Bezold-Jarisch reflex induced by dopamine during isoflurane anesthesia in small dogs

Background: Unlike other major reflexes contributing to hemodynamic homeostasis, the Bezold-Jarisch reflex (BJR)paradoxically decreases heart rate (HR) and mean arterial pressure (MAP) despite hypotension. In the veterinary field,there are few reported cases of BJR induced by dopamine, which is often used to manage hypotension. Herein, 2 casesinvolving small dogs exhibiting BJR due to dopamine infusion during general anesthesia are described.Cases: Case 1: A 7-year-old, 7 kg, mongrel was referred for external skeletal fixator removal. The patient was premedicatedwith 0.3 mg/kg midazolam and 0.2 mg/kg butorphanol intravenously (IV). General anesthesia was induced with 6 mg/kgpropofol and maintained with 1.6% isoflurane in oxygen. The patient was given 5 mL/kg/h of Hartmann’s solution IV. Therespiratory rate (RR) was set to 9 breaths/min with a ventilator. The HR and MAP values were initially 120 bpm and 76mmHg and gradually decreased to 70 bpm and 40 mmHg, respectively. The end-tidal CO2 partial pressure (ETCO2) was 39mmHg, and the patient was administered 2.5 μg/kg glycopyrrolate IV. Then, 5 μg/kg/min dopamine was administered IVsince the MAP did not improve. The HR, MAP, and ETCO2 increased to 113 bpm, 72 mmHg, and 47 mmHg, respectively.Subsequently, HR and MAP dramatically decreased to 50 bpm and 43 mmHg, respectively. A second-degree atrioventricularblock was detected, prompting dopamine infusion discontinuation, and 2.5 μg/kg glycopyrrolate was again administeredIV. Within 5 min, HR and MAP values normalized, and postoperative patient recovery was typical. Case 2: A 2-year-old,8.6 kg, mongrel underwent surgery to correct a medial luxating patella of the right leg. The patient was premedicated with0.3 mg/kg midazolam and 0.2 mg/kg butorphanol IV. Anesthesia was induced with 4 mg/kg propofol IV and maintained...

Bezold-Jarisch reflex induced by dopamine during isoflurane anesthesia in small dogs

Background: Unlike other major reflexes contributing to hemodynamic homeostasis, the Bezold-Jarisch reflex (BJR)paradoxically decreases heart rate (HR) and mean arterial pressure (MAP) despite hypotension. In the veterinary field,there are few reported cases of BJR induced by dopamine, which is often used to manage hypotension. Herein, 2 casesinvolving small dogs exhibiting BJR due to dopamine infusion during general anesthesia are described.Cases: Case 1: A 7-year-old, 7 kg, mongrel was referred for external skeletal fixator removal. The patient was premedicatedwith 0.3 mg/kg midazolam and 0.2 mg/kg butorphanol intravenously (IV). General anesthesia was induced with 6 mg/kgpropofol and maintained with 1.6% isoflurane in oxygen. The patient was given 5 mL/kg/h of Hartmanns solution IV. Therespiratory rate (RR) was set to 9 breaths/min with a ventilator. The HR and MAP values were initially 120 bpm and 76mmHg and gradually decreased to 70 bpm and 40 mmHg, respectively. The end-tidal CO2 partial pressure (ETCO2) was 39mmHg, and the patient was administered 2.5 μg/kg glycopyrrolate IV. Then, 5 μg/kg/min dopamine was administered IVsince the MAP did not improve. The HR, MAP, and ETCO2 increased to 113 bpm, 72 mmHg, and 47 mmHg, respectively.Subsequently, HR and MAP dramatically decreased to 50 bpm and 43 mmHg, respectively. A second-degree atrioventricularblock was detected, prompting dopamine infusion discontinuation, and 2.5 μg/kg glycopyrrolate was again administeredIV. Within 5 min, HR and MAP values normalized, and postoperative patient recovery was typical. Case 2: A 2-year-old,8.6 kg, mongrel underwent surgery to correct a medial luxating patella of the right leg. The patient was premedicated with0.3 mg/kg midazolam and 0.2 mg/kg butorphanol IV. Anesthesia was induced with 4 mg/kg propofol IV and maintained...(AU)

Aplicação intravenosa de metronidazol, ceftriaxona e enrofloxacina em cadelas anestesiadas com isoflurano: repercussão dos parâmetros hemodinâmicos e respiratórios / Intravenous application of metronidazole, ceftriaxone and enrofloxacin in dogs anesthetized with isoflurane: impact of hemodynamic and cardiorespiratory parameters

Background: The prophylactic use of antimicrobials in patients undergoing surgery is widely performed due to its power to reduce and control infections in the surgical site. Metronidazole, ceftriaxone and enrofloxacin are drugs widely used in veterinary medicine, even during anesthesia, either in healthy patients or under critical conditions. Despite several reports on hemodynamic reactions after intravenous application of antimicrobials in dogs, there are few studies on these effects in dogs undergoing anesthesia. The objective of this study was to evaluate the hemodynamic and cardiorespiratory effects of metronidazole, ceftriaxone and enrofloxacin in dogs anesthetized with isoflurane. Materials, Methods & Results: Forty healthy bitches were used, equally divided into four experimental groups of 10 animals each: placebo group (PG), metronidazole group (MG), ceftriaxone group (CG) and enrofloxacin group (EG). After the experimental phase of data collection, all animals were submitted to ovariohysterectomy using the minimally invasive approach. A catheter was placed in the dorsal metatarsal artery for direct blood pressure monitoring, with systolic (SBP), mean (MBP) and diastolic (DBP) blood pressures were continuously monitored by means of a transducer connected to a multiparametric monitor. The others measured data were heart rate (HR), respiratory rate (RR), body temperature (T°C), carbon dioxide expired fraction (ETCO2), oxygen saturation of hemoglobin (SpO2) in T0 (time immediately before performing the treatment), 5 (T5), 10 (T10), 15 (T15), 20 (T20) and 30 (T30) minutes after administration of the antimicrobial. Anesthetic induction was performed with propofol and anesthetic maintenance was performed with isoflurane. After reaching anesthesia with a surgical plan, all parameters were measured before treatments were performed (T0). Then the...

