Validation of the English version of the UNESP-Botucatu multidimensional composite pain scale for assessing postoperative pain in cats

The impact of using pain scales by untrained students on the decision to provide analgesia to multiple species

OBJECTIVE

To evaluate if students without training assess pain similarly to an expert, and to compare indications for analgesic intervention based on student opinions versus scale scoring.

STUDY DESIGN

Prospective, blind, randomized, cross-sectional study.

ANIMALS

Video recordings of a bull, horse, cat, pig and sheep.

METHODS

First-year veterinary medicine students assessed one video of a horse (n = 44) and one video of a bull (n = 39). Third-year veterinary medicine students assessed one video of a cat (n = 23) and one video of a pig (n = 21). Fourth-year animal science students (n = 16) assessed one video of a sheep. The species assessed by different student classes were determined randomly. Students were unaware of animal history or existing pain assessment and decided whether they would provide analgesia according to their opinion. They then scored each video using species-specific validated pain scales. Scores were compared with those of a board-certified anesthesiologist (expert). Chi-square test was used to compare students and expert.

RESULTS

Students underestimated the expert's score by 8-20%, except for the horse. There was no difference between the analgesic indication according to the assessment of the expert (143/143, 100%) and students (141/143, 98.6%) considering the defined analgesic intervention threshold for each scale (p = 0.478). The indication for analgesic intervention according to students' opinion (116/143, 81.1%) was lower than that according to their scale scores (141/143, 98.6%) (p < 0.0001).

CONCLUSIONS AND CLINICAL RELEVANCE

Students tended to underestimate pain; however, they detected pain that requires analgesic intervention in animals similarly to an expert. The use of scales optimized the indication for providing analgesia when animals were experiencing pain that required analgesic intervention.

Video-based compilation of acute pain behaviours in cats

OBJECTIVES

The aim of this work was to create a video-based compilation of acute pain behaviours in cats as an open-access online resource for training of veterinary health professionals.

METHODS

A database comprising 60 h of video recordings of cats was used. Videos were previously recorded after ethical approval and written client consent forms, and involved cats with different types (eg, medical, surgical, trauma, orofacial) and degrees (eg, from no pain to severe pain) of acute pain, before and after surgery or the administration of analgesia. The database included videos of cats of different coat colours, ages, sex and breeds. Video selection was based on a published ethogram of acute pain behaviours in cats. Videos were selected by one observer (SM) according to their definition and quality, followed by a second round of screening by two observers (SM and PVS). Video editing included a standardised template (ie, watermark and titles).

RESULTS

A total of 24 videos (mean length 33 ± 17 s) with each acute pain-related behaviour described in the ethogram were uploaded to an open-access online video-sharing platform (http://www.youtube.com/@Steagalllaboratory) with an individual hyperlink. Videos were provided with a short description of the behaviour for the public.

CONCLUSIONS AND RELEVANCE

This video-based compilation may promote better training of veterinary health professionals on acute pain assessment while improving feline health and welfare and the understanding of cat behaviours.

Perioperative Analgesic and Sedative Effects of Cannabidiol in Cats Undergoing Ovariohysterectomy

The aim of this study was to evaluate the perioperative analgesic and sedative effects of oral CBD in cats undergoing ovariohysterectomy. Twenty-two cats were assigned to receive either oral cannabidiol oil (2 mg/kg, CBD group, n = 12) or placebo oil (0.1 mL/kg, Placebo group, n = 10) 60 min before the premedication. The anesthetic protocol included dexmedetomidine/meperidine, propofol, and isoflurane. Intravenous fentanyl was given to control cardiovascular responses to surgical stimulation. Pain was assessed at 0.5, 1, 2, 4, 6 and 8 h post-extubation using the UNESP-Botucatu multidimensional composite pain scale and the Glasgow feline composite-measure pain scale. Sedation scores were assessed at the same timepoints and at 15 min after the premedication. Morphine was administered as rescue analgesia. Higher sedation scores were recorded in the CBD group at 15 min after premedication (p = 0.041). Intraoperatively, more cats required fentanyl in the Placebo group than in CBD group (p = 0.028). The pain scores did not differ between groups, except at 0.5 h post-extubation when lower scores were detected in the CBD group (p = 0.003-0.005). Morphine was required in 100% of the animals in both groups. CBD increased preoperative sedation and decreased intraoperative analgesic requirements, with minimal evidence of postoperative analgesic benefits over the placebo.

Comparison of Butorphanol, Methadone, and Pethidine in Combination with Alfaxalone for Premedication in Isoflurane-Anesthetized Cats Undergoing Ovariectomy

The aim of this study was to compare three different anesthetic protocols administered intramuscularly (IM) in cats undergoing elective ovariectomy, while evaluating the quality of sedation, antinociceptive, isoflurane-sparing effect, and analgesia in the intra-operative and post-operative phases. A total of 71 female cats were sedated IM with alfaxalone (3 mg/kg) combined with either butorphanol (0.3 mg/kg), methadone (0.3 mg/kg), or pethidine (5 mg/kg). During surgery, vital parameters were constantly monitored; at the end of the procedure, the quality of recovery was assessed through a specific form and each cat was scored for perceived pain using the UNESP-Botucatu scale for 5 days, and rescue analgesia was provided with buprenorphine IM when indicated. Moreover, differences between two different post-operative resting regimens (hospital kennels vs. home) were also assessed. A significant difference emerged for the amount of IM dexmedetomidine required to achieve an adequate level of sedation for intravenous catheterization, highlighting a greater need in the pethidine group (p = 0.021). There was no significant difference between opioid groups for the requirement of intra-operative rescue analgesia, and the clinical parameters were kept within physiological ranges regardless of the opioid used in premedication. Lastly, differences between the UNESP-Botucatu scores were detected from day 3 to day 5 post-operatively, with lower scores in cats with home resting regimens compared to the hospitalized animals, likely due to the presence of an unfamiliar condition and the absence of a cat-friendly environment.

Real-time and video-recorded pain assessment in beef cattle: clinical application and reliability in young, adult bulls undergoing surgical castration

Bovine pain assessment relies on validated behavioral scales related to normal and pain-related behaviors. This study investigated the reliability and applicability of real-time and video-recorded pain assessment, and their agreement, in young, adult bulls undergoing surgical castration. Ten Nelore and nine Angus bulls underwent general anesthesia and surgical castration. Three-minute real-time observations and simultaneous videos were recorded at - 48 h (M0), before sedation, under fasting (M1), after surgery, 3 h after sternal recumbency (M2), after rescue analgesia (M3) and at 24 h (M4). Animals received morphine (after M2), dipyrone (after M3), and flunixin meglumine after surgical castration (M4). Two trained evaluators assessed real-time (n = 95) and video-recorded time-points (n = 95) using the Unesp-Botucatu Cattle Pain Scale (UCAPS). Both assessment methods inferred 'very good' reliability (≥ 0.81) with minimal bias, however, video-recorded assessment (4.33 ± 2.84) demonstrated slightly higher scores compared to real-time (3.08 ± 2.84). The results from this study suggest that UCAPS can be used in real-time or video-recorded to assess pain and guide analgesic therapy in cattle.

Temporomandibular Joint Gape Angles in Normal and Painful Domestic Felines

The purpose of this study was to determine and compare the gape angles (temporomandibular joint range of motion with mouth opening) of conscious and anesthetized domestic felines and to compare gape angles with and without evidence of oral pain. This prospective study evaluated the gape angle of 58 domestic felines. The cats were grouped into painful (n = 33) and nonpainful cohorts (n = 25) and gape angles were compared during conscious and anesthetized conditions. Gape angles were determined based on measurements of the maximal interincisal distance and lengths of the mandible and maxilla followed by calculation of the law of cosines. The mean feline gape angle (standard deviation) was determined to be 45.3° (8.6°) and 50.8° (6.2°) for conscious and anesthetized felines respectively. There was no significant difference between painful and non-painful feline gape angles during conscious (P = .613) or anesthetized (P = .605) evaluations. There was a significant difference between anesthetized and conscious gape angles (P < .001) for both painful and non-painful cohorts. This study determined the standardized, normal feline temporomandibular joint (TMJ) gape angle in both conscious and anesthetized states. This study suggests that the feline gape angle is not a useful indicator of oral pain. By determining the feline gape angle, which was previously unknown, further evaluation of its utility as a non-invasive clinical parameter for evaluation of restrictive TMJ motions as well as its use for serial evaluations may be pursued.

Applicability, reproducibility, and reliability of the German version of the Glasgow composite measured pain scale - feline during implementation into a small animal clinic

OBJECTIVE

The aim of the study was to evaluate reproducibility and practicality of the German version of the Glasgow composite measured pain scale - feline, during its implementation into a German veterinary hospital.

MATERIAL AND METHODS

The study comprised of 2 parts. Participation of veterinary professionals was voluntary. During part 1, 15 staff members (all rater=AR) with variable clinical experience (nurses, interns, junior clinician, senior clinicians), from 4 disciplines (anesthesia, internal medicine, surgery, neurology), and one main investigator (AC), pain scored 45 diseased cats and 10 healthy cats. Part 2 was an online survey, evaluating the practical experience of participants during part 1 and asking for suggestions to improve the scale and process of pain assessment. For part 1 normal distribution of data was tested by Shapiro-Wilk-Test and histograms. Intrarater and interrater reliability were evaluated by calculating the intraclass-correlation. Statistical analysis of part 2 used descriptive methods.

