Investigating the effect of anxiety on pain scores in dogs

ObjectiveTo investigate the relationship between anxiety and pain scores using the Glasgow Composite Measure Pain Scale–Short Form (CMPS-SF) in dogs.StudyProspective observational study.AnimalsA group of 18 dogs undergoing surgical management of stifle disease.MethodsPreoperatively dogs were scored using the CMPS-SF, the anxiety behaviour-based Reactivity Evaluation Form (REF), a Visual Analogue Scale (VAS) for anxiety and a sedation score. Assessments of pain, anxiety and sedation were repeated approximately 2–6 hours postoperatively. Dogs were divided into groups based on preoperative REF (‘Low REF’ and ‘High REF’), and VAS scores (‘Low VAS’ and ‘High VAS’). Scores (CMPS-SF, REF, VAS and sedation) were compared between groups using Mann–Whitney U tests. Preoperative and postoperative CMPS-SF, REF and VAS scores were compared using Wilcoxon signed-rank tests. Relationships between anxiety and CMPS-SF scores were assessed using a Spearman rank correlation coefficient. Scores are presented as median (range). A p value of < 0.05 was considered significant.ResultsWhen divided based on REF, CMPS-SF scores did not differ between groups preoperatively [Low REF: 2 (0–3), High REF: 2 (1–3); p = 0.509] or postoperatively [Low REF: 3 (2–5), High REF: 3 (2–5); p = 0.624]. When divided based on VAS, CMPS-SF scores did not differ between groups preoperatively [Low VAS: 2 (0–2), High VAS: 2 (1–3); p = 0.215] or postoperatively [Low VAS: 3 (2–5), High VAS: 3 (2–5); p = 1]. Postoperative REF [pre: 4.5 (2–8), post: 5 (4–10); p = 0.0105] and CMPS-SF scores [pre: 2 (0–3), post: 3 (2–5); p = 0.0318] increased significantly compared with preoperative scores.Conclusions and clinical relevanceNo apparent relationship exists between baseline anxiety levels and CMPS-SF scores. Understanding the influence of anxiety when using the CMPS-SF is important when assessing pain in dogs. Anxiety and pain may increase postoperatively in dogs undergoing orthopaedic surgery.     

Effect of intraperitoneal or incisional bupivacaine on pain and the analgesic requirement after ovariohysterectomy in dogs

ObjectiveTo compare the effect of intraperitoneal (IP) or incisional (INC) bupivacaine on pain and the analgesic requirement after ovariohysterectomy in dogs.Study designProspective, randomized clinical study.AnimalsThirty female dogs undergoing ovariohysterectomy (OHE).MethodsDogs admitted for elective OHE were anesthetized with acepromazine, butorphanol, thiopental and halothane. Animals were randomly assigned to one of three groups (n = 10 per group). The treatments consisted of preincisional infiltration with saline solution (NaCl 0.9%) or bupivacaine with epinephrine and/or IP administration of the same solutions, as follows: INC and IP 0.9% NaCl (control group); INC 0.9% NaCl and IP bupivacaine (5 mg kg^?1, IP group); INC bupivacaine (1 mg kg^?1) and IP 0.9% NaCl (INC group). Postoperative pain was evaluated by a blinded observer for 24 hours after extubation by means of a visual analog scale (VAS) and a numeric rating scale (NRS). Rescue analgesia (morphine, 0.5 mg kg^?1, IM) was administered if the VAS was >5/10 or the NRS >10/29.ResultsAt 1 hour after anesthesia, VAS pain scores were [medians (interquartile range)]: 6.4 (3.1–7.9), 0.3 (0.0–2.6) and 0.0 (0.0–7.0) in control, IP and INC groups, respectively. VAS pain scores were lower in the IP compared to the control group. Over the first 24 hours, rescue analgesia was administered to 7/10, 5/10 and 3/10 dogs of the control, INC and IP groups, respectively. Total number of dogs given rescue analgesia over the first 24 hours did not differ significantly among groups.Conclusions and clinical relevanceIntraperitoneal bupivacaine resulted in lower pain scores during the first hour of the postoperative period and there was a trend towards a decreased need for rescue analgesia after OHE in dogs.     

