Pain Management In Dogs Research Articles

Perioperative Pain Management in Dogs and Cats: Attitudes and Practices Among Thai Veterinarians

Perioperative Pain Management in Dogs and Cats: Attitudes and Practices Among Thai Veterinarians

Paracetamol add-on treatment for perioperative pain management in dogs undergoing single-site thoracolumbar hemilaminectomy: a prospective clinical study

In this prospective, double-blinded, randomized, clinical trial, it was evaluated whether paracetamol, as an adjunct to NSAID and opioid analgesia, might limit the requirements for intraoperative fentanyl and postoperative methadone administration in dogs undergoing a singlesite thoracolumbar hemilaminectomy for surgical treatment of an intervertebral disc extrusion. Twelve client-owned dogs were randomly assigned to two multimodal analgesia groups: NSAID + paracetamol group (group NP) and NSAID + placebo group (group N). Intraoperative analgesic assessment was based on the clinical evaluation of a nociceptive response, whereas postoperative analgesic assessment was determined by using the short form of the Glasgow Composite Pain Scale. No statistically significant difference was found in both groups for the intraoperative need for fentanyl (P = 0.18). The probability of having to administer rescue analgesia postoperatively was significantly higher in group N than in group NP (P = 0.01). For both groups, there were no serious side effects reported, nor was any significant difference found between both groups regarding the occurrence of side effects (P = 0.55). Despite multimodal perioperative pain management consisting of a full μ-agonist opioid, a NSAID and paracetamol, intraoperative rescue analgesia was still required, although the need for postoperative opioid based analgesia was significantly lower in group NP.

Therapeutic efficacy and pharmacokinetics of liposomal-cannabidiol injection: a pilot clinical study in dogs with naturally-occurring osteoarthritis.

Osteoarthritis is a common disease in dogs resulting in chronic pain and decreased wellbeing. Common analgesics such as non-steroidal anti-inflammatories may fail to control pain and can produce major adverse effects. Study objectives were to evaluate pharmacokinetics, therapeutic efficacy, and safety of subcutaneous liposomal-cannabidiol (CBD) as an additional analgesic therapy in dogs suffering from naturally-occurring osteoarthritis. Six such dogs were recruited following ethics approval and owner consent. Dogs were administered a single subcutaneous injection of 5 mg/kg liposomal-CBD. Plasma concentrations of CBD, blood work, activity monitoring collar data, wellbeing questionnaire (owners) and pain scoring (veterinarian) were performed at baseline and monitored up to six weeks following intervention. Data overtime were compared with baseline using linear-regression mixed-effects. P-value was set at 0.05. CBD plasma concentrations were observed for 6 weeks; median (range) peak plasma concentration (Cmax) was 45.2 (17.8-72.5) ng/mL, time to Cmax was 4 (2-14) days and half-life was 12.4 (7.7-42.6) days. Median (range) collar activity score was significantly increased on weeks 5-6; from 29 (17-34) to 34 (21-38). Scores of wellbeing and pain evaluations were significantly improved at 2-3 weeks; from 69 (52-78) to 53.5 (41-68), and from 7.5 (6-8) to 5.5 (5-7), respectively. The main adverse effect was minor local swelling for several days in 5/6 dogs. Liposomal-CBD administered subcutaneously produced detectable CBD plasma concentrations for 6 weeks with minimal side effects and demonstrated reduced pain and increased wellbeing as part of multimodal pain management in dogs suffering from osteoarthritis. Further placebo-controlled studies are of interest.

The role of cannabinoids in pain modulation in companion animals.