RESULTS

The interrater reliability was moderate (ICC AR : 0.59) and the intrarater reliability was good (ICC AC : 0.88). The pain scores of cats with medical (AR: 3.06±2.33, AC 3.52±2.34) and surgical disease (AR: 3.78±2.38, AC: 4.02±2.72) showed no significant difference. All healthy cats were classified as "not painful" (AR: 0.77±0.67, AC: 1.09±0.83). Clinical experience of the rater did not significantly influence pain scores. The GCMPS-F was judged as easy to use and as helpful tool for cats with unclear pain conditions.

CONCLUSION

The GCMPS-F had a good acceptance and moderate interrater reliability.

CLINICAL RELEVANCE

Using the German version of the GCMPS-F, veterinary professionals from different disciplines and with different grades of specialisation can reliably assess pain levels in cats without prior extensive training.

A comparison of intra and postoperative analgesic effects of sacrococcygeal and lumbosacral epidural levobupivacaine in cats undergoing ovariohysterectomy

The aim of this study was to compare the intra and postoperative analgesic effects of sacrococcygeal epidural levobupivacaine with those of lumbosacral levobupivacaine in feline ovariohysterectomy. Thirty-six cats were premedicated with intramuscular acepromazine (0.05 mg/kg) and meperidine (6 mg/kg). Anesthesia was induced with intravenous propofol and maintained with isoflurane in oxygen. The cats were randomly assigned one of the three treatments receiving 0.33% levobupivacaine (0.3 mL/kg) into the sacrococcygeal (S-C group, n=12) or lumbosacral (L-S group, n=12) epidural space, or the same volume of 0.9% saline solution into one of the epidural approaches (Control group, n=12). Intraoperatively, cardiorespiratory variables, end-tidal isoflurane concentration (FE´ISO), and fentanyl requirements were recorded. Postoperative pain was assessed by the UNESP (Universidade Estadual Paulista)-Botucatu multidimensional composite pain scale and the Glasgow feline composite measure pain scale up to 8 hr post-extubation. Morphine was administered as rescue analgesia. Overall FE´ISO and fentanyl requirements were lower in the L-S and S-C compared to the Control (P=0.002-0.048, respectively). There was no significant difference in the cardiorespiratory variables during anesthesia, postoperative pain and rescue analgesia among groups. The time to standing after anesthesia was prolonged in the L-S and S-C groups than in the Control (P<0.001). Lumbosacral and sacrococcygeal epidural levobupivacaine resulted in similar decreases in isoflurane requirements and intraoperative fentanyl supplementation in the cats, with no postoperative benefits.

An ethogram of acute pain behaviors in cats based on expert consensus

An improved understanding of behaviors reflecting acute pain in cats is a priority for feline welfare. The aim of this study was to create and validate a comprehensive ethogram of acute pain behaviors in cats that can discriminate painful versus non-painful individuals. An inventory of behaviors (ethogram) with their respective descriptors was created based on a literature review of PubMed, Web of Science and CAB Abstracts databases. The ethogram was divided into ten behavior categories that could be evaluated by duration and/or frequency: position in the cage, exploratory behaviors, activity, posture and body position, affective-emotional states, vocalization, playing (with an object), feeding, post-feeding and facial expressions/features. Thirty-six behaviors were analyzed independently by four veterinarians with postgraduate qualifications in feline medicine and/or behavior as (1) not relevant, (2) somewhat relevant, (3) quite relevant or (4) highly relevant and used for content (I-CVI) and face validity. Items with I-CVI scores > 0.67 were included. Twenty-four behaviors were included in the final ethogram. Thirteen items presented full agreement (i.e., I-CVI = 1): positioned in the back of the cage, no attention to surroundings, feigned sleep, grooming, attention to wound, crouched/hunched, abnormal gait, depressed, difficulty grasping food, head shaking, eye squinting, blepharospasm and lowered head position. Seven descriptors were reworded according to expert suggestions. The final ethogram provides a detailed description of acute pain behaviors in cats after content and face validity and can be applied to the characterization of different acute painful conditions in hospitalized cats.

Development and Validation of the Unesp-Botucatu Goat Acute Pain Scale

We aimed to develop and validate the Unesp-Botucatu goat acute pain scale (UGAPS). Thirty goats (5 negative controls and 25 submitted to orchiectomy) were filmed for 7 min at the time points 24 h before and 2 h, 3 h (1 h after analgesia), and 24 h after orchiectomy. After content validation, according to an ethogram and literature, four blind observers analyzed the videos randomly to score the UGAPS, repeating the same assessment in 30 days. According to the confirmatory factor analysis, the UGAPS is unidimensional. Intra- and interobserver reliability was very good for all raters (Intraclass correlation coefficient ≥85%). Spearman's correlation between UGAPS versus VAS was 0.85 confirming the criterion validity. Internal consistency was 0.60 for Cronbach's α Cronbach and 0.67 for McDonald's ω. The item-total correlation was acceptable for 80% of the items (0.3-0.7). Specificity and sensitivity based on the cut-off point were 99% and 90%, respectively. The scale was responsive and demonstrated construct validity shown by the increase and decrease of scores after surgery pain and analgesia, respectively. The cut-off point for rescue analgesia is ≥3 of 10, with an area under the curve of 95.27%. The UGAPS presents content, criterion, and construct validities, responsiveness, and reliability to assess postoperative pain in castrated goats.

Reliability and Validity of UNESP-Botucatu Cattle Pain Scale and Cow Pain Scale in Bos taurus and Bos indicus Bulls to Assess Postoperative Pain of Surgical Orchiectomy

Pain assessment guides decision-making in pain management and improves animal welfare. We aimed to investigate the reliability and validity of the UNESP-Botucatu cattle pain scale (UCAPS) and the cow pain scale (CPS) for postoperative pain assessment in Bos taurus (Angus) and Bos indicus (Nelore) bulls after castration.

METHODS

Ten Nelore and nine Angus bulls were anaesthetised with xylazine-ketamine-diazepam-isoflurane-flunixin meglumine. Three-minute videos were recorded at -48 h, preoperative, after surgery, after rescue analgesia and at 24 h. Two evaluators assessed 95 randomised videos twice one month apart.

RESULTS

There were no significant differences in the pain scores between breeds. Intra and inter-rater reliability varied from good (>0.70) to very good (>0.81) for all scales. The criterion validity showed a strong correlation (0.76-0.78) between the numerical rating scale and VAS versus UCAPS and CPS, and between UCAPS and CPS (0.76). The UCAPS and CPS were responsive; all items and total scores increased after surgery. Both scales were specific (81-85%) and sensitive (82-87%). The cut-off point for rescue analgesia was >4 for UCAPS and >3 for CPS.

CONCLUSIONS

The UCAPS and CPS are valid and reliable to assess postoperative pain in Bos taurus and Bos indicus bulls.

Measurement properties of pain scoring instruments in farm animals: A systematic review using the COSMIN checklist

This systematic review aimed to investigate the measurement properties of pain scoring instruments in farm animals. According to the PRISMA guidelines, a registered report protocol was previously published in this journal. Studies reporting the development and validation of acute and chronic pain scoring instruments based on behavioral and/or facial expressions of farm animals were searched. Data extraction and assessment were performed individually by two investigators using the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines. Nine categories were assessed: two for scale development (general design requirements and development, and content validity and comprehensibility) and seven for measurement properties (internal consistency, reliability, measurement error, criterion and construct validity, responsiveness and cross-cultural validity). The overall strength of evidence (high, moderate, low, or very low) of each instrument was scored based on methodological quality, number of studies and studies' findings. Twenty instruments for three species (bovine, ovine and swine) were included. There was considerable variability concerning their development and measurement properties. Three behavior-based instruments scored high for strength of evidence: UCAPS (Unesp-Botucatu Unidimensional Composite Pain Scale for assessing postoperative pain in cattle), USAPS (Unesp-Botucatu Sheep Acute Composite Pain Scale) and UPAPS (Unesp-Botucatu Pig Composite Acute Pain Scale). Four instruments scored moderate for strength of evidence: MPSS (Multidimensional Pain Scoring System for bovine), SPFES (Sheep Pain Facial Expression Scale), LGS (Lamb Grimace Scale) and PGS-B (Piglet Grimace Scale-B). Most instruments (n = 13) scored low or very low for final overall evidence. Construct validity was the most reported measurement property followed by criterion validity and reliability. Instruments with reported validation are urgently required for pain assessment of buffalos, goats, camelids and avian species.

