Intravenous Tramadol Injection has no Antinociceptive Effect in Horses Undergoing Electrical and Thermal Stimuli

Tramadol combines an μ opiate and nonopiate analgesic mechanism and might be a useful opioid in horses. This study evaluated the effect of IV tramadol on spontaneous locomotor activity (SLA), head height, and hoof withdrawal reflex (HWR) after thermal or electrical nociceptive stimuli in horses. Doses of 2 and 3 mg/kg tramadol did not affect HWR after electrical and thermal nociception, respectively. Head height and SLA were not modified by 2, 3, or 5 mg/kg tramadol. All horses treated with 5 mg/kg tramadol developed trembling in pectoral triceps, and gluteal muscles and adopted a base-wide stance. In conclusion, 2 and 3 mg/kg tramadol IV neither induced sedation nor prolonged HWR after thermal or electrical stimuli in conscious horses. The dose of 5 mg/kg tramadol IV produced excitement, and it is apparently unsuitable for clinical use. © 2013 Elsevier Inc. All rights reserved.

Comparison of Epidural and Systemic Tramadol for Analgesia Following Ovariohysterectomy

The objective of the study was to compare epidural and systemic tramadol for postoperative analgesia in bitches undergoing ovariohysterectomy. Twenty animals, randomly divided into two groups, received either epidural (EPI) or intramuscular (IM) tramadol (2 mg/kg) 30 min before anesthetic induction. Analgesia, sedation, cardiorespiratory parameters, end-tidal isoflurane, blood catecholamines and cortisol, and arterial blood gases were measured at different time points up to 24 hr after agent administration. There were no differences between the two groups regarding cardiorespiratory parameters, end-tidal isoflurane, and pain scores. Two dogs in the IM and one in the EPI group required supplemental analgesia. Cortisol was increased (P<0.05) at 120 min (3.59 mu g/dL and 3.27 mu g/dL in the IM and EPI groups, respectively) and 240 min (2.45 mu g/dL and 2.54 mu g/dL in the IM and EPI groups, respectively) compared to baseline. Norepinephrine was also increased (P<0.05) at 120 min in both groups compared to baseline values. Epinephrine values were higher (P<0.05) in the IM group compared with the EPI group at 50 min, 120 min, and 1,440 min after tramadol administration. Epidural tramadol is a safe analgesic, but does not appear to have improved analgesic effects compared with IM administration. (J Am Anim Hosp Assoc 2012; 48:310-319. DOI 10.5326/JAAHA-MS-5795)

Tramadol and o-desmethyl tramadol clearance maturation and disposition in humans: a pooled pharmacokinetic study.

BACKGROUND AND OBJECTIVES We aimed to study the impact of size, maturation and cytochrome P450 2D6 (CYP2D6) genotype activity score as predictors of intravenous tramadol disposition. METHODS Tramadol and O-desmethyl tramadol (M1) observations in 295 human subjects (postmenstrual age 25 weeks to 84.8 years, weight 0.5-186 kg) were pooled. A population pharmacokinetic analysis was performed using a two-compartment model for tramadol and two additional M1 compartments. Covariate analysis included weight, age, sex, disease characteristics (healthy subject or patient) and CYP2D6 genotype activity. A sigmoid maturation model was used to describe age-related changes in tramadol clearance (CLPO), M1 formation clearance (CLPM) and M1 elimination clearance (CLMO). A phenotype-based mixture model was used to identify CLPM polymorphism. RESULTS Differences in clearances were largely accounted for by maturation and size. The time to reach 50 % of adult clearance (TM50) values was used to describe maturation. CLPM (TM50 39.8 weeks) and CLPO (TM50 39.1 weeks) displayed fast maturation, while CLMO matured slower, similar to glomerular filtration rate (TM50 47 weeks). The phenotype-based mixture model identified a slow and a faster metabolizer group. Slow metabolizers comprised 9.8 % of subjects with 19.4 % of faster metabolizer CLPM. Low CYP2D6 genotype activity was associated with lower (25 %) than faster metabolizer CLPM, but only 32 % of those with low genotype activity were in the slow metabolizer group. CONCLUSIONS Maturation and size are key predictors of variability. A two-group polymorphism was identified based on phenotypic M1 formation clearance. Maturation of tramadol elimination occurs early (50 % of adult value at term gestation).

