at T1-4-6-8 h for PS (P<0.05) and at T4-6-8 h for SCL (P < 0.0001). Regarding the mean intra-group values observed pre (T0) and post-surgery (from T15 min to T72 h), significant difference between the groups were found for RR (P<0.01), PS and SCL (P<0.05). The pharmacokinetic profile was best fitted by a two-compartmental model and characterized by a fast distribution half-life and slow elimination half-life (0.09 ± 0.06 h and 21.51 ± 6.4 h, respectively) and meloxicam mean concentrations at 96 h was of 0.18 ± 0.14 μg/mL. The volume of distribution and clearance values were quite low, but reasonably homogenous among individuals (V_dss 142.31 ± 55.08 mL/kg and Cl_B 4.38 ± 0.95 mL/kg/h, respectively). The IV administration of meloxicam in buffalo calves shows encouraging effects represented by significant and prolonged analgesic effects, significant reduction of SCL as well as similar pharmacokinetic profile to bovine calves.

Dexmedetomidine-methadone-ketamine versus dexmedetomidine-methadone-alfaxalone for cats undergoing ovariectomy

OBJECTIVE

To compare the duration, quality of anaesthesia and analgesia, and quality of recovery of dexmedetomidine and methadone combined with either ketamine or alfaxalone.

STUDY DESIGN

Randomized, prospective clinical trial.

ANIMALS

A group of 44 healthy client-owned cats presenting for ovariectomy.

METHODS

Cats were randomly assigned to one of the two treatment groups: DAM (n=22), which was administered intramuscularly (IM) dexmedetomidine (15 μg kg^-1), methadone (0.3 mg kg^-1) and alfaxalone (3 mg kg^-1), and DKM (n=22), which was administered IM dexmedetomidine (15 μg kg^-1), methadone (0.3 mg kg^-1) and ketamine (3 mg kg^-1). During anaesthesia, heart rate, respiratory rate and systolic arterial pressure were measured every 5 minutes. Cats that moved or had poor muscle relaxation were administered an additional 1 mg kg^-1 of either alfaxalone (DAM) or ketamine (DKM) intravenously (IV). In cases of increased autonomic responses to surgical stimulation, fentanyl (2 μg kg^-1) was administered IV. At the end of the surgery, atipamezole (75 μg kg^-1) was administered IM, and the times to both sternal recumbency and active interaction were recorded. Quality of recovery was evaluated with a simple descriptive scale. The UNESP-Botucatu multidimensional composite pain scale and a visual analogue scale were used to evaluate postoperative analgesia at the return of active interaction and 1, 2 and 3 hours later.

RESULTS

The additional anaesthesia and rescue fentanyl requirements were similar between groups. The quality of recovery was better in the DAM group than in the DKM group [simple descriptive scale scores: 0 (0-1) and 1 (0-3), respectively; p=0.002]. Postoperative pain scores decreased progressively over time in both groups, with no significant differences (p=0.08) between them.

CONCLUSIONS AND CLINICAL RELEVANCE

Both protocols provided comparable quality of anaesthesia and analgesia and were suitable for cats undergoing ovariectomy. In combination with methadone and dexmedetomidine, alfaxalone and ketamine showed comfortable and reliable recoveries.

