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)

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)

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...

Pharmacological evaluation of the hydro-alcoholic extract of Campomanesia phaea fruits in rats / Avaliação farmacológica do extrato hidroalcoólico dos frutos da Campomanesia phaea em ratos

Campomanesia phaea (Myrtaceae), popularly known as cambuci, is one of several species of plants producing comestible fruits, largely used in human nutrition. Despite its consumption and economic potential, limited scientific research is available on the Campomanesia, especially those related to its therapeutic benefits. It is reported by traditional medicine the use of the plant in the treatment of different disorders, such as cardiovascular and nervous system disturbances. So, the aim of this study was to carry out the pharmacological evaluation of the hydro-alcoholic extract (HAE) of Campomanesia fruits in rats by screening consisting of tests: a) neuropharmacological observation, b) test on the cardiovascular system. The HAE, prepared from the extraction of fruits with water/ethanol, was concentrated and freeze-dried. Behavioral responses in rats were investigated in open field test and the cardiovascular actions were investigated by a register of indirect blood pressure and the register of spontaneous beating rate right atrium. The results revealed that HAE induced grooming, hypotension and bradycardia. So, this study identified an action on the central nervous system, represented by grooming, and a cardiovascular activity of Campomanesia. The hypotension, attributed in part to bradycardia, was not related to a cholinergic effect, discarding a possible cholinomimetic action of the plant that could justify both cardiovascular and central actions.(AU)

Campomanesia phaea (Myrtaceae), popularmente conhecida como cambuci, é uma das várias espécies de plantas que produzem frutos comestíveis amplamente utilizados na nutrição humana. Apesar de seu consumo e potencial econômico, há poucas pesquisas científicas sobre a Campomanesia, especialmente aquelas relacionadas aos seus benefícios terapêuticos. É relatado pela medicina tradicional o uso da planta no tratamento de diferentes distúrbios, tais como distúrbios do sistema nervoso e cardiovascular. Assim, o objetivo deste estudo foi realizar a avaliação farmacológica do extrato hidroalcoólico (EHA) dos frutos de Campomanesia phaea em ratos através de triagem composta pelos testes: a) observação neurofarmacológica, b) testes no sistema cardiovascular. O EHA, preparado a partir da extração de frutos com água/etanol, foi concentrado e liofilizado. As respostas comportamentais em ratos foram investigadas em teste de campo aberto e as ações cardiovasculares foram investigadas pelo registro da pressão arterial indireta e o registro da taxa de batimentos cardíacos espontâneos em preparações isoladas de átrio direito. Os resultados revelaram que EHA induziu grooming, hipotensão e bradicardia. Assim, este estudo identificou uma ação da Campomanesia sobre o sistema nervoso central, representada por grooming, e uma atividade cardiovascular. A hipotensão, atribuída em parte à bradicardia, não está relacionada a um efeito colinérgico, descartando uma possível ação colinomimética da planta que pudesse justificar tanto as ações cardiovasculares quanto as centrais.(AU)

Pharmacological evaluation of the hydro-alcoholic extract of Campomanesia phaea fruits in rats

Abstract Campomanesia phaea (Myrtaceae), popularly known as cambuci, is one of several species of plants producing comestible fruits, largely used in human nutrition. Despite its consumption and economic potential, limited scientific research is available on the Campomanesia, especially those related to its therapeutic benefits. It is reported by traditional medicine the use of the plant in the treatment of different disorders, such as cardiovascular and nervous system disturbances. So, the aim of this study was to carry out the pharmacological evaluation of the hydro-alcoholic extract (HAE) of Campomanesia fruits in rats by screening consisting of tests: a) neuropharmacological observation, b) test on the cardiovascular system. The HAE, prepared from the extraction of fruits with water/ethanol, was concentrated and freeze-dried. Behavioral responses in rats were investigated in open field test and the cardiovascular actions were investigated by a register of indirect blood pressure and the register of spontaneous beating rate right atrium. The results revealed that HAE induced grooming, hypotension and bradycardia. So, this study identified an action on the central nervous system, represented by grooming, and a cardiovascular activity of Campomanesia. The hypotension, attributed in part to bradycardia, was not related to a cholinergic effect, discarding a possible cholinomimetic action of the plant that could justify both cardiovascular and central actions.

Resumo Campomanesia phaea (Myrtaceae), popularmente conhecida como cambuci, é uma das várias espécies de plantas que produzem frutos comestíveis amplamente utilizados na nutrição humana. Apesar de seu consumo e potencial econômico, há poucas pesquisas científicas sobre a Campomanesia, especialmente aquelas relacionadas aos seus benefícios terapêuticos. É relatado pela medicina tradicional o uso da planta no tratamento de diferentes distúrbios, tais como distúrbios do sistema nervoso e cardiovascular. Assim, o objetivo deste estudo foi realizar a avaliação farmacológica do extrato hidroalcoólico (EHA) dos frutos de Campomanesia phaea em ratos através de triagem composta pelos testes: a) observação neurofarmacológica, b) testes no sistema cardiovascular. O EHA, preparado a partir da extração de frutos com água/etanol, foi concentrado e liofilizado. As respostas comportamentais em ratos foram investigadas em teste de campo aberto e as ações cardiovasculares foram investigadas pelo registro da pressão arterial indireta e o registro da taxa de batimentos cardíacos espontâneos em preparações isoladas de átrio direito. Os resultados revelaram que EHA induziu grooming, hipotensão e bradicardia. Assim, este estudo identificou uma ação da Campomanesia sobre o sistema nervoso central, representada por grooming, e uma atividade cardiovascular. A hipotensão, atribuída em parte à bradicardia, não está relacionada a um efeito colinérgico, descartando uma possível ação colinomimética da planta que pudesse justificar tanto as ações cardiovasculares quanto as centrais.

Anesthetic complications in diabetic dogs subjected to phacoemulsification / Complicações anestésicas em cães diabéticos submetidos a facoemulsificação

The aim of this paper was to compare the incidence of anesthetic complications in diabetic and nondiabetic dogs subjected to phacoemulsification. In total, 30 male and female dogs of different breeds were used. The dogs were distributed into two groups: diabetic (DG) (n=15) and control (CG) (n=15). The animals were premedicated with acepromazine (0.03mg/kg) and meperidine (4mg/kg), intramuscularly. After 20 minutes, anesthesia was induced with propofol (2 to 5mg/kg) and maintained with isoflurane. The animals were monitored and the heart rate, respiratory rate, peripheral oxyhemoglobin saturation, end tidal carbon dioxide tension, inspired and expired isoflurane fraction, and invasive arterial pressure were recorded at 10 minute intervals during the surgical procedure. Arterial hemogasometry was performed after anesthetic induction (T0