The use of cannabinoids in both veterinary and human medicine is controversial for legal and ethical reasons. Nonetheless, the availability and therapeutic use of naturally occurring or synthetic phytocannabinoids, such as Δ9-tetrahydrocannabidiol and cannabidiol, have been the focus of attention in studies regarding their medical uses. This review aims to examine the role of cannabinoids in pain modulation by analyzing scientific findings regarding the signaling pathways of the endocannabinoid system and discussing the analgesic effects of synthetic cannabinoids compared to cannabinoid extracts and the extent and involvement of their receptors. In animals, studies have shown the analgesic properties of these substances and the role of the cannabinoid binding -1 (CB1) and cannabinoid binding -2 (CB2) receptors in the endocannabinoid system to modulate acute, chronic and neuropathic pain. This system consists of three main components: endogenous ligands (anandamide and 2-arachidonoylglycerol), G protein-coupled receptors and enzymes that degrade and recycle the ligands. Evidence suggests that their interaction with CB1 receptors inhibits signaling in pain pathways and causes psychoactive effects. On the other hand, CB2 receptors are associated with anti-inflammatory and analgesic reactions and effects on the immune system. Cannabis extracts and their synthetic derivatives are an effective therapeutic tool that contributes to compassionate pain care and participates in its multimodal management. However, the endocannabinoid system interacts with different endogenous ligands and neurotransmitters, thus offering other therapeutic possibilities in dogs and cats, such is the case of those patients who suffer from seizures or epilepsy, contact and atopic dermatitis, degenerative myelopathies, asthma, diabetes and glaucoma, among other inflammatory diseases. Moreover, these compounds have been shown to possess antineoplastic, appetite-stimulating, and antiemetic properties. Ultimately, the study of the endocannabinoid system, its ligands, receptors, mechanism of action, and signaling, has contributed to the development of research that shows that hemp-derived and their synthetic derivatives are an effective therapeutic alternative in the multimodal management of pain in dogs and cats due to their ability to prevent peripheral and central sensitization.

Meloxicam is the Primary Choice of Analgesic for Dogs and Cats; A Cross-Sectional Clinical Study in Bangladesh

A cross-sectional clinical survey was conducted on 262 veterinarian participants practicing in Bangladesh with the aim of the current practice of pain management in dogs and cats. The veterinarians were interviewed physically or in online communication with a structured questionnaire. Demographic data of the veterinarians revealed that the majority of them are young males and freshly graduated who use their academic knowledge during practice. The findings of the study also demonstrated that meloxicam is the primary choice of pain management in dogs 66.79% and cats 52.67%. Ketoprofen is the second most choice in both orthopedic and muscular injuries. Among the steroids and opioids categories, dexamethasone and tramadol are recorded respectively as the first choice. Dexamethasone is the primary choice where the pain is the worst. The usual duration of analgesic therapy recorded is less than three days. In most cases, veterinarians suggest H2 blockers in association with meloxicam and ketoprofen to reduce adverse effects. Side effects following analgesic therapy observed are vomition and diarrhea. The current study reviewed the present scenario of analgesics use in dogs and cats in Bangladesh. Further studies are required involving more participants, detailed information on cases, and response to analgesic therapy.

A survey study on the recognition and treatment of pain in dogs and cats by Slovenian veterinarians

ObjectiveTo obtain information on pain management in dogs and cats by Slovenian veterinarians, and to compare it with reports from other countries. Study designProspective online survey. MethodsThe questions were uploaded using open source survey software and pertained to demographic data, self-evaluation of acquired and current knowledge, attitude towards pain and evaluation of actual knowledge, assessment of chronic and acute pain and pain due to surgery or medical conditions, and the use of analgesics. Descriptive statistics were used to summarize frequency distribution. Wilcoxon signed rank test, Mann-Whitney U test and Spearman’s rho were applied where appropriate. ResultsThe response rate was 11%. From 680 registered members of the Veterinary Chamber of Slovenia, 73 veterinarians completed the survey. Most of the respondents were women (71.2%) working in small (60.3%) or mixed (21.9%) animal practices. A more recent year of graduation was positively correlated to the self-reporting of knowledge acquired during undergraduate studies (rs = 0.339, p = 0.003) and to current knowledge about the topic (rs = 0.293, p = 0.012). Cats were assigned higher scores than dogs for signs of acute (p < 0.001) pain. Female respondents assigned higher scores than male respondents for chronic pain in dogs. Dogs were assigned higher pain scores than cats for surgical procedures and medical conditions. The most frequently used non-steroidal anti-inflammatory drugs (NSAIDs) in dogs and cats were meloxicam and carprofen, and butorphanol was the most commonly used opioid. The choice of NSAID was influenced by perceived effectiveness, experience with use and anti-inflammatory effect. Opioid use was influenced by experience with use and perceived effectiveness. Conclusions and clinical relevanceSlovenian veterinarians acknowledged the importance of pain management as reported for other European countries. However, the use of multimodal analgesia is limited, and inadequacies remain in the pain management of cats.