Analgesic efficacy of intraperitoneal administration of bupivacaine in cats

Objectives The aim of this study was to evaluate the analgesic efficacy of intraperitoneal (IP) bupivacaine in cats undergoing ovariohysterectomy (OVH). Methods Forty-five cats were included in a randomized, prospective, blinded study after owners' written consent was obtained. The anesthetic protocol included acepromazine-buprenorphine-propofol-isoflurane. A ventral midline incision was made and cats (n = 15/group) were administered either IP saline 0.9% (negative and positive control groups; NG and PG, respectively) or IP bupivacaine (2 mg/kg; bupivacaine group; BG). Cats in the PG received meloxicam (0.2 mg/kg SC). An OVH was performed and postoperative pain was evaluated using a dynamic interactive visual analog scale (DIVAS), the UNESP-Botucatu multidimensional composite pain scale (MCPS) and mechanical nociceptive thresholds (MNT) for up to 8 h after the end of surgery. Postoperative sedation was evaluated using DIVAS. Rescue analgesia was provided with buprenorphine and/or meloxicam. Repeated measures linear models and a Cochran-Mantel-Haenszel test were used for statistical analysis ( P <0.05). Results There was a significant effect of treatment on the number of times rescue analgesia was administered ( P = 0.002) (PG, n = 2, 13%; NG, n = 12, 80%; BG, n = 4, 27%) with the number of rescues being higher in the NG group than in the PG ( P = 0.0004) and BG ( P = 0.02) groups. The DIVAS, MCPS and MNT were significantly different when compared with baseline values at different time points; however, data were not significantly different among groups. Conclusions and relevance Treatments PG and BG produced similar analgesia in terms of pain scores, number of times rescue analgesia was administered and MNT. Based on rescue analgesia, IP administration of bupivacaine provides analgesia in cats after OVH.

Systematic review of the behavioural assessment of pain in cats

OBJECTIVES

The objectives were to review systematically the range of assessment tools used in cats to detect the behavioural expression of pain and the evidence of their quality; and to examine behavioural metrics (considering both the sensory and affective domains) used to assess pain.

METHODS

A search of PubMed and ScienceDirect, alongside articles known to the authors, from 2000 onwards, for papers in English was performed. This was followed by a manual search of the references within the primary data sources. Only peer-reviewed publications that provided information on the assessment tool used to evaluate the behavioural expression of pain in cats, in conscious animals (not anaesthetised cats), were included.

RESULTS

No previous systematic reviews were identified. One hundred papers were included in the final assessment. Studies were primarily related to the assessment of pain in relation to surgical procedures, and no clear distinction was made concerning the onset of acute and chronic pain. Ten broad types of instrument to assess pain were identified, and generally the quality of evidence to support the use of the various instruments was poor. Only one specific instrument (UNESP-Botucatu scale) had published evidence of validity, reliability and sensitivity at the level of a randomised control trial, but with a positive rather than placebo control, and limited to its use in the ovariohysterectomy situation. The metrics used within the tools appeared to focus primarily on the sensory aspect of pain, with no study clearly discriminating between the sensory and affective components of pain.

CONCLUSIONS AND RELEVANCE

Further studies are required to provide a higher quality of evidence for methods used to assess pain in cats. Furthermore, a consistent definition for acute and chronic pain is needed. Tools need to be validated that can detect pain in a range of conditions and by different evaluators (veterinary surgeons and owners), which consider both the sensory and emotional aspects of pain.

Botulinum toxin type A as an adjunct in postoperative pain management in dogs undergoing radical mastectomy

The aim of this randomised placebo-controlled, observer-blinded study was to evaluate the analgesic effects of botulinum toxin type A (BoNT-A) as an adjunct for postoperative pain control in dogs. Sixteen dogs undergoing bilateral radical mastectomy for treatment of mammary tumours were enrolled. Twenty-four hours before surgery, the subjects were distributed into two groups of eight dogs each: 7 iu/kg BoNT-A (BoNT-A) or saline (Control) was administered subcutaneously in each mammary gland. Following sedation with intramuscular 0.03 mg/kg acepromazine and 0.3 mg/kg morphine, anaesthesia was induced intravenously with 4 mg/kg propofol and maintained with isoflurane/O2. Postoperative analgesia was evaluated for 72 hours after extubation using the Visual Analogue Scale (VAS) and modified Glasgow Composite Measure Pain Scale (modified-GCMPS). Rescue analgesia was provided with intramuscular morphine (0.5 mg/kg). Data were analysed using analysis of variance, Tukey's test, Mann-Whitney U test and Friedman test (P<0.05). The pain scores were significantly lower in the BoNT-A than in the Control from 8 hours to 60 hours and from 12 hours to 60 hours after extubation, based on the VAS and modified-GCMPS, respectively. Rescue analgesia was required by significantly more dogs in the Control (7/8) compared with the BoNT-A (2/8) (P=0.022). Pre-emptive BoNT-A appears to be effective as an adjuvant for postoperative pain management in dogs undergoing bilateral radical mastectomy.

