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.

Real-time ultrasound-guided lumbosacral epidural anaesthesia in obese or appropriate body condition score dogs: A randomized clinical trial.

Correctly identifying the puncture site and needle position in obese dogs can be challenging to achieve epidural anaesthesia. The current study aimed to evaluate a real-time ultrasound-guided technique, to perform epidural anaesthesia in obese or appropriate body condition score dogs, based on visualization of local anaesthetic flow during its injection, compared to the traditional method of palpation of anatomical landmarks. Seventy-two client-owned dogs were evaluated in a prospective, comparative, randomized clinical trial, allocated into four groups of 18 dogs. For the Palpation-guided 1 (PG1) and 2 (PG2) groups, epidural anaesthesia was based on palpating anatomical landmarks. Dogs with a body condition score (BCS) 1-5/9 were included in the PG1 (non-obese), and those with a BCS 6-9/9 in PG2 (obese) groups. In the Ultrasound-guided 1 (USG1 - BCS 1-5/9) and 2 (USG2 - BCS 6-9/9) groups, epidural anaesthesia was guided by ultrasound (US). The flow of anaesthetic through the epidural canal was observed in all dogs by US. There were fewer needle-to-bone contacts in the US-guided groups when performing epidural anaesthesia; this only occurred on the vertebral laminae, never in the vertebral canal. Ultrasound guidance enabled local anaesthetic injection into the epidural space without the need for palpation of anatomical landmarks to guide needle placement. Blood reflux occurred in 11.1% (PG1), 22.2% (PG2), 5.5% (USG1), and 0% (USG2) of the dogs. Ultrasound-guided punctures led to fewer vascular punctures. Epidural anaesthesia was effective in all animals, and no complications were observed.

Avaliação psicométrica em português do indicador de dor crônica de Helsinki em cães com sinais crônicos de osteoartrite / Psychometric testing in Portuguese of Helsinki's chronic pain index for dogs with chronic signs of osteoarthritis

Objetivou-se determinar a validade, a confiabilidade e a sensibilidade do indicador de dor crônica de Helsinki (IDCH) em português, além de estabelecer correlação entre a plataforma de pressão em cães com displasia coxofemoral (DCF). O questionário foi preenchido por tutores de 40 animais com DCF e por 16 tutores de cães saudáveis. Os animais com DCF foram tratados com carprofeno 4,4mg/kg (GT= 21) ou placebo (GP= 19), administrados uma vez ao dia, durante quatro semanas. A avaliação consistiu no preenchimento do questionário (IDCH), na escala analógica visual de dor (EAVdor) e na escala analógica visual de locomoção (EAVloc) com duas semanas (A1) e imediatamente antes do tratamento (A2), duas (S2) e quatro (S4) semanas de tratamento e após duas semanas do término do tratamento (S6). A consistência interna dos dados foi considerada excelente (alfa de Cronbach = 0,89). Houve correlação moderada entre o IDCH e a EAVdor e boa entre o IDCH e a EAVloc, porém não houve diferença entre o grupo tratado com carprofeno e placebo no IDCH. Não houve correlação entre os dados da plataforma de pressão e o IDCH. O questionário apresentou validade de constructo, critério e fidedignidade e pode-se empregá-lo em países de língua portuguesa em cães com osteoartrite.(AU)

We aimed to determine validity, reliability, and sensitivity of Helsinki's chronic pain index (HCPI) and stablish a correlation between HCPI in dogs with hip dysplasia (HD) using pressure sensitive walkway. Forty-owners of dogs with HD and 16 owners of health dogs filled a questionnaire. Dogs with HD were treated with carprofen 4.4mg/kg (GT n= 21) or with placebo (GP n= 19), both were administered once a day for 4 weeks. Evaluation was performed by the owners using the questionnaire (HCPI), the Visual Analogue Scale for pain (VASpain) and the VAS for locomotion (VASloc). The evaluation was performed 2 weeks before the treatment began (A1), immediately after treatment (A2), two (S2), four (S4) and two weeks after the end of treatment (S6) and the lameness was evaluated by pressure sensitive walkway. The internal consistency of the data was considered excellent (Cronbach´α coefficient= 0.89). There was a moderate correlation between the HCPI and VASpain. For VASloc the correlation was good. However, there was no difference between treatments, indicating low sensibility. No correlation was observed between pressure sensitive walkway and HCPI. We concluded that the questionnaire has construct and criterion validity, reliability and can be applied in dogs with osteoarthritis in Portuguese-speaking countries.(AU)

Characterisation of the in vivo interactions between detomidine and methadone in horses: Pharmacokinetic and pharmacodynamic modelling.

