Analgesia perioperatória de gatas submetidas a ovariohisterectomia eletiva - uso preemptivo de carprofeno ou grapiprant / Perioperative analgesia in cats undergoing elective ovariohysterectomy - preemptive use of carprofen or grapiprant

Background: The nonsteroidal anti-inflammatory drugs (NSAIDs) exert their analgesic effect through peripheral inhibition of prostaglandin synthesis and a variety of other peripheral and central mechanisms. However, NSAIDs are associated with some adverse effects, mainly related to the gastrointestinal, renal, and hepatic systems, highlighting the need for research to develop safer drugs. Therefore, the aim of this study was to evaluate the efficacy of preoperative oral administration of carprofen or grapiprant in female cats submitted to elective ovariohysterectomy on the quality of perioperative analgesia and the need for hypnotic and analgesic drugs. Materials, Methods & Results: Thirty-three adult female cats were selected, without defined breed and healthy based on physical examination, routine laboratory analyses (complete blood count, total protein, Heinz body investigation and serum quantification of alanine transaminase [ALT], aspartate transaminase [AST], gamma glutamyl transpeptidase [GGT], alkaline phosphatase [ALP], urea, frutosamine, and glucose) and negative tests for feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV). After 3 days of adaptation, they were submitted to ovariohysterectomy by celiotomy and randomly allocated into 2 groups according to the preoperative drug used: GCAR [carprofen - 4 mg/kg, VO, 2 h before surgery; n = 11] and GGRA (grapiprant - 2 mg/kg IV, 2 h before surgery; n = 21]. The cats were pre-medicated with acepromazine 0.05 mg/ kg IV and later submitted to general anesthesia with propofol intravenously. Anesthesia was maintained with isoflurane in 100% oxygen. After anesthetic induction, a continuous infusion of remifentanil at a rate of 10 µg/kg/h was initiated. During the transanesthetic period, the parameters of heart rate; respiratory rate; systolic, mean, and diastolic arterial pressure using the oscillometric method; electrocardiogram; rectal temperature; partial pressure of CO2 at the end of expiration: and partial saturation of O2 in hemoglobin were continuously monitored. The evaluation of nociception was based on the changes in the aforementioned physiological parameters. The rate of remifentanil used did not change over time with the use of carprofen. However, animals that received grapiprant required a lower remifentanil dose at 20, 25, and 30 min during the procedure. The female cats that received carprofen showed an increase in mean heart rate at 30 min compared to that at 20 and 25 min. In the Grapiprant group, the heart rate at 35 min was higher only than that observed at 25 min. Discussion: The remifentanil rate did not differ between the groups, even between the times for GCAR. However, the remifentanil rate was lower from 20 min of the procedure for GGRA. This decrease may be related to a decrease in the need for anesthetics and analgesics by decreasing temperature, which causes decreases in metabolism and surgical stimulation. The increase in systolic, mean, diastolic, and heart rate arterial pressure parameters observed in both treatments after 15 min of anesthesia is related to the nociceptive stimulus resulting from traction and ligation of the ovarian pedicles and maneuvers for exteriorization of the uterus. These are considered the moments of greater surgical stimulus during ovariohysterectomy, evidenced by the greater release of cortisol and increase in physiological parameters. The results of this study show that the administration of carprofen or grapiprant was clinically similar when used preemptively for perioperative analgesia in cats submitted to elective ovariohysterectomy.

Anestesia intravenosa parcial (AIVP) em uma lobo-guará (Chrysocyon brachyurus) neonata / Partial intravenous anesthesia (PIVA) in a neonate maned wolf (Chrysocyon brachyurus)

Background: The maned wolf (Chrysocyon brachyurus) is the largest canid in South America and the only representative of its genus. The scientific literature presents studies referring to the management and anaesthesia of the species but is scarce in case of emergency procedures, and to date, there are no reports of anaesthesia for emergency procedures in a neonatal maned wolf. Thus, this study aimed to report xenotransfusion and emergency anaesthesia for thoracic limb amputation in an approximately 8-days-old maned wolf pup. Case: A maned wolf pup, approximately 8-day-old, with a history of an accident with an agricultural machine, was referred to the Veterinary Hospital of the Federal University of Paraná - Palotina Sector (HVP - UFPR) with a grade III open fracture of left radius and ulna. At the physical evaluation, bullous rales were observed in the right caudal lobe on pulmonary auscultation, hypoglycemia and severe dehydration, the latter being determined by the occurrence of enophthalmos, increased capillary refill time and skin turgor (3 s). The hemogram revealed regenerative hypochromic macrocytic anaemia, thrombocytopenia and leukopenia, and the chest radiograph showed alveolar pattern opacification, associated with the presence of air bronchograms in the caudal lobes, more evident on the right side, suggestive of pulmonary contusion. Considering the laboratory alterations and the need for amputation of the thoracic limb, xenotransfusion was chosen before the anaesthetic procedure. The animal was pre-medicated with methadone 0.2 mg/kg and anaesthetic induction was performed with propofol titrated to effect, requiring 10 mg/kg. This was followed by endotracheal intubation and anaesthetic maintenance using the partial intravenous technique with an infusion of 5 µg/kg/h of remifentanil and Isoflurane vaporised through a non-rebreathing system in oxygen at 0.6. Anaesthetic monitoring included heart rate and electrocardiogram tracing, respiratory rate, oxyhemoglobin saturation, end-tidal partial pressure of carbon dioxide, systemic blood pressure by the oscillometric method, and oesophageal body temperature. Although the blood tests after the transfusion showed an increase in hematocrit, changes suggestive of a delayed hemolytic reaction because of the transfusion were also noticed. Discussion: Preanesthetic stabilisation is critical, as anaesthesia of unstable patients may result in a higher risk of anaesthetic complications. Critically ill patients may present systemic imbalances that can trigger pharmacokinetic and pharmacodynamic changes of anaesthetics and analgesics. Neonates have several marked physiological differences, since some organs are still immature, have a high body volume of water, and present a reduced amount of total fat and concentrations of circulating proteins, making it necessary to adjust protocols and doses used for these patients. Blood transfusion between the same species is always the best option, though xenotransfusion becomes an option when there is no homologous donor available. However, it can present a great risk to life, as there is a lack of studies regarding the blood typing of the species and blood compatibility tests. We concluded that there was an increase in hematocrit after 24 h of xenotransfusion and, even with signs of delayed hemolytic reaction observed in the blood test, the patient did not show specific clinical signs of transfusion reaction. The pup was sensitive to methadone but required a high dose of propofol for anaesthetic induction. The use of methadone as a pre-anaesthetic agent and the infusion of remifentanil provided adequate analgesia based on the parameters evaluated.

Multimodal anesthesia associated with regional block in a dog who underwent corrective surgery for persistent right aortic arch: case report / Anestesia multimodal associada a bloqueio loco-regional em cão submetido a cirurgia corretiva para persistência de arco aórtico direito: relato de caso

The persistence of the fourth right aortic arch (PRAA) is a congenital malformation that affects the heart base's main vessels. Surgical treatment is recommended and should be advocated as a matter of urgency. In this context, efficient anesthesia planning is necessary, with satisfactory analgesia, associating multimodal techniques with regional blocks. The present work aims to report the anesthetic procedure during corrective surgery for PRAA in a dog. Neuroleptanalgesia was intramuscularly performed, using acepromazine (0.015 mg.kg-1) and methadone (0.3 mg.kg-1) in pre-anesthetic medication. Ketamine (1 mg.kg-1) and propofol (3 mg.kg-1) were administered at induction, both intravenously, followed by maintenance using total intravenous anesthesia with propofol (initial rate of 0.4 mg.kg-1 .minute) and remifentanil, (0.2 mcg.kg.-1.minute). In addition, ultrasound-guided regional intercostal block was performed, with 5% bupivacaine without vasoconstrictor (0.05ml.kg-1). Ketamine infusion was postoperatively maintained for one hour. The instituted protocol proved to be satisfactory in controlling trans and postoperative pain, maintaining all parameters stable during and after the procedure, without any intercurrence. Thus, the protocol provided quality recovery to the patient.(AU)