Intrapleural analgesia after endoscopic thoracic sympathectomy

OBJETIVO: Comparar a analgesia tradicionalmente utilizada para simpatectomia videotoracoscópica à injeção intrapleural de ropivacaína em duas doses diferentes. MÉTODOS: Vinte e quatro pacientes foram distribuídos em três grupos semelhantes, e todos eles receberam dipirona endovenosa. O grupo A recebeu tramadol endovenoso e injeção intrapleural de solução salina. O grupo B recebeu injeção intrapleural de ropivacaína a 0,33%, e Grupo C ropivacaína a 0,5%. Os aspectos analisados foram: capacidade inspiratória, freqüência respiratória e dor. A dor foi avaliada no período pós-operatório por meio da escala visual analógica e durante o período de uma semana. RESULTADOS: Nos grupos A e B, a redução da capacidade inspiratória foi observada no período pós-operatório. Nas primeiras 12 horas de pós-operatório, apenas 12,5% dos pacientes nos grupos B e C apresentaram dor intensa em comparação a 25% no Grupo A. Na semana seguinte, apenas um paciente do grupo A apresentou dor leve, enquanto o restante relatou dor intensa. No Grupo B, metade dos pacientes apresentou dor intensa, e no Grupo C, apenas um apresentou intensa dor. CONCLUSÃO: A analgesia intrapleural com ropivacaína resultou em menos dor no pós-operatório tardio com os melhores resultados analgésicos nas doses mais altas, proporcionando um melhor padrão ventilatório.

Eficácia da N-butilescopolamina e dipirona sódica associadas ao cetoprofeno no alívio da dor pós-operatória de pacientes submetidas a duas técnicas diferentes de laqueadura por laparoscopia

JUSTIFICATIVA E OBJETIVOS: A laqueadura laparoscópica (LL) é um dos procedimentos mais dolorosos e a intensidade da dor varia com a técnica selecionada, sendo mais intensa com a técnica de oclusão das tubas uterinas com anel. As pacientes submetidas à LL referem dor em cólica no período PO e a N-butilescopolamina e a dipirona sódica, por suas propriedades anti-espasmódicas e analgésicas, associadas às propriedades antiinflamatórias do cetoprofeno, podem ser opção para profilaxia e tratamento de dor. O objetivo deste foi estudar a eficácia da N-butilescopolamina e da dipirona sódica associadas ao cetoprofeno, na prevenção de dor PO em pacientes submetidas à LL, com duas técnicas diferentes - diatermia e pinçamento com anel. MÉTODO: Participaram do estudo 50 pacientes, estado físico ASA I e II, com idade entre 23 e 47 anos. As pacientes foram distribuídas aleatoriamente em dois grupos: G1 - oclusão das tubas uterinas com anéis, G2 - oclusão das tubas uterinas com diatermia. Todas as pacientes receberam N-butilescopolamina (20 mg) e dipirona sódica (2500 mg) e cetoprofeno (100 mg), por via venosa, imediatamente antes da indução da anestesia. A dor foi avaliada pelo critério de escala numérica verbal, variando de 0 a 10, sendo 0 ausência de dor e 10 o máximo de dor, a cada 10 minutos na primeira hora, na sala de recuperação pós-anestésica (SRPA) e na 1ª, 2ª, 3ª e 4ª horas após a alta da SRPA. Dor com intensidade maior que 3 era tratada com tramadol (100 mg), por via venosa. A avaliação da dor foi realizada sem que se soubesse a que grupo pertencia a paciente. Para análise estatística, testes t de Student, Mann-Whitney e Friedman. RESULTADOS: Ambos os grupos foram idênticos com relação à idade, ao peso, à altura, à duração da cirurgia e anestesia. As pacientes do G1 apresentaram maior escore de dor que as do G2, em todos os momentos do estudo. Valores estatisticamente significativos: 80% das pacientes de G1 e 16% de G2 necessitaram de tramadol em algum momento do estudo. CONCLUSÕES: A N-butilescopolamina e a dipirona sódica associadas ao cetoprofeno mostraram ser alternativa de analgesia pós-operatória quando a laqueadura é realizada com a técnica de diatermia.