BACKGROUND: Pharmacokinetic (PK)/pharmacodynamic (PD) modelling offers new insights to design protocols for sedation and analgesia in standing horses. OBJECTIVES: To evaluate the parameters and interactions between detomidine and methadone when given alone or combined in standing horses. STUDY DESIGN: Randomised, placebo-controlled, blinded, crossover. METHODS: Eight adult healthy horses were given six treatments intravenously: saline (SAL); detomidine (5 µg/kg bwt; DET); methadone (0.2 mg/kg bwt; MET) alone or combined with detomidine (2.5 [MLD], 5 [MMD] or 10 [MHD] µg/kg bwt). Venous blood samples were obtained at predetermined times between 0 and 360 min after drug administration. Plasma detomidine and methadone were measured using a single, liquid/liquid extraction technique by liquid chromatography coupled with a triple quadrupole mass spectrometer (LC-MS/MS). Sequential PK/PD modelling compared rival models, with and without PK and PD interaction between drugs, to fit the PD data including height of the head above the ground (HHAG), a visual analogue scale for sedation (VAS), electrical (ET), thermal (TT) and mechanical (MT) nociceptive thresholds and gastrointestinal motility (GIM) [1]. RESULTS: Two and three compartment models best described the PK of detomidine and methadone, respectively. Detomidine decreased its own clearance as well as the clearance of methadone. The interaction of methadone on the effect of detomidine revealed an infra-additive (partial antagonism) effect for HHAG (α = -1.33), VAS (α = -0.98) and GIM (α = -1.05), a positive potentiation for ET (pot = 0.0041) and TT (pot = 0.133) and a synergistic to additive effect for MT (α = 0.78). MAIN LIMITATIONS: This is a small experimental study. CONCLUSIONS: Different PK/PD interactions were demonstrated for each PD parameter and could be modelled in vivo. The modelling of our data will allow us to simulate and predict the effect of constant rate infusions of both drugs for future investigations.

Sedative and antinociceptive effects of different detomidine constant rate infusions, with or without methadone in standing horses.

BACKGROUND: Standing surgery avoids the risks of general anaesthesia in horses. OBJECTIVES: To assess sedation, antinociception and gastrointestinal motility in standing horses after a detomidine loading dose and 2-h constant rate intravenous (i.v.) infusion, with or without methadone. STUDY DESIGN: Blinded, randomised, crossover with seven healthy adult cross-bred horses, three geldings and four females (404 ± 22 kg). METHODS: Five i.v. treatments were administered to all horses with 1-week washout period: saline (SAL), detomidine low (2.5 µg/kg bwt + 6.25 µg/kg bwt/h) (DL) and high doses (5 µg/kg bwt + 12.5 µg/kg bwt/h) (DH) alone or combined with methadone (0.2 mg/kg bwt + 0.05 mg/kg bwt/h), (DLM) and (DHM), respectively. Height of head above the ground (HHAG), electrical (ET), thermal (TT) and mechanical (MT) nociceptive thresholds and gastrointestinal motility were evaluated at predetermined times between 5 and 240 min. A mixed effect model and Kruskal-Wallis test were used to analyse normally and non-normally distributed data, respectively. RESULTS: Sedation (<50% basal HHAG) was achieved for the duration of the infusion, and for an additional 15 min in DH and DHM groups. Nociceptive thresholds were higher than baseline, to the greatest degree and the longest duration, with DHM (ET and TT for 135 min and MT for 150 min). After DH, TT was significantly higher than baseline from 30 to 120 min and MT from 15 to 135 min. After DLM, ET was increased at 90 min, TT at 30 min and MT for 120 min. Gastrointestinal motility was reduced for up to 135 min after DL, 150 min after DLM and 210 min after DH and DHM. MAIN LIMITATIONS: Nociceptive thresholds are not equivalent to surgical stimuli. CONCLUSION: Methadone with the highest detomidine dose (DHM) may provide sufficient sedation and analgesia for standing surgical procedures and warrants further investigation.

Is there a place for dexmedetomidine in equine anaesthesia and analgesia? A systematic review (2005-2017).