A persistência do quarto arco aórtico direito é uma má formação congênita, afetando os principais vasos da base cardíaca. O tratamento cirúrgico é recomendado e preconiza-se um planejamento anestésico eficiente, associando-se técnicas multimodais a bloqueios regionais. O presente trabalho objetiva relatar a anestesia durante cirurgia corretiva de PDA em cão. Na medicação pré-anestésica, instituiu-se neuroleptonalgesia, utilizando-se acepromazina (0,015 mg.kg-1) e metadona (0,3 mg.kg-1), por via intramuscular. Na indução, foi administrada cetamina (1mg.kg -1) e propofol (3 mg.kg-1). Para manutenção, utilizou--se propofol (taxa inicial de 0,4 mg.kg-1.minuto) e remifentanil, (0,2 mcg.kg-1.minuto). Além disso, foi realizado bloqueio regional intercostal guiado por ultrassom com bupivacaína sem vasoconstritor a 5% (0,05ml.kg-1). O paciente permaneceu em infusão analgésica de cetamina por uma hora, no pós operatório. O protocolo estabelecido demonstrou ser satisfatório no controle de dor trans e pós-operatória, mantendo todos os parâmetros estáveis, sem nenhuma intercorrência, proporcionando qualidade de recuperação ao paciente.(AU)

Anestesia para correção de shunt portossistêmico com anel de ameróide em cão / Anesthesia for the correction of portosystemic shunt with an ameroid ring in a dog

O shunt ou desvio portossistêmico (DPS) é uma conexão anormal entre a circulação portal e sistêmica, que desvia o fluxo sanguíneo do fígado em variados graus. Nesse contexto, uma anestesia de qualidade e segura faz toda diferença na recuperação do paciente. Com isso, o presente trabalho teve o objetivo de relatar a técnica anestésica utilizada para o tratamento cirúrgico de um caso de shunt portossistêmico congênito em um cão da raça Yorkshire Terrier, fêmea, de quatro anos, pesando aproximadamente quatro quilos, que apresentava sintomas neurológicos decorrentes de encefalopatia hepática, devido à DPS. Para a medicação pré-anestésica (MPA), foi utilizado o cloridrato de remifentanila (2mg), na taxa de 10µg/Kg/h. Propofol (1%) foi utilizado para indução anestésica, na dose de 1mg/Kg/min, e para anestesia periglótica foi usado cloridrato de lidocaína (2%), no volume de 0,1mL/Kg. Quanto à manutenção anestésica, foi utilizado isoflurano (100%), em um vaporizador universal, citrato de maropitant (1%) em infusão contínua, na taxa de 30µg/Kg/h, cloridrato de remifentanila (2%), na mesma taxa utilizada na MPA, cetamina (10%), na taxa de 0,6mg/Kg/h, e brometo de rocurônio (10mg/mL), na dose de 0,15mg/Kg. Antes do início da cirurgia, foi realizado um bloqueio intraperitoneal com cloridrato de ropivacaína (0,4mg/Kg) diluída em 0,4mL/Kg, na dose de 0,1mL/Kg. Durante todo o procedimento cirúrgico, não houveram intercorrências nem alterações nos parâmetros fisiológicos. Dessa forma, pôde-se observar a eficácia da técnica anestésica utilizada para correção de shunt portossistêmico em um cão apresentando sintomatologia neurológica.

Shunt or portosystemic deviation (DPS) is an abnormal connection between portal and systemic circulation that diverts blood flow from the liver to varying degrees. In this context, quality and safe anesthesia makes all the difference in the patient's recovery. Thus, the present study aims to report the anesthetic technique used for the surgical treatment of a case of congenital portosystemic shunt in a four-year-old Yorkshire Terrier dog, weighing approximately four kilograms, which presented neurological symptoms resulting from of hepatic encephalopathy due to DPS. For pre-anesthetic medication (MPA), remifentanil hydrochloride (2mg) was used at a rate of 10µg/Kg/h. Propofol (1%) was used for anesthetic induction at a dose of 1mg/kg/min and for periglotic anesthesia lidocaine hydrochloride (2%) in a volume of 0.1mL/kg was used. As for anesthetic maintenance, isoflurane (100%) in a universal vaporizer, maropitant citrate (1%) in continuous infusion, at the rate of 30µg/Kg/h, remifentanil hydrochloride (2%), at the same rate used in MPA, ketamine (10%) at a rate of 0.6mg/kg/h and rocuronium bromide (10mg/mL), at a dose of 0.15mg/kg. Before the start of surgery, an intraperitoneal block was performed with ropivacaine hydrochloride (0.4mg/kg) diluted in 0.4mL/kg, in the dose of 0.1mL/kg. Throughout the surgical procedure, there were no complications or changes in physiological parameters. Thus, it was possible to observe the effectiveness of the anesthetic technique used to correct portosystemic shunt in a dog presenting neurological symptoms.

Anestesia para correção de shunt portossistêmico com anel de ameróide em cão / Anesthesia for the correction of portosystemic shunt with an ameroid ring in a dog

O shunt ou desvio portossistêmico (DPS) é uma conexão anormal entre a circulação portal e sistêmica, que desvia o fluxo sanguíneo do fígado em variados graus. Nesse contexto, uma anestesia de qualidade e segura faz toda diferença na recuperação do paciente. Com isso, o presente trabalho teve o objetivo de relatar a técnica anestésica utilizada para o tratamento cirúrgico de um caso de shunt portossistêmico congênito em um cão da raça Yorkshire Terrier, fêmea, de quatro anos, pesando aproximadamente quatro quilos, que apresentava sintomas neurológicos decorrentes de encefalopatia hepática, devido à DPS. Para a medicação pré-anestésica (MPA), foi utilizado o cloridrato de remifentanila (2mg), na taxa de 10µg/Kg/h. Propofol (1%) foi utilizado para indução anestésica, na dose de 1mg/Kg/min, e para anestesia periglótica foi usado cloridrato de lidocaína (2%), no volume de 0,1mL/Kg. Quanto à manutenção anestésica, foi utilizado isoflurano (100%), em um vaporizador universal, citrato de maropitant (1%) em infusão contínua, na taxa de 30µg/Kg/h, cloridrato de remifentanila (2%), na mesma taxa utilizada na MPA, cetamina (10%), na taxa de 0,6mg/Kg/h, e brometo de rocurônio (10mg/mL), na dose de 0,15mg/Kg. Antes do início da cirurgia, foi realizado um bloqueio intraperitoneal com cloridrato de ropivacaína (0,4mg/Kg) diluída em 0,4mL/Kg, na dose de 0,1mL/Kg. Durante todo o procedimento cirúrgico, não houveram intercorrências nem alterações nos parâmetros fisiológicos. Dessa forma, pôde-se observar a eficácia da técnica anestésica utilizada para correção de shunt portossistêmico em um cão apresentando sintomatologia neurológica.(AU)

Shunt or portosystemic deviation (DPS) is an abnormal connection between portal and systemic circulation that diverts blood flow from the liver to varying degrees. In this context, quality and safe anesthesia makes all the difference in the patient's recovery. Thus, the present study aims to report the anesthetic technique used for the surgical treatment of a case of congenital portosystemic shunt in a four-year-old Yorkshire Terrier dog, weighing approximately four kilograms, which presented neurological symptoms resulting from of hepatic encephalopathy due to DPS. For pre-anesthetic medication (MPA), remifentanil hydrochloride (2mg) was used at a rate of 10µg/Kg/h. Propofol (1%) was used for anesthetic induction at a dose of 1mg/kg/min and for periglotic anesthesia lidocaine hydrochloride (2%) in a volume of 0.1mL/kg was used. As for anesthetic maintenance, isoflurane (100%) in a universal vaporizer, maropitant citrate (1%) in continuous infusion, at the rate of 30µg/Kg/h, remifentanil hydrochloride (2%), at the same rate used in MPA, ketamine (10%) at a rate of 0.6mg/kg/h and rocuronium bromide (10mg/mL), at a dose of 0.15mg/kg. Before the start of surgery, an intraperitoneal block was performed with ropivacaine hydrochloride (0.4mg/kg) diluted in 0.4mL/kg, in the dose of 0.1mL/kg. Throughout the surgical procedure, there were no complications or changes in physiological parameters. Thus, it was possible to observe the effectiveness of the anesthetic technique used to correct portosystemic shunt in a dog presenting neurological symptoms.(AU)