Validation of the Unesp-Botucatu pig composite acute pain scale (UPAPS) in piglets undergoing castration

To accurately assess pain and support broadly-based analgesic protocols to mitigate swine pain, it is imperative to develop and validate a species-specific pain scale. The objective of this study was to investigate the clinical validity and reliability of an acute pain scale (UPAPS) adapted for newborn piglets undergoing castration. Thirty-nine male piglets (five days of age, 1.62 ± 0.23 kg BW) served as their own control, were enrolled in the study and underwent castration in conjunction with an injectable analgesic administered one-hour post-castration (flunixin meglumine 2.2 mg/kg IM). An additional 10, non-painful female piglets were included to account for the effect of natural behavioral variation by day on pain scale results. Behavior of each piglet was video recorded continuously at four recording periods (24 h pre-castration, 15 min post-castration, 3 and 24 h post-castration). Pre- and post-operative pain was assessed by using a 4-point scale (score 0-3) including the following six behavioral items: posture, interaction and interest in surroundings, activity, attention to the affected area, nursing, and miscellaneous behavior. Behavior was assessed by two trained blinded observers and statistical analysis was performed using R software. Inter-observer agreement was very good (ICC = 0.81). The scale was unidimensional based on the principal component analysis, all items except for nursing were representative (rs ≥ 0.74) and had excellent internal consistency (Cronbach's alpha ≥ 0.85). The sum of scores were higher in castrated piglets post-procedure compared to pre-procedure, and higher than in non-painful female piglets confirming responsiveness and construct validity, respectively. Scale sensitivity was good when piglets were awake (92.9%) and specificity was moderate (78.6%). The scale had excellent discriminatory ability (area under the curve > 0.92) and the optimal cut-off sum for analgesia was 4 out of 15. The UPAPS scale is a valid and reliable clinical tool to assess acute pain in castrated pre-weaned piglets.

Pain Recognition in Rodents

Available methods for recognizing and assessing pain in rodents have increased over the last 10 years, including the development of validated pain assessment scales. Much of this work has been driven by the needs of biomedical research, and there are specific challenges to applying these scales in the clinical environment. This article provides an introduction to pain assessment scale validation, reviews current methods of pain assessment, highlighting their strengths and weaknesses, and makes recommendations for assessing pain in a clinical environment.

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.

Randomised clinical trial comparing the perioperative analgesic efficacy of oral tramadol and intramuscular tramadol in cats

OBJECTIVES

The aim of this study was to evaluate the analgesic efficacy of oral tramadol in cats undergoing ovariohysterectomy.

METHODS

Twenty-four female domestic cats, American Society of Anesthesiologists class I, aged 4-24 months, were included in this positive controlled, randomised, blinded clinical trial. Cats admitted for ovariohysterectomy were allocated to group oral tramadol (GOT, n = 12) or group intramuscular tramadol (GIMT, n = 12). In GOT, tramadol (6 mg/kg) was given orally 60 mins, and saline was given intramuscularly 30 mins, before induction of anaesthesia. In GIMT, granulated sugar in capsules was given orally 60 mins and tramadol (4 mg/kg) intramuscularly 30 mins before induction of anaesthesia. In both groups, dexmedetomidine (0.007 mg/kg) was given intramuscularly 30 mins before induction of anaesthesia with intravenous propofol. Anaesthesia was maintained with isoflurane in oxygen, and atipamezole (0.037 mg/kg) was given intramuscularly 10 mins after extubation. The UNESP-Botucatu multidimensional composite scale was used to conduct pain assessments before premedication and at 20, 60, 120, 240 and 360 mins post-extubation or until rescue analgesia was given. To compare groups, the 60 min postoperative pain scores and the highest postoperative pain scores were analysed via a two-tailed Mann-Whitney test, and the incidences of rescue analgesia were analysed via a Fisher's exact test; P <0.05.

RESULTS

There was no significant difference between groups for the 60 min (P = 0.68) pain scores. The highest postoperative pain score was higher for GIMT compared with GOT (P = 0.04). Only two cats required rescue analgesia, both from GIMT. The incidence of rescue analgesia was not significantly different between groups (P = 0.46).

CONCLUSIONS AND RELEVANCE

In the present study, preoperative administration of oral tramadol at 6 mg/kg to cats provided adequate analgesia for 6 h following ovariohysterectomy surgery.

Automated recognition of pain in cats

Facial expressions in non-human animals are closely linked to their internal affective states, with the majority of empirical work focusing on facial shape changes associated with pain. However, existing tools for facial expression analysis are prone to human subjectivity and bias, and in many cases also require special expertise and training. This paper presents the first comparative study of two different paths towards automatizing pain recognition in facial images of domestic short haired cats (n = 29), captured during ovariohysterectomy at different time points corresponding to varying intensities of pain. One approach is based on convolutional neural networks (ResNet50), while the other-on machine learning models based on geometric landmarks analysis inspired by species specific Facial Action Coding Systems (i.e. catFACS). Both types of approaches reach comparable accuracy of above 72%, indicating their potential usefulness as a basis for automating cat pain detection from images.

Is training necessary for efficacious use of the Glasgow Feline Composite Measure Pain Scale?

OBJECTIVE

The Glasgow Feline Composite Measure Pain Scale (CMPS-F) is a validated cat pain assessment tool for clinical use. No research has examined how training impacts use of this tool. Thus, we examined whether seminar-style training improves the identification of cat pain when using the CMPS-F. Veterinarians (n = 17) and non-veterinarian staff (n = 33; N = 50) were recruited to participate.

PROCEDURE

Seminars included: i) pre-training use of the CMPS-F to score cat videos with varying degrees of pain; ii) cat pain assessment training; and iii) post-training use of the CMPS-F. Participant CMPS-F ratings were compared to experts' ratings of the same videos. Average CMPS-F scores and analgesic decision ratings were compared pre-and post-training.

RESULTS

Most participants were female non-veterinarian staff who had not heard of the CMPS-F. Participant and expert analgesic decision-making did not differ pre- (P = 1.0) and post-training (P = 0.1). In addition, analgesic decision-making was similar between participants and experts for all but 3/20 videos.

CONCLUSION AND CLINICAL RELEVANCE

Seminar training may not be necessary for efficacious use of the CMPS-F. Further research is needed to explore strategies for improving awareness of cat pain assessment tools and increasing in-clinic use.

Use of mechanical thresholds in a model of feline clinical acute pain and their correlation with the Glasgow Feline Composite Measure Pain Scale scores

OBJECTIVES

The aim of this study was to evaluate the use of mechanical thresholds (MT), measured with the SMALGO (Small Animal ALGOmeter), and to determine whether there was a correlation between MT and Glasgow Feline Composite Measure Pain Scale (CMPS-Feline) scores in cats undergoing ovariohysterectomy.

METHODS

Client-owned cats undergoing flank ovariohysterectomy were recruited. Pain scores for the pre- and postoperative periods were obtained using the CMPS-Feline in each cat by two independent investigators (A and B). Following CMPS-Feline scoring, MT were measured with the SMALGO, in the surgical area, pre- and postoperatively, only by investigator A. Each cat served as its own control for the comparison of pre- and postoperative variables. Reliability statistics were used to assess the level of inter-observer agreement (A vs B) with respect to pre- and postoperative CMPS-Feline scores, while Spearman's correlation statistics were used to analyse the relationship between MT and CMPS-Feline scores.

RESULTS

Twenty-nine cats completed the study. Preoperative MT (340 g [range 108-691]) were significantly higher than postoperatively (233 g [range 19-549]; P = 0.001). CMPS-Feline scores were not found to differ significantly between the preoperative period (2 [range 0-7] for investigator A and 3.2 ± 2.3 for investigator B) and postoperative period (2 [range 0-10] for investigator A and 3 [range 0-8] for investigator B) for either investigator. Reliability statistics revealed that the level of inter-observer agreement with respect to CMPS-Feline was fair for the preoperative assessments but poor for the postoperative evaluations. There was no correlation between MT and CMPS-Feline scores.

CONCLUSIONS AND RELEVANCE

Although there was no correlation with CMPS-Feline scores performed at the same timepoint, MT increased postoperatively vs baseline. Assuming that, despite analgesia, susceptibility of the surgical area to mechanical stimulation would increase after surgery, this finding suggests that MT might be useful to assess feline surgical pain. The poor level of inter-observer agreement with respect to postoperative CMPS-Feline scores highlights the potential limitations of this scale.

Validation of the rabbit pain behaviour scale (RPBS) to assess acute postoperative pain in rabbits (Oryctolagus cuniculus)

Considering the widespread use of rabbits in research that potentially causes pain and discomfort and the limited number of pain assessment validated tools in this species, we aimed to develop and validate a scale of acute postoperative pain in rabbits (RPBS). Footage of 58 rabbits from previous studies were used, recorded at 'baseline' (before orthopaedic and soft tissue surgeries), 'pain' (after surgery), 'analgesia' (after analgesic), and '24h post' (24 hours after surgery). The videos were randomised and assessed twice by four evaluators, within one-month interval between evaluations. After content validation, RBPS was further refined using the criteria from the validation. According to the principal component analysis, RPBS was considered unidimensional. The intra- and inter-observer reliability was excellent (ICC>0.80) for all evaluators. There was a high Spearman's correlation of the RPBS with unidimensional scales (>0.80) and a moderate correlation with the Rabbit Grimace Scale (0.68), confirming criterion validity. According to the mixed linear model, the scale was responsive, shown by the increase in pain scores after surgery. Construct validity was confirmed by known-group approach and internal relationships among items. Adequate item-total correlation (>0.3) was observed for all items, except for the attention to the affected area (0.04). The internal consistency was very good (Cronbach's α coefficient = 0.78; Mcdonald's ω coefficient = 0.83). The cut-off score for rescue analgesia was ≥3, with an area under the curve >0.95, demonstrating a high discriminatory capacity of the instrument. Scores 3 and 4 were within the uncertainty diagnostic zone. Specificity was 87% and sensitivity was 90%. It was concluded that the RPBS presented content, criterion, and construct validities, responsiveness, and reliability to assess acute pain in rabbits submitted to orthopaedic and soft tissue surgeries. The cut-off for rescue analgesia serves as a basis for the administration of analgesics to rabbits submitted to painful procedures.