Comparative study on the sedative effects of morphine, methadone, butorphanol or tramadol, in combination with acepromazine, in dogs

To compare the effects of morphine (MOR), methadone (MET), butorphanol (BUT) and tramadol (TRA), in combination with acepromazine, on sedation, cardiorespiratory variables, body temperature and incidence of emesis in dogs.Prospective randomized, blinded, experimental trial.Six adult mixed-breed male dogs weighing 12.0 +/- 4.3 kg.Dogs received intravenous administration (IV) of acepromazine (0.05 mg kg(-1)) and 15 minutes later, one of four opioids was randomly administered IV in a cross-over design, with at least 1-week intervals. Dogs then received MOR 0.5 mg kg(-1); MET 0.5 mg kg(-1); BUT 0.15 mg kg(-1); or TRA 2.0 mg kg(-1). Indirect systolic arterial pressure (SAP), heart rate (HR), respiratory rate (f(R)), rectal temperature, pedal withdrawal reflex and sedation were evaluated at regular intervals for 90 minutes.Acepromazine administration decreased SAP, HR and temperature and produced mild sedation. All opioids further decreased temperature and MOR, BUT and TRA were associated with further decreases in HR. Tramadol decreased SAP whereas BUT decreased f(R) compared with values before opioid administration. Retching was observed in five of six dogs and vomiting occurred in one dog in MOR, but not in any dog in the remaining treatments. Sedation scores were greater in MET followed by MOR and BUT. Tramadol was associated with minor changes in sedation produced by acepromazine alone.When used with acepromazine, MET appears to provide better sedation than MOR, BUT and TRA. If vomiting is to be avoided, MET, BUT and TRA may be better options than MOR.

Efeitos do tramadol no modelo de dor induzida por obstrução intestinal em eqüinos

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diferentes taxas de infusão de tramadol na analgesia trans e pós-operatória imediata em cães submetidos a procedimentos ortopédicos: Thais Mayara Menegheti.-

Pós-graduação em Ciência Animal - FMVA

Parâmetros ventilométricos, cardiovasculares, hematológicos e índice biespectral, em cães anestesiados com infusão contínua de propofol, associado ou não ao tramadol

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Anestesia de suínos com azaperona, midazolam e propofol em associação ao tramadol ou não

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Função renal após colecistectomia por laparoscopia e analgesia com tramadol e dipirona ou cetorolaco

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos do tramadol isolado ou associado à xilazina em equinos

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Hematologic changes in propofol-anesthetized dogs with or without tramadol administration

Drugs commonly used in anesthesia practice may significantly alter the oxidative state of blood cells. This mechanism could contribute to the immune suppression that occurs transiently in the early postoperative period. Thus, we assessed the effects of continuous rate infusion (CRI) of propofol associated or not with tramadol on hematologic parameters in dogs. Eight adult mongrel dogs were anesthetized on 2 occasions, 15 d apart. Two groups were formed: control group (CG) and tramadol group (GT). Propofol was used for induction (10mg kg-1) followed by a CRI (0.7mg kg-1minute-1). The animals were positioned in lateral recumbency and mechanically ventilated with inspired oxygen fraction of 0.6. In TG, tramadol (2mg kg-1) followed by a CRI (0.5mg kg-1minute-1) was administered in dogs. In the CG the sodium chloride (NaCl) solution at 0.9% was administered followed by its CRI, in the same volume that was used in TG. The measurement was taken before anesthesia induction (Tbasal), 30 minutes after induction (T0) and then at 30-minute intervals (T30 to T60). Red blood cells, hematocrit, hemoblogin concentration and total leukocytes count decreased from T0 in both groups. In TG, lymphocytes count at Tbasal [1.86 (0.82) x103µl-1] was greater than at T0, T30 and T60 [0.96(0.50), 0.92(0.48) and 0.95(0.48) x103µl-1, respectively]. No significant differences were observed for platelets neutrophil, eosinophil, basophil and monocyte count. In dogs, propofol-anesthesia associated or not with tramadol promoted decrease in blood cell count and should be used with caution in immunossupressed patients.