Utilização de anestesia total intravenosa em felino submetido a oóforosalpingohisterectomia / Use of total intravenous anesthesia in feliÍe submitted to oophoosalpingohisterectomomy

O presente estudo objetivou analisar um protocolo de anestesia intravenosa total para a realização de ovariosalpingohisterectomia em gato doméstico (Felis catus), fêmea, sem raça definida, com idade de 2 anos e pesando 3,425 kg. A medicação pré-anestésica foi realizada com maropitant (1mg/kg), metadona (0,3mg/kg), midazolam (0,3mg/kg) e dexmedetomidina (3mcg/kg), na indução foi utilizado propofol (4mg/kg). Na manutenção utilizou-se propofol (0,15mg/kg/h) e remifentanila (0,15µg/kg/min), ambos em infusão contínua. Como parâmetros, foram mensurados e avaliados eletrocardiograma, frequência cardíaca e respiratória, onda pletismográfica de pulso, oximetria, capnografia, temperatura, pressão arterial não invasiva sistólica, diastólica e média. Ademais, também foram avaliados o grau de sedação, qualidade da indução anestésica, tempo de recuperação e dor pós-operatória. A paciente apresentou grau de sedação satisfatório após a medicação préanestésica. Durante o período trans-anestésico observou-se constância no plano anestésico, alto grau de analgesia e relaxamento suficiente, além de estabilidade cardiovascular e hemodinâmica, permitindo a realização do procedimento cirúrgico sem intercorrências. A remifentanila promoveu intensa analgesia, permitindo que velocidade de infusão do propofol permanecesse na dose de 0,15mg/kg/h durante toda a manutenção anestésica. A infusão de cloridrato de remifentanila associado ao propofol provocou depressão respiratória, porém os demais parâmetros mostraram-se dentro dos padrões sugeridos para a espécie felina. No pós-operatório não houve complicações e a paciente apresentou tempo de recuperação rápido. O grau de dor pós-operatória observado foi considerado leve (3,3%). Sendo assim o protocolo empregado neste estudo foi seguro, visto as mínimas alterações fisiológicas que provocou, além de adequado para o procedimento de OSH em gatos.

The present study aimed to analyze a protocol of total intravenous anesthesia for the performance of ovariosalpingohisterectomy in domestic cat (Felis catus), female, mixed breed, aged 2 years and weighing 3.425 kg. Pre-anesthetic medication was performed with maropitant (1mg/kg), methadone (0.3mg/kg), midazolam (0.3mg/kg) and dexmedetomidine (3mcg/kg), propofol (4mg/kg) was used for induction. For maintenance, propofol (0.15mg/kg/h) and remifentanil (0.15µg/kg/min) were used, both in continuous infusion. As parameters, electrocardiogram, heart and respiratory rate, pulse plethysmography wave, oximetry, capnography, temperature, non-invasive systolic, diastolic and mean blood pressure were measured and evaluated. In addition, the degree of sedation, quality of anesthetic induction, recovery time and postoperative pain were also evaluated. The patient had a satisfactory level of sedation . During the trans-anesthetic period, constancy was observed in the anesthetic plan, a high degree of analgesia and sufficient relaxation, in addition to cardiovascular and hemodynamic stability, allowing the surgical procedure to be performed without complications. Remifentanil promoted intense analgesia, allowing the propofol infusion rate to remain at a dose of 0.15mg/kg/h throughout the anesthetic maintenance. The infusion of remifentanil hydrochloride associated with propofol caused respiratory depression, but the other parameters were within the standards suggested for the feline species. In the postoperative period there were no complications and the patient had a quick recovery time. The degree of postoperative pain observed was considered mild (3.3%). Thus, the protocol used in this study was safe, given the minimal physiological changes it caused, in addition to being suitable for the OSH procedure in cats.

Utilização de anestesia total intravenosa em felino submetido a oóforosalpingohisterectomia / Use of total intravenous anesthesia in feliÍe submitted to oophoosalpingohisterectomomy

O presente estudo objetivou analisar um protocolo de anestesia intravenosa total para a realização de ovariosalpingohisterectomia em gato doméstico (Felis catus), fêmea, sem raça definida, com idade de 2 anos e pesando 3,425 kg. A medicação pré-anestésica foi realizada com maropitant (1mg/kg), metadona (0,3mg/kg), midazolam (0,3mg/kg) e dexmedetomidina (3mcg/kg), na indução foi utilizado propofol (4mg/kg). Na manutenção utilizou-se propofol (0,15mg/kg/h) e remifentanila (0,15µg/kg/min), ambos em infusão contínua. Como parâmetros, foram mensurados e avaliados eletrocardiograma, frequência cardíaca e respiratória, onda pletismográfica de pulso, oximetria, capnografia, temperatura, pressão arterial não invasiva sistólica, diastólica e média. Ademais, também foram avaliados o grau de sedação, qualidade da indução anestésica, tempo de recuperação e dor pós-operatória. A paciente apresentou grau de sedação satisfatório após a medicação préanestésica. Durante o período trans-anestésico observou-se constância no plano anestésico, alto grau de analgesia e relaxamento suficiente, além de estabilidade cardiovascular e hemodinâmica, permitindo a realização do procedimento cirúrgico sem intercorrências. A remifentanila promoveu intensa analgesia, permitindo que velocidade de infusão do propofol permanecesse na dose de 0,15mg/kg/h durante toda a manutenção anestésica. A infusão de cloridrato de remifentanila associado ao propofol provocou depressão respiratória, porém os demais parâmetros mostraram-se dentro dos padrões sugeridos para a espécie felina. No pós-operatório não houve complicações e a paciente apresentou tempo de recuperação rápido. O grau de dor pós-operatória observado foi considerado leve (3,3%). Sendo assim o protocolo empregado neste estudo foi seguro, visto as mínimas alterações fisiológicas que provocou, além de adequado para o procedimento de OSH em gatos.(AU)

The present study aimed to analyze a protocol of total intravenous anesthesia for the performance of ovariosalpingohisterectomy in domestic cat (Felis catus), female, mixed breed, aged 2 years and weighing 3.425 kg. Pre-anesthetic medication was performed with maropitant (1mg/kg), methadone (0.3mg/kg), midazolam (0.3mg/kg) and dexmedetomidine (3mcg/kg), propofol (4mg/kg) was used for induction. For maintenance, propofol (0.15mg/kg/h) and remifentanil (0.15µg/kg/min) were used, both in continuous infusion. As parameters, electrocardiogram, heart and respiratory rate, pulse plethysmography wave, oximetry, capnography, temperature, non-invasive systolic, diastolic and mean blood pressure were measured and evaluated. In addition, the degree of sedation, quality of anesthetic induction, recovery time and postoperative pain were also evaluated. The patient had a satisfactory level of sedation . During the trans-anesthetic period, constancy was observed in the anesthetic plan, a high degree of analgesia and sufficient relaxation, in addition to cardiovascular and hemodynamic stability, allowing the surgical procedure to be performed without complications. Remifentanil promoted intense analgesia, allowing the propofol infusion rate to remain at a dose of 0.15mg/kg/h throughout the anesthetic maintenance. The infusion of remifentanil hydrochloride associated with propofol caused respiratory depression, but the other parameters were within the standards suggested for the feline species. In the postoperative period there were no complications and the patient had a quick recovery time. The degree of postoperative pain observed was considered mild (3.3%). Thus, the protocol used in this study was safe, given the minimal physiological changes it caused, in addition to being suitable for the OSH procedure in cats.(AU)

Randomized, double-blind, placebo-controlled study of the analgesic effect of intraoperative esmolol for laparoscopic gastroplasty