Prognostic values of physical and hematological parameters of dogs naturally infected with parvovirus PVC-2: retrospective study of 103 cases / [Valores prognósticos de parâmetros físicos e hematológicos de cães naturalmente infectados pelo parvovírus PVC-2: estudo retrospectivo de 103 casos]

Canine parvovirosis is a high mortality disease with acute clinical picture. However, there are few available resources to help stablish prognosis accurately. This study aimed to determine the prognostic threshold values for vital and hematological parameters of dogs naturally infected by the Carnivore protoparvovirus 1 (CPV). A retrospective study of 103 canine parvovirosis cases was carried out. Twenty seven percent of these (28/103) died, 96% (27/28) of which within the first four days of hospitalization. Deceased animals had significantly higher median values for heart (HR) and respiratory (f) rates, as well as significantly lower systolic blood pressure (SBP) than survivors. Severely leukopenic animals (<1,000 cells/µL), had a significantly higher mortality rate (68%, n=13) compared to that of other patients (P<0.0007). Animals with at least two of the following findings: severe hypotension (SBP< 90mmHg), tachycardia (HR > 150 bpm) and leukopenia, represented 34% (34/101) of the cases and had a survival rate of 29% (10/34), while animals with at most one of these parameters represented 66% (67/101) and had a survival rate of 94% (63/67). The presence of two or three abnormal parameters was significantly related to the higher death risk among dogs with parvovirosis (P<0.0001).(AU)

A parvovirose canina é uma doença de alta mortalidade e de quadro clínico agudo. No entanto, existem poucos recursos para se estabelecer prognóstico de maneira precisa. Este estudo objetivou analisar os valores prognósticos de parâmetros físicos e hematológicos de cães naturalmente infectados pelo Carnivore protoparvovirus 1 (CPV). Um estudo retrospectivo de 103 casos de parvovirose canina foi realizado. Desses, 27% dos animais (28/103) foram a óbito, sendo 96% (27/28) com ocorrência nos primeiros quatro dias de internamento. Os cães que foram a óbito apresentaram medianas das frequências cardíaca (FC) e respiratória (f) significativamente maiores e pressão arterial sistólica (PAS) consideravelmente menor que a dos sobreviventes. Entre os animais mais intensamente leucopênicos (<1.000 células/(L), a taxa de mortalidade (68%, n=13) foi expressivamente maior que a dos demais pacientes (P<0,0007). Os animais com hipotensão grave (PAS<90mmHg), taquicardia (FC>150bpm) e leucopenia intensa (leucometria<1.000 células/µL), ou duas dessas alterações clínicas, representaram 34% (34/101) dos casos e tiveram taxa de sobrevida de 29% (10/34), enquanto os animais com, no máximo, um desses parâmetros alterados representaram 66% (67/101) dos animais, com taxa de sobrevida de 94% (63/67). A presença de dois ou três parâmetros alterados esteve significativamente relacionada ao maior risco de óbito de cães com parvovirose (P<0,0001).(AU)

Hypotension aggravated by dopamine in a dog under isoflurane anesthesia

Background: Hypotension (MAP < 60 mmHg) is the most common complication in anesthetic practice and has been identified in 38% of canine patients undergoing general anesthesia for variety of procedures. Normalization of arterial pressure can usually be achieved by decreases in inhalant anesthetic concentrations, fluid administration, and use of inotropes/ vasopressors in healthy animals (ASA I) or animals with mild systemic disease (ASA anesthetic risk II). The present report shows an ASA II dog with severe hypotensive crisis [mean arterial pressure (MAP) < 50 mmHg] during general anesthesia, in which the procedure was aborted because hypotension was aggravated by dopamine.Case: A 7-year-old male Bull Terrier was anesthetized for magnetic resonance imaging (MRI) of a tumor in the face. After intramuscular acepromazine (0.01 mg/kg) and meperidine (3 mg/kg), anesthesia was induced with intravenous (IV) ketamine (1 mg/kg) and propofol (2.3 mg/kg) and maintained with isoflurane in oxygen. Ten min after induction of anesthesia MAP was 45 mmHg, while end-tidal isoflurane (ETISO) concentration was 0.5%. End-tidal isoflurane was decreased to 0.3% and an IV bolus of Lactated Ringer’s was initiated (15 mL/kg over 10 min), followed by two ephedrine boluses (0.1 mg/kg, IV) administered 5 min apart. MAP remained low (< 50 mmHg) and dopamine constant rate infusion (CRI) was initiated (7.5 μg/kg/min). Ten minutes after dopamine CRI was commenced, MAP was further decreased to 25-22 mmHg. Dopamine CRI was increased to 10 μg/kg/min, but MAP remained < 25 mmHg. Infusion drugs and isoflurane anesthesia were stopped. After the animal was extubated MAP returned 60-70 mmHg.Discussion: Among the drugs used, isoflurane is known for decreasing blood pressure in a dose-related manner because of its vasodilating properties.[...]

Hypotension aggravated by dopamine in a dog under isoflurane anesthesia

Background: Hypotension (MAP < 60 mmHg) is the most common complication in anesthetic practice and has been identified in 38% of canine patients undergoing general anesthesia for variety of procedures. Normalization of arterial pressure can usually be achieved by decreases in inhalant anesthetic concentrations, fluid administration, and use of inotropes/ vasopressors in healthy animals (ASA I) or animals with mild systemic disease (ASA anesthetic risk II). The present report shows an ASA II dog with severe hypotensive crisis [mean arterial pressure (MAP) < 50 mmHg] during general anesthesia, in which the procedure was aborted because hypotension was aggravated by dopamine.Case: A 7-year-old male Bull Terrier was anesthetized for magnetic resonance imaging (MRI) of a tumor in the face. After intramuscular acepromazine (0.01 mg/kg) and meperidine (3 mg/kg), anesthesia was induced with intravenous (IV) ketamine (1 mg/kg) and propofol (2.3 mg/kg) and maintained with isoflurane in oxygen. Ten min after induction of anesthesia MAP was 45 mmHg, while end-tidal isoflurane (ETISO) concentration was 0.5%. End-tidal isoflurane was decreased to 0.3% and an IV bolus of Lactated Ringers was initiated (15 mL/kg over 10 min), followed by two ephedrine boluses (0.1 mg/kg, IV) administered 5 min apart. MAP remained low (< 50 mmHg) and dopamine constant rate infusion (CRI) was initiated (7.5 μg/kg/min). Ten minutes after dopamine CRI was commenced, MAP was further decreased to 25-22 mmHg. Dopamine CRI was increased to 10 μg/kg/min, but MAP remained < 25 mmHg. Infusion drugs and isoflurane anesthesia were stopped. After the animal was extubated MAP returned 60-70 mmHg.Discussion: Among the drugs used, isoflurane is known for decreasing blood pressure in a dose-related manner because of its vasodilating properties.[...](AU)