Analgesic efficacy of intra‐articular morphine in experimentally induced radiocarpal synovitis in horses

ObjectiveTo compare the analgesic effect of intra-articular (IA) and intravenous (IV) morphine in horses with experimentally induced synovitis.AnimalsEight adult horses.Study designRandomized, observer blinded, double dummy trial with sequential crossover design.MethodsRadiocarpal synovitis was induced by IA injection of lipopolysaccharide on two occasions separated by a 3-week washout period. In one study period horses received treatment IA; morphine IA (0.05 mg kg^?1) plus saline IV and in the other study period they received treatment IV; saline IA plus morphine IV (0.05 mg kg^?1). Lameness and pain were evaluated repeatedly by two observers throughout each of the two 168-hour study periods. Pain was evaluated by use of a visual analogue scale of pain intensity (VAS) and a composite measure pain scale (CMPS). Comparison of treatments was performed by analysis of variance with repeated measurements. Significance level was set to p ≤ 0.05. Inter-observer agreement and agreement between the VAS and CMPS was assessed by use of the Bland–Altman method.ResultsIntra-articular injection of LPS elicited a marked synovitis resulting in lameness and pain. IA morphine resulted in significantly less lameness than IV morphine (p = 0.03). CMPS (p = 0.09) and VAS (p = 0.10) pain scores did not differ significantly between treatments. Inter-observer agreement of the CMPS was classified as good, but only fair for the VAS. Agreement between the two pain scales was considered fair.Conclusions and clinical relevanceAn analgesic effect of IA morphine was demonstrated by significantly reduced lameness scores. The results support the common practice of including IA morphine in a multimodal analgesic protocol after arthroscopic surgery, although further studies in clinical cases are needed. The employed CMPS had good reproducibility, and was easy to use, but may have limited sensitivity at mild intensity pain.     

Tramadol plus metamizole combined or not with anti‐inflammatory drugs is clinically effective for moderate to severe chronic pain treatment in cancer patients

ObjectiveTo test the effectiveness and safety of tramadol plus metamizole combined or not with a non-steroidal anti-inflammatory drug (NSAID) for treating moderate to severe chronic neoplastic pain in dogs, and its impact on quality of life (QL).Study designProspective, uncontrolled, open-label, clinical study.AnimalsSixty nine client-owned dogs with multiple forms of cancer and visual analog scale (VAS) pain score ≥40 after receiving NSAIDs for at least 7 days.MethodsThe MN group received metamizole + NSAID, MNT group received metamizole + NSAID + tramadol and MT group received metamizole + tramadol. Pain was scored by the 0 to 100 mm VAS (0 = no pain, 100 = worst pain) and analgesic therapy was considered effective if 25 mm differences in VAS scores were observed between day 0 and the follow ups. The QL was evaluated according to a 0 to 36 scoring method for dogs (0 = worst, 36 = best) and side effects were recorded. Data were registered at day 0 (baseline) and at the first and second follow ups (7 and 14 days after day 0, respectively).ResultsThe MN group had less analgesia at day 7 (25%) and day 14 (42%) than MNT (59%, p = 0.0274; 76%, p = 0.0251, respectively) and MT groups (69%, p = 0.0151; 81%, p = 0.0341, respectively). The QL scores were lower in the MN group at the first (score 23) and second follow up (score 26) than in MNT (27, p = 0.0847; 30, p = 0.0002) and MT (28, p = 0.0384; 31, p = 0.0001) groups. Side effects were more commonly observed in the MN group (87%) than in MNT (24%, p < 0.0001) and MT groups (25%, p = 0.0003) at the first follow up.Conclusions and clinical relevanceTramadol plus metamizole combined or not with NSAID were well tolerated and clinically effective to treat moderate to severe pain in dogs with cancer and improved QL.     

Evaluation of the practical clinical use of the Horse Grimace Scale translated into French