The objective of this review was to perform a literature compilation of all the equine publications that used dexmedetomidine as the first article on this topic was published, in 2005. We also aimed to answer the question whether the use of dexmedetomidine can currently be justified. For that, we compiled information from databases, such as PubMed, Google Scholar and Web of Science and the proceedings of the last veterinary anaesthesiology meetings. Dexmedetomidine is an attractive drug to be used in horses, mainly due to its pharmacokinetic profile and pharmacodynamics that favour its use as intravenous constant rate infusion (CRI). Nowadays, its clinical use is popular for sedation in prolonged standing procedures and during partial intravenous anaesthesia (PIVA) and total intravenous anaesthesia (TIVA). However, legal requirements for its use should be taken into account.

Pharmacokinetics and pharmacodynamics of the injectable formulation of methadone hydrochloride and methadone in lipid nanocarriers administered orally to horses.

We investigated the thermal, electrical and mechanical antinociceptive and physiological effects (heart rate, respiratory rate, arterial blood pressure, head height and abdominal auscultation score), and pharmacokinetics, of 0.5 mg/kg of the injectable formulation (ORAL) or nanoparticulated methadone (NANO) given orally, in six adult mares, using a crossover, blind and prospective design. Repeated-measure models were used to compare parametric data between and within treatments, followed by Tukey's test. Nonparametric data were analysed with Wilcoxon signed-rank, adjusted by Bonferroni tests. Blood samples were also collected up to 6 h after dosing for plasma drug quantification by LC-MS/MS. Methadone pharmacokinetic parameters were determined by noncompartmental and compartmental approaches. There were no differences in pharmacodynamic parameters. No statistical differences were observed in the pharmacokinetic parameters from noncompartmental analysis for both groups, except a significant decrease in peak plasma concentration, increase in apparent volume of distribution per fraction absorbed (Vdss /F) and increased mean residence time (MRT) for NANO. One-compartment open model with first order elimination best described the pharmacokinetic profiles for both groups. Neither ORAL nor NANO administered orally to horses produced antinociception. The nanoencapsulated formulation of methadone given orally to horses did not improve methadone pharmacokinetic parameters or increased systemic body exposure to methadone.

Antinociceptive effects of methadone combined with detomidine or acepromazine in horses.

REASONS FOR PERFORMING STUDY: To investigate two protocols to provide antinociception in horses. OBJECTIVES: To evaluate the antinociceptive effects of intravenous methadone combined with detomidine or acepromazine in adult horses. STUDY DESIGN: Randomised, blinded, crossover study. METHODS: Mechanical, thermal and electrical stimuli were applied to the dorsal left and right metacarpus and coronary band of the left thoracic limb, respectively. A thermal stimulus was applied caudal to the withers. The horses were treated with saline (C), a combination of methadone (0.2 mg/kg bwt) and detomidine (10 µg/kg bwt) (MD) or methadone (0.2 mg/kg bwt) and acepromazine (0.05 mg/kg bwt) (MA) at 1 week intervals. Nociceptive thresholds were measured before and at 15 min intervals until 150 min after treatment. Wilcoxon rank-sum and Wilcoxon signed rank tests were used to compare data between groups at each time point and over time within each group, followed by the Bonferroni method to adjust the P value. RESULTS: The mechanical stimulus was the most sensitive test to differentiate the antinociceptive effects of the treatments. Mechanical thresholds were greater after MD than MA between 15 and 30 min and with both MD and MA these thresholds were greater than C from 15 to 60 min. Electrical and thermal limb thresholds were greater after MD than C at 15 and 45 min and at 15, 30, 45, 75 and 105 min, respectively. Thermal limb thresholds were greater with MA than C at 30 min. Thoracic thermal threshold in MD and MA were higher than C at 45, 75, 90 and 120 min and from 30 to 75 min, respectively. CONCLUSIONS: Methadone and acepromazine produced less pronounced mechanical antinociception than MD.

Long-term weight gain and economic impact in pigs castrated under local anaesthesia.