Robenacoxib versus meloxicam for the control of peri-operative pain and inflammation associated with orthopaedic surgery in cats: a randomised clinical trial

Background

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used in veterinary medicine. Robenacoxib is a NSAID with high selectivity for the cyclo-oxygenase-2 enzyme. In this study, the efficacy and safety of robenacoxib were evaluated in a prospective, randomised, active- and placebo-controlled masked clinical trial in 147 cats undergoing orthopaedic surgery. Cats were randomised into two treatment groups: Group 1, robenacoxib (2 mg/kg) administered via subcutaneous (s.c.) injection before surgery, followed by robenacoxib tablets (1–2.4 mg/kg) administered post-operatively for approximately 9 days (n = 101) and Group 2, meloxicam (0.3 mg/kg) administered s.c. before surgery, followed by placebo tablets administered post-operatively for approximately 9 days (n = 46). Cats were assessed using numerical rating scales (NRSs) by clinicians before surgery and at 3, 8, 22 and 28 hours after surgery and at the final visit (VF on approximately Day 10), and daily by their owners from Day 1 to the VF.

Results

The primary end point was the global investigator score which was the sum of clinician NRSs for posture, behaviour and pain on palpation/manipulation. The efficacy of the single robenacoxib injection, assessed during 3 to 22 hours, was statistically non-inferior to meloxicam, with a relative efficacy of 1.029 (95% confidence interval, 0.847–1.231). No significant differences were detected during the follow-up treatment with robenacoxib tablets for approximately 9 days compared with placebo via clinician assessments at 28 hours and the VF, or in owner assessments on Days 1–VF. There were no significant differences in frequencies of reported adverse events, clinical observations and haematology or clinical chemistry variables between the groups.

Conclusions

Single s.c. injection of robenacoxib before surgery had non-inferior efficacy compared with meloxicam in controlling post-operative pain and inflammation in cats undergoing orthopaedic surgery. Follow-up treatment with oral robenacoxib tablets for approximately 9 days was well tolerated, but there were no differences in the efficacy scores after Day 1 compared with the group receiving meloxicam s.c. followed by placebo control.

Comparison of Surgical Variables and Pain in Cats Undergoing Ovariohysterectomy, Laparoscopic-Assisted Ovariohysterectomy, and Laparoscopic Ovariectomy

Laparoscopy is an established modality in veterinary medicine. To date, laparoscopy in feline surgery is rarely reported. The objectives of this study were to compare surgical time, complications, and postoperative pain in a group of cats undergoing laparoscopic ovariectomy (LOVE), laparoscopic-assisted ovariohysterectomy (LAOVH), and ovariohysterectomy via celiotomy (COVH). Eighteen healthy cats were randomly assigned to undergo LOVE, LAOVH, or COVH. Severity of pain was monitored 1, 2, 3, and 4 hr after surgery. Surgical time was significantly longer for LAOVH (mean ± standard deviation [SD], 51.6 ± 7.7 min) compared to COVH (mean ± SD, 21.0 ± 7.1 min) and LOVE (mean ± SD, 34.2 ± 11.2 min). There were no major intraoperative complications, although minor complications were more common in both laparoscopic groups. Cats sterilized via laparoscopy (LOVE and LAOVH) were statistically less painful than cats spayed via celiotomy (COVH) 4 hr following surgery. Results suggested that LOVE in cats is safe, can be performed in a comparable amount of time as COVH, and may result in less postoperative discomfort.