ObjectiveTo assess the reliability of a French version of the Horse Grimace Scale (HGSfv).Study designProspective, randomized, clinical study.AnimalsThe operated (OP) group included 13 horses undergoing elective surgery. The positive (PC) and negative control (NC) groups included seven colicking horses and eight exercising sport horses, respectively.MethodsPhotographs were extracted from videos of the horses’ heads. Videos were taken before and immediately after surgery in OP, on arrival of the horse in PC, and at rest in their stalls in NC. Pictures were evaluated by three anaesthetists [Diplomates (DIPs)] and four riders (RIDs) using Horse Grimace Scale translated into French (HGSfv) at two points, 2 weeks apart (E1 and E2). Each evaluator gave each image a score (1–3) for six identified facial action units. The scores given by DIPs and RIDs were compared using a Wilcoxon test. Intra- and inter-evaluator reliability were assessed using Spearman correlation tests (r_s) and intra-class coefficients (ICCs), respectively.ResultsRIDs and DIPs gave significantly higher scores in the PC group than in the NC group [RIDsE1PC 5.0 (4.2–9.8) versus RIDsE1NC 2.2 (0.0–6.5), p = 0.02; RIDsE2PC 5.2 (3.2–9.5) versus RIDsE2NC 2.0 (0.2–5.8), p < 0.01; DIPsE1PC 4.0 (1.3–6.3) versus DIPsE1NC 2.2 (1.0–4.7), p = 0.04; DIPsE2PC 2.7 (1.0–6.0) versus DIPsE2NC 1.0 (0.0–2.3), p = 0.03]. Scores given by RID or DIPs 2 weeks apart were highly correlated [r_s (RIDsE1, RIDsE2) r = 0.86, p < 0.0001] and [r_s (DIPsE1, DIPsE2) r = 0.81 p < 0.0001]. The ICC between RIDs and DIPs in E1 and E2 was 0.94 (0.92–0.95) and 0.91 (0.89–0.93), respectively. The specificity and sensitivity of the HGSfv was 94% and 43%, respectively.Conclusions and clinical relevanceUsing the HGSfv, knowledge of horses rather than specialization in veterinary anaesthesia and analgesia appears to differentiate horses with visceral pain from those assumed to be pain free.     

Effects of fentanyl–lidocaine–ketamine versus sufentanil–lidocaine–ketamine on the isoflurane requirements in dogs undergoing total ear canal ablation and lateral bulla osteotomy

ObjectiveTo compare the isoflurane-sparing effects of sufentanil–lidocaine–ketamine (SLK) and fentanyl–lidocaine–ketamine (FLK) infusions in dogs undergoing total ear canal ablation and lateral bulla osteotomy (TECA–LBO).Study designRandomized blinded clinical study.AnimalsA group of 20 client-owned dogs undergoing TECA–LBO.MethodsIntravenous (IV) administration of lidocaine (3 mg kg^–1) and ketamine (0.6 mg kg^–1) with fentanyl (5.4 μg kg^–1; n = 10; FLK group) or sufentanil (0.72 μg kg^–1; n = 10; SLK group) was immediately followed by the corresponding constant rate infusion (CRI) (lidocaine 3 mg kg^–1 hour^–1; ketamine 0.6 mg kg^–1 hour^–1; either fentanyl 5.4 μg kg^–1 hour^–1 or sufentanil 0.72 μg kg^–1 hour^–1). Anaesthesia was induced with propofol 3–5 mg kg^–1 IV and was maintained with isoflurane. End-tidal isoflurane concentration (Fe′Iso) was decreased in 0.2% steps every 15 minutes until spontaneous movements were observed (treated with propofol 1 mg kg^–1 IV) or an increase of > 30% in heart rate or mean arterial pressure from baseline occurred (treated with rescue fentanyl or sufentanil). Quality of recovery and pain were assessed at extubation using the short-form Glasgow Composite Pain Scale (SF-GCPS), Colorado State University Canine Acute Pain scale (CSU-CAP), and visual analogue scale (VAS). Data were analysed with analysis of variance, t tests, Fisher test and Spearman coefficient (p < 0.05).ResultsFe′Iso decreased significantly in SLK group (45%; p = 0.0006) but not in FLK (15%; p = 0.1135) (p = 0.0136). SLK group had lower scores for recovery quality (p = 0.0204), SF-GCPS (p = 0.0071) and CSU-CAP (p = 0.0273) than FLK at extubation. Intraoperative rescue analgesia and VAS were not significantly different between groups.Conclusions and clinical relevanceCompared with FLK infusion, CRI of SLK at these doses decreased isoflurane requirements, decreased pain scores and improved recovery quality at extubation in dogs undergoing TECA–LBO.     