Purpose To evaluate the analgesic effect of esmolol in patients submitted to laparoscopic gastroplasty. Methods Forty patients aged between 18 and 50 years with American Society of Anesthesiologists (ASA) physical status scores of II and III who underwent gastric bypass were allocated to two groups. Group 1 patients received a 0.5-mg/kg bolus of esmolol in 30 mL of saline before induction of anesthesia, followed by an infusion at 15 µg/kg/min until the end of surgery. Group 2 patients received 30 mL of saline as a bolus and then an infusion of saline. Anesthesia included fentanyl (3 µg/kg), propofol (2-4 mg/kg), rocuronium (0.6 mg/kg), and 2% sevoflurane, with remifentanil if necessary. The following parameters were evaluated: pain intensity over 24h, remifentanil consumption, the first analgesic request, morphine consumption, and side effects. Results Pain intensity was lower in the esmolol group except at T0 (after extubation) and 12h postoperatively. Remifentanil supplementation, recovery time, and postoperative morphine supplementation were lower in the esmolol group. No differences in the time to the first analgesic request or side effects were found between the groups. Conclusion Intraoperative esmolol promotes reductions in pain intensity and the need for analgesic supplementation without adverse effects, thus representing an effective drug for multimodal analgesia in gastroplasty.(AU)

Early postoperative recovery after intracranial surgical procedures. Comparison of the effects of sevoflurane and desflurane

PURPOSE: To compared the effects of sevoflurane and desflurane on early anesthesia recovery in patients undergoing to craniotomy for intracranial lesions. METHODS: After IRB approval, the study included 50 patients aged 18-70 years who had ASA physical statuses of I-II and were scheduled for intracranial surgery. Patients were randomly divided into two groups: sevoflurane and desflurane. Anaesthesia was routinely induced in all patients followed by desflurane 5%-6% or sevoflurane 1%-2%. Moreover remifentanil infusion (0.05-0.2 mcg/kg/min) was adjusted to maintain mean arterial pressure (MAP) within 20% baseline and heart rate 90 bpm. Postoperatively, patients were evaluated over time for responses to painful stimulus, eye opening, hand squeezing, extubation, orientation and time required to achieve a Modified Aldrete Score of 9-10. Parametric and non-parametric data were assessed using Student's t- and Mann-Whitney U tests, respectively. A p 0.05 was taken as statistically significant. RESULTS: The times to responses to painful stimuli (7.7±2.7 vs. 4.8±1.7 min.; p 0.001), emergence (9.5±2.81 vs. 6.3±2.2 min.; p 0.001), hand-squeezing (12.1±2.9 vs. 8.2±2.3 min.; p 0.001), extubation (10.1±2.87 vs. 7.1±1.6 min.; p 0.001), orientation (15.3±3.2 vs. 10.3±2.7 min.; p 0.001) and Aldrete score of 9-10 (23.3±6.1 vs. 15.8±3.8 min.; p 0.001) were significantly lower with desflurane-based anaesthesia vs. sevoflurane-based anaesthesia. CONCLUSION: Desflurane yields early recovery functions and facilitates early postoperative neurologic examinations of intracranial surgery patients.(AU)

Remifentanil protects uterus against ischemia-reperfusion injury in rats

To investigate the effects of remifentanil as an antioxidant and analyze the histopathologic, biochemical changes in experimental ischemia-reperfusion (I/R) exposed rat uteri. METHODS: Wistar albino rats were assigned to three groups (n = 7). 2h period of ischemia was followed by 1h of reperfusion in the I/R and the I/R-remifentanil groups. After ischemia, no drug was administered in the sham and I/R groups. In the I/R-remifentanil group, remifentanil infusion (2 g/kg/min) was started in the ischemia period, and continued until the end of reperfusion. After the ischemic and reperfusion period, the ischemic uterine horns were removed surgically for biochemical and histopathologic examination. Tissue damage scores (endometrial epithelial glandular leukocytosis, degeneration, and endometrial stromal changes) were examined. Malondialdehyde levels and catalase, superoxide dismutase enzyme activities in tissue were measured. RESULTS: We found significantly lower epithelial leukocytosis and cell degeneration in the I/R-remifentanil group (p 0.05). Remifentanil administration significantly decreased concentrations of malondialdehyde, and increased catalase and superoxide dismutase enzyme activities (p 0.05). CONCLUSION: Remifentanil appears to protect the uterine tissue against ischemia-reperfusion and can be used safely in uterus transplantation.(AU)

Evaluation of the isoflurane-sparing effects of a constant rate infusion of remifentanil undergoing mastectomy in dogs / Avaliação da concentração expirada de isoflurano em infusão continua de remifentanil em cadelas submetidas a mastectomia

Os objetivos deste estudo são a avaliação dos efeitos de duas taxas fixas de infusão continua de remifentanil na concentração expirada de isoflurano (ETiso) em cadelas submetidas à mastectomia. Foram utilizadas 18 cadelas, 12+2 anos de idade e pesando 15+5 Kg. Os animais foram distribuídos aleatoriamente em 3 grupos (n=6/grupo) e submetidos à mastectomia unilateral devido a neoplasia mamária. Todos os animais foram pré-medicados com morfina (0,5 mg Kg-1) e acepromazina (0,03 mg Kg-1), ambas por via intramuscular (IM). A indução da anestesia foi realizada com propofol (dose-efeito). Os animais foram intubados e conectados a um sistema circular com reinalação de gases. Foi utilizada ventilação com pressão positiva intermitente para manutenção de normocapnia com fluxo de oxigênio de 2 L/min e FiO2 de 100%. A anestesia foi mantida com isoflurano e solução salina (grupo controle [GCON], n=6) ou infusão intravenosa de remifentanil na taxa de 0,15 ?g Kg-1min-1 (REMI 0,15 n=6) ou 0,3 ?g Kg-1min-1 (REMI 0,3 n=6). As variáveis cardiovasculares e a ETiso foram monitoradas antes e a cada 15 minutos após o início da cirurgia. Os dados foram analisados por ANOVA com repetições múltiplas para comparações entre momentos e ANOVA seguida de teste Student Newman Keuls (p£0.05) para comparações entre grupos. A frequência cardíaca foi menor em todos os momentos nos grupos REMI 0,15 e REMI 0,3 em comparação com GCON, sendo que não foram encontradas diferenças estatísticas para essa variável entre os dois grupos com infusão de remifentanil. Adicionalmente, os valores de pressão arterial (PAS, PAM e PAD) não apresentaram diferenças entre grupos. Os valores basais (antes da cirurgia) de ETiso não apresentaram diferenças entre os 3 grupos. Após o início da cirurgia, a ETiso variou entre 1,37±0,3 e 1,05±0,19 no grupo controle; nos grupos REMI 0,15 e REMI 0,3 a ETiso foi 36,5% e 65,7% menor que no grupo controle (M15).[...](AU)

The aims of this study were to evaluate the effects of two constant rate infusions of remifentanil on end tidal isoflurane (ETiso) in dogs undergoing mastectomy surgery. Eighteen bitches, 12+2 years of age, weighing 15+5 Kg were randomized into 3 groups (n=6/group) and underwent unilateral mastectomy due to mammary neoplasia. All animals received the premedications of morphine (0.5 mg Kg-1) and acepromazine (0.03 mg Kg-1) by intramuscular route (IM). Propofol dose-effect was used for induction of anesthesia. The animals were intubated and connected to a circle breathing system, and IPPV (intermittent positive pressure ventilation) was used to maintain normocapnia with an oxygen flow rate of 2 L/min and FiO2 100%. Anesthesia was maintained with isoflurane and saline solution (control group [GCON], n=6) or intravenous infusion of remifentanil at a rate of 0.15 ?g Kg-1min-1 (REMI 0.15 n=6) or 0.3 ?g Kg-1min-1 (REMI 0.3 n=6). Cardiopulmonary variables and ETiso were monitored before and every 15 minutes after the start of surgery. The data were analyzed by ANOVA with multiple repetitions between moments and ANOVA followed by the Student Newman Keuls test (p£0.05) for comparisons between groups. Heart rate was lower at all moments in the REMI 0.15 and REMI 0.3 groups than in the GCON, and heart rate was not significantly different between the two remifentanil infusion groups. Additionally, the arterial blood pressure values (SAP, MAP and DAP) were not different between all groups. Baseline values (before surgery) of ETiso were not different between the 3 groups. After the start of surgery, ETiso ranged from 1.37±0.3 to 1.05±0.19 in the control group; in the REMI 0.15 and REMI 0.3 groups, ETiso was 36.5% and 65.7% lower than in the control group (M15). Remifentanil infusion reduced ETiso in a dose-dependent manner in animals undergoing radical mastectomy without causing significant cardiopulmonary alterations.(AU)