Short-term efficacy of epidural pain management in dogs undergoing cystoscopy.

BackgroundThe effects of epidural anesthesia in dogs undergoing cystoscopy are unknown.ObjectiveTo investigate the effect of epidural analgesia on postcystoscopy pain in dogs.AnimalsTwenty‐six dogs undergoing routine cystoscopy for lower urinary tract disease.MethodsProspective, randomized, blinded observational study. Dogs were assigned either to a treatment group that received epidural anesthesia (preservative free morphine sulfate, 0.09 mg/kg; 1% ropivacaine, 0.2 mg/kg; total volume delivered, 1 mL/4.5 kg of body weight to a maximum of 10 mL; n = 9) or to a nonepidural control group (n = 13). Vital signs were monitored for 24 hours, and sedation and pain scores, behavioral assessments, and presence or absence of complications was evaluated for 5 days postprocedure.ResultsAll dogs tolerated the epidural without complications. Four dogs were removed from the study because of status unblinding, lack of patient cooperation, or incomplete follow‐up. No significant differences were noted in postprocedural pain scores in dogs that received epidural analgesia. Significant differences in postprocedural pain scores were noted in the nonepidural control group. No significant differences were noted in vital signs, behavioral assessments, or the proportion of dogs with a 50% increase in pain scores between the epidural and nonepidural groups.Conclusions and Clinical ImportanceEpidural anesthesia was well‐tolerated. Dogs not receiving the epidural had poor postprocedural pain control. A consistent benefit for the epidural vs nonepidural group could not be identified. Additional studies are required to better assess the impact and efficacy of epidural anesthesia for cystoscopic procedures.

Sprayed intraperitoneal and incisional lidocaine reduces early postoperative pain after ovariohysterectomy in dogs

In the present study, it was aimed to investigate the effect of intraperitoneal and incisional sprayed lidocaine on postoperative stress, oxidative stress and pain in dogs undergoing ovariohysterectomy. The control group (n=12) received intraperitoneal and incisional sprayed 0.9 % NaCl, whereas the preparation of lidocaine (8.8 mg/kg) with the equal volume of 0.9 % NaCl following calculation of the individual doses was sprayed in the experiment group (n=12). Modified Melbourne pain assessment was performed before sedation (T), at the end of surgery (T0), 30 minutes after surgery (T½) and at 1 (T1), 2 (T2), 4 (T4) and 6 (T6) hours after the end of surgery. Venous blood samples were collected to measure the concentrations of serum cortisol, total oxidant status (TOS) and total antioxidant status (TAS) at related times. Oxidative stress index (OSI) was calculated by the determination of the rate of TOS/TAS. The concentrations of cortisol, TAS and OSI did not show any significant difference between groups (p > 0.05). The concentration of TOS was the highest at T1 in the experiment group (p<0.05). The pain scores in the experiment group were lower (p<0.05) than those detected at T2 (p<0.05), T4 (p<0.01) and T6 (p<0.01) in the control group. In conclusion, it was stated that the treatment of intraperitoneal and incisional sprayed lidocaine is effective on postoperative pain management in dogs undergoing ovariohysterectomy.

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

ObjectiveTo evaluate the effects of nalbuphine, butorphanol and morphine combined with acepromazine on intraoperative and early postoperative pain management in dogs anesthetized for ovariohysterectomy. Study designProspective, randomized blinded clinical study. AnimalsA total of 48 healthy female dogs of different breeds, aged 1–6 years, weighing (mean ± standard deviation) 14.5 ± 4.8 kg. MethodsDogs 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. ResultsAt 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 relevanceAt 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.

Postoperative Analgesic Effects of Laserpuncture and Meloxicam in Bitches Submitted to Ovariohysterectomy.