A comparison of subarachnoid buprenorphine or xylazine as an adjunct to lidocaine for analgesia in goats

ObjectiveTo test the hypothesis that subarachnoid administration of buprenorphine and lidocaine provides more intense and longer lasting perioperative analgesia with less side effects than xylazine and lidocaine in goats.Study designRandomized, blinded, controlled study.Study animals Ten healthy female goats randomly assigned to two groups of five animals each.MethodsAfter sedation with acepromazine (0.1 mg kg^?1) intravenously (IV), lidocaine 2% (0.1 mL kg^?1) combined with either xylazine (0.05 mg kg^?1; Group X) or buprenorphine (0.005 mg kg^?1; Group B) were injected intrathecally at the lumbo-sacral junction prior to stifle surgery. Electrocardiogram, heart rate, direct systolic, mean, and diastolic arterial blood pressures, rectal temperature and arterial blood gases were recorded as were post-operative sedation and pain scores using a visual analogue and numeric rating scale, respectively. Data were analyzed with one-way anova for repeated measures, one-way anova, Friedman's and Kruskal–Wallis tests as necessary (p< 0.05).ResultsSurgery was successfully performed under both analgesia protocols. Total pain and sedation scores were significantly lower in the B as compared with X group from 3–24 hours and 30–120 minutes, respectively after subarachnoid drug administration (SDA). Heart rate and arterial blood pressures decreased post SDA and were consistently lower in X versus B (p< 0.05). In B arterial blood gas parameters did not change post SDA, but in group X PaCO₂ increased slightly within 15 minutes of SDA and remained elevated for at least 3 hours (p< 0.05).ConclusionIn these goats intrathecal administration of buprenorphine and lidocaine produced more profound and longer lasting analgesia with less sedation and hemodynamic and respiratory impairment than xylazine with lidocaine.Clinical relevanceIn these goats undergoing hind limb surgery, subarachnoid buprenorphine/lidocaine offered more intense and longer lasting analgesia than a xylazine/lidocaine combination, with less sedation and impairment of cardiopulmonary function.     

Preliminary survey of the attitudes of Brazilian scientists towards pain management and assessment in animals used in science

ObjectiveTo investigate the current scenario in Brazil regarding pain assessment and control in experimental animals.Study designProspective survey.MethodsA confidential questionnaire was available online and sent by e-mail to Brazilian scientists working with animal experimentation in Brazil. Data collection was conducted from October 2016 to October 2017. The exclusion criteria included blank questionnaires or with <80% completed responses, researchers not performing experiments involving animals and foreign scientists.ResultsA total of 96 questionnaires from 104 respondents were analyzed. The Fisher’s exact test showed a disparity between the proportions of scientists who recognized the importance of analgesia and their application of analgesic techniques in painful procedures (p < 0.0003), and also for the researchers who assumed that experiments inflicted pain and their classification of the degree of invasiveness (p < 0.0001), indicating their insufficient knowledge of these topics. Overall, 77% of institutions did not offer specific training to assess pain in experimental animals, and 24% of respondents had no training to work with animal experimentation. In total, 62% of the studies inflicted pain, 48% of respondents used pain scales, and the drugs administered most frequently for pain management were morphine (44%), meloxicam (43%) and tramadol (37%); 15% of respondents did not include analgesics even though their studies inflicted pain. Commonly used animals were rats (33%), mice (29%) and rabbits (8%).Conclusions and clinical relevanceThe results of this preliminary survey indicated that in Brazil there is a gap in the knowledge and training on pain assessment and management of experimental animals. Therefore, there is a necessity for an educational program to prepare and train scientists to assess and manage pain in laboratory or experimental animals. Further studies using a psychometrically validated survey instrument are warranted.     

Use of a soluble epoxide hydrolase inhibitor as an adjunctive analgesic in a horse with laminitis