Castration is a controversial practice in swine production because in some countries is still performed without anaesthesia, and therefore causes intense suffering and stress to animals. This study investigated the effect of pre-surgical administration of local anaesthesia (LA) on the growth performance of piglets until the end of the growth phase (102 days). Piglets aged 3 to 5 days were selected in pairs of similar weights and same age. They were originated from 22 litters. The groups were randomly assigned to one of two treatments. Castration was performed with (LA; n = 45) or without (NLA; n = 45) intra-testicular administration of 0.5 mL of 2% lidocaine plus adrenaline per testicle, administered by an automatic repeating vaccinator. Castration was performed 10 min later. Average daily weight gain and economic impact were evaluated between the intervals before castration until 21 (weaning phase), before castration until 60 (end of the initial nursery phase) and before castration until 102 (growth phase) days of age. Average daily weight gain data were analyzed by comparing the average daily weight gain between the weaning phase, 60 and 102 days of age versus the initial weight (pre-castration). At the end of the growing phase, animals treated with LA showed greater weight gain than animals castrated without anaesthesia. LA also showed improved cost:benefit ratio and theore might provide greater economic benefit under the conditions used in this study. Our findings have proved that castration with LA improves long-term weight gain of piglets.

Validation of mechanical, electrical and thermal nociceptive stimulation methods in horses.

REASONS FOR PERFORMING STUDY: To validate a model for investigating the effects of analgesic drugs on mechanical, thermal and electrical stimulation testing. OBJECTIVES: To investigate repeatability, sensitivity and specificity of nociceptive tests. STUDY DESIGN: Randomised experiment with 2 observers in 2 phases. METHODS: Mechanical (M), thermal (TL) and electrical (E) stimuli were applied to the dorsal metacarpus (M-left and TL-right) and coronary band of the left thoracic limb (E) and a thoracic thermal stimulus (TT) was applied caudal to the withers in 8 horses (405 ± 43 kg). Stimuli intensities were increased until a clear avoidance response was detected without exceeding 20 N (M), 60°C (TL and TT) and 15 V (E). For each set of tests, 3 real stimuli and one sham stimulus were applied (32 per animal) using a blinded, randomised, crossover design repeated after 6 months. A distribution frequency and, for each stimulus, Chi-square and McNemar tests compared both the proportion of positive responses detected by 2 observers and the 2 study phases. The κ coefficients estimated interobserver agreement in determining endpoints. Sensitivity (384 tests) and specificity (128 tests) were evaluated for each nociceptive stimulus to assess the evaluators' accuracy in detecting real and sham stimuli. RESULTS: Nociceptive thresholds were 3.1 ± 2 N (M), 8.1 ± 3.8 V (E), 51.4 ± 5.5°C (TL) and 55.2 ± 5.3°C (TT). The level of agreement after all tests, M, E, TL and TT, was 90, 100, 84, 98 and 75%, respectively. Sensitivity was 89, 100, 89, 98 and 70% and specificity 92, 97, 88, 91 and 94%, respectively. CONCLUSIONS: The high interobserver agreement, sensitivity and specificity suggest that M, E and TL tests are valid for pain studies in horses and are suitable tools for investigating antinociceptive effects of analgesics in horses.

Comparison of intrarectal ozone, ozone administered in acupoints and meloxicam for postoperative analgesia in bitches undergoing ovariohysterectomy.

Since all analgesics currently available for use in dogs have been associated with some adverse effects, the search for an effective analgesic that does not cause harm is important. This study investigated the postoperative analgesic effects of ozone administered either intrarectally or into acupoints in bitches undergoing ovariohysterectomy (OH). Twenty-four healthy adult bitches were randomly assigned to one of the three treatments 10 min after sedation, as follows: 0.2mg/kg of intramuscular (IM) meloxicam (M); rectal insufflation of 10 mL of 30 µg/mL ozone (OI), or acupoint injection of 0.5 mL ozone (30 µg/mL; OA). Following sedation with acetylpromazine, anaesthesia was induced with propofol and fentanyl and maintained with isoflurane/O2. Pain was assessed using the modified Glasgow pain scale (MGPS) and the visual analogue scale (VAS) on the day before surgery, before anaesthesia, and at 1, 2, 4, 6, 8, 12 and 24h after surgery. Rescue analgesia was performed using 0.5mg/kg of morphine IM if MGPS was >3.33 points. No statistically significant differences in pain scales were found among the three analgesic protocols or the time points in each group (P>0.05). Two dogs treated with OA required rescue analgesia. Meloxicam, rectal insufflation of ozone and ozone injected into acupoints provided satisfactory analgesia for 24h in bitches undergoing elective OH. Ozone had no measurable adverse effects and is an alternative option to promote pain relief.