Avaliação da manobra de recrutamento alveolar por escalonamento da PEEP por meio da técnica de tomografia computadorizada em cães submetidos à anestesia intravenosa total

A atelectasia pulmonar é um evento comum que ocorre durante a anestesia. A ventilação mecânica (VM) é indicada nestes casos para reverter o quadro garantindo trocas gasosas adequadas e melhora da oxigenação. Apenas a instituição da VM não é suficiente para realizar a abertura destes alvéolos, sendo necessário a associação de manobras de recrutamento alveolar (MRA). As MRA não são isentas de riscos e podem promover hipersdistensão de algumas áreas do pulmão, com intuito de visualizar tais alterações e minimizá-las, técnicas de imagens são utilizadas, como a tomografia computadorizada. Este estudo avaliou a MRA por escalonamento de PEEP, oxigenação e troca gasosa de 12 cães jovens, pesando acima de 15 kg, com idade entre 1 a 5 anos, de ambos os sexos e de diferentes raças, submetidos a castração eletiva. Para tanto foram avaliados parâmetros cardiovasculares, de oxigenação, aeração pulmonar, mecânica ventilatória e imagens de tomografia computadorizada (TC). Os animais receberam acepromazina (0,03 mg/kg) e meperidina (3 mg/kg) por via IM como medicação pré-anestésica. A indução anestésica foi realizada com propofol (5 mg/kg) e mantida com a infusão do mesmo (0,2 0,4 mg/kg/min) associado ao remifentanil (0,1 a 0,4 mcg/kg/min) e rocurônio (bolus 0,6 mg/kg, seguido de infusão contínua 1 mg/kg/h). Inicialmente os animais foram ventilados no modo volume controlado de 7 mL/kg, PEEP 0 cmH2O e FiO2 de 100% durante os primeiros 30 min de anestesia. Em seguida, iniciou-se a MRA por escalonamento da PEEP (5, 10, 15, 20 cmH2O ascendente e 15, 10, 5 cmH2O descendente), em todos os momentos se fez a aquisição das imagens de tomografia computadorizada (TC), como também dos demais parâmetros. Foi possível observar melhora na complacência estática (Cstat) e no shunt pulmonar ao fim da MRA. A TC foi capaz de demonstrar que a MRA melhorou a aeração em todo o pulmão, inclusive nas regioes dependentes (centro-dorsal e dorsal). Foi observado aumento do volume de gás e redução da atenuação com o aumento da PEEP e redução do volume e aumento da atenuação com sua diminuição. Contudo ao chegar em PEEP 5d cmH2O, o volume foi significativamente maior que em PEEP 0 cmH2O e a atenuação menor. Portanto a TC permitiu adequada avaliação da MRA a partir de dados de volume e atenuação pulmonar nas imagens e ainda evidenciando ausência de hiperaeração pulmonar ao longo da mesma.

Pulmonary atelectasis is a common event that occurs during anesthesia. Mechanical ventilation (MV) is indicated to reverse this condition, ensuring adequate gas exchange and improved oxygenation. However, simply instituting MV is not sufficient to open the alveoli, as it requires the combination with alveolar recruitment maneuvers (ARM). ARMs are not exempt from risks and can lead to overdistension of some areas of the lung. In order to visualize such alterations and minimize them, imaging techniques can be used, such as computed tomography. The present study evaluated a PEEP titration ARM, oxygenation and gas exchange in 12 young dogs, weighing over 15 kg, aged between 1 and 5 years olds, of both sexes and various breeds, submitted to elective ovariohysterectomy or orchiectomy. Therefore, cardiovascular parameters, oxygenation, pulmonary aeration, ventilatory mechanics and computed tomography (CT) images were evaluated. The animals received acepromazine (0.03 mg/kg) and meperidine (3 mg/kg) intramuscularly as premedication. Anesthesia was induced with propofol (5 mg/kg) and maintained with constant rate infusions of propofol (0.2 - 0.4 mg / kg / min), remifentanil (0.1 to 0.4 mcg / kg / min ) and rocuronium (bolus of 0.6 mg / kg, followed by 1 mg / kg / h). Initially, the animals underwent volume-controlled ventilation with tidal volume of 7 mL / kg, PEEP 0 cmH2O and 100% FiO2 for 30 minutes. Afterwards, the ARM was performed with PEEP titration (sequentially ascending PEEP of 5, 10, 15 and 20 cmH2O, and then descending from 20 to 15, 10 and 5 cmH2O). In all these times points, CT images were acquired, as were the other parameters. An improvement in static compliance (Cstat) and pulmonary shunts was observed by the end of the ARM. CT demonstrated that the ARM enhanced aeration throughout the lungs, including the dependent areas (central-dorsal and dorsal). An increase in gas volume and a decrease in attenuation was observed with PEEP increase, likewise gas volume reduced and attenuation augmented with PEEP decrease. However, when PEEP 5d (descending) cmH2O was reached, gas volume was significantly greater than that it was with PEEP 0 cmH2O, and the attenuation was lower. Therefore, CT allowed an adequate assessment of ARM based on pulmonary volume and attenuation data, and also evidenced the absence of pulmonary hypereraeration throughout the maneuver.

Avaliação das funções sistólica e diastólica através da ecocardiografia transesofágica em cadelas submetidas à anestesia geral inalatória associada à infusão contínua de remifentanil em cirurgias de ovariectomia.

O objetivo desde estudo foi investigar os efeitos do remifentanil nas variáveis de função sistólica e diastólica através da ecocardiografia transesofágica, em cadelas hígidas. Foram empregados 17 animais com peso entre 5 e 30kg para cirurgia de ovariectomia, pré-medicadas com acepromazina 0,03mg/kg associada ao cloridrato de petidina 2mg/kg pela via intramuscular, indução realizada com propofol na dose de 3 a 5mg/kg e manutenção com isoflurano (fração expirada de 1.2%). Durante a anestesia as pacientes foram mantidas com oxigênio (FiO2 60%) (100ml/kg/min), também administrado rocurônio na dose 0,6mg/kg intravenoso e instituída a ventilação controlada por pressão controlada, com os parâmetros ventilatórios de pressão de pico 10 cmH2O, relação inspiração/expiração de 1:2, pressão expiratória final positiva (PEEP) de 3 cmH2O e frequência respiratória ajustada conforme os valores expiratórios de CO2 (ETCO2) 3545mmHg. Em todos pacientes foi realizado bloqueio locorregional do plano transverso do abdome com bupivacaína e iniciado infusão contínua de remifentanil na taxa de infusão de 0,2 ug/kg/min, que se perdurou até final do procedimento. O exame ecocardiográfico transesofágico foi realizado em sete momentos distintos Tbasal (antes do início da infusão contínua de remifentanil), e todos os outros tempos sob infusão do opiode (T0, T5, T15, T30, T45 e T60). Os parâmetros avaliados foram fração de ejeção (FE) do ventrículo esquerdo pelo método de Simpson modificado, a integral velocidade tempo (VTI), volume sistólico (VS), débito cardíaco (DC), bem como a velocidade onda E, velocidade onda A, relação E/A, tempo de desaceleração da onda E, velocidade da onda e parietal, relação E/e parietal. Após análise estatística descritiva baseada na distribuição e nos intervalos de confiança das médias, os resultados do estudo demonstraram que não houve diferença estatística entre os momentos onde paciente estava sob influência do fármaco e o momento basal, para todos parâmetros avaliados. Apesar de observarmos efeitos consideráveis nos parâmetros estudados, quando sob infusão do opioide. Portanto, podemos inferir que o remifentanil demonstrou segurança e estabilidade cardiovascular na amostra estudada, para a taxa de infusão utilizada.