HistoryA 4‐year old, 500 kg Thoroughbred female horse diagnosed with bilateral forelimb laminitis and cellulitis on the left forelimb became severely painful and refractory to non‐steroidal anti‐inflammatory therapy (flunixin meglumine on days 1, 2, 3 and 4; and phenylbutazone on days 5, 6 and 7) alone or in combination with gabapentin (days 6 and 7).Physical examinationPain scores assessed independently by three individuals with a visual analog scale (VAS; 0 = no pain and 10 = worst possible pain) were 8.5 on day 6, and it increased to 9.5 on day 7. Non‐invasive blood pressure monitoring revealed severe hypertension.ManagementAs euthanasia was being considered for humane reasons, a decision was made to add an experimental new drug, trans‐4‐{4‐[3‐(4‐Trifluoromethoxy‐phenyl)‐ureido]‐cyclohexyloxy}‐benzoic acid (t‐TUCB), which is a soluble epoxide hydrolase (sEH) inhibitor, to the treatment protocol. Dose and frequency of administration were selected based on the drug potency against equine sEH to produce plasma concentrations within the range of 30 nmol L^?1 and 2.5 μmol L^?1. Pain scores decreased sharply and remarkably following t‐TUCB administration and blood pressure progressively decreased to physiologic normal values. Plasma concentrations of t‐TUCB, measured daily, were within the expected range, whereas phenylbutazone and gabapentin plasma levels were below the suggested efficacious concentrations.Follow upNo adverse effects were detected on clinical and laboratory examinations during and after t‐TUCB administration. No new episodes of laminitis have been noted up to the time of writing (120 days following treatment).ConclusionsInhibition of sEH with t‐TUCB was associated with a significant improvement in pain scores in one horse with laminitis whose pain was refractory to the standard of care therapy. No adverse effects were noticed. Future studies evaluating the analgesic and protective effects of these compounds in painful inflammatory diseases in animals are warranted.     

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

ObjectiveTo investigate the intraperitoneal (IP) administration of ropivacaine or ropivacaine–dexmedetomidine for postoperative analgesia in cats undergoing ovariohysterectomy.Study designProspective, randomized, blinded, positively controlled clinical study.AnimalsA total of 45 client-owned cats were enrolled.MethodsThe 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).ResultsHR 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 relevanceAs 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.     

Effects of detomidine or romifidine during maintenance and recovery from isoflurane anaesthesia in horses

ObjectiveTo evaluate the effects of detomidine or romifidine on cardiovascular function, isoflurane requirements and recovery quality in horses undergoing isoflurane anaesthesia.Study designProspective, randomized, blinded, clinical study.AnimalsA total of 63 healthy horses undergoing elective surgery during general anaesthesia.MethodsHorses were randomly allocated to three groups of 21 animals each. In group R, horses were given romifidine intravenously (IV) for premedication (80 μg kg^–1), maintenance (40 μg kg^–1 hour^–1) and before recovery (20 μg kg^–1). In group D2.5, horses were given detomidine IV for premedication (15 μg kg^–1), maintenance (5 μg kg^–1 hour^–1) and before recovery (2.5 μg kg^–1). In group D5, horses were given the same doses of detomidine IV for premedication and maintenance but 5 μg kg^–1 prior to recovery. Premedication was combined with morphine IV (0.1 mg kg^–1) in all groups. Cardiovascular and blood gas variables, expired fraction of isoflurane (Fe′Iso), dobutamine or ketamine requirements, recovery times, recovery events scores (from sternal to standing position) and visual analogue scale (VAS) were compared between groups using either anova followed by Tukey, Kruskal-Wallis followed by Bonferroni or chi-square tests, as appropriate (p < 0.05).ResultsNo significant differences were observed between groups for Fe′Iso, dobutamine or ketamine requirements and recovery times. Cardiovascular and blood gas measurements remained within physiological ranges for all groups. Group D5 horses had significantly worse scores for balance and coordination (p = 0.002), overall impression (p = 0.021) and final score (p = 0.008) than group R horses and significantly worse mean scores for VAS than the other groups (p = 0.002).Conclusions and clinical relevanceDetomidine or romifidine constant rate infusion provided similar conditions for maintenance of anaesthesia. Higher doses of detomidine at the end of anaesthesia might decrease the recovery quality.     