Efficacy of use of tramadol in analgesia of prepubertal queens submitted to ovaryhysterectomy / Eficácia do uso de tramadol na analgesia de gatas pré púberes submetidas à ovariohisterectomia

É crescente o número de animais errantes nos grandes centros urbanos, sendo a população de felinos bastante significativa. A esterilização pré púbere promove de forma precoce a incapacidade reprodutiva do animal; reduz o desenvolvimento de patologias relacionadas ao trato reprodutivo, além de outras vantagens. Entretanto a anestesia em animais pré púberes ainda é um desafio e o uso de opióides nestes pacientes tem sido questionado devido a ocorrência de hipotensão em alguns casos. Sendo assim tornam-se necessários estudos para verificar as consequências do uso de opióides nestes animais. Portanto, o presente estudo teve como objetivo avaliar a eficiência do uso de Tramadol em gatas pré-púberes submetidas à ovariosalpingohisterectomia. Foram utilizadas oito fêmeas da espécie felina, com idade entre dois e quatro meses. As gatas foram divididas aleatoriamente em dois grupos (grupo Controle e grupo Tramadol), constituídos de 4 animais cada. Durante o trans operatório foram avaliadas a temperatura corporal, frequência respiratória, frequência cardíaca e saturação de oxigênio e pressão arterial não invasiva. Foram aferidos imediatamente antes da administração das drogas anestésicas (T0 – Controle) e a cada 4 minutos durante o transoperatório de 20 minutos (T4, T8, T12,T16, T20); os parâmetros de frequência cardíaca; frequência respiratória, temperatura corporal, nível de saturação de oxigênio e pressão arterial sistólica (PAS). O grupo Tramadol apresentou valores de frequência cardíaca e respiratória inferiores quando comparados com os obtidos no grupo Controle nos períodos de T0 até o T8. Em todos os momentos analisados a temperatura corporal e saturação de oxigênio não revelaram diferença significativa entre os dois grupos; sendo que os valores se mantiveram entre 35,6°C a 37,7°C e 78,5% a 90,25% respectivamente. Neste estudo foi possível concluir que o Tramadol foi eficiente na analgesia após esterilização...

The number of wandering animals in large urban centers is increasing, and the cat population is quite significant. Pre-pubertal sterilization promotes early reproductive failure of the animal; reduces the development of pathologies related to the reproductive tract, in addition of other advantages. However, anesthesia in prepubertal animals is still a challenge and the usage of opioids in those patient has been questioned due to the occurrence of hypotension in some cases. Accordingly, it is necessary further studies to verify the consequences of the use of opioids in these animals. Therefore, the present study had as objective to evaluate the effectiveness of the use of Tramadol in prepubescent queens submitted to ovariohisterectomy. Eight females of the feline species, aged between two and four months, were used. The queens were randomly divided into two groups (Control group and Tramadol group), consisting of four animals each. During the transoperative period, body temperature, respiratory rate, heart rate and oxygen saturation, and noninvasive blood pressure had been monitored. They have been measured immediately prior to administration of anesthetic drugs (T0 – Control) and every 4 minutes during 20 minute of transoperative period (T4, T8, T12, T16, T20); heart rate parameters; respiratory rate, body temperature, oxygen saturation level and systolic blood pressure (SBP). The Tramadol group presented lower values – of heart rate and respiratory rate when compared to those obtained in the Control group in the periods from T0 to T8. In all analyzed moments body temperature and oxygen saturation did not reveal significant difference between the two groups; with values – between 35.6° C and 37.7° C and 78.5% and 90.25%, respectively. In this study it was possible to conclude that Tramadol was efficient in analgesia after surgical sterilization of prepubertal cats, without causing significant hypotension.

Efficacy of use of tramadol in analgesia of prepubertal queens submitted to ovaryhysterectomy / Eficácia do uso de tramadol na analgesia de gatas pré púberes submetidas à ovariohisterectomia

É crescente o número de animais errantes nos grandes centros urbanos, sendo a população de felinos bastante significativa. A esterilização pré púbere promove de forma precoce a incapacidade reprodutiva do animal; reduz o desenvolvimento de patologias relacionadas ao trato reprodutivo, além de outras vantagens. Entretanto a anestesia em animais pré púberes ainda é um desafio e o uso de opióides nestes pacientes tem sido questionado devido a ocorrência de hipotensão em alguns casos. Sendo assim tornam-se necessários estudos para verificar as consequências do uso de opióides nestes animais. Portanto, o presente estudo teve como objetivo avaliar a eficiência do uso de Tramadol em gatas pré-púberes submetidas à ovariosalpingohisterectomia. Foram utilizadas oito fêmeas da espécie felina, com idade entre dois e quatro meses. As gatas foram divididas aleatoriamente em dois grupos (grupo Controle e grupo Tramadol), constituídos de 4 animais cada. Durante o trans operatório foram avaliadas a temperatura corporal, frequência respiratória, frequência cardíaca e saturação de oxigênio e pressão arterial não invasiva. Foram aferidos imediatamente antes da administração das drogas anestésicas (T0 Controle) e a cada 4 minutos durante o transoperatório de 20 minutos (T4, T8, T12,T16, T20); os parâmetros de frequência cardíaca; frequência respiratória, temperatura corporal, nível de saturação de oxigênio e pressão arterial sistólica (PAS). O grupo Tramadol apresentou valores de frequência cardíaca e respiratória inferiores quando comparados com os obtidos no grupo Controle nos períodos de T0 até o T8. Em todos os momentos analisados a temperatura corporal e saturação de oxigênio não revelaram diferença significativa entre os dois grupos; sendo que os valores se mantiveram entre 35,6°C a 37,7°C e 78,5% a 90,25% respectivamente. Neste estudo foi possível concluir que o Tramadol foi eficiente na analgesia após esterilização...(AU)