This study is aimed at the investigation of the effects of remifentanil on systolic and diastolic function variables through transesophageal echocardiography in healthy female dogs. Seventeen animals weighing between 5 and 30kg were used for ovariectomy surgery, premedicated with 0.03mg/kg acepromazine associated with 2mg/kg pethidine hydrochloride intramuscularly, induction performed with propofol at a dose of 3 to 5mg/kg and maintenance with isoflurane (1.2% of expired fraction). During anesthesia the patients were maintained with oxygen (FiO2 60%) (100ml / kg / min); 0.6 mg / kg intravenous rocuronium was also administered as well as controlled pressure-controlled ventilation with 10 cmH2O peak pressure ventilatory parameters, 1: 2 inhalation/expiration ratio, 3 cmH2O positive end-expiratory pressure (PEEP), and respiratory rate adjusted according to CO2 (ETCO2) 3545mmHg expiratory values. Locoregional blockade of the transverse abdomen with bupivacaine was performed in all patients and continuous remifentanil infusion started at a rate of 0.2 µg / kg / min, which lasted until the end of the procedure. Transesophageal echocardiographic examination was performed at seven different Tbasal moments (before continuous remifentanil infusion began), and all other times under opioid infusion (T0, T5, T15, T30, T45 and T60). The parameters assessed were: Left ventricular ejection fraction (EF) by the modified Simpson method, velocity time integral (VTI), systolic volume (SV), cardiac output (DC), as well as E wave velocity, A wave velocity, E/A ratio, E wave deceleration time, parietal e wave velocity and parietal E/e ratio. Although considerable effects on the studied parameters were observed when under opioid infusion, following descriptive statistical analysis based on the distribution and confidence intervals of the means, study results showed that there was no statistical difference between the moments where the patient was under the influence of the drug and the basal moment for all parameters assessed. Therefore, the inference being that remifentanil has demonstrated cardiovascular safety and stability in the sample studied for the infusion rate used.

Anestesia total intravenosa em cadelas: avaliação de variáveis cardiovasculares e do requerimento anestésico do propofol utilizado na associação de remifentanil e dexmedetomidina

O remifentanil é um opioide agonista de ação ultracurta com propriedades anestésicas e analgésicas, sendo um fármaco excelente para infusões contínuas por curtos e longos períodos. A dexmedetomidina é um agonista -2 adrenérgico 1620 vezes mais seletivo para receptores -2, utilizada como sedativo e analgésico em diversos protocolos anestésicos. O remifentanil associado a dexmedetomidina pode reduzir o consumo do propofol para a manutenção do plano anestésico devido aos seus efeitos sedativos e analgésicos sinérgicos. Durante o experimento foram utilizadas 31 cadelas, de 1 a 3 anos, pesando 12,1 ± 3,3kg. Foram divididas em três grupos, sendo REMI (bolus de 5 g-1 kg-1 seguido por infusão contínua por 1 hora de 15 g kg-1 h-1 de remifentanil), DEX (bolus de 2 g-1 kg-1 seguido por infusão contínua por 1 hora de 2 g kg-1 h-1) e REMIDEX (mesmas doses e tempo de infusão dos grupos anteriores). O estímulo elétrico (50 mA) foi aplicado no braço direito e a infusão de propofol era aumentada ou reduzida em 0,1 mg kg-1 min-1 baseado na resposta positiva ou negativa ao estímulo. Os dados foram analisados com o teste de Kruskal-Wallis seguido do teste de Dunn e foram apresentados na forma de mediana, mínimo e máximo. A redução da dose do propofol foi analisada com o teste de ANOVA seguido do teste post-hoc de Tukey. A redução das doses do propofol para o grupo REMI, DEX e REMIDEX foram de 68, 90 e 98%, respectivamente. Houve maior redução do DC e do IC em relação ao valor basal no grupo DEX e REMIDEX (45 e 55%, respectivamente). No pós-operatório somente dois animais do grupo REMI necessitaram de resgate analgésico.

Remifentanil is an ultra short acting -opioid agonist with anesthetic and analgesic properties, being an excellent drug for continuous rate infusions for short and long periods. Dexmedetomidine is an -2 adrenergic agonist 1620 times more selective for alpha1 receptors than alpha2, used as a sedative and analgesic in many anesthetic protocols. Remifentanil associated with dexmedetomidine may reduce the consumption of propofol to maintain the anesthetic plane due to its sedative and synergistic analgesic effects. During the experiment, 31 bitches, 1 to 3 years old, weighing 12.1 ± 3.3 kg were used. They were divided into three groups: REMI (bolus of 5 g-1 kg-1 followed by continuous rate infusion for 1 hour of 15 g kg-1 h-1 of remifentanil), DEX (bolus of 2 g-1 kg-1 followed by continuous rate infusion for 1 hour of 2 g kg-1 h-1) and REMIDEX (same doses and infusion time of the previous groups). The electrical stimulus (50 mA) was applied to the right arm and the propofol infusion rate was increased or reduced by 0.1 mg kg-1 min-1 based on the positive or negative response to the stimulus. Data were analyzed using the Kruskal-Wallis test followed by the Dunn test and were presented as median and range. The reduction of propofol was analyzed with the ANOVA test followed by the post-hoc Tukey's test. There was a reduction of propofol doses in 68, 90 and 98% for the REMI, DEX and REMIDEX groups, respectively. There was a greater reduction in the CO and the CI in relation to the baseline value in the DEX and REMIDEX groups (45 and 55%, respectively). In the postoperative period, only two animals in the REMI group required analgesic rescue.

Comparing the pain of propofol via different combinations of fentanyl, sufentanil or remifentanil in gastrointestinal endoscopy

PURPOSE: To evaluate the pain on injection of propofol via different combinations of fentanyl, sufentanil or remifentanil in gastrointestinal endoscopy. METHODS: Total 439 patients were randomly allocated into 6 groups. Propofol & fentanil (PF) group received 1 μg/kg fentanyl, propofol & sufentanil (PS) group received 0.1 μg/kg sufentanil and propofol & remifentanyl (PR) group received 1 μg/kg remifentanyl prior to administration of 1-2 mg/kg of propofol. The propofol & half-fentanil (Pf) group, propofol & half-sufentanil (Ps) group and propofol & half-remifentanyl (Pr) group were given 0.5 μg/kg fentanyl, 0.05 μg/kg sufentanil and 0.5 μg/kg remifentanyl, respectively and later administrated 1-2 mg/kg propofol. All patients were monitored for the blood pressure (MAP), heart rate (HR), and oxygen saturation (SpO2). Additionally, the pain intensity was assessed using a 4-point verbal rating scale (VRS) by professional doctors. RESULTS: The incidence of pain due to propofol injection in Ps group (33.8%) was significantly lower than other 5 groups. The heart rate (HR) and mean arterial pressure (MAP) were maintained within the normal limits in all six groups and there was no hypotension or bradycardia encountered during the study period. CONCLUSION: Propofol and sufentanil group was the most suitable program for painless gastroscopy. .(AU)

Cardiorespiratory dynamics of sedated pigs submitted to different inspired oxygen fractions under controlled mechanical ventilation