Multilingual validation of the short form of the Unesp-Botucatu Feline Pain Scale (UFEPS-SF)

Background

Pain is the leading cause of animal suffering, hence the importance of validated tools to ensure its appropriate evaluation and treatment. We aimed to test the psychometric properties of the short form of the Unesp-Botucatu Feline Pain Scale (UFEPS-SF) in eight languages.

Methods

The original scale was condensed from ten to four items. The content validation was performed by five specialists in veterinary anesthesia and analgesia. The English version of the scale was translated and back-translated into Chinese, French, German, Italian, Japanese, Portuguese and Spanish by fluent English and native speaker translators. Videos of the perioperative period of 30 cats submitted to ovariohysterectomy (preoperative, after surgery, after rescue analgesia and 24 h after surgery) were randomly evaluated twice (one-month interval) by one evaluator for each language unaware of the pain condition. After watching each video, the evaluators scored the unidimensional, UFEPS-SF and Glasgow composite multidimensional feline pain scales. Statistical analyses were carried out using R software for intra and interobserver reliability, principal component analysis, criteria concurrent and predictive validities, construct validity, item-total correlation, internal consistency, specificity, sensitivity, the definition of the intervention score for rescue analgesia and diagnostic uncertainty zone, according to the receiver operating characteristic (ROC) curve.

Results

UFEPS-SF intra- and inter-observer reliability were ≥0.92 and 0.84, respectively, for all observers. According to the principal component analysis, UFEPS-SF is a unidimensional scale. Concurrent criterion validity was confirmed by the high correlation between UFEPS-SF and all other scales (≥0.9). The total score and all items of UFEPS-SF increased after surgery (pain), decreased to baseline after analgesia and were intermediate at 24 h after surgery (moderate pain), confirming responsiveness and construct validity. Item total correlation of each item (0.68-0.83) confirmed that the items contributed homogeneously to the total score. Internal consistency was excellent (≥0.9) for all items. Both specificity (baseline) and sensitivity (after surgery) based on the Youden index was 99% (97-100%). The suggestive cut-off score for the administration of analgesia according to the ROC curve was ≥4 out of 12. The diagnostic uncertainty zone ranged from 3 to 4. The area under the curve of 0.99 indicated excellent discriminatory capacity of UFEPS-SF.

Conclusions

The UFEPS-SF and its items, assessed by experienced evaluators, demonstrated very good repeatability and reproducibility, content, criterion and construct validities, item-total correlation, internal consistency, excellent sensitivity and specificity and a cut-off point indicating the need for rescue analgesia in Chinese, French, English, German, Italian, Japanese, Portuguese and Spanish.

A Pilot Study of Cancer-Induced Bone Pain Using Validated Owner Questionnaires, Serum N-Telopeptide Concentration, Kinetic Analysis, and PET/CT

Cancer-induced bone pain, despite its frequency and severity, is a poorly understood phenomenon in people and animals. Despite excitement regarding translational osteosarcoma studies, there is a lack of attention toward examining cancer pain in dogs. In this pilot study, we used a multimodal pain assessment methodology to evaluate pain relief after therapeutic intervention in dogs with primary bone cancer. We hypothesized that intervention would cause objective evidence of pain relief. Evaluations of 8 dogs with primary bone cancer included ¹⁸F-FDG PET/CT scans, kinetic analysis, validated owner questionnaires (Canine Brief Pain Inventory, canine BPI), and serum N-telopeptide (NTx) concentration. Dogs were routinely staged and had ¹⁸F-FDG PET/CT scans prior to treatment with day 0, 7, 14, and 28 canine BPI, serum NTx, orthopedic exam, and kinetic analysis. Dogs treated with zoledronate and radiation underwent day 28 ¹⁸F-FDG PET scans. All clinical trial work was approved by the University of Missouri IACUC. Four dogs underwent amputation (AMP) for their appendicular bone tumors; four received neoadjuvant zoledronate and hypofractionated radiation therapy (ZOL+RT). Canine BPI revealed significant improvements in pain severity and pain interference scores compared to baseline for all dogs. Positive changes in peak vertical force (+16.7%) and vertical impulse (+29.1%) were noted at day 28 in ZOL+RT dogs. Dogs receiving ZOL+RT had a significant (at least 30%) reduction in serum NTx from baseline compared to amputated dogs (p = 0.029). SUV_max (p = 0.11) and intensity (p = 0.013) values from PET scans decreased while tumor uniformity (p = 0.017) significantly increased in ZOL+RT-treated tumors; gross tumor volume did not change (p = 0.78). Owner questionnaires, kinetic analysis, and ¹⁸F-FDG PET/CT scans showed improved pain relief in dogs receiving ZOL+RT. Serum NTx levels likely do not directly measure pain, but rather the degree of systemic osteoclastic activity. Larger, prospective studies are warranted to identify the ideal objective indicator of pain relief; however, use of multiple assessors is presumably best. With improved assessment of pain severity and relief in dogs with cancer, we can better evaluate the efficacy of our interventions. This could directly benefit people with cancer pain, potentially decreasing the amount of subtherapeutic novel drugs entering human clinical trials.

2022 ISFM Consensus Guidelines on the Management of Acute Pain in Cats

PRACTICAL RELEVANCE

Increases in cat ownership worldwide mean more cats are requiring veterinary care. Illness, trauma and surgery can result in acute pain, and effective management of pain is required for optimal feline welfare (ie, physical health and mental wellbeing). Validated pain assessment tools are available and pain management plans for the individual patient should incorporate pharmacological and non-pharmacological therapy. Preventive and multimodal analgesia, including local anaesthesia, are important principles of pain management, and the choice of analgesic drugs should take into account the type, severity and duration of pain, presence of comorbidities and avoidance of adverse effects. Nursing care, environmental modifications and cat friendly handling are likewise pivotal to the pain management plan, as is a team approach, involving the cat carer.

CLINICAL CHALLENGES

Pain has traditionally been under-recognised in cats. Pain assessment tools are not widely implemented, and signs of pain in this species may be subtle. The unique challenges of feline metabolism and comorbidities may lead to undertreatment of pain and the development of peripheral and central sensitisation. Lack of availability or experience with various analgesic drugs may compromise effective pain management.

EVIDENCE BASE

These Guidelines have been created by a panel of experts and the International Society of Feline Medicine (ISFM) based on the available literature and the authors' experience. They are aimed at general practitioners to assist in the assessment, prevention and management of acute pain in feline patients, and to provide a practical guide to selection and dosing of effective analgesic agents.

Comparative Multimodal Palliative efficacy of gabapentin and tramadol By Using Two Pain Scoring Systems in Cats Undergoing Ovariohysterectomy

The analgesic efficacy of the gabapentin-tramadol combination was compared with meloxicam-tramadol and tramadol perioperative analgesic regimens in cats brought to the clinic for ovariohysterectomy. Thirty adult cats belonging to comparable demographics (age, body weight), were enrolled into a randomized, blinded study after due consent from their owners into four treatment groups. A Gabapentin-Tramadol group (GT-group, n = 10), Meloxicam-Tramadol group (MT-group, n = 10), and a Tramadol group (T-group, n = 10) were formed. Gabapentin capsules at 50 mg were administered orally 2 hours before surgery while the rest received a placebo dose. Tramadol (2 mg/kg, IM) and meloxicam at (0.2 mg/kg, SC) were injected immediately prior to anesthetic premedication. Anesthetic protocol involved premedication with ketamine and xylazine, while anesthesia was induced using propofol. Inhalant isoflurane anesthesia was used to maintain a surgical plane. GT group scored lower on IVAS as well as CPS than MT group, and T group for up to 8 hours after surgery. The mechanical nociceptive threshold remained higher (98±0) for up to 12 hours postoperatively a nd serum cortisol concentrations remained significantly lower during the 24hr period. The addition of gabapentin to the tramadol regimen significantly improved analgesia and mechanical nociceptive threshold than when used on its own.

Current Advances in Assessment of Dog's Emotions, Facial Expressions, and Their Use for Clinical Recognition of Pain

Animals' facial expressions are involuntary responses that serve to communicate the emotions that individuals feel. Due to their close co-existence with humans, broad attention has been given to identifying these expressions in certain species, especially dogs. This review aims to analyze and discuss the advances in identifying the facial expressions of domestic dogs and their clinical utility in recognizing pain as a method to improve daily practice and, in an accessible and effective way, assess the health outcome of dogs. This study focuses on aspects related to the anatomy and physiology of facial expressions in dogs, their emotions, and evaluations of their eyebrows, eyes, lips, and ear positions as changes that reflect pain or nociception. In this regard, research has found that dogs have anatomical configurations that allow them to generate changes in their expressions that similar canids-wolves, for example-cannot produce. Additionally, dogs can perceive emotions similar to those of their human tutors due to close human-animal interaction. This phenomenon-called "emotional contagion"-is triggered precisely by the dog's capacity to identify their owners' gestures and then react by emitting responses with either similar or opposed expressions that correspond to positive or negative stimuli, respectively. In conclusion, facial expressions are essential to maintaining social interaction between dogs and other species, as in their bond with humans. Moreover, this provides valuable information on emotions and the perception of pain, so in dogs, they can serve as valuable elements for recognizing and evaluating pain in clinical settings.