The number of wandering animals in large urban centers is increasing, and the cat population is quite significant. Pre-pubertal sterilization promotes early reproductive failure of the animal; reduces the development of pathologies related to the reproductive tract, in addition of other advantages. However, anesthesia in prepubertal animals is still a challenge and the usage of opioids in those patient has been questioned due to the occurrence of hypotension in some cases. Accordingly, it is necessary further studies to verify the consequences of the use of opioids in these animals. Therefore, the present study had as objective to evaluate the effectiveness of the use of Tramadol in prepubescent queens submitted to ovariohisterectomy. Eight females of the feline species, aged between two and four months, were used. The queens were randomly divided into two groups (Control group and Tramadol group), consisting of four animals each. During the transoperative period, body temperature, respiratory rate, heart rate and oxygen saturation, and noninvasive blood pressure had been monitored. They have been measured immediately prior to administration of anesthetic drugs (T0 Control) and every 4 minutes during 20 minute of transoperative period (T4, T8, T12, T16, T20); heart rate parameters; respiratory rate, body temperature, oxygen saturation level and systolic blood pressure (SBP). The Tramadol group presented lower values of heart rate and respiratory rate when compared to those obtained in the Control group in the periods from T0 to T8. In all analyzed moments body temperature and oxygen saturation did not reveal significant difference between the two groups; with values between 35.6° C and 37.7° C and 78.5% and 90.25%, respectively. In this study it was possible to conclude that Tramadol was efficient in analgesia after surgical sterilization of prepubertal cats, without causing significant hypotension.(AU)

Arterial, mixed venous or central venous hemogasometry and end tidal CO2 in dogs under different hemodynamic states

Background: Hemogasometric analysis is used in the interpretation of acid-base balance (ABB) and to access pulmonary ventilation. Already mixed venous oxygen saturation obtained at pulmonary artery correlates with tissue oxygenation. However, both samples can be difficult to access because of the difficulties in arterial and pulmonary catheterization. The aim of this study was to evaluate the feasibility of replacing the arterial and mixed venous bloods, the end tidal pressure of carbon dioxide (EtCO2 ) and central venous blood in the analysis of pulmonary ventilation, tissue oxygenation and ABB in dogs under different hemodynamic states. Material, Methods & Results: Nine dogs were used with an average weight of 19.6 ± 1.3 kg, anesthetized with isoflurane at 1.4 V% diluted on oxygen 60% (Baseline), and subsequently undergoing mechanical ventilation (MV) and the hypodinamic state (Hypo) with isoflurane at 3.5V% and mean arterial pressure (MAP) lower than 50 mmHg and hyperdynamic state (Hyper) by dobutamine infusion at 5 μg/kg/min and with MAP 30% higher than baseline. For each time allowed a 15 min of stabilization by each hemodynamic status. Simultaneously were collected samples of 0.6 mL of arterial blood by metatarsal artery, mixed and central venous blood by pulmonary artery and right atrium for hemogasometric analysis. To access lung function we correlated and compared the EtCO2 values obtained by gas analyzer with expired carbon dioxide pressure in the arterial blood (PaCO2 ), mixed venous blood (PmvCO2 ) and central venous blood (PcvCO2 ). For the interpretation of tissue oxygenation we correlated and compared the values of mixed (SmvO2 ) and central (ScvO2 ) venous oxygen saturation. For the acid-base balance we used the correlation of potencial hydrogen (pH); carbon dioxide pressure (PCO2 ); bicarbonate ion (HCO3-); base excess (BE); […](AU)

Arterial, mixed venous or central venous hemogasometry and end tidal CO2 in dogs under different hemodynamic states

Background: Hemogasometric analysis is used in the interpretation of acid-base balance (ABB) and to access pulmonary ventilation. Already mixed venous oxygen saturation obtained at pulmonary artery correlates with tissue oxygenation. However, both samples can be difficult to access because of the difficulties in arterial and pulmonary catheterization. The aim of this study was to evaluate the feasibility of replacing the arterial and mixed venous bloods, the end tidal pressure of carbon dioxide (EtCO2 ) and central venous blood in the analysis of pulmonary ventilation, tissue oxygenation and ABB in dogs under different hemodynamic states. Material, Methods & Results: Nine dogs were used with an average weight of 19.6 ± 1.3 kg, anesthetized with isoflurane at 1.4 V% diluted on oxygen 60% (Baseline), and subsequently undergoing mechanical ventilation (MV) and the hypodinamic state (Hypo) with isoflurane at 3.5V% and mean arterial pressure (MAP) lower than 50 mmHg and hyperdynamic state (Hyper) by dobutamine infusion at 5 μg/kg/min and with MAP 30% higher than baseline. For each time allowed a 15 min of stabilization by each hemodynamic status. Simultaneously were collected samples of 0.6 mL of arterial blood by metatarsal artery, mixed and central venous blood by pulmonary artery and right atrium for hemogasometric analysis. To access lung function we correlated and compared the EtCO2 values obtained by gas analyzer with expired carbon dioxide pressure in the arterial blood (PaCO2 ), mixed venous blood (PmvCO2 ) and central venous blood (PcvCO2 ). For the interpretation of tissue oxygenation we correlated and compared the values of mixed (SmvO2 ) and central (ScvO2 ) venous oxygen saturation. For the acid-base balance we used the correlation of potencial hydrogen (pH); carbon dioxide pressure (PCO2 ); bicarbonate ion (HCO3-); base excess (BE); […]

Ovariossalpingo-histerectomia em cadelas: comparação da dor e análises cardiorrespiratória, pressórica e hemogasométrica nas abordagens convencional, por NOTES híbrida e NOTES total / Ovariosalpingohisterectomy in bitches: comparison of pain, cardiopulmonary, pressure and arterial blood gas analysis of the conventional approaches, by NOTES hybrid and NOTES pure