Background: Individuals submitted to situations of deep sedation have a marked decrease in their ventilatory capacity.The provision of adequate ventilation and oxygenation in critically ill patients submitted to sedation in intensive therapyhas been the subject of special care. In such cases, exposure to low inspired oxygen fractions (FIO2) is a factor that caninfl uence alveolar perfusion and respiratory performance. The aim of this study is to evaluate the effects of three inspiredoxygen fractions (80%, 60% or 40%) on the cardiorespiratory dynamics of pigs submitted to mechanical ventilation byintermittent positive pressure in deep sedation with propofol-remifentanil.Material, Methods & Results: Twenty crossbred pigs weighing between 17 and 25 kg and aged between 60 and 90 dayswere used. Each animal was submitted to deep sedation for 2h in randomly assigned FIO2 (80%, 60% or 40%). Scores suchas heart and respiratory rate, blood pressure, respirometry (PaO2, P(A-a)O2, PIP, Vmin), physiological dead space, pulmonaryshunt and blood gas analysis (pH, PaO2, PaCO2, HCO3) were observed, evaluated and compared. Patients were evaluatedafter sedation was induced with propofol (12 mg.kg-1) and remifentanil (1 mcg.kg-1). To maintain the level of sedation weused propofol (an average of 18 mg.kg-1.h-1) and remifentanil (0.5 mcg.kg-1.min-1). Intubation was preceded after the onsetof sedation to mechanical ventilation - volume-cycled, intermittent positive pressure. Patients received a tidal volume of10 mL.kg-1 and an I:E ratio of 1:2, positive end-expiratory pressure of 4 cmH2O with three inspired oxygen fractions. Patients respiratory rate was adjusted so as to maintain end-tidal carbon dioxide pressure between 35 and 45 mmHg. Datawere subjected to analysis of variance for repeated measures followed by a Tukey test. Patients receiving a 40% oxygenconcentration showed an average heart rate higher than the others. Shunt levels...(AU)

Avaliação da eficácia analgésica do bloqueio do plano transverso do abdome, guiado por ultrassom, em cadelas submetidas à ovariectomia eletiva

Na medicina, o bloqueio do plano transverso do abdome (TAP block) mostra-se eficaz em diversos procedimentos cirúrgicos. Desta forma, o presente estudo prospectivo, randomizado e cego teve como objetivo avaliar a eficácia analgésica do TAP block, guiado pela ultrassonografia em cadelas submetidas a ovariectomia. Para tanto, foram utilizados 32 animais distribuídos aleatoriamente em 2 grupos com 16 animais. O grupo TAP block controle (TBC) recebeu água para injeção 0,2 mL/kg/ponto. Já o grupo TAP block bupivacaína (TBB) recebeu bupivacaína 0,2 mL/kg/ponto à 0,25%, ambos os grupos na abordagem dos quatro pontos. Os animais foram pré-medicados com acepromazina (0,03 mg/kg) e meperidina (2 mg/kg) pela via intramuscular, a indução anestésica com propofol (3 a 5 mg/kg) pela via intravenosa e o isofluorano foi empregado para manutenção da anestesia. Ainda, todos os animais no período transoperatório receberam infusão contínua de remifentanil (0,2 ug/kg/min) e rocurônio (0,6 mg/kg), ambos pela via intravenosa. As variáveis mensuradas foram: frequências cardíaca e respiratória, pressão arterial, temperatura, saturação periférica da oxihemoglobina, concentração de dióxido de carbono no ar expirado, concentração de isofluorano no ar expirado, cortisol sérico, analgesia e sedação. As análises estatísticas foram efetuadas com o software GraphPad Prism versão 6.0 e o grau de significância estabelecido para os testes foi de 5% (P < 0,05). Foram analisados parâmetros vitais, grau de analgesia por meio da escala numérica verbal (ENV) e escala composta reduzida de Glasgow (GCMPS-SF), grau de sedação, bem como o cortisol sérico em diferentes tempos. Como principais resultados verificou-se que no período transoperatório não houve diferença significativa entre os grupos. Já no pós-operatório, no grupo TBC, 13 animais do total de 16 animais necessitaram de resgate analgésico ao passo que no grupo TBB apenas 1 animal. Com relação a mensuração do cortisol sérico, o grupo TBC apresentou diferença significativa quando comparado ao tempo basal (TB) na tração do primeiro ovário (P <0,0001), e decorridas 2 horas (P = 0,0441) e 8 horas (P= 0,0384) da extubação. Já no grupo TBB, verificou-se que o cortisol apresentou aumento significativo apenas na tração do primeiro ovário e 2 horas após a extubação (P <0,0001). Sendo assim, a partir dos resultados encontrados conclui-se que o TAP block promove analgesia adequada para o período pós-operatório de cadelas submetidas à ovariectomia, podendo ser uma nova alternativa para proporcionar o controle de dor nesse tipo de procedimento. Entretanto, este bloqueio não foi efetivo para modular a resposta neuroendócrina no transoperatório, tendo-se em vista o incremento dos valores do cortisol observados.

In medicine, TAP block showed as an effective method in several surgical procedures. In this context, this prospective, randomized, blinded study aimed to evaluated the analgesic efficacy of TAP block, guided by ultrasound in bitches submitted to ovariectomy. Therefore, 32 animals randomly assigned in two groups with 16 animals were used. Groups consisted of TAP block control (TBC) which received water injection (0.2mL/kg/point) and TAP block bupivacaine (TBB) which received bupivacaine (0.2mL/kg/point at 0.25%), both groups were submitted to four-point approach. Animals were premedicated with acepromazine (0.03mg/kg) and meperidine (2mg/kg) intramuscularly, propofol were used as anesthetic induction (3 to 5mg/kg) intravenously and isofluorane was used to maintenance. In order to standardize groups, in the intraoperative period the animals received continuous infusion of remifentanil (0.2g/kg/min) and rocuronium (0.6 mg/kg), both intravenously. Variables measured were heart and respiratory rates, blood pressure, temperature, oxyhemoglobin peripheral saturation, exhaled carbon dioxide concentration, exhaled isofluorane concentration, serum cortisol, analgesia and sedation. Statistical analyzes were performed using GraphPad Prism version 6.0 software and significance level established was 5% (P<0.05). Before the preanesthetic medication (TB) and 1,2,4,6 and 8 hours after extubation, pain and sedation were assessment using verbal numeric scale (ENV), Glasgow's reduced composite scale (GCMPS-SF) and sedation scale. Moreover, serum cortisol was measured in different moments. As main results it was observed that in intraoperative period there was no significant difference between groups. After surgery, in TBC group, 13 animals out of 16 animals required analgesic rescue, whereas in TBB group this occurred only in one animal. Regarding the measurement of serum cortisol, the TBC group showed significant difference when compared to the baseline time (TB) in the traction of the first ovary (P<0.0001), 2 hours (P=0.0441) and 8 hours (P=0.0384) after extubation. In TBB group, cortisol showed a significant increase only in the traction of the firsty ovary and 2 hours after extubation (P<0.0001). Thus, after this results, it is concluded that the TAP block promotes adequate analgesia in postoperative period of bitches submitted to ovariectomy, and may be a new alternative to provide pain control in this procedure. However, this block was not effective to modulate the neuroendocrine response in the intraoperative period, given the increase in cortisol values observed.

Cardiorespiratory dynamics of sedated pigs submitted to different inspired oxygen fractions under controlled mechanical ventilation

Background: Individuals submitted to situations of deep sedation have a marked decrease in their ventilatory capacity.The provision of adequate ventilation and oxygenation in critically ill patients submitted to sedation in intensive therapyhas been the subject of special care. In such cases, exposure to low inspired oxygen fractions (FIO2) is a factor that caninfl uence alveolar perfusion and respiratory performance. The aim of this study is to evaluate the effects of three inspiredoxygen fractions (80%, 60% or 40%) on the cardiorespiratory dynamics of pigs submitted to mechanical ventilation byintermittent positive pressure in deep sedation with propofol-remifentanil.Material, Methods & Results: Twenty crossbred pigs weighing between 17 and 25 kg and aged between 60 and 90 dayswere used. Each animal was submitted to deep sedation for 2h in randomly assigned FIO2 (80%, 60% or 40%). Scores suchas heart and respiratory rate, blood pressure, respirometry (PaO2, P(A-a)O2, PIP, Vmin), physiological dead space, pulmonaryshunt and blood gas analysis (pH, PaO2, PaCO2, HCO3) were observed, evaluated and compared. Patients were evaluatedafter sedation was induced with propofol (12 mg.kg-1) and remifentanil (1 mcg.kg-1). To maintain the level of sedation weused propofol (an average of 18 mg.kg-1.h-1) and remifentanil (0.5 mcg.kg-1.min-1). Intubation was preceded after the onsetof sedation to mechanical ventilation - volume-cycled, intermittent positive pressure. Patients received a tidal volume of10 mL.kg-1 and an I:E ratio of 1:2, positive end-expiratory pressure of 4 cmH2O with three inspired oxygen fractions. Patients’ respiratory rate was adjusted so as to maintain end-tidal carbon dioxide pressure between 35 and 45 mmHg. Datawere subjected to analysis of variance for repeated measures followed by a Tukey test. Patients receiving a 40% oxygenconcentration showed an average heart rate higher than the others. Shunt levels...