Confiabilidade e pontuação mínima relacionada à intervenção analgésica de uma escala multidimensional para avaliação de dor pós-operatória em gatos / Reliability and cut-off point related to the analgesic intervention of a multidimensional composite scale to assess postoperative pain in cats

Avaliou-se a confiabilidade e determinou-se a pontuação mínima relacionada à necessidade de intervenção analgésica de uma escala multidimensional para avaliação de dor pós-operatória em gatas submetidas à ovário-histerectomia. Trinta gatas foram filmadas em quatro momentos predeterminados: pré-operatório, pós-operatório antes e depois da analgesia de resgate e às 24 horas após a cirurgia. Quatro observadores, não cientes dos momentos de avaliação, e um observador, considerado padrão-ouro - pesquisador que desenvolveu a escala - , avaliaram os vídeos em ordem aleatória, a partir da aplicação da escala, e determinaram a suficiência ou não de analgesia, baseando-se na experiência clínica. Os vídeos foram reavaliados dois meses após a primeira análise. O grau de concordância entre as avaliações dos diferentes observadores e das avaliações feitas pelo mesmo observador em diferentes ocasiões foi verificado pelo coeficiente de correlação intraclasse, que variou entre bom e muito bom para todos os itens da escala, exceto atividade, atitude e miscelânea de comportamentos que apresentaram confiabilidade moderada. O ponto de corte ótimo (> 7) foi selecionado pela análise descritiva e da curva Receiver Operating Characteristic. Os resultados suportam a confiabilidade em termos de reprodutibilidade e estabilidade e indicam que a terapia analgésica deve ser considerada em pontuações >8.

The aim with this study was to evaluate the reliability, and to establish the minimum score relating to the analgesic intervention of a multidimensional scale for use in assessing postoperative pain in cats undergoing ovariohysterectomy. Thirty cats were video recorded at 4 predetermined moments: prior to surgery, before and after rescue analgesia postoperatively, and 24 hours after surgery. Four observers blind to the times of assessment, and a gold standard observer (researcher who developed the scale) evaluated the video segments in random order using the scale, and determined the adequacy or not of analgesia based on clinical experience. The videos were reassessed two months after the first analysis. The agreement between the assessment of different observers, and the assessment made by the same observer on different occasions has been verified by the intra-class correlation coefficient that ranged from good to very good for all scale items, except activity, attitude and miscellaneous behaviors, which showed moderate reliability. The optimal cutoff point (> 7) was selected based on descriptive analysis and Receiver Operating Characteristic curve. The findings support the reliability in terms of reproducibility and stability, and indicate that analgesic therapy should be considered in scores >8.

Validade e responsividade de uma escala multidimensional para avaliação de dor pós-operatória em gatos / Validity and responsiveness of a multidimensional composite scale to assess postoperative pain in cats

O manejo adequado da dor depende de métodos de avaliação acurados. O objetivo deste estudo foi avaliar a validade e a responsividade de uma escala multidimensional para avaliação de dor pós-operatória em gatas submetidas à ovário-histerectomia. Trinta gatas foram filmadas no período perioperatório em quatro momentos predeterminados: pré-operatório, pós-operatório antes e depois da analgesia de resgate e às 24 horas após o término da cirurgia. Cinco observadores não cientes dos momentos de avaliação e um observador considerado padrão-ouro (pesquisador que desenvolveu a escala) avaliaram os vídeos em ordem aleatória e determinaram os escores de dor dos animais, utilizando a escala a ser validada. A responsividade e a validade de conteúdo e constructo foram estabelecidas pelo aumento e pela redução significativa nos escores de dor, em resposta ao procedimento cirúrgico e à administração de analgesia de resgate, respectivamente, avaliados pelo teste de Wilcoxon (P<0,001). A validade de critério foi atestada pela concordância alta entre as avaliações do padrão-ouro com os demais observadores, analisada pela porcentagem de absoluta concordância e coeficiente Kappa ponderado. Os resultados suportam a validade e a responsividade de uma escala multidimensional para avaliação de dor aguda pós-operatória em gatas submetidas à ovário-histerectomia, quando utilizada por veterinários formados e com experiência clínica.