A cirurgia endoscópica por orifícios naturais (NOTES) é um novo conceito de abordagem videocirúrgica, que surge como alternativa à cirurgia convencional, eliminando incisões abdominais e as possíveis complicações relacionadas a ela. A proposta deste artigo foi comparar técnicas de ovariossalpingo-histerectomia (OSH) em cadelas, buscando determinar o procedimento que oferece menores alterações hemodinâmicas e menos estímulos dolorosos trans e pós-operatório. Para tanto, foram utilizadas 21 cadelas alocadas em três grupos. No primeiro, os pacientes foram submetidos à OSH por celiotomia (GC), no segundo por meio da técnica de NOTES híbrida (GNH) e no terceiro (GNT), utilizando-se a técnica de NOTES total. O tempo cirúrgico do GNH foi significativamente maior que nos demais grupos. Em ambos os grupos de cirurgia NOTES, verificou-se diminuição das pressões arteriais médias e diastólicas no transoperatório. Apenas o grupo GNH desenvolveu acidose severa no transoperatório. Levando-se em consideração as avaliações da dor, apenas o grupo convencional necessitou de analgesia resgate transcirúrgica. No pós-operatório, observou-se que os cães do GC apresentaram índices mais elevados na escala visual analógica e na escala de Melbourne que os animais dos demais grupos, sendo necessária analgesia resgate em 100% deles. Em contraste, no GNT nenhum dos cães requereram complementação analgésica pós-operatória. Conclui-se que a técnica de OSH por NOTES total apresenta parâmetros cardiorrespiratórios e hemogasométricos semelhantes à técnica convencional e mais estáveis que a técnica de NOTES híbrida, bem como resulta em menor dor trans e pós-operatória que a técnica convencional.(AU)

The aim of the present study was to perform bacteriological and molecular methods for identification of Mycobacterium bovis in lesions derived from bovine carcasses detected during routine post-mortem examination in officially inspected slaughterhouses. We checked the slaughter and inspection of 825,394 bovines, health upon ante-mortem examination, by the official service in 10 slaughterhouses of Bahia state from April, 2009 to April 2012. Lesions suggestive of tuberculosis were collected from 180 bovines and further evaluated by bacteriology and multiplex PCR. The majority of lesions were located in the respiratory tract lymph nodes and 71% were from male bovines up to 32 months old. 13.9% of samples presented small, granular and creamy-yellowish colonies after being cultured in Stonebrink-Leslie with an average growth time of 34 days. All smears from the isolated samples were Acid Fast Bacilli (AFB) and among them 56% were identified by mPCR as M. bovis. Thus, the association between post-mortem examination, culture and multiplex PCR allowed the bacillus identification in a reduced time and in regions of low prevalence, pointing out its importance for bovine tuberculosis detection and as a supportive tool for the tuberculosis control and eradication program.(AU)

Eletroacupuntura para tratamento de hipotensão induzida por isofluorano em cavalos / Electroacupuncture treatment for isoflurane induced hypotension in horses

Objetivou-se avaliar a eficiência do tratamento da hipotensão arterial com eletroacupuntura comparativamente à dobutamina em equinos. Foram avaliados seis cavalos adultos, saudáveis, mantidos em anestesia inalatória, com isofluorano, em ventilação mecânica. Após a estabilização da anestesia, foi induzida hipotensão arterial, através do incremento da concentração do isofluorano, iniciando-se um dos tratamentos: DOB: dobutamina (1,5µg kg-1 min-1, infusão contínua intravenosa); EA: estímulo elétrico no acuponto pericárdio 6 (PC6), bilateralmente; SHAM: estímulo elétrico em ponto falso de acupuntura. Foram mensurados: frequência cardíaca (FC), pressão arterial média (PAM), temperatura retal (T), concentração final expirada de isofluorano (ETiso), variáveis hemogasométricas, concentração sérica de aspartato aminotransferase (AST) e creatina fosfoquinase (CK), tempo e qualidade da recuperação pós-anestésica. Houve incremento na PAM de 50%, 36,6% e 7,5% nos tratamentos DOB, EA e SHAM, respectivamente. Não houve diferença entre os grupos nas variáveis hemogasométricas, FC, T, ETiso, CK, AST, tempo e qualidade de recuperação pós-anestésica. Conclui-se que o tratamento com dobutamina foi mais efetivo para o tratamento da hipotensão em cavalos sob anestesia inalatória quando comparado ao estímulo elétrico do acuponto PC6 ou ponto falso de acupuntura.(AU)

This study aimed to evaluate the efficacy of electroacupuncture compared to the dobutamine treatment of hypotension in equines. Six adult horses were maintained in isoflurane anesthesia with mechanical ventilation. After anesthesia was established, the isoflurane concentration was raised until hypotension was achieved. After that the animals were treated with a constant rate of 1.5mg kg -1min-1 intravenous dobutamine (DOB), electroacupunture to pericardium 6 (PC-6) acupoint (EA) and false point treatment (SHAM). Heart rate (HH), median arterial blood pressure (MAP), rectal temperature (T), isoflurane end-tidal concentration, arterial blood gases, creatine kinase (CK), aspartate transaminase (AST), recovery time and quality of recovery were investigated. The MAP increased 50%, 36.5% and 7.5%% in DOB, EA and SHAM treatments, respectively. HH, T, arterial blood gases, CK, AST, recovery time and quality of recovery did not differ among treatments. It was concluded that the dobutamine treatment was more effective than EA and SHAM treatments for the reversion of isoflurane induced hypotension in horses.(AU)

Tepoxalin on renal function and liver enzymes in cats exposed to hypotension with isoflurane / Tepoxalina sobre a função renal e as enzimas hepáticas em gatos submetidos à hipotensão com isofluorano