Evaluation of the clinical use of tepoxalin and meloxicam in cats

Medical records where tepoxalin (Zubrin) or meloxicam (Metacam) were prescribed in cats were reviewed and data extracted. Comparisons were performed for exploring changes between pre- and post-non-steroidal anti-inflammatory drug course laboratory tests. Seventy-nine medical records fit the inclusion criteria (n = 57 and n = 22, tepoxalin and meloxicam, respectively). The median dosages administered were 13 and 0.029 mg/kg(/)day (tepoxalin and meloxicam, respectively). Median prescription durations were 11 (2-919) and 93 (4-1814) days for tepoxalin and meloxicam, respectively. Suspected adverse events were reported for tepoxalin (9%, 5/57 cats) and meloxicam (18%, 4/22 cats) a median of 774 and 448 days, respectively, after the prescription started. For cats prescribed meloxicam, there were several statistically significant changes for serum biochemistry and hematology parameters, but median values were within normal limits. These valuable clinical data suggest that tepoxalin and meloxicam are well tolerated in the clinical setting at the doses prescribed in this study.

Lack of inhibitory effect of acetylsalicylic acid and meloxicam on whole blood platelet aggregation in cats

OBJECTIVE

To determine the effects of acetylsalicylic acid (ASA) and meloxicam on feline platelet aggregation and associated platelet thromboxane production and serotonin release.

DESIGN

Prospective interventional study.

SETTING

University research facility.

ANIMALS

Eight healthy male castrated domestic short hair cats from a research colony.

INTERVENTIONS

Oral medications were administered to 8 cats for 14 days in a randomized, placebo-controlled, crossover design. Treatment groups included: aspirin (ASA) (5 mg/kg q 48 h), meloxicam (0.05 mg/kg q 24 h), and placebo (0.5 mL of water q 24 h). Thromboxane assays (TXB(2) ) and whole blood (impedance) aggregometry (WBA) were performed on samples collected before drug administration, and on days 7, 15, and 17, using adenosine diphosphate (ADP; 10 μM) and collagen (5 μg/mL) as agonists for WBA. Serotonin release was assayed on postaggregation plasma. Oral mucosal bleeding time (OMBT) and complete blood cell counts were measured on days 0 and 15.

MEASUREMENTS AND MAIN RESULTS

Neither medication affected WBA at any time point. OMBT decreased in the ASA group relative to baseline. No differences were detected in WBA and OMBT baseline between any groups. No difference was detected in serotonin secretion at any time point. TXB(2) was significantly decreased in the ASA group at all times after initiation of treatment but no change was noted in the meloxicam or placebo groups.

CONCLUSIONS

At the doses studied, neither meloxicam nor ASA had an inhibitory effect on WBA or OMBT in cats. Thromboxane concentrations were significantly decreased with ASA treatment.

Clinical evaluation of meloxicam versus ketoprofen in cats suffering from painful acute locomotor disorders

The aim of this study was to evaluate the efficacy and palatability of meloxicam 0.5mg/ml oral suspension, compared to ketoprofen tablets in cats suffering from painful acute locomotor disorders. This single blinded, positively-controlled, randomised, multicentre trial involved 121 client owned cats. Cats received either meloxicam (0.5mg/ml oral suspension) at 0.1mg/kg on day 1 followed by 0.05mg/kg q 24h on days 2-5, or ketoprofen 5mg tablets at 1.0mg/kg q 24h for 5 days. The efficacy of the two treatments was assessed subjectively by clinicians on day 6 using a clinical sum score (CSS). Palatability and accuracy of dosing were also assessed. The baseline CSS was not significantly different between the groups, and after 5 days of treatment the CSS had decreased to a similar extent, reflecting a reduction in pain. There were no significant differences between the CSS of each group at day 6. Both treatments were well tolerated. Meloxicam was significantly more palatable than ketoprofen, and allowed for more accurate dosing. Meloxicam and ketoprofen are a safe and efficacious treatment for acute locomotor disorders in cats. Meloxicam (Metacam) may be associated with superior compliance in clinical practice due to the higher palatability, which results in better ease of administration.

