Anestesia peribulbar com ropivacaína como alternativa ao bloqueio neuromuscular para facectomia em cães Peribulbar anesthesia with ropivacaine as an alternative to neuromuscular blocking agents for cataract surgery in dogs

Desenvolveu-se uma técnica de bloqueio peribulbar comparando-a à técnica de anestesia oftálmica com bloqueio neuromuscular parcial em cães submetidos à facectomia extracapsular. Doze cães, de diferentes raças, foram alocados em dois grupos (G1 e G2) e anestesiados com acepromazina (0,05mg/kg, IV) e propofol (5mg/kg, IV) e mantidos com isofluorano sob ventilação espontânea. Os cães do G1 receberam o bloqueio peribulbar com ropivacaína 0,75%, e os do G2 o bloqueio neuromuscular parcial com brometo de pancurônio (0,01mg/kg, IV). Utilizaram-se, como parâmetros comparativos, escores de posicionamento do globo ocular, controle do reflexo oculocardíaco e pressão intraocular (mmHg). Foi possível propor uma técnica eficaz para cães baseando-se na técnica de bloqueio peribulbar posterior realizada no homem. Em ambos os grupos, o globo ocular permaneceu centralizado. Não ocorreram alterações eletrocardiográficas atribuídas ao reflexo oculocardíaco. Houve redução significativa da pressão intraocular em G1 após o bloqueio (10,7±0,6 e 14,7±0,6). Conclui-se que o bloqueio peribulbar proporcionou condições cirúrgicas apropriadas para a realização da facectomia, com a vantagem de promover bloqueio sensitivo do olho.A peribulbar block technique was developed and its clinical efficacy was compared with neuromuscular blockade in dogs undergoing cataract surgery. Twelve dogs of different breeds were randomly and equally allocated in two groups. After given acepromazine (0.05mg/kg, IV), anesthesia was induced with propofol (5mg/kg, IV) and maintained with isoflurane in oxygen during spontaneous breathing. A peribulbar block with 0.75% ropivacaine was performed in G1 dogs while partial neuromuscular blockade with pancuronium (0.01mg/kg IV) was provided in G2 dogs. Globe position scores, oculocardiac reflex, and intra-ocular pressure (mmHg) were evaluated at pre-defined intervals during surgery. Peribulbar blocks were successful performed according to posterior peribulbar block described in humans. In both groups, the globe was centralized and globe position scores did not differ between groups. The intra-ocular pressure was significantly lower in G1 after the block (10.7±0.6 vs 14.7±0.6). There were no electrocardiographycal changes attributed to the oculocardiac reflex. In conclusion, satisfactory surgical conditions were provided by the peribulbar block. This technique can be used as an alternative to the use of neuromuscular blocking agents in dogs undergoing cataract surgery, with the advantage of providing analgesia of the eye

Anestesia local por tumescência com lidocaína em cadelas submetidas a mastectomia

The present study investigated the benefits of tumescent anesthesia with lidocaine in dogs undergoing mastectomy, seeking the patients' comfort and their postoperative recovery. Seven animals, with different weight and breed, who had cancer in the region of mammary chain underwent mastectomy surgery. All animals received the same anesthetic protocol being used as the association between acepromazine and morphine doses of 0.04mg.kg-1 and 0.4mg.kg-1 (IM), respectively. After 15 minutes a catheter was placed in the cephalic vein and induction with propofol 4mg.kg-1 and 0.2mg.kg-1 followed by maintenance with isoflurane anesthesia was done. After instrumentation, we proceeded to the tumescent anesthesia technique with ice-cold solution consisting of Ringer's lactate, lidocaine 2% without epinephrine and adrenaline in a total volume of 15mL.kg-1. The average duration of the procedure was 74±18 minutes. The plasmatic peak of lidocaine was between 30 and 60 minutes after infiltration. The rescue analgesic was performed after approximately seven hours of infiltration. It can be concluded that the tumescent anesthesia with lidocaine should be considered as a constituent of anesthetic and analgesic protocol in dogs undergoing mastectomy surgery providing parameter stability, safety and good quality postoperative recovery.O presente estudo investigou os benefícios da anestesia por tumescência com lidocaína em cadelas submetidas à mastectomia, visando ao conforto do paciente e à sua recuperação pós-operatória. Foram utilizados sete animais, de peso e raças variadas, que apresentavam neoplasia em região de cadeia mamária e que foram submetidos à cirurgia de mastectomia. Todos os animais receberam o mesmo protocolo anestésico, sendo utilizado como MPA a associação entre acepromazina e morfina, nas doses de 0,04mg/kg e 0,4mg/kg (IM), respectivamente. Após 15 minutos, foi alocado um cateter em veia cefálica e realizou-se a indução com propofol 4mg/kg e midazolam 0,2mg/kg, seguida de manutenção anestésica com isofluorano. Posteriormente à instrumentação, procedeu-se à técnica de anestesia por tumescência com solução gelada composta por ringer lactato, lidocaína 2% sem vasoconstritor e adrenalina, em um volume total de 15mL/kg. Em média, o tempo de duração do procedimento foi de 74±18 minutos. O pico plasmático de lidocaína deu-se entre 30 e 60 minutos após a infiltração da solução. O resgate analgésico foi realizado após sete horas, aproximadamente, da infiltração. Pode-se concluir que a anestesia por tumescência com lidocaína deve ser considerada como constituinte do protocolo anestésico e analgésico de cadelas a serem submetidas à cirurgia de mastectomia, proporcionando estabilidade de parâmetros, segurança e recuperação pós-operatória de boa qualidade