Pericapsular hip desensitization in dogs: a cadaveric study and case series

ObjectiveTo develop and assess the efficacy of an ultrasound (US)-guided pericapsular hip desensitization (PHD) technique in dogs.Study designProspective, randomized, anatomical study and a case series.AnimalsA total of 30 healthy dogs, eight canine cadavers and seven dogs with hip osteoarthritis.MethodsAfter studying the US anatomy of the medial aspect of the coxofemoral joint and determining an acoustic window to perform an US-guided PHD in healthy dogs, the US-guided PHD was performed bilaterally in canine cadavers. A low [(LV) 0.1 mL kg^–1] and high [(HV) 0.2 mL kg^–1] volume of dye was injected per hip on each cadaver. The staining of the pericapsular nerves was assessed by anatomical dissection, and comparison between LV and HV was assessed using Fisher’s exact test. Then, the US-guided PHD was performed using a triamcinolone–bupivacaine solution in dogs with hip osteoarthritis. Dynamic pain response was assessed before and after injection. The canine brief pain inventory (CBPI) questionnaire was used to assess treatment efficacy and duration.ResultsThe US-guided PHD could be performed by inserting the needle between the iliopsoas muscle and the periosteum of the ilium. The articular branches of the femoral and obturator nerves were stained in all cadavers using both volumes. The main femoral nerve was never stained, but the main obturator nerve was stained in 37.5% and 100% of injections using LV and HV, respectively (p = 0.026). Treated animals showed decreased dynamic pain response after the injection. Compared with baseline, CBPI scores were reduced by ≥ 50% for ≥ 12 weeks in all but one dog.Conclusions and clinical significanceThe US-guided PHD with both 0.1 and 0.2 mL kg^–1 volumes stained the articular branches of the femoral and obturator nerves in canine cadavers and was associated with clinical improvement in dogs with hip osteoarthritis.     

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.     

A prospective,randomized, blinded,placebo-controlled multisite clinical study of bedinvetmab,a canine monoclonal antibody targeting nerve growth factor,in dogs with osteoarthritis

ObjectiveBedinvetmab is a canine monoclonal antibody targeting nerve growth factor. This study evaluated the efficacy and safety of bedinvetmab for alleviation of pain associated with osteoarthritis in dogs.Study designDouble-blind, randomized, multicentre, placebo-controlled study.AnimalsClient-owned dogs (n = 287) with osteoarthritis.MethodsDogs were randomized (1:1) to subcutaneous injection with placebo (saline, n = 146) or bedinvetmab (0.5–1.0 mg kg^–1, n = 141) administered monthly. After 3 months, 89 bedinvetmab-treated dogs that responded positively based on owner and veterinarian assessments were administered up to six additional doses of bedinvetmab in a single-armed open-label continuation phase. The primary efficacy end point was treatment success based on the owner-assessed canine brief pain inventory (CBPI) on day 28. Treatment success was defined as ≥ 1 reduction in pain severity score (0–10) and ≥ 2 in pain interference score (0–10).ResultsPercentage treatment success was significantly greater in the bedinvetmab group than in the placebo group from day 7 through all assessed time points (p ≤ 0.0025). On day 28, 43.5% of dogs achieved treatment success with bedinvetmab compared with placebo (16.9%) (p = 0.0017). Treatment success continued through days 56 (50.8%) and 84 (48.2%) in the bedinvetmab group and was < 25% in the placebo group at all time points. Sustained efficacy was demonstrated in the continuation phase. Adverse health events occurred at similar frequencies in both groups. They were considered typical for a population of dogs with osteoarthritis and not related to study treatment. Treatment with bedinvetmab demonstrated a significant effect on all three components of CBPI—pain interference, pain severity, quality of life.Conclusions and clinical relevanceThis study demonstrated the effectiveness and safety of bedinvetmab administered monthly for up to 9 months at 0.5–1.0 mg kg^–1 for alleviation of pain associated with canine osteoarthritis.     

A prospective,randomized, double-blind,placebo-controlled multisite,parallel-group field study in dogs with osteoarthritis conducted in the United States of America evaluating bedinvetmab,a canine anti-nerve growth factor monoclonal antibody