Investigating the effect of anxiety on pain scores in dogs

OBJECTIVE

To investigate the relationship between anxiety and pain scores using the Glasgow Composite Measure Pain Scale-Short Form (CMPS-SF) in dogs.

STUDY

Prospective observational study.

ANIMALS

A group of 18 dogs undergoing surgical management of stifle disease.

METHODS

Preoperatively 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.

RESULTS

When 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 RELEVANCE

No 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.

Behavioral phenotyping of cancer pain in domesticated cats with naturally occurring squamous cell carcinoma of the tongue: initial validation studies provide evidence for regional and widespread algoplasticity

Feline oral squamous cell carcinoma (FOSCC) is a common and naturally occurring condition that recapitulates many features of human head and neck cancer (HNC). In both species, there is need for improved strategies to reduce pain caused by HNC and its treatment. Research to benefit both species could be conducted using pet cats as a comparative model, but this prospect is limited by lack of validated methods for quantifying FOSCC-associated pain. A prospective non-randomized pilot study was performed for initial validation of: (1) a pet owner administered quality of life questionnaire and visual assessment scoring tool (FORQ/CLIENT); (2) a clinician assessment questionnaire (UFEPS/VET); (3) electronic von Frey testing [EVF]; and (4) Cochet-Bonnet (COBO) aesthesiometry. To assess intra-rater reliability, discriminatory ability, and responsiveness of each assay, 6 cats with sublingual SCC and 16 healthy control cats were enrolled. The intra-rater reliability was moderate-to-good for the clinical metrology instruments and EVF (intraclass correlation coefficient [ICC] ≥ 0.68), but poor for COBO (ICC = 0.21). FORQ/CLIENT scores were higher (worse quality of life) in FOSCC cats vs healthy controls. The internal reliability of FORQ/CLIENT scoring was high (Cronbach α = 0.92); sensitivity and specificity were excellent (100% when using cut-offs determined using receiver operating characteristic [ROC] curves). For the FORQ/CLIENT, there was strong and inverse correlation between scores from the questions and visual assessment (r =  − 0.77, r² = 0.6, P < 0.0001). For the UFEPS/VET, Cronbach’s α was 0.74 (high reliability). Sensitivity and specificity were 100% and 94%, respectively, when using a cut-off score (3.5) based on ROC curves (Youden index of 0.94). Total UFEPS/VET scores were positively correlated with FORQ/CLIENT scores (r² = 0.72, P < 0.0001). Sensitivity of EVF and COBO ranged from 83 to 100% and specificity ranged from 56 to 94%. Cats with cancer were more sensitive around the face (lower response thresholds) and on the cornea (longer filament lengths) than control animals (P < 0.03). Reduced pressure response thresholds were also observed at a distant site (P = 0.0002) in cancer cats. After giving buprenorphine, EVF pressure response thresholds increased (P = 0.04) near the mandible of cats with OSCC; the length of filament required to elicit a response in the COBO assay also improved (shortened; P = 0.017). Based on these preliminary assessments, the assays described herein had reasonable inter-rater reliability, and they were able to both discriminate between cats with and without oral cancer, and respond in a predictable manner to analgesic therapy. In cats with tongue cancer, there was evidence for regional peripheral sensitization, and widespread somatosensory sensitization. These results provide a basis for multi-dimensional assessments of pain and sensitivity in cats with oral SCC.

A critical evaluation for validation of composite and unidimensional postoperative pain scales in horses

Proper pain therapy requires adequate pain assessment. This study evaluated the reliability and validity of the Unesp-Botucatu horse acute pain scale (UHAPS), the Orthopedic Composite Pain Scale (CPS) and unidimensional scales in horses admitted for orthopedic and soft tissue surgery. Forty-two horses were assessed and videotaped before surgery, up to 4 hours postoperatively, up to 3 hours after analgesic treatment, and 24 hours postoperatively (168 video clips). After six evaluators viewing each edited video clip twice in random order at a 20-day interval, they chose whether analgesia would be indicated and applied the Simple Descriptive, Numeric and Visual Analog scales, CPS, and UHAPS. For all evaluators, intra-observer reliability of UHAPS and CPS ranged from 0.70 to 0.97. Reproducibility was variable among the evaluators and ranged from poor to very good for all scales. Principal component analysis showed a weak association among 50% and 62% of the UHAPS and CPS items, respectively. Criterion validity based on Spearman correlation among all scales was above 0.67. Internal consistency was minimally acceptable (0.51–0.64). Item-total correlation was acceptable (0.3–0.7) for 50% and 38% of UHAPS and CPS items, respectively. UHAPS and CPS were specific (90% and 79% respectively), but both were not sensitive (43 and 38%, respectively). Construct validity (responsiveness) was confirmed for all scales because pain scores increased after surgery. The cut-off point for rescue analgesia was ≥ 5 and ≥ 7 for the UHAPS and CPS, respectively. All scales presented adequate repeatability, criterion validity, and partial responsiveness. Both composite scales showed poor association among items, minimally acceptable internal consistency, and weak sensitivity, indicating that they are suboptimal instruments for assessing postoperative pain. Both composite scales require further refinement with the exclusion of redundant or needless items and reduction of their maximum score applied to each item or should be replaced by other tools.

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

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

Angularis oris axial pattern flap as a reliable and versatile option for rostral facial reconstruction in cats

OBJECTIVE

To evaluate outcomes associated with the use of an angularis oris axial pattern flap (AOAPF) for rostral facial reconstruction in cats.

ANIMALS

Nine adult client-owned cats.

STUDY DESIGN

Short case series.

METHODS

Ten AOAPF were performed in nine cats after resection of a tumor. Wounds were located at the nose, infraorbital, supraorbital, frontal, eye, and ear canal region. Orbital exenteration (n = 3), pinnectomy (n = 2), nasal planum resection, total ear canal ablation (n = 2), and partial eyelid reconstruction (n = 3) were performed.

RESULTS

Short-term postoperative complications included flap edema (n = 10), suture dehiscence (n = 3), and distal tip necrosis (n = 3). All wounds resulting from minor complications healed by second intention in 5-15 days. Long-term complications included epiphora (n = 2), frequent grooming around the eyes (n = 2), and enucleation due to corneal ulcer secondary to impaired postoperative eyelid function (n = 1). Tumor recurrence occurred in 3 cases.

CONCLUSION

The AOAPF was a versatile and reliable option for rostral facial reconstruction in cats with acceptable long-term outcomes.

Validation of the Donkey Pain Scale (DOPS) for Assessing Postoperative Pain in Donkeys

This study aimed to validate a scale for assessing acute pain in donkeys. Forty-four adult donkeys underwent castration after sedation with intravenous (IV) xylazine, induction with guaifenesin and thiopental IV, local anesthetic block, and maintenance with isoflurane. The scale was constructed from a pilot study with four animals combined with algetic behaviors described for equines. After content validation, the scale was evaluated in 40 other donkeys by three blinded and one reference evaluator, by means of edited videos referring to the preoperative and postoperative periods: before anesthesia, 3-4 h after recovery from anesthesia, 5-6 h after recovery from anesthesia (2 h after analgesia with flunixin-1.1 mg/kg, dipyrone-10 mg/kg, and morphine-0.2 mg/kg) IV, and 24 h after recovery. Content validity, sensitivity, specificity, and responsiveness of behaviors were investigated to refine the scale. Intra- and inter-evaluator reliabilities were investigated by the weighted kappa coefficient, criterion validity by comparing the scale with the visual analog scale (VAS), internal consistency by Cronbach's α coefficient, item-total correlation by the Spearman coefficient, and intervention point for rescue analgesic by the receiver operating characteristics curve and Youden index. The scale showed very good intra-evaluator reliability (0.88-0.96), good to moderate (0.56-0.66) inter-evaluator reliability, responsiveness for all items, good criterion validity vs. VAS (0.75), acceptable internal consistency (0.64), adequate item-total correlation, except for head position and direction, and according to the principal component analysis, good association among items. The accuracy of the point for rescue analgesic was excellent (area under the curve = 0.91). The rescue analgesic score was ≥ 4 of 11 points. The scale can diagnose and quantify acute pain in donkeys submitted to castration, as the instrument is reliable and valid, with a defined intervention analgesic score.

A pilot study of transdermal gabapentin in cats

Background

Clinical use of gabapentin has increased; transdermal delivery in cats is incompletely studied.

Objective

To evaluate if gabapentin permeates feline skin in vitro and in vivo and to determine if pain scores improve after administration.

Animals

In vitro: cadaver skin from 6 cats; phase 1: 8 young, healthy client‐owned cats; phase 2: 15 client‐owned geriatric cats.

Methods

In vitro, gabapentin applied every q12h to ear or cervical skin in diffusion cells. Samples collected at 0, 2, 4, 12, and 24 hours after application. Phase 1: Cats assigned to 1 of 4 groups: 5 mg/kg or 10 mg/kg applied q8h for 5 days to either ear or cervical skin. Serum samples collected predose, and after 1 and 5 days. Phase 2: 10 mg/kg applied q8h for 5 days. Two validated pain scores recorded predose, and after days 1, 5, and 8. Serum samples collected predose, and after days 1 and 5. Samples were frozen at −80°C for concentration analysis utilizing a validated high‐performance liquid chromatography mass‐spectrometry method.