Este estudo teve como objetivo a avaliação da possível toxicidade renal e hepática da tepoxalina administrada antes ou após hipotensão induzida por isofluorano, assim como a sua administração nos cinco dias seguintes à hipotensão. 12 gatos adultos hígidos, machos, sem raça definida e com peso de 4,0±0,8kg foram alocados em dois grupos (n=6). Os animais receberam 25mgkg-1 de tepoxalina pela via oral, duas horas antes do procedimento anestésico (PRE) ou após o procedimento (POST) e diariamente por cinco dias consecutivos. Os gatos foram anestesiados com isofluorano, aumentando-se a sua concentração até que se atingisse uma pressão arterial média entre 40 e 60mmHg, sendo mantida durante 60 minutos. Durante o procedimento de hipotensão, os parâmetros fisiológicos foram mensurados no tempo 0 e a cada dez minutos até o fim do procedimento. O tempo de sangramento da mucosa oral foi avaliado no tempo 0 e aos 30 e 60 minutos de hipotensão. Amostras sanguíneas foram colhidas para a determinação de hemograma, alanina aminotransferase, fosfatase alcalina, ureia, creatinina e sódio no período basal e às 24 horas, 48 horas e sete dias pós-hipotensão. Amostras de urina foram colhidas por meio de cistocentese para a determinação de creatinina, gammaglutamiltransferase, densidade específica, proteínas, albumina e sódio. Durante o período anestésico, não ocorreram alterações referentes aos parâmetros fisiológicos e ao tempo de sangramento. Ocorreram alterações apenas na excreção fracionada de sódio, a qual demonstrou elevação no PRE aos sete dias, e na razão proteína/creatinina na urina, a qual demonstrou elevação do PRE em relação ao POST às 24 e às 48 horas de avaliação. Concluiu-se que a tepoxalina não causou alterações nas enzimas hepáticas, mas pode causar discreta injúria renal, com a presença de proteinúria, em gatos que foram submetidos à hipotensão.(AU)

This study aimed to evaluate the possible renal and hepatic toxicity of tepoxalin administered before or after isoflurane-induced hypotension, as well as for five consecutive days. Twelve healthy mixed-breed cats, adult males, weighing 4.0±0.8kg were allocated into two groups. They received 25mgkg-1 of tepoxalin orally, two hours before the anesthetic procedure (PRE) or after the procedure (POST) and daily for five days. Cats were anesthetized with isoflurane and the concentration was increased until mean arterial pressure reached 40-60mmHg and kept at this level for 60 minutes. During hypotension, the physiological variables were measured at time 0 and every 10 minutes until 60 minutes, and bleeding time was measured at time 0, 30 and 60 minutes. Blood samples were drawn for a hemogram and determination of concentrations of alanine aminotransferase, alkaline phosphatase, urea, creatinine and Na+ at baseline, 24 hours, 48 hours and 7 days post-hypotension. Urine was collected at baseline, 24 hours, 48 hours and 7 days post-hypotension for determination of concentrations of creatinine, gamma-glutamyltransferase, urine specific gravity, protein, albumin and Na+. During the anesthetic procedure there were no important variations in physiological variables and bleeding time. There were differences only in fractional excretion of Na+, which was elevated at 7 days of evaluation in PRE and in the urine protein/creatinine ratio in PRE, which was higher than in POST at 24 and 48 hours post-hypotension. We conclude that tepoxalin does not cause alterations in hepatic enzymes but can cause discrete renal injury, resulting in proteinuria, in cats subjected to 60min of hypotension.(AU)

Hemodynamic and antiarrhythmic effects of lidocaine or amiodarone in dogs anesthetized with halothane / Efeitos hemodinâmicos e antiarrítmicos da lidocaína ou amiodarona em cães anestesiados com halotano

The effects of continuous rate infusion of lidocaine or amiodarone on hemodynamic and arrhythmias induced by epinephrine in dogs anesthetized with halothane were evaluated. Thirty dogs were distributed into three groups: amiodarone group (AG), lidocaine group (LG), or control group (CG). Anesthesia was induced with etomidate and maintained with halothane. Thirty minutes later a bolus and continuous rate infusion (CRI) of amiodarone in AG, lidocaine in LG and NaCl at 0.9% in CG was administered. After 10 minutes, arrhythmias were induced by epinephrine CRI at 0.0001mg/kg/minute, which was increased in 0.0001mg/kg/minute every ten minutes, until 0.0003mg/kg/minute. The measurements were performed 30 minutes after the induction of anesthesia (T0), 10 minutes after beginning the drug CRIs (T1), 10 minutes after beginning epinephrine administration (T2) and 10 minutes after increasing epinephrine CRI (T3 and T4). In CG, at T3 heart rate (HR) was greater than in LG, while at T4, HR in GC was higher than in LG and AG. In LG and CG, from T2, central venous pressure (CVP), cardiac index (CI), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP), mean pulmonary arterial pressure (mPAP) increased. In AG, SAP, DAP and MAP it decreased from T1 to T3. The ventricular ectopic beats (VEB) were lower in AG. Amiodarone has better antiarrhythmogenic effects, although it was also associated with hypotension.(AU)

Avaliaram-se os efeitos da infusão contínua de lidocaína ou amiodarona sobre a hemodinâmica e as arritmias induzidas pela epinefrina em cães anestesiados com halotano. Trinta animais foram distribuídos em três grupos: grupo amiodarona (GA), grupo lidocaína (GL) ou grupo-controle (GC). A anestesia foi induzida com etomidato e mantida com halotano. Trinta minutos após, foram administrados bolus e infusão contínua (CRI) de amiodarona no GA, de lidocaína no GL e de NaCl a 0,9% no GC. Após 10 minutos, iniciou-se a CRI de epinefrina (0,0001mg/kg/minuto), aumentando-se 0,0001mg/kg/minuto a cada 10 minutos até 0,0003mg/kg/minuto. As mensurações foram realizadas 30 minutos após a indução anestésica (T0), 10 minutos após a CRI dos fármacos (T1), 10 minutos após a administração de epinefrina (T2) e a cada 10 minutos após o incremento na CRI de epinefrina (T3 e T4). A frequência cardíaca (FC) foi maior no GC que no GL em T3 e maior em GC que nos demais grupos em T4. A partir de T2, houve aumento na pressão venosa central (PVC), no índice cardíaco (IC), nas pressões arteriais sistólica (PAS), diastólica (PAD) e média (PAM) e na pressão média da artéria pulmonar (PAPm) no GL e no GC. No GA, PAS, PAD e PAM diminuíram de T1 a T3. Os batimentos ventriculares ectópicos (BVE) foram menores no GA. Amiodarona possui melhores efeitos antiarrítmicos, apesar de também estar associada com hipotensão.(AU)