A infusão contínua de remifentanil não altera a função sistólica e diastólica ventricular esquerda, em cães anestesiados com propofol

Devido às suas caracteristicas farmacológicas atrativas, o remifentanil é muito utilizado na medicina humana para sedação e anestesia de pacientes críticos, principalmente cardiopatas. A maioria dos estudos mostram que este opioide é capaz de promover analgesia satisfatória sem produzir alterações hemodinamicas significativas, preservando a função sistólica e diastólica. Entretanto, outros autores relatam que dependendo da forma como é utilizado, os pacientes podem apresentar diminuição da frequência cardíaca, débito cardíaco e da pressão arterial, resultando em instabilidade hemodinâmica. Na medicina veterinária, há poucos estudos investigando os efeitos cardiovasculares do remifentanil, limitando o seu emprego de maneira mais segura na rotina clínica. Com o aumento da longevidade dos cães, houve um crescimento proporcional do número de pacientes cardiopatas, que necessitam de protocolos anestésicos seguros. Dentro deste cenário, o remifentanil pode se tornar uma excelente opção, caso se demostre seguro do ponto de vista cardiovascular. Até o momento, não há trabalhos utilizando técnicas ecocardiográficas para avaliação da função sistólica e diastólica em cães tratados com remifentanil. Isto posto, com este experimento, objetivou-se avaliar os efeitos da infusão contínua de remifentanil na função sitólica e diastólica do ventrículo esquerdo em cães anestesiados com propofol.

Because of its attractive pharmacological characteristics, remifentanil is widely used in human medicine for sedation and anesthesia in critically ill patients, mainly in cardiovascular diseases. Most studies report that this opioid promotes satisfactory analgesia without significant hemodynamic changes, preserving systolic and diastolic function. However, other authors report that depending on the way it is used, remifentanil administration can decrease heart rate, cardiac output and blood pressure, resulting in hemodynamic instability. In veterinary medicine, there are few studies investigating the cardiovascular effects of remifentanil, limiting its safely in the clinical routine. As the increased longevity of dogs, there was a proportional increase in the number of critically ill patients, including patients with cardiovascular diseases, who required safe anesthetic protocols. Therefore, remifentanil may become an excellent option if it is shown to be safe from a cardiovascular point of view. To date, there are no reports using echocardiographic techniques to assess systolic and diastolic function in dogs treated with remifentanil. The aim of this experiment was to evaluate the effects of continuous infusion of remifentanil on left ventricular systolic and diastolic function in dogs anesthetized with propofol.

Infusão contínua de Propofol e Remifentanil por longo período em gatos

O propofol é um agente anestésico com rápido inicio de ação e curta duração, o que o torna ideal para utilização em protocolos de anestesia intravenosa total. Em gatos, apresenta indução e recuperação anestésicas suave, porém tem uma maior meia-vida de eliminação quando comparado a outras espécies, o que pode tornar a recuperação mais demorada em longos períodos de anestesia. A associação de propofol com opioides diminui sua concentração plasmática necessária para promoção de inconsciência, mantém a estabilidade hemodinâmica e diminui o tempo de recuperação anestésica. O remifentanil destaca-se entre os opioides por apresentar metabolização por esterases inespecíficas presentes no sangue e nos tecidos, facilitando sua eliminação, inclusive no gato. O objetivo deste estudo é avaliar o consumo de propofol, efeitos cardiovasculares, respiratórios e tempo e qualidade da recuperação anestésica em gatos submetidos à infusão de propofol e remifentanil por 150 minutos. Dezesseis gatos adultos receberam dois tratamentos: PRO (n = 8), com indução intravenosa com propofol infundido a 3 mg kg-1 minuto-1 seguido de infusão contínua de propofol em taxa variável iniciando em 0,25 mg kg-1min-1; e PREMI (n = 8), onde o remifentanil foi associado na indução e manutenção com propofol na taxa fixa de 0,25 g kg-1min-1. Foram avaliadas funções cardiovasculares e respiratórias, temperatura, hemogasometria arterial, taxa de infusão do propofol, tempo e qualidade da recuperação anestésica. Dados paramétricos entre grupos foram comparados pelo Teste-t não pareado e entre diferentes momentos da anestesia pela ANOVA e Tukey-Kramer. Escores de recuperação anestésica foram analisados pelo teste Mann-Whitney. Diferenças foram consideradas significativas se p<0,05. A taxa média de propofol infundido foi 40,9% menor no PREMI (0,13 ± 0,07 mg kg-1 minuto-1) em relação ao PRO (0,22 ± 0,05 mg kg-1 minuto-1). A pressão arterial foi mais baixa em PREMI, mas hipotensão não foi observada em nenhum momento. No PREMI ocorreu leve acidose respiratória e hipercapnia. Recuperação anestésica foi significativamente mais curta no PREMI, desde a extubação (9 ± 5 versus 37 ± 26 minutos) até a deambulação normal (88 ± 17 versus 235 ± 50 minutos). Os dois grupos apresentaram excelente qualidade de recuperação. A associação de infusão contínua de remifentanil ao propofol reduz o seu requerimento em mais de 40%, diminuindo o tempo necessário para recuperação anestésica quando utilizado por período prolongado.

Propofol is an anesthetic agent with rapid onset of action and short duration, making it ideal for use in total intravenous anesthesia protocols. In cats, it has mild induction and anesthetic recovery, but has a longer elimination half-life when compared to other species, which can make recovery more time consuming in long periods of anesthesia. The association of propofol with opioids decreases its plasma concentration necessary to promote unconsciousness, maintains hemodynamic stability and decreases anesthetic recovery time. Remifentanil stands out among opioids because it has with metabolism by nonspecific esterases present in blood and other tissues, facilitating its elimination, including in the cat. The objective of this study is to evaluate the consumption of propofol, cardiovascular and respiratory effects and time and quality of anesthetic recovery in cats submitted to infusion of propofol and remifentanil for 150 minutes. Sixteen adult cats received two treatments: PRO (n = 8), with intravenous induction with propofol infused at 3 mg kg-1minute-1 followed by continuous infusion of variable rate propofol starting at 0.25 mg kg-1min-1; and PREMI (n = 8), where remifentanil was associated with induction and maintenance with propofol at the fixed rate of 0.25 g kg-1 min-1. Cardiovascular and respiratory functions, temperature, arterial hemogasometry, propofol infusion rate, time and quality of anesthetic recovery were evaluated. Parametric data between groups were compared by the unpaired t-test and between different moments of anesthesia by ANOVA and Tukey-Kramer. Anesthetic recovery scores were analyzed using the Mann-Whitney test. Differences were considered significant if p <0.05. The mean rate of infused propofol was 40.9% lower in the PREMI (0.13 ± 0.07 mg kg-1min-1) than in the PRO (0,22 ± 0,05 mg kg-1min-1) . Blood pressure was lower in PREMI, but hypotension was not observed at any time. In the PREMI there was mild respiratory acidosis and hypercapnia. Anesthetic recovery was significantly shorter in the PREMI from extubation (9 ± 5 versus 37 ± 26 minutes) until normal ambulation (88 ± 17 versus 235 ± 50 minutes). Both groups presented excellent recovery quality. The association of continuous infusion of remifentanil to propofol reduces its requirement by more than 40%, reducing the time required for anesthesia recovery when used for an extended period.