ISFM and AAFP consensus guidelines: long-term use of NSAIDs in cats

NSAIDS AND CATS: Non-steroidal anti-inflammatory drugs (NSAIDs) are an important class of drug in feline medicine, having analgesic, anti-inflammatory and antipyretic activity. While most published data on their use in this species relate to short-term (often perioperative) therapy, there is increasing evidence of the value of these drugs in treating chronic pain in cats (for example, that associated with degenerative joint disease), and some NSAIDs have now become licensed for long-term use in cats in some geographies. Most of our knowledge of therapeutic mechanisms or adverse drug reactions associated with NSAIDs is extrapolated from work in other species, and there is a paucity of published data relating to cats.

GUIDELINES

These guidelines have been drawn together by an expert panel, which have reviewed the current literature on long-term NSAID use in cats and other species, and developed guidance on their use based on this information. The aim is to provide practical information for veterinarians to encourage appropriate NSAID therapy whenever cats will benefit from the use of these drugs.

The use of propofol and sevoflurane for surgical anaesthesia in New Zealand White rabbits

New Zealand White (NZW) rabbits ( n = 34) received intravenous propofol (16 ± 5 mg/kg) for induction of anaesthesia followed by maintenance with sevoflurane (4.0 ± 0.5%) in oxygen. All animals underwent ovariohysterectomy. Heart rate, respiratory rate, haemoglobin oxygen saturation, end-tidal carbon dioxide concentration, end-tidal sevoflurane concentration and oesophageal temperature were monitored every 5 min. Time from induction of anaesthesia to tracheal extubation and sternal recumbency were recorded as was the quality of recovery. Direct arterial blood pressure values (mmHg) were recorded every 5 min from 19 rabbits and 22 arterial blood gases analyses were performed (11 postintubation and 11 at the time of recovery). Propofol produced smooth induction of anaesthesia without production of apnoea. Intubation was successfully performed in all but one rabbit in an average of 4 ± 3 min from the beginning of propofol administration. No ventilatory support was required during the anaesthetic period. Respiratory rate averaged 51 ± 8 bpm and end-tidal CO2 (kPa) was 4.0 ± 0.5 mmHg during anaesthesia. Blood gas values were maintained within normal limits and average mean arterial blood pressure was 73.4 ± 7.9 mmHg. Time to regain the swallowing reflex following discontinuation of sevoflurane was 2 ± 1 min and time to sternal recumbency was 8 ± 0.3 min. No anaesthetic-related mortality occurred and all animals recovered uneventfully. Propofol–sevoflurane anaesthesia produced a good quality of surgical anaesthesia for ovariohysterectomy and stable cardiopulmonary conditions. Propofol–sevoflurane anaesthesia in young healthy NZW rabbits appears to be an effective and practically useful method of anaesthesia.

DJD-associated pain in cats: what can we do to promote patient comfort?

PRACTICAL RELEVANCE

Degenerative joint disease (DJD) has a high prevalence in domestic cats and can be associated with pain. This pain should be addressed wherever possible.

AUDIENCE

All practitioners are faced with cats that are mobility impaired due to DJD-associated pain.

PATIENT GROUP

Cats of all ages and breeds, and either sex, can experience DJD-associated discomfort.

CLINICAL CHALLENGES

Recognizing DJD and assessing DJD-associated pain in cats is a challenge. Owner observations of activity and behavior, careful observation and a logical and thorough orthopedic evaluation are key. Current understanding of the etiology of feline DJD and the mechanisms of DJD-associated pain is incomplete, making the rational choice of treatments a further challenge.

EVIDENCE BASE

Evidence is emerging on the prevalence of feline DJD, and on how to assess the associated pain and mobility impairment. There is a lack of information on the etiology of feline DJD and a relative lack of data on the efficacy of putative treatments.