Manejo emergencial do hipoadrenocorticismo em cão – relato de caso / Emergency management of hypoadrenocorticism in dog – case report

O hipoadrenocorticismo é uma endocrinopatia incomum de difícil diagnóstico em cães (ROMÃO e ANTUNES, 2012). Os sinais clínicos são bastante variáveis, e o paciente pode apresentar desde uma simples gastroenterite até sinais de fraqueza e coma, em decorrência da falta de glicocorticóides e mineralocorticóides (ROMÃO e ANTUNES, 2012). O tratamento consiste em restabelecer rapidamente a volemia, principalmente na crise adrenal aguda, com administração de fluidoterapia intravenosa e glicocorticóide (EMANUELLI et al., 2007). O presente trabalho objetiva relatar o tratamento emergencial de um caso de hipoadrenocortiscismo em uma cadela.

Manejo emergencial do hipoadrenocorticismo em cão relato de caso / Emergency management of hypoadrenocorticism in dog case report

O hipoadrenocorticismo é uma endocrinopatia incomum de difícil diagnóstico em cães (ROMÃO e ANTUNES, 2012). Os sinais clínicos são bastante variáveis, e o paciente pode apresentar desde uma simples gastroenterite até sinais de fraqueza e coma, em decorrência da falta de glicocorticóides e mineralocorticóides (ROMÃO e ANTUNES, 2012). O tratamento consiste em restabelecer rapidamente a volemia, principalmente na crise adrenal aguda, com administração de fluidoterapia intravenosa e glicocorticóide (EMANUELLI et al., 2007). O presente trabalho objetiva relatar o tratamento emergencial de um caso de hipoadrenocortiscismo em uma cadela.(AU)

Hipotensão arterial em cães e gatos – revisão / Arterial hypotension in dogs and cats - a review / Hipotensión arterial en perros y gatos - revisión

A hipotensão arterial é intercorrência frequente na rotina clínica e cirúrgica de pequenos animais, provocando graves consequências, como injúria renal aguda ou mesmo disfunção de múltiplos órgãos. Entender a fisiopatologia e conhecer as opções diagnósticas e terapêuticas dessa intercorrência são condições fundamentais para uma correta abordagem nesses casos. O objetivo deste estudo foi revisar a fisiopatologia da hipotensão arterial, mas principalmente descrever os principais métodos de diagnóstico e as recentes diretrizes de seu tratamento. A atual terapia guiada por metas direciona o profissional para o entendimento da necessidade de uma ação terapêutica precoce a partir do diagnóstico da hipotensão. Dessa forma, por meio de um rápido restabelecimento da pressão arterial, espera-se reduzir ou mesmo prevenir sequelas dessa síndrome clínica potencialmente fatal.

Hypotension is an usual event in small animals clinics, which can impact severely the clinical outcome of patients by causing acute kidney injury or multiple organ failure. It is fundamental to understand the physiopathology of this condition and to know the main diagnosis and therapeutic options to deal correctly with such cases. Therefore, the aim of this study was to briefly review the physiopathology of hypotension and to describe the main diagnostic methods, as well as the most recent treatment guidelines. The current goal-based therapy helps the professional to understand the need for an early therapeutic action as soon hypotension is diagnosed. Thus, one expects to decrease or even prevent major sequelae through a rapid return to normal blood pressure in this potentially fatal clinical syndrome.

La hipotensión es una complicación frecuente en la clínica y cirugía de pequeños animales que tiene consecuencias graves como la insuficiencia renal aguda o la falia de múltiples órganos. La comprensión de la fisiopatología y el reconocimiento de las opciones diagnósticas y terapêuticas de esta complicación son fundamentales para el correcto manejo de estos casos. EI objetivo de este trabajo fue revisar la literatura relacionada con la fisiopatología de la hipotensión arterial, describiendo, principalmente, los métodos más importantes para su diagnóstico, y las directrices recientes en cuanto al tratamiento. La terapêutica actual a través de metas guía al profesional en la comprensión de la necesidad de una acción terapêutica precoz a partir dei diagnóstico de la hipotensión. De esa forma, a través de uma recuperación rápida de la presión arterial, se espera reducir o prevenir las posibles secuelas de este síndrome clínico potencialmente fatal.

Hipotensão arterial em cães e gatos revisão / Arterial hypotension in dogs and cats - a review / Hipotensión arterial en perros y gatos - revisión

A hipotensão arterial é intercorrência frequente na rotina clínica e cirúrgica de pequenos animais, provocando graves consequências, como injúria renal aguda ou mesmo disfunção de múltiplos órgãos. Entender a fisiopatologia e conhecer as opções diagnósticas e terapêuticas dessa intercorrência são condições fundamentais para uma correta abordagem nesses casos. O objetivo deste estudo foi revisar a fisiopatologia da hipotensão arterial, mas principalmente descrever os principais métodos de diagnóstico e as recentes diretrizes de seu tratamento. A atual terapia guiada por metas direciona o profissional para o entendimento da necessidade de uma ação terapêutica precoce a partir do diagnóstico da hipotensão. Dessa forma, por meio de um rápido restabelecimento da pressão arterial, espera-se reduzir ou mesmo prevenir sequelas dessa síndrome clínica potencialmente fatal.(AU)

Hypotension is an usual event in small animals clinics, which can impact severely the clinical outcome of patients by causing acute kidney injury or multiple organ failure. It is fundamental to understand the physiopathology of this condition and to know the main diagnosis and therapeutic options to deal correctly with such cases. Therefore, the aim of this study was to briefly review the physiopathology of hypotension and to describe the main diagnostic methods, as well as the most recent treatment guidelines. The current goal-based therapy helps the professional to understand the need for an early therapeutic action as soon hypotension is diagnosed. Thus, one expects to decrease or even prevent major sequelae through a rapid return to normal blood pressure in this potentially fatal clinical syndrome.(AU)