Antagonistic effects of ondansetron and tramadol? A randomized placebo and active drug controlled study

Opposing effects of ondansetron and tramadol on the serotonin pathway have been suggested which possibly increase tramadol consumption and emesis when co-administered. In a randomized, double-blinded study, 179 patients received intravenous ondansetron, metoclopramide, or placebo for emesis prophylaxis. Analgesic regimen consisted of tramadol intraoperative loading and subsequent patient-controlled analgesia. Tramadol consumption and response to antiemetic treatment were compared. Additionally, plasma concentrations of ondansetron and (+)O-demethyltramadol and CYP2D6 genetic variants were analyzed as possible confounders influencing analgesic and antiemetic efficacy. Tramadol consumption did not differ between the groups. Response rate to antiemetic prophylaxis was superior in patients receiving ondansetron (85.0%) compared with placebo (66.7%, P = .046), with no difference to metoclopramide (69.5%). Less vomiting was reported in the immediate postoperative hours in the verum groups (ondansetron 5.0%, metoclopramide 5.1%) compared with placebo (18.6%; P = .01). Whereas plasma concentrations of (+)O-demethyltramadol were significantly correlated to CYP2D6 genotype, no influence was detected for ondansetron. Co-administration of ondansetron neither increased tramadol consumption nor frequency of PONV in this postoperative setting. PERSPECTIVE: Controversial findings were reported for efficacy of tramadol and ondansetron when co-administered due to their opposing serotonergic effects. Co-medication of these drugs neither increased postoperative analgesic consumption nor frequency of emesis in this study enrolling patients recovering from major surgery.

Continuous intravenous infusion of glucose induces endogenous hyperinsulinaemia and lamellar histopathology in Standardbred horses

Endocrinopathic laminitis is frequently associated with hyperinsulinaemia but the role of glucose in the pathogenesis of the disease has not been fully investigated. This study aimed to determine the endogenous insulin response to a quantity of glucose equivalent to that administered during a laminitis-inducing, euglycaemic, hyperinsulinaemic clamp, over 48. h in insulin-sensitive Standardbred racehorses. In addition, the study investigated whether glucose infusion, in the absence of exogenous insulin administration, would result in the development of clinical and histopathological evidence of laminitis. Glucose (50% dextrose) was infused intravenously at a rate of 0.68 mL/kg/h for 48. h in treated horses (n = 4) and control horses (n = 3) received a balanced electrolyte solution (0.68 mL/kg/h). Lamellar histology was examined at the conclusion of the experiment. Horses in the treatment group were insulin sensitive (M value 0.039 ± 0.0012. mmol/kg/min and M-to-I ratio (100×) 0.014 ± 0.002) as determined by an approximated hyperglycaemic clamp. Treated horses developed glycosuria, hyperglycaemia (10.7 ± 0.78. mmol/L) and hyperinsulinaemia (208 ± 26.1. μIU/mL), whereas control horses did not. None of the horses became lame as a consequence of the experiment but all of the treated horses developed histopathological evidence of laminitis in at least one foot. Combined with earlier studies, the results showed that laminitis may be induced by either insulin alone or a combination of insulin and glucose, but that it is unlikely to be due to a glucose overload mechanism. Based on the histopathological data, the potential threshold for insulin toxicity (i.e. laminitis) in horses may be at or below a serum concentration of ∼200. μIU/mL.