Adequate pain management depends on accurate assessment methods. The aim of this study was to evaluate the validity and responsiveness of a multidimensional composite scale for use in assessing postoperative pain in cats undergoing ovariohysterectomy. Thirty cats were video recorded in four predetermined moments during the perioperative period: prior to surgery, before and after rescue analgesia postoperatively, and 24 hours after the end of surgery. Five observers blind to the times of assessment, and a gold standard observer (researcher who developed the scale) viewed the video segments in a random order, and the cat's pain scores were registered using the scale to be validated. The content and construct validity, and the responsiveness were established based on significant increase and reduction in the pain scores, in response to surgery and analgesics administration, respectively (Wilcoxon signed rank test, P<0.001). Criterion validity was determined by high agreement between the evaluations of the gold standard with the other observers, assessed by the percentage of absolute agreement and weighted Kappa coefficient. The findings support the validity and the responsiveness of a multidimensional composite scale to assess postoperative acute pain in cats undergoing ovariohysterectomy, when used by veterinarians with clinical experience.

Antinociceptive effects of epidural buprenorphine or medetomidine, or the combination, in conscious cats.

The aim of this study was to compare the antinociceptive effects of epidural buprenorphine (EB), epidural medetomidine (EM) or epidural buprenorphine-medetomidine (EBM). Eight cats were studied. Thermal thresholds (TT) were measured by increasing the temperature of a probe placed on the thorax. Mechanical thresholds (MT) were measured through inflation of a modified blood pressure bladder to the cat's forelimb. After baseline measurements, EB (0.02 mg/kg), EM (0.01 mg/kg) or half of the doses of each drug (EBM) were administered. Data were analysed using anova (P < 0.05) and 95% confidence interval (CI). TT increased from 30 min to 1 h after EB and at 45 min after EM. MT increased from 45 min to 2 h after EB, from 15 min to 1 h after EM and at 30, 45 min and at 2 h after EBM. MT were significantly lower after EB than EM at 30 min. TT were above the upper 95%CI from 15 min to 24 h after EB, from 15 min to 4 h after EM and from 15 min to 8 h after EBM. MT were above the upper 95%CI from 15 min to 5 h, and at 8, 12 and 24 h after EB, from 15 min to 6 h after EM and from 15 min to 6 h and at 12 and 24 h after EBM. All treatments had similar onset. Overall, EB presented longer period of action than EBM and EM. The same magnitude of analgesia was achieved, but with fewer side effects when EBM was compared with EM.

Comparação entre a lidocaína e a acupuntura no tratamento da taquicardia ventricular induzida com dopamina em equinos anestesiados com halotano / Comparative study between lidocaine and acupunture in the treatment of ventricular tachycardia induced by dopamine in horses anesthetized with halothane

Os efeitos da lidocaina e da acupuntura nos pontos bilaterais associados ao pericárdio 6 (Pc6-Neiguan) e ao coração 7 (C7-Shenmen), no tratamento da taquicardia ventricular (TV) induzida por dopamina em equinos anestesiados com halotano, foram avaliados e comparados. Seis equinos, distribuídos em três grupos: grupo-controle (GC), grupo tratado com acupuntura (GA) e grupo tratado com lidocaína (GL), foram anestesiados três vezes cada, com intervalo de uma semana entre cada anestesia. Avaliaram-se os parâmetros cardiovasculares (frequência cardíaca, pressão arterial e eletrocardiografia), os respiratórios (frequência respiratória, capnografía, saturação de hemoglobina e hemogasometria) e o escore de recuperação. A dose arritmogênica da dopamina (DAD) foi determinada a partir da infusão de 70µg/kg/min IV durante 10 minutos, sem interrupção, preenchendo o critério arritmogênico: quatro ou mais complexos ventriculares prematuros seguidos, com duração de pelo menos 15 segundos ou TV sustentada. O tempo médio de aparecimento da DAD ou da TV foi de 6,05±0,45 minutos nos animais não tratados, e a TV se reverteu espontaneamente aos 2,7±0,2 minutos. O grupo tratado com acupuntura reverteu a TV no tempo médio de 1,8±0,2 (P<0,05) em relação ao grupo tratado com lidocaina 1,3±0,2 (P<0,01). Os tratamentos mostraram-se eficientes na reversão TV.