Results

Gabapentin was identified in all samples. Significant differences in gabapentin concentrations were observed from day 1 to day 5 (P < .02) and in pain scores from predose to day 5 (P < .05) and day 1 to day 5 (P < .05). No differences in pain scores were observed from predose to day 8 (P = .3).

Conclusions and Clinical Relevance

Gabapentin in a transdermal base penetrates feline skin in vitro, is absorbed systemically in cats, and may help decrease pain scores.

Development and validation of the facial scale (FaceSed) to evaluate sedation in horses

Although facial characteristics are used to estimate horse sedation, there are no studies measuring their reliability and validity. This randomised controlled, prospective, horizontal study aimed to validate a facial sedation scale for horses (FaceSed). Seven horses received detomidine infusion i.v. in low or high doses/rates alone (DL 2.5 μg/kg+6.25 μg/kg/h; DH 5 μg/kg+12.5 μg/kg/h) or combined with methadone (DLM and DHM, 0.2 mg/kg+0.05 mg/kg/h) for 120 min, or acepromazine boli i.v. in low (ACPL 0.02 mg/kg) or high doses (ACPH 0.09 mg/kg). Horses' faces were photographed at i) baseline, ii) peak, iii) intermediate, and iv) end of sedation. After randomisation of moments and treatments, photos were sent to four evaluators to assess the FaceSed items (ear position, orbital opening, relaxation of the lower and upper lip) twice, within a one-month interval. The intraclass correlation coefficient of intra- and interobserver reliability of FaceSed scores were good to very good (0.74-0.94) and moderate to very good (0.57-0.87), respectively. Criterion validity based on Spearman correlation between the FaceSed versus the numerical rating scale and head height above the ground were 0.92 and -0.75, respectively. All items and the FaceSed total score showed responsiveness (construct validity). According to the principal component analysis all FaceSed items had load factors >0.50 at the first dimension. The high internal consistency (Cronbach´s α = 0.83) indicated good intercorrelation among items. Item-total Spearman correlation was adequate (rho 0.3-0.73), indicating homogeneity of the scale. All items showed sensitivity (0.82-0.97) to detect sedation, however only orbital opening (0.79) and upper lip relaxation (0.82) were specific to detect absence of sedation. The limitations were that the facial expression was performed using photos, which do not represent the facial movement and the horses were docile, which may have reduced specificity. The FaceSed is a valid and reliable tool to assess tranquilisation and sedation in horses.

Spontaneous Behaviors of Post-Orchiectomy Pain in Horses Regardless of the Effects of Time of Day, Anesthesia, and Analgesia

This prospective and longitudinal study aimed to identify spontaneous post-orchiectomy pain behaviors in horses regardless of the effects of anesthesia, analgesia, and recording time of day. Twenty-four horses divided into four groups were submitted to: inhalation anesthesia only (GA), or combined with previous analgesia (GAA), or orchiectomy under pre (GCA), or postoperative (GC) analgesia. The data obtained from the subtraction of frequency and/or duration of 34 behaviors recorded during seven 60-min time-points in the 24 h after the anesthesia from those recorded in the mirrored time-points in the 24 h before the anesthesia (delta) were compared over time and among groups by Friedman and Kruskal-Wallis tests, respectively (p < 0.05). Time of day influenced the behaviors of walk, look out the window, rest the pelvic limb, and rest standing still. The only pain-related behaviors were decreased mirrored proportional differences in time spent drinking, and eating, and increased mirrored proportional differences in the frequency or duration of look at the wound, retract the pelvic limb, expose the penis, and look at the back of the stall. In conclusion, confounding factors rather than pain may influence several suggestive pain-related behaviors documented in the literature.

Clinical validation of the short and long UNESP-Botucatu scales for feline pain assessment

Background

The UNESP-Botucatu multidimensional feline pain assessment scale (UFEPS) is a valid and reliable instrument for acute pain assessment in cats. However, its limitations are that responsiveness was not tested using a negative control group, it was validated only for ovariohysterectomy, and it can be time-consuming. We aimed to evaluate the construct and criterion validity, reliability, sensitivity, and specificity of the UFEPS and its novel short form (SF) in various clinical or painful surgical conditions.

Methods

Ten client-owned healthy controls (CG) and 40 client-owned cats requiring pain management for clinical or surgical care (20 clinical and 20 surgery group (12 orthopedic and eight soft tissue surgeries) were recruited. Three evaluators assessed pain, in real-time, in clinical cases before and 20 min after rescue analgesia and in surgical cases before and up to 6.5 hours postoperatively, by using the visual analog, numerical ratio, and a simple descriptive scale, in this order, followed by the UFEPS-SF, UFEPS and Glasgow multidimensional feline pain (Glasgow CMPS-Feline) in random order. For the surgical group, rescue analgesia (methadone 0.2 mg/kg IM or IV and/or dipyrone 12.5 mg/kg IV) was performed when the UFEPS-SF score was ≥4 or exceptionally according to clinical judgement. If a third interventional analgesia was required, methadone (0.1-0.2 mg/kg IM) and ketamine (1 mg/kg IM) were administered. For the clinical group, all cats received rescue analgesia (methadone 0.1-0.2 mg/kg IM or IV or nalbuphine 0.5 mg/kg IM or IV), according to the clinician in charge, regardless of pain scores. Construct (1-comparison of scores in cats undergoing pain vs pain-free control cats by unpaired Wilcoxon-test and 2-responsiveness to analgesia by paired Wilcoxon test) and concurrent criterion validity (Spearman correlation of the total score among scales), inter-rater reliability, specificity and sensitivity were calculated for each scale (α = 0.05).

Results

Reliability ranged between moderate and good for the UFEPS and UFEPS-SF (confidence intervals of intraclass coefficients = 0.73-0.86 and 0.63-0.82 respectively). The Spearman correlation between UFEPS and UFEPS-SF was 0.85, and their correlation with Glasgow CMPS-Feline was strong (0.79 and 0.78 respectively), confirming criterion validity. All scales showed construct validity or responsiveness (higher scores of cats with clinical and postoperative pain vs healthy controls, and the reduction in scores after rescue analgesia). The sensitivity and specificity of the UFEPS, UFEPS-SF and Glasgow CMPS-Feline were moderate (sensitivity 83.25, 78.60% and 74.28%; specificity 72.00, 84.67 and 70.00%, respectively).

Conclusions

Both UFEPS and UFEPS-SF showed appropriate concurrent validity, responsiveness, reliability, sensitivity, and specificity for feline acute pain assessment in cats with various clinical and orthopedic and soft tissue surgical conditions.

Measurement of ground reaction forces in cats 1 year after femoral head and neck ostectomy

OBJECTIVES

The objective of this study was to compare ground reaction forces (GRFs) of a group of cats after femoral head and neck ostectomy (FHO) with those of a historical control group.

METHODS

We searched the database of the Small Animal Clinic of the Veterinary University in Vienna for cats that had undergone unilateral FHO at least 1 year previously. Owners were telephoned and invited to the clinic with their cats for a re-examination. An in-house owner questionnaire-based evaluation, complete orthopaedic examination, hip radiography and gait analysis with a pressure-sensitive plate were performed, and results were compared within and between groups (FHO group and control group [CG]).

RESULTS

Seventeen cats that had undergone FHO (FHO group) at least 1 year previously and 15 healthy cats (CG) from a previous study were included. Measured GRFs (peak vertical force and vertical impulse [IFz] normalised to total force [%TF]) of the FHO legs were lower than those of the other legs of the FHO group and the legs of the CG. Results of the owner questionnaire were generally good and did not match the results of the GRF comparison. Furthermore, the gaits evaluated during the orthopaedic examination did not correlate with the measured GRFs where we identified a certain degree of lameness (reduced IFz, %TF) in all cats. Cats with limb shortening (dorsally displaced major trochanter major) were not revealed to have different GRF measurements.

CONCLUSIONS AND RELEVANCE

This is the first study to assess GRFs in a large group of cats that had undergone FHO, comparing findings with those in healthy cats. Even if the differences are statistically significant, but rather small, our findings point to a long-term residual gait abnormality that could be detected using a pressure-sensitive plate but not always with an orthopaedic examination, in cats 1 year after FHO.

Use of Spinal Anaesthesia with Anaesthetic Block of Intercostal Nerves Compared to a Continuous Infusion of Sufentanyl to Improve Analgesia in Cats Undergoing Unilateral Mastectomy

Simple Summary

Postoperative analgesia is very important because pain causes various negative effects that prevent patient recovery. Our study aimed to evaluate the analgesic efficacy of subarachnoid anaesthesia combined with intercostal nerve block compared with a constant-rate infusion of sufentanyl citrate in cats undergoing unilateral mastectomy. This study demonstrated that the use of spinal anaesthesia with anaesthetic block of intercostal nerves, using levobupivacaine, guarantees long-lasting and high-quality analgesic coverage and minimises the post-surgical pain inevitably associated with invasive surgical procedures such as radical mastectomy. This study stemmed from a general trend towards increasing attention on postoperative pain after spaying procedures in cats. Since veterinarians are becoming more focused on relieving surgical pain, anaesthetists are expected to use better protocols that can minimise pain and therefore optimise surgical results. This method, considering the relative simplicity of its execution, can be used in daily clinical practice.