Background: This prospective, randomised and blind study investigated the efficacy of laserpuncture for postoperative pain management in dogs. Method: Sixteen bitches were sedated with acepromazine and randomly treated before ovariohysterectomy with meloxicam 0.2 mg·kg−1 intramuscular or laserpuncture (wavelength 904 mm, frequency 124 Hz, potency 10 Joules, 100 s in each acupoint). Anaesthesia was performed with propofol, isoflurane/O2, and fentanyl. The Glasgow Composite Measure Pain Scale (GCMPS) and Dynamic Interactive Visual Analog Scale (DIVAS) were used to evaluate postoperative pain before and for 24 h after surgery. Morphine was administrated as rescue analgesia when pain scores were ≥3.33 (GCMPS). Differences between treatments, time points, and amount of rescue analgesia between groups were investigated by the Mann–Whitney test and the area under the curve (AUC) for GCMPS, Friedman, and Chi-squared tests, respectively (p < 0.05). Results: Dogs treated with laserpuncture presented lower GCMPS AUC for 24 h and lower GCMPS scores at 2 and 4 h postoperatively (p = 0.04). Three dogs treated with meloxicam required postoperatively rescue analgesia against none treated with laserpuncture. Conclusions: In this preliminary study, laserpuncture mitigated postoperative pain in dogs following ovariohysterectomy, and the technique is a promising adjunct to perioperative pain management in dogs undergoing soft tissue surgery.

Efficacy of intravenous phenylbutazone for pain management in dogs undergoing ovariohysterectomy

The aim of the present study was to evaluate the efficacy and analgesic duration of single dose of PBZ administered the IV route immediately before induction of anesthesia in dogs undergoing elective OVH. Eight-teeen sexually intact female dogs (weiging between 4.5 and 28 kg, and 1 to 8 yrs of age) referred for OVH procedure from a local shelter at regular intervals over 4 months were included in the study. The dogs were administered PBZ on the basis of their respective treatment group (20 mg/kg, IV administration) immediately before anesthetic induction. For the IV treatment, PBZ was administered over a period of one minute. Time of completion of PBZ administration was designed as time 0. In control group, 0.9% NaCl was administered IV as over a period of one minute. Throughout the study, pre and postoperative pain was assessed at baseline (before induction of anesthesia) and then at 0.5, 1, 2, 3, 8, and 24 hrs after the surgery. Group IV had significantly lower CMPS-SF scores than the control group at the 0.5, 1, 2, 3, and 8 hour postoperative periods. In conclusion, a single dose of PBZ administered via the IV route before surgery may be particularly beneficial for acheiving reasonable perioperative analgesia, but not in postoperative period.

A systematic review of analgesia practices in dogs undergoing ovariohysterectomy

Aim:This was a systematic review conducted to evaluate the analgesic drugs and techniques used in the management of pain in dogs undergoing ovariohysterectomy.Materials and Methods:Systematic searches in PubMed, Google Scholar, and ScienceDirect were conducted for peer-reviewed articles written in English and published from 1995 to 2015. The key search words were dogs, ovariohysterectomy, pain, and analgesics. This was followed by a manual search of the references within the primary data sources. Inclusion and exclusion of studies and data extraction were performed independently by two reviewers. All randomized studies evaluating the effects of analgesics during ovariohysterectomy in dogs were included.Results:A total of 31 trials met the criteria and were, therefore, included in the study. Data on the type of analgesic drugs used, the technique of administration, and the need for rescue analgesia were extracted from the papers. Individual analgesic protocols were used in 83.9% of the studies compared to multimodal drug therapy, which was used in 16.1% of the studies. Opioids were used in 39.0% of studies, nonsteroidal anti-inflammatory drugs (NSAIDs) in 19.4%, a combination of NSAIDs and opioids in 19.4%, local analgesics in 6.5%, and acupuncture in 3.2% of the studies. Drug administration was done using three approaches that included pre-operative (64.5%), post-operative (22.6%) as well as combined pre- and post-operative approach (12.9%). In 77.4% of the studies, administration of analgesics was done once, while in 12.9%, it was done as a 72-h post-operative course. 24-h and 48-h courses of post-operative pain therapy were done in 6.5% and 3.2% of the studies, respectively. About 57% of the dogs in the control groups required rescue analgesia as compared to 21.6% in the single and 11.3% in multimodal drug therapy groups. The requirement for rescue analgesics was highest in dogs treated using acupuncture (43.8%) and lowest in dogs treated using NSAID-opioid combination (8.6%). Fewer dogs among those that received pain medication preoperatively and postoperatively required rescue analgesia compared to those in groups given drugs before and after surgery only. More dogs (26.4%) among those given analgesics only once postoperatively required rescue analgesia as compared to those that received analgesics daily for 72 h (4.4%).Conclusions:This study provides evidence that opioids are the mainstream analgesic drugs used in managing acute post-operative pain in dogs’ post-ovariohysterectomy. In addition, multimodal drug therapy, particularly, NSAID-opioids combination is more effective for pain management than single drug administration. Administering analgesics both before and after surgery is associated with better outcomes and so is a protracted course of post-operative pain therapy. Although these practices should be encouraged, controlled studies should be conducted to conclusively determine the best practices for pain management in dogs undergoing ovariohysterectomy.