The effects of lidocaine and acupuncture in the associated bilateral points, i.e. pericardium 6 (Pc 6- Neiguan) and heart 7 (H7 - Shenmen), on the ventricular tachycardia (VT) induced by dopamine were evaluated in horses anesthetized with halothane. Six horses were distributed in three groups: control group (CG), acupuncture treated group (AG), and lidocaine treated group (LG). They were anesthetized three times each one using halothane with one week interval between each anesthesic procedure. Cardiovascular (heart rate, arterial pressure, and ECG) and respiratory (respiratory rate, capnometry, hemoglobin saturation, and blood gas analysis) parameters and recovery score were evaluated. The arrhythmogenic dose of dopamine (ADD) was determined by the infusion of 70mg/kg/min during 10 minutes without interruption fulfilling the arrhythmogenic criterion by the presence of four or more ectopic ventricular contractions during at least 15 seconds or maintained VT. The mean time for the occurrence of ADD or VT was 6.05 ± 0.45 minutes in no treated animals and the VT reverted spontaneously in 2.7 ± 0.2 minutes. The group treated with acupuncture reverted the VT in a mean time of 1.8 ± 0.2 (P<0.05) compared to the group treated with lidocaine 1.3±0.2 (P<0.01), both of them were efficacious for the treatment of VT.

Evaluation of the adverse effects of oral firocoxib in healthy dogs.

This study evaluated the adverse effects of oral firocoxib in dogs. Six dogs (20.2+/-6.3 kg) were studied. Values for complete blood count (CBC), serum urea, creatinine, alanine transaminase, alanine phosphatase, gamma-glutamyl transferase, occult blood in feces, platelet aggregation, and buccal mucosal bleeding time were measured before and 7, 14, 21, and 29 days after SID treatment with firocoxib 5.3+/-0.34 mg/kg (FG) or lactose 1 mg/kg (LG) for 28 days, in a randomized crossover study. Gastrointestinal (GI) tract endoscopy was performed before treatment began and at 29 days. Lesions were scored from grade 0 to 6. Data were analyzed using anova and paired t-tests (P<0.05). None of the dogs presented adverse clinical effects. There were no significant changes in CBC, biochemical profiles within groups, or differences between groups. Pretreatment mean+/-SD bleeding time (LG, 70.7+/-32.1 sec; FG, 75.8+/-38.1 sec) and platelet aggregation (LG, 86.4+/-10.2%; FG, 85.6+/-9.2%) were not significantly different from readings at 29 days (LG, 95.2+/-25 sec; FG, 91.7+/-24 sec and LG, 73.2+/-15.1%; FG, 84+/-10.3%) nor the groups were different. None of the dogs had positive fecal occult blood tests, and endoscopic lesion scores were grade 0 both before treatment and at 29 days. Administration of firocoxib did not cause any adverse effects on GI, or hematological or serum biochemical variables and appears to have been well tolerated by dogs.

Carprofen and buprenorphine prevent hyperalgesia in a model of inflammatory pain in cats.

A model of nociceptive threshold determination was developed for evaluation of NSAID analgesia in cats. In a crossover study, eight cats received carprofen (4 mg/kg), buprenorphine (0.01 mg/kg) or saline (0.3 ml) subcutaneously before intradermal kaolin injection on the antebrachium to induce mild inflammation. Pressure thresholds were measured at the injected site using blunt-ended pins advanced by manual inflation of a bladder within a bracelet. Bladder pressure was recorded as threshold (PT) at the behavioural end point. Baseline PT were recorded before kaolin injection (time 0). PT was measured at 2-10 h intervals for 52 h. PT below the lower 95% confidence interval (CI) of baseline values indicated hyperalgesia. After saline, hyperalgesia was detected from 2-6 h, 22-26 h, and at 30 and 36 h. After carprofen, PT remained within the 95% CI. After buprenorphine, PT remained within the 95% CI except at 2h. Carprofen and to some extent buprenorphine, prevented inflammatory hyperalgesia.

Development of a pressure nociceptive threshold testing device for evaluation of analgesics in cats.

A pressure analgesiometric device was developed for unrestrained cats. Eleven cats were studied. Stimulation was via three rounded pins within a bracelet on the forearm. The pins were advanced by manual bladder inflation. Bladder pressure was measured using a strain gauge pressure transducer. The threshold was recorded at the behavioural end point. Thresholds were measured at 5 and 15min intervals for 2-4h, after removal/replacement of the cuff, for 120min after SC butorphanol (0.4mg/kg), and with mild skin inflammation at the testing site. Data were analysed using ANOVA. Pressure thresholds in untreated cats were around 150mmHg. The minimum interval for testing was established as 15min. Data were reproducible over 4h and beyond 24h. Thresholds in 5 cats increased (P<0.05) above baseline for 45min after butorphanol with a maximum increase of 270+/-182mmHg at 10min. Thresholds decreased with inflammation. The method appears suitable for feline analgesia investigations.