Epidural levobupivacaine alone or combined with different morphine doses in bitches under continuous propofol infusion

The aim of this study was to assess the cardiopulmonary, analgesic, adverse effects, serum concentration of cortisol and plasma levels of levobupivacaine and morphine in bitches undergoing propofol anesthesia and epidural analgesia with levobupivacaine alone or combined with morphine. This was a randomized 'blinded' prospective clinical study using 32 adult bitches weighing 9.8±4.1kg that were admitted for elective ovariohysterectomy. Twenty minutes after administration of acepromazine and midazolam, anesthesia was induced with propofol (4mg kg-1) and maintained by a continuous rate infusion (CRI). Each animal was randomly assigned to one of four epidural groups: GL = levobupivacaine alone (0.33mg kg-1); GLM0.1 = levobupivacaine and morphine (0.1mg kg-1); GLM0.15 = levobupivacaine and morphine (0.15mg kg-1); and GLM0.2 = levobupivacaine and morphine (0.2mg kg-1). Variables obtained during anesthesia were heart rate, respiratory rate, systolic, mean and diastolic arterial blood pressures, oxyhemoglobin saturation, inspired oxygen fraction, end-tidal carbon dioxide tension, blood gases, serum cortisol, and plasma levels of levobupivacaine and morphine. The onset and duration times of the blockade were recorded. Arterial pressures were significantly increased in all groups at the times of ovarian pedicle clamping. There was a decrease in pH, together with an increase in both PaO2and PaCO2 over time. Serum cortisol levels were increased in TESu compared to TB, T30 and TR. Limb spasticity, muscle tremors, opisthotonos and diarrhea were observed in some animals during propofol infusion and ceased with the end of CRI. Reactions happened at different moments and lasted for different periods of time in each individual. Epidural with levobupivacaine alone or combined with morphine allowed for ovariohysterectomy to be performed under low propofol infusion rates, with minimal changes in cardiovascular variables and in serum cortisol levels. Adverse effects were observed in very few animals in each group

Avaliação fisiológica e comportamental de cães utilizados em terapia assistida por animais (TAA)

Realizou-se a observação comportamental de nove cães terapeutas (oito da raça Labrador Retriever e um Golden Retriever), dosaram-se cortisol sérico e salivar, aferiram-se a temperatura retal, a pressão arterial sistólica e as frequências cardíaca e respiratória nos seguintes momentos: M0 (média de três avaliações do cão em repouso) e em M1, M2 e M3 (imediatamente antes, imediatamente após e decorridas 24h das atividades de terapia assistida por animais - TAA), respectivamente. Não houve diferença significativa quanto às características estudadas (P>0,05), exceto pela temperatura, que foi mais elevada em M1 e M2 do que em M0 (P=0,009). A avaliação comportamental, realizada de maneira descritiva, não apresentou alteração negativa. Houve diferença significativa quanto à concentração de cortisol sérico entre os momentos M1 e M3 (P=0,071), e não ocorreu diferença da concentração do cortisol salivar entre os quatro momentos (P=0,746). As alterações observadas foram atribuídas à contenção e à manipulação dos animais e não desencadearam desconforto físico ou estresse dignos de nota em cães

Different rates of tramadol infusion for peri and postoperative analgesia in dogs undergoing orthopedic surgery

ABSTRACT The study aimed to determine the continuous rate infusion of tramadol associated with peri- and postoperative analgesia for orthopedic surgeries in dogs, as well as cardiorespiratory and adverse effects. Thirty dogs aged 4.2±1.2 years and weighing 15.1±0.9kg were enrolled in the study, premedicated intramuscularly with acepromazine (0.04mg kg-1) and tramadol (2mg kg-1); anesthesia was induced with propofol and maintained with isoflurane in oxygen. Three infusion rates were compared, comprising three experimental groups: G2: 2.0mg kg-1 h-1; G2.5: 2.5mg kg-1 h-1; and G3: 3.0mg kg-1 h-1. Surgery was initiated 15 minutes following the start of tramadol infusion. During anesthesia, animals were monitored in predefined time points: immediately after tracheal intubation and start of inhalation anesthesia (T0); surgical incision (TSI); final suture (TFS) and end of tramadol infusion (TEI), which was maintained for at least 120 minutes and prolonged according to the duration of surgery. Postoperative analgesia was evaluated through an interval pain scoring scale and the Melbourne pain scale. The mean time of tramadol infusion was greater than 120 minutes in all groups and no differences were found among them (141±27 minutes in G2, 137±27 minutes in G2.5 and 137±30 minutes in G3). Perioperative analgesia was regarded as short and did not correlate with infusion rates. Tramadol infusion provided adequate analgesia with cardiorespiratory stability Analgesia was not dose-dependent, however, and residual postoperative effects were short-lasting, which warrants proper postoperative analgesia following tramadol infusion. Additional studies are required using higher infusion rates and standardized nociceptive stimulation in order to determine how doses influence tramadol analgesia and whe therthereis a limit to its effect in dogs