Abstract

Unilateral mastectomy is a common surgical procedure in feline species and requires postoperative pain management. Our study aimed to evaluate the analgesic efficacy of subarachnoid anaesthesia combined with an intercostal nerve block, in comparison with the use of sufentanyl citrate administered as a constant-rate infusion (CRI). Twenty cats were randomly divided into two groups (n = 10/group) based on the analgesic protocol used: the first received loco-regional anaesthesia with levobupivacaine (LR group), and the second received a CRI of sufentanyl (SUF group). The evaluation criteria during surgery were the need for a bolus of fentanyl in the event of an increased heart rate or increased blood pressure. In the postoperative period, the levels of comfort/discomfort and pain were used to obtain a score according to the UNESP-Botucatu multimodal scale. Subjects who scored above seven received analgesic drug supplementation. Intraoperative analgesia was satisfactory, with good haemodynamic stability in both groups. Four patients in the LR group required an extra dose of methadone after they achieved the sternal decubitus position, whereas those in the SUF group required many more doses. The analgesia achieved in the LR group was more satisfactory than that in the SUF group.

Development, Validation, and Reliability of a Sedation Scale in Horses (EquiSed)

The lack of standardization of sedation scales in horses limits the reproducibility between different studies. This prospective, randomized, blinded, horizontal and controlled trial aimed to validate a scale for sedation in horses (EquiSed). Seven horses were treated with intravenous detomidine in low/high doses alone (DL 2.5 μg/kg + 6.25 μg/kg/h; DH 5 μg/kg +12.5 μg/kg/h) or associated with methadone (DLM and DHM, 0.2 mg/kg + 0.05 mg/kg/h) and with low (ACPL 0.02 mg/kg) or high (ACPH 0.09 mg/kg) doses of acepromazine alone. Horses were filmed at (i) baseline (ii) peak, (iii) intermediate, and (iv) end of sedation immediately before auditory, visual and pressure stimuli were applied and postural instability evaluated for another study. Videos were randomized and blindly evaluated by four evaluators in two phases with 1-month interval. Intra- and interobserver reliability of the sum of EquiSed (Intraclass correlation coefficient) ranged between 0.84-0.94 and 0.45-0.88, respectively. The criterion validity was endorsed by the high Spearman correlation between the EquiSed and visual analog (0.77), numerical rating (0.76), and simple descriptive scales (0.70), and average correlation with head height above the ground (HHAG) (-0.52). The Friedman test confirmed the EquiSed responsiveness over time. The principal component analysis showed that all items of the scale had a load factor ≥ 0.50. The item-total Spearman correlation for all items ranged from 0.3 to 0.5, and the internal consistency was good (Cronbach's α = 0.73). The area under the curve of EquiSed HHAG as a predictive diagnostic measure was 0.88. The sensitivity of the EquiSed calculated according to the cut-off point (score 7 of the sum of the EquiSed) determined by the receiver operating characteristic curve, was 96% and specificity was 83%. EquiSed has good intra- and interobserver reliabilities and is valid to evaluate tranquilization and sedation in horses.

ACVIM consensus statement on pancreatitis in cats

Background

Pancreatitis in cats, although commonly diagnosed, still presents many diagnostic and management challenges.

Objective

To summarize the current literature as it relates to etiology, pathogenesis, diagnosis, and management of pancreatitis in cats and to arrive at clinically relevant suggestions for veterinary clinicians that are based on evidence, and where such evidence is lacking, based on consensus of experts in the field.

Animals

None.

Methods

A panel of 8 experts in the field (5 internists, 1 radiologist, 1 clinical pathologist, and 1 anatomic pathologist), with support from a librarian, was formed to assess and summarize evidence in the peer reviewed literature and complement it with consensus clinical recommendations.

Results

There was little literature on the etiology and pathogenesis of spontaneous pancreatitis in cats, but there was much in the literature about the disease in humans, along with some experimental evidence in cats and nonfeline species. Most evidence was in the area of diagnosis of pancreatitis in cats, which was summarized carefully. In contrast, there was little evidence on the management of pancreatitis in cats.

Conclusions and Clinical Importance

Pancreatitis is amenable to antemortem diagnosis by integrating all clinical and diagnostic information available, and recognizing that acute pancreatitis is far easier to diagnose than chronic pancreatitis. Although both forms of pancreatitis can be managed successfully in many cats, management measures are far less clearly defined for chronic pancreatitis.

The Application of Geometric Morphometrics to Explore Potential Impacts of Anthropocentric Selection on Animals' Ability to Communicate via the Face: The Domestic Cat as a Case Study

During their domestication via artificial selection, humans have substantially modified the morphology and thus visual appearance of non-human animals. While research highlights the negative impact of these modifications on physical functioning, little is known about their impact on behavior and signaling, either toward humans or conspecifics. Changes in the appearance of the face, such as those associated with, but not limited to, facial expressions, form an important part of non-verbal communication. In companion animals, the face is one of their most visually diverse features (due to human-driven selection), which may impact the visual clarity of expressions and other forms of signaling. Using the domestic cat as our model, we applied a new analytical technique in order to understand the impact of breed variation on relative positioning of facial landmarks, chosen specifically for their association with the production of various facial movements, and the expression of affect. We then assessed the extent to which facial appearances known to be associated with a specific underlying state (i.e., pain, assessed via a validated, facial pain score), could be reliably detected in a morphologically diverse population. Substantial baseline variation in landmarks was identified at both the cephalic (e.g., brachycephalic, dolichocephalic, mesocephalic) as well as breed levels. While differences in facial pain scores could successfully differentiate between "pain" and "no pain" in the facial appearance of domestic shorthaired cats (DSH), these differences were no longer detectable when assessed within a larger more morphologically diverse population, after corrections for multiple testing were applied. There was also considerable overlap between pain scores in the DSH "pain" population and the neutral faces of other breeds. Additionally, for several paedomorphic breeds, their neutral face shapes produced scores indicative of greater pain, compared to most other breeds, including the DSH cats actually in pain. Our findings highlight the degree to which anthropocentric selection might disrupt the communicative content of animals' faces, in this case the domestic cat. These results also suggest a potential human preference for features extending beyond the infantile, to include negatively-valenced facial forms such as pain.

Postoperative pain behaviours in rabbits following orthopaedic surgery and effect of observer presence

Rabbits are widely used in studies focusing on pain. However, pain is undertreated in this species and one possible factor to explain this is the lack of evaluation methods. The objective of this study was to identify behaviours related to orthopaedic pain in rabbits and to evaluate the influence of the presence of an observer on these behaviours. Twenty-eight rabbits undergoing orthopaedic surgery and filmed 24 hours before surgery, and 1 hour (before rescue analgesia), 4 hours (3 hours after rescue analgesia), and 24 hours post-recovery were observed in the presence and absence of an observer. The frequency and/or duration of behaviours were compared over time and between the presence and absence of the observer using the Friedman and Wilcoxon tests respectively. Data are expressed as median and interquartile range and a significant difference was considered when p<0.05. At 1 hour post-recovery, the rabbits showed reduced activity, hopping, change posture, position in the cage, explore, and open eyes in both the presence and absence of the observer. In the absence of the observer, quadrupedal posture, interact with pinecone, and eat carrot also decreased, while wince behaviour increased. In the presence of the observer, before surgery, the rabbits were less active (Presence-280; 162-300, Absence-300; 300-300) and presented a lower duration of explore (Presence-3; 0-32, Absence-40; 4-63). Post-recovery the rabbits flinched less (Presence-0; 0-0, Absence-0; 0-1) and suspended the affected limb less (Presence-0; 0-0, Absence-0; 0-65). After rescue analgesia the rabbits put weight on and raised the affected limb less (Presence-0; 0-0, Absence-0; 0-2) and licked the affected area less (Presence-0; 0-0, Absence-0; 0-2). These findings demonstrate that the presence of the observer inhibited pain-free behaviours in the rabbits, leading to a false impression of pain, and after the surgery the rabbits masked some pain signs related to the affected area.

Validation of the Unesp-Botucatu composite scale to assess acute postoperative abdominal pain in sheep (USAPS)

A scale with robust statistical validation is essential to diagnose pain and improve decision making for analgesia. This blind, randomised, prospective and opportunist study aimed to develop an ethogram to evaluate behaviour and validate a scale to assess acute ovine postoperative pain. Elective laparoscopy was performed in 48 healthy sheep, filmed at one preoperative and three postoperative moments, before and after rescue analgesia and 24 hours after. The videos were randomised and assessed twice by four evaluators, with a one-month interval between evaluations. Statistical analysis was performed using R software and differences were considered significant when p <0.05. Based on the multiple association, a unidimensional scale was adopted. The intra- and inter-observer reliability ranged from moderate to very good (intraclass correlation coefficient ≥ 0.53). The scale presented Spearman correlations > 0.80 with the numerical, simple descriptive, and visual analogue scales, and a correlation of 0.48 with the facial expression scale. According to the mixed linear model, the scale was responsive, due to the increase and decrease in pain scores of all items after surgery and analgesic intervention, respectively. All items on the scale demonstrated an acceptable Spearman item-total correlation (0.56-0.76), except for appetite (0.25). The internal consistency was excellent (Cronbach's α = 0.81) and all items presented specificity > 0.72 and sensitivity between 0.61-0.90, except for appetite. According to the Youden index, the cut-off point was ≥ 4 out of 12, with a diagnostic uncertainty zone of 4 to 5. The area under the curve > 0.95 demonstrated the excellent discriminatory capacity of the instrument. In conclusion, the Unesp-Botucatu pain scale in sheep submitted to laparoscopy is valid, reliable, specific, sensitive, with excellent internal consistency, accuracy, discriminatory capacity, and a defined cut-off point.