Comparison of fentanyl and hydromorphone constant rate infusions for pain management in dogs in an intensive care unit

ObjectiveTo compare the efficacy and quality of analgesia provided by constant rate infusions (CRIs) of hydromorphone and fentanyl in dogs in the intensive care unit (ICU). Study designProspective, randomized, blinded, clinical trial. AnimalsA total of 29 client-owned dogs. MethodsDogs prescribed a μ-opioid agonist infusion for postsurgical or medical pain were randomized to be administered either hydromorphone (0.025 or 0.05 mg kg−1 bolus, followed by a 0.03 mg kg−1 hour−1 infusion) or fentanyl (2.5 or 5 μg kg−1 bolus, followed by a 3 μg kg−1 hour−1 infusion). The technical staff and clinicians were blinded as to which drug was administered. Pain scores, using the Colorado State University Canine Acute Pain Scale, sedation scores and nausea scores were assigned at regular intervals and compared between groups. Dose escalation and de-escalation of the study drug were performed according to set protocols. Adverse clinical signs and all other medications administered were recorded and compared between groups. The study drug was discontinued if the animal remained painful despite dose escalations, or if adverse effects were noted. ResultsThe pain scores were of low magnitude and were not significantly different between groups. The use of concurrent analgesia, sedation/anxiolytic medications and antacid/antiemetic medications was not different between groups. Sedation and nausea scores were not statistically different between groups. Conclusions and clinical relevanceHydromorphone and fentanyl CRIs appear to be equally effective for adequate pain relief in dogs, with no significant differences in adverse effects. Therefore, either drug may be chosen for control of postsurgical or medical pain in an ICU setting.

A prospective study of breed differences in the thermal pain sensitivity of dogs

ObjectiveTo compare the thermal nociceptive thresholds (TNTs) of dogs from three working/sport breeds. Study designExperimental prospective study. AnimalsThirty healthy adult dogs of mixed age, sex and reproductive status, 10 of each of three breeds: Harrier Hound, Greyhound and New Zealand Huntaway. MethodsOn one day of each week for 4 weeks, unrestrained dogs were tested six times. TNTs were measured using a remotely activated device comprising a thermode attached to the thoracic limb, controlled by a microprocessor attached to the animal. Latency to exhibit behaviour indicative of nociception after initiation of heating and the temperature of the thermode at the point of behavioural response were measured. Linear mixed-effects models were fitted to the data, with dog included as a random effect, initial thermode temperature as a covariate and day, week and breed as fixed effects. ResultsInitial thermode temperature significantly affected dogs’ latency to respond (p < 0.001). Breed had a significant effect on both latency to respond and response temperature. Huntaways took longer to respond than Harriers or Greyhounds. For example, when the initial thermode temperature was 30 °C, Huntaways took 39.0 seconds to respond compared with 35.8 seconds for Harriers and 36.8 seconds for Greyhounds. Huntaways also responded at higher temperatures (mean±standard deviation: Huntaways 49.7±1.3 °C, Harriers 48.4±1.6 °C and Greyhounds 48.7±1.6 °C). Conclusions and clinical relevanceHuntaways appeared to be less sensitive to thermal pain than the other breeds. Such information could be used by researchers and clinicians to better understand the generalizability of data gathered from a specific breed to the wider canine population or to tailor more effective pharmacological approaches to pain management in dogs.