ObjectiveBedinvetmab, a fully canine anti-nerve growth factor monoclonal antibody, was evaluated in dogs for control of osteoarthritis-related pain in a study conducted to support registration in the USA.Study designRandomized, double-blind, placebo-controlled, multicenter, parallel-group study.AnimalsGeneral practice client-owned dogs with osteoarthritis (n = 272).MethodsDogs were block randomized 1:1 to placebo (saline, n = 137) or bedinvetmab (n = 135; 0.5–1.0 mg kg^–1) administered subcutaneously, once monthly. The primary end point, day 28 Canine Brief Pain Inventory (CBPI) treatment success (TS), required pain severity score (PSS; 0–10) decrease ≥1 and pain interference score (PIS; 0–10) decrease ≥ 2. CBPI TS rates [and number needed to treat (NNT)], change in scores [and standardized effect size (ES)], change in quality of life (QoL) and bedinvetmab half-life were calculated.ResultsSignificant (p < 0.05) improvement with bedinvetmab over placebo occurred (days 28, 42, 56, 84) for CBPI TS. Of cases evaluable for day 28 CBPI TS (placebo, n = 131; bedinvetmab, n = 128), success rates were 36.6% and 47.4%, respectively (p = 0.0410) (NNT, 9.3; PSS and PIS ES, 0.3). CBPI TS increased after the second dose in both groups, plateaued for bedinvetmab at day 42 and decreased for placebo beginning day 84. Day 84 NNT (4.3), PSS (0.4) and PIS (0.5) showed continued improvement with monthly dosing. After the first dose, mean (± standard deviation) bedinvetmab half-life was 19.1 (8.3) days. Adverse events were similar between groups and not considered treatment-related. There was a significant effect of bedinvetmab versus placebo on all CBPI components (PIS, PSS, QoL).Conclusions and clinical relevanceThese results corroborated those previously reported and provide further support of safety and effectiveness of bedinvetmab (0.5–1.0 mg kg^–1) administered subcutaneously at monthly intervals to dogs for control of osteoarthritis-related pain.     

Clinical assessment and grading of back pain in horses

BackgroundThe clinical presentation of horses with back pain (BP) vary considerably with most horse''s willingness to take part in athletic or riding purpose becoming impossible. However, there are some clinical features that are directly responsible for the loss or failure of performance.ObjectivesTo investigate the clinical features of the thoracolumbar region associated with BP in horses and to use some of the clinical features to classify equine BP.MethodsTwenty-four horses comprised of 14 with BP and 10 apparently healthy horses were assessed for clinical abnormality that best differentiate BP from normal horses. The horses were then graded (0–5) using the degree of pain response, muscular hypertonicity, thoracolumbar joint stiffness and overall physical dysfunction of the horse.ResultsThe common clinical features that significantly differentiate horses with BP from non-BP were longissimus dorsi spasm at palpation (78.6%), paravertebral muscle stiffness (64.3%), resist lateral bending (64.3%), and poor hindlimb impulsion (85.7%). There were significantly (p < 0.05) higher scores for pain response to palpation, muscular hypertonicity, thoracolumbar joint stiffness and physical dysfunction among horses with BP in relation to non-BP. A significant relationship exists between all the graded abnormalities. Based on the cumulative score, horses with BP were categorized into mild, mild-moderate, moderate and severe cases.ConclusionsBP in horse can be differentiated by severity of pain response to back palpation, back muscle hypertonicity, thoracolumbar joint stiffness, physical dysfunctions and their cumulative grading score is useful in the assessment and categorization of BP in horses.     

Correlations between acute radiation scores and pain scores in canine radiation patients with cancer of the forelimb

Objective To determine whether there is a correlation between skin acute radiation score (ARS) and pain scores and to determine if skin ARSs can be used to predict future pain scores and increased need for analgesia in dogs undergoing radiation therapy for cancer of the forelimb. Study design Prospective observational study. Animals Seven middle‐aged dogs of various breeds with cancer of the forelimb. Methods Each neoplasm was surgically removed and a histologic diagnosis was obtained. Curative intent radiation therapy was initiated 2½–4½ weeks after surgery. Curative intent radiation therapy was delivered as prescribed. Two trained observers scored the dogs using a visual analog pain scale (VAS), Glasgow composite measure of pain scale, short form (GCMPS) and skin ARS prior to each day’s therapy. Daily scores were averaged and scatter plots were developed. Generalized estimating equation regressions were used to calculate standard error, 95% confidence interval, and p‐values for each relationship. Confidence and prediction bands were plotted. Results A statistically significant correlation between skin ARS and VAS and GCMPS pain scores was identified indicating that as the skin ARS increased so did the pain scores. A general correlation between VAS and GCMPS scores was observed. Early (fraction days 1–6) GCMPS scores were significantly influenced by anxiety behavior unrelated to pain. Skin ARS was found to predict precisely current and future presence of pain, but could only predict a range of potential future pain scores based on the pain management approach in use during this study. Conclusions Skin ARS can provide valuable information for initiating preemptive analgesia and intensifying pain management during curative intent radiation therapy. Daily pain scoring with an acceptable pain scale should be used in conjunction with the skin ARS to improve patient pain management. Clinical relevance Pain is an anticipated consequence of curative intent radiation therapy. Understanding the correlation between pain and skin ARS may facilitate more effective pain management.