Evaluation of tumescent local anesthesia in cats undergoing unilateral mastectomy

OBJECTIVE

To evaluate the analgesic efficacy and safety of tumescent local anesthesia (TLA) in cats undergoing unilateral mastectomy.

STUDY DESIGN

Prospective clinical trial.

ANIMALS

A total of 12 ovariohysterectomized female cats.

METHODS

All animals were premedicated with pethidine (4 mg kg^-1) intramuscularly (IM), followed by induction of anesthesia with propofol (5 mg kg^-1) intravenously and maintenance with isoflurane in oxygen. A refrigerated TLA solution (15 mL kg^-1, 8 °C) was injected using a Klein cannula. The solution was composed of 0.5 mL of epinephrine (1 mg mL^-1) and 40 mL of 2% lidocaine added to 210 mL lactated Ringer's solution (final lidocaine concentration 0.32%). Heart and respiratory rates, systolic arterial blood pressure, temperature and oxygen saturation were measured during anesthesia. Blood samples were collected from the jugular vein for measurement of plasma lidocaine concentration using high performance liquid chromatography. Postoperative pain scores were evaluated hourly for 6 hours. Analgesic rescue was performed with tramadol (2 mg kg^-1) IM and meloxicam (0.15 mg kg^-1) subcutaneously.

RESULTS

Plasma lidocaine concentration peaked at 90 minutes after injection of TLA, but no concentration considered toxic for the species was measured. The median postoperative analgesia time was 6 hours after injection of TLA.

CONCLUSIONS

This study found that TLA prevented sympathetic response to noxious stimuli during anesthesia and provided satisfactory postoperative analgesia in cats submitted to total unilateral mastectomy, with no apparent signs of toxicity.

CLINICAL RELEVANCE

TLA can prevent sympathetic stimulation resulting from noxious stimuli during anesthesia, promoting good intraoperative conditions, proving to be a viable addition to analgesia in cats submitted to a total unilateral mastectomy.

Methods of Assessment of the Welfare of Shelter Cats: A Review

At any moment, there are millions of cats housed in foster care facilities for abandoned and stray animals for various reasons worldwide. Care, management and regulation among these facilities differ. Moreover, shelters can never substitute the full comfort of a good home for the animal, and the welfare of cats in shelters is a subject of discussion in many respects. Cats are animals sensitive to changes; for most of them, placement in a shelter is a stressful experience because of changes in routine, environment and the presence of other animals. Stress is reflected in changes in behaviour, causes fluctuations in physiological values and disrupts the immune system, which is a predisposition to the development or reactivation of disease. Evaluation of the presence and intensity of negative impacts is possible through the use of evaluation tools based on indicators that help set the environment and management of keeping so as to disrupt the quality of life as little as possible. Although a comprehensive and valid welfare tool that would evaluate animal-based and at the same time resource-based (or management-based) indicators of cats in shelters is not currently available, it is possible to use partial evaluation of individual welfare indicators to assess welfare. This review aims to provide the readers with an insight into current options of assessment of the welfare of cats in shelters with an emphasis on behavioural, physiological and health indicators with an application in both practical and scientific contexts.

A randomized clinical trial comparing butorphanol and buprenorphine within a multimodal analgesic protocol in cats undergoing orchiectomy

OBJECTIVES

The aim of this study was to compare the effects of butorphanol and buprenorphine, as part of a multimodal analgesic protocol, on recovery and analgesia in cats undergoing orchiectomy.

METHODS

In a prospective, randomized, blind clinical trial, 47 adult male cats were randomly assigned to receive either butorphanol (0.3 mg/kg, n = 24) or buprenorphine (0.02 mg/kg, n = 23) in combination with dexmedetomidine (25 μg/kg) and alfaxalone (2 mg/kg) as a single intramuscular injection for the induction of general anesthesia. Isoflurane carried in oxygen was supplemented as needed during orchiectomy. All cats received lidocaine (2 mg/kg intratesticular), meloxicam (0.3 mg/kg SC) and atipamezole (125 μg/kg IM) postoperatively. Pain and sedation scales were applied at baseline, and 2, 4 and 6 h postoperatively. Time to achieve sternal recumbency and to begin eating were also recorded.

RESULTS

Pain scale scores were low and showed no difference between the treatment groups at all time points (P ⩾0.99, all time points). Four cats exceeded the analgesia intervention threshold for rescue analgesia (butorphanol, n = 3; buprenorphine, n = 1). There was no difference in sedation scores between groups at any time point (P >0.99, all time points). Significantly more cats in the buprenorphine group (n = 12) required isoflurane than in the butorphanol group (n = 2) (P = 0.0013; relative risk 6.3, 95% confidence interval [CI] 1.8-23.5). There was no significant difference in time to achieve sternal recumbency (P = 0.96, 95% CI -20 to 20) between groups or in return to eating (P = 0.48, 95% CI -92.0 to 113.5), with most cats eating within 1 h of surgery (butorphanol, 79%; buprenorphine, 83%).

CONCLUSIONS AND RELEVANCE

There were no significant differences in analgesia or recovery between butorphanol and buprenorphine treatment groups as part of a multimodal injectable anesthetic protocol. Butorphanol is associated with superior depth of anesthesia, facilitating injectable anesthesia.

The development and use of facial grimace scales for pain measurement in animals

The measurement of pain in animals is surprisingly complex, and remains a critical issue in veterinary care and biomedical research. Based on the known utility of pain measurement via facial expression in verbal and especially non-verbal human populations, "grimace scales" were first developed a decade ago for use in rodents and now exist for 10 different mammalian species. This review details the background context, historical development, features (including duration), psychometric properties, modulatory factors, and impact of animal grimace scales for pain.

Validation of the UNESP-Botucatu pig composite acute pain scale (UPAPS)

The creation of species-specific valid tools for pain assessment is essential to recognize pain and determine the requirement and efficacy of analgesic treatments. This study aimed to assess behaviour and investigate the validity and reliability of an acute pain scale in pigs undergoing orchiectomy. Forty-five pigs aged 38±3 days were castrated under local anaesthesia. Behaviour was video-recorded 30 minutes before and intermittently up to 24 hours after castration. Edited footage (before surgery, after surgery before and after rescue analgesia, and 24 hours postoperatively) was analysed twice (one month apart) by one observer who was present during video-recording (in-person researcher) and three blinded observers. Statistical analysis was performed using R software and differences were considered significant when p<0.05. Intra and inter-observer agreement, based on intra-class correlation coefficient, was good or very good between most observers (>0.60), except between observers 1 and 3 (moderate agreement 0.57). The scale was unidimensional according to principal component analysis. The scale showed acceptable item-total Spearman correlation, excellent predictive and concurrent criterion validity (Spearman correlation ≥ 0.85 between the proposed scale versus visual analogue, numerical rating, and simple descriptive scales), internal consistency (Cronbach's α coefficient >0.80 for all items), responsiveness (the pain scores of all items of the scale increased after castration and decreased after intervention analgesia according to Friedman test), and specificity (> 95%). Sensitivity was good or excellent for most of the items. The optimal cut-off point for rescue analgesia was ≥ 6 of 18. Discriminatory ability was excellent for all observers according to the area under the curve (>0.95). The proposed scale is a reliable and valid instrument and may be used clinically and experimentally to assess postoperative acute pain in pigs. The well-defined cut-off point supports the evaluator´s decision to provide or not analgesia.

Inter-Rater Reliability of the Feline Grimace Scale in Cats Undergoing Dental Extractions

This study aimed to evaluate the inter-rater reliability of the Feline Grimace Scale (FGS) in cats undergoing dental extractions and the effects of the caregiver's presence on the FGS scores. Twenty-four cats (6 ± 3.3 years old; 4.9 ± 1.7 kg) undergoing oral treatment were included in a prospective, blinded, randomized, clinical study. They underwent treatment under general anesthesia (acepromazine-hydromorphone-propofol-isoflurane-meloxicam-local anesthetic blocks) at day 1 and were discharged at day 6. Images of cat faces were captured from video recordings with or without the caregiver's presence at 6 h postoperatively (day 1), day 6, and before and after rescue analgesia. Images were randomized and independently evaluated by four raters using the FGS [five action units (AU): ear position, orbital tightening, muzzle tension, whiskers change, and head position; score 0-2 for each]. Inter-rater reliability and the effects of the caregiver's presence were analyzed with intraclass correlation coefficient [single measures (95% confidence interval)] and the Wilcoxon signed-rank test, respectively (p < 0.05). A total of 91 images were scored. Total FGS scores showed good inter-rater reliability [0.84 (0.77-0.89)]. Reliability for each AU was: ears [0.68 (0.55-0.78)], orbital tightening [0.76 (0.65-0.84)], muzzle [0.56 (0.43-0.69)], whiskers [0.64 (0.50-0.76)], and head position [0.74 (0.63-0.82)]. The FGS scores were not different with [0.075 (0-0.325)] or without [0.088 (0-0.525)] the caregivers' presence (p = 0.12). The FGS is a reliable tool for pain assessment in cats undergoing dental extractions. The caregiver's presence did not affect FGS scores.