Chronic pain management in dogs and cats

Chronic pain is difficult to treat and quantify, even in people. However, this does not mean that it should not be considered when examining veterinary patients. As veterinary medicine progresses,...

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...

Gabapentin as an adjuvant for postoperative pain management in dogs undergoing mastectomy.

This study aimed to evaluate the analgesic efficacy of gabapentin as an adjuvant for postoperative pain management in dogs. Twenty dogs undergoing mastectomy were randomized to receive perioperative oral placebo or gabapentin (10 mg/kg). All dogs were premedicated with intramuscular acepromazine (0.03 mg/kg) and morphine (0.3 mg/ kg). Anesthesia was induced with propofol (4 mg/kg) intravenously and maintained with isoflurane. Intravenous meloxicam (0.2 mg/kg) was administered preoperatively. Postoperative analgesia was evaluated for 72 hr. Rescue analgesia was provided with intramuscular morphine (0.5 mg/kg). Dogs in the Placebo group received significantly more morphine doses than the Gabapentin group (P=0.021), despite no significant differences in pain scores. Perioperative gabapentin reduced the postoperative morphine requirements in dogs after mastectomy.

Evaluation of preemptive dexketoprofen trometamol effect on blood chemistry, vital signs and postoperative pain in dogs undergoing ovariohysterectomy.

To investigate the postoperative analgesic effects of preemptive dexketoprofen trometamol in dogs subjected to ovariohysterectomy (OHE). Seventeen adult bitches of various breeds were used in this study. The dogs were randomly allocated into of two groups. Subjects in the dexketoprofen trometamol (DEX) group (n=10), received intravenous (i.v.) dexketoprofen trometamol, 1 mg/kg, 15 minutes before premedication, while those assigned to the control (C) group (n=7) were given no analgesics prior to premedication. Pain level was assessed by two researchers before the administration of anaesthesia (15 minutes before start) and 0, 1, 2, 4 and 6 hours after surgery. A modified University of Melbourne Pain Scale (UMPS) was used to evaluate pain in both groups. Serum cortisol level changed from 0 to 1 h and from 0 to 1 to 4 h were compared between the groups; the increase in the C group was statistically significant. The modified UMPS was applied to both groups at baseline and postoperative 1, 2, 4 and 6 h. According to this test, the values for DEX were significantly lower than controls at 4 and 6 h (p<0.001). Stable vital signs with unchanged biochemical parameters on dexketoprofen administration are a promising finding. The clinical advantage shown by the pain scale difference and the low serum cortisol levels should qualify dexketoprofen for preemptive pain management in dogs (Tab. 5, Fig. 2, Ref. 30).

Electroencephalographic changes associated with antinociceptive actions of lidocaine, ketamine, meloxicam, and morphine administration in minimally anaesthetized dogs.

Effects of ketamine and lidocaine on electroencephalographic (EEG) changes were evaluated in minimally anaesthetized dogs, subjected to electric stimulus. Six dogs were subjected to six treatments in a crossover design with a washout period of one week. Dogs were subjected to intravenous boluses of lidocaine 2 mg/kg, ketamine 3 mg/kg, meloxicam 0.2 mg/kg, morphine 0.2 mg/kg and loading doses of lidocaine 2 mg/kg followed by continuous rate infusion (CRI) of 50 and 100 mcg/kg/min, and ketamine 3 mg/kg followed by CRI of 10 and 50 mcg/kg/min. Electroencephalogram was recorded during electrical stimulation prior to any drug treatment (before treatment) and during electrical stimulation following treatment with the drugs (after treatment) under anaesthesia. Anaesthesia was induced with propofol and maintained with halothane at a stable concentration between 0.85 and 0.95%. Pretreatment median frequency was evidently increased (P < 0.05) for all treatment groups. Lidocaine, ketamine, and morphine depressed the median frequency resulting from the posttreatment stimulation. The depression of median frequency suggested evident antinociceptive effects of these treatments in dogs. It is therefore concluded that lidocaine and ketamine can be used in the analgesic protocol for the postoperative pain management in dogs.

PetSavers funds pain research

Jo Murrell of the University of Bristol asks if oral opioids are effective in the management of acute pain in dogs.