La hipotensión es una complicación frecuente en la clínica y cirugía de pequeños animales que tiene consecuencias graves como la insuficiencia renal aguda o la falia de múltiples órganos. La comprensión de la fisiopatología y el reconocimiento de las opciones diagnósticas y terapêuticas de esta complicación son fundamentales para el correcto manejo de estos casos. EI objetivo de este trabajo fue revisar la literatura relacionada con la fisiopatología de la hipotensión arterial, describiendo, principalmente, los métodos más importantes para su diagnóstico, y las directrices recientes en cuanto al tratamiento. La terapêutica actual a través de metas guía al profesional en la comprensión de la necesidad de una acción terapêutica precoz a partir dei diagnóstico de la hipotensión. De esa forma, a través de uma recuperación rápida de la presión arterial, se espera reducir o prevenir las posibles secuelas de este síndrome clínico potencialmente fatal.(AU)

Hemodynamic and thermoregulatory effects of xylazine-ketamine mixture persist even after the anesthetic stage in rats / Efeitos hemodinâmicos e termorregulatórios da mistura cetamina-xilasina persistem mesmo após o período anestésico em ratos

The xylazine-ketamine mixture (KX) is an anesthetic approach commonly administered to assess cardiovascular function in rodents. This study aimed to examine if the cardiovascular and thermoregulatory effects of KX could persist after the anesthetic state ceased in rats. Male Wistar rats were anesthetized with K (50mg/kg) X (10mg/kg) through the intra-peritoneal route. Hemodynamic and thermoregulatory repercussions were evaluated in animals in awake state, during an anesthetic depth and after complete recovery of anesthetized state. KX was efficient to significantly induce deep anesthesia in all rats after 10min. A complete recovery of anesthetized state was observed only after 210min. Compared with preanesthetic state and control animals that received no drug, KX induced a significant reduction of systolic and diastolic blood pressure at 10min. Hypotension was more prominent at 150min. The heart rate was also significantly reduced after 10 min of KX and the highest magnitude of bradycardia was observed at 30min. In addition, rectal temperature was markedly decreased at 30min of KX and the higher reduction occurred at 150min. The hemodynamic and thermoregulatory effects of KX were maintained even after complete anesthetic recovery.(AU)

Objetivou-se com este estudo avaliar a persistência dos efeitos cardiovasculares e termorregulatórios da associação cetamina e xilasina (CX) mesmo após o período anestésico em ratos. Ratos Wistar machos foram anestesiados com cetamina 50mg/kg e xilasina 10mg/kg, por via intra-peritoneal. As repercussões hemodinâmica e termorregulatória foram avaliadas com os animais acordados, durante o período anestésico e após recuperação completa da anestesia. A CX foi eficiente em induzir significante regime anestésico em todos os ratos após 10min. A recuperação completa do estado de anestesia foi observada somente após 210min. Comparado com o estado pré-anestésico e com animais controles, que não receberam anestesia, a CX induziu significativa redução das pressões sistólica e diastólica aos 10min. A hipotensão foi mais evidente aos 150min após CX. A frequência cardíaca também foi significativamente reduzida com 10min de CX e a bradicardia foi mais acentuada aos 30min. A temperatura retal foi reduzida aos 30min, sendo mais acentuada após 150min de anestesia. Os efeitos hemodinâmicos e termorregulatórios da CX persistem mesmo após completa recuperação anestésica.(AU)

Influence of S(+)-ketamine analgesia in renal intraoperative ischemia: histological study in rats / Influência da analgesia com S(+)-cetamina em isquemia renal intra-operatória. Estudo histológico em ratos

OBJETIVO: Investigar, em ratos, o efeito da S(+)cetamina na histologia renal após hemorragia intra-operatória.MÉTODOS: Vinte ratos Wistar machos, anestesiados com pentobarbital sódico, foram divididos, aleatoriamente, em 2 grupos: G1 û controle (n=10) e G2 - S(+)cetamina (n=10), submetidos a hemorragia de 30% da volemia em 3 momentos (10% a cada 10 min) 60 min após anestesia. G2 recebeu S(+)cetamina, 15 mg. kg-1, i.m., 5 min após anestesia e 55 min antes do 1.º momento de hemorragia (M1). Foram monitorizadas a pressão arterial média (PAM), temperatura retal (T) e freqüência cardíaca. Os animais foram sacrificados (M4) 30 min após o 3.º momento de hemorragia (M3). Os rins e o sangue das hemorragias foram utilizados para estudo histológico e do hematócrito (Ht). RESULTADOS: Houve redução significativa da PAM, T e Ht. Na histologia, G1=G2 na dilatação tubular, congestão e necrose. A soma total dos escores foi significativamente diferente e G2>G1. CONCLUSÃO: Hemorragia e hipotensão determinaram alterações na histologia renal. O aumento da concentração sangüínea de catecolaminas provavelmente determinou escores mais altos de alterações histológicas com o uso de S(+)cetamina.(AU)

PURPOSE: To study in rats the effect of S(+)¬ketamine on the renal histology after intraoperative hemorrhage. METHODS: Twenty male Wistar rats, anesthetized with sodium pentobarbital, were randomly divided in 2 groups: G1 - control (n=l0) and G2 - S(+)-ketamine (n=10), both submitted to arterial hemorrhage of 30% of volemia in 3 moments (10% each 10 min) 60 min after anesthesia. G2 received S(+)-ketamine, 15 mg. kg-1, i.m., 5 min after anesthesia and 55 min before the 1st hemorrhage moment (Ml). Medium arterial pressure (MAP), rectal temperature (T) and heart rate were monitored. The animals were sacrificed in M4, 30 min after the 3rd hemorrhage moment (M3) and the kidneys and blood collected from hemorrhage were utilized for histological study and hematocrit (Ht) determination. RESULTS: There were significant reduction of MAP, T, and Ht. The histological study verified G1 = G2 for tubular dilation, congestion, and necrosis. The total score addition were significant1y different and G2 > G 1. CONCLUSION: Hemorrhage and hypotension determined changes in kidney histology. The rise in catecholamine blood concentration probably was the cause of S(+)-ketamine-induced higher score of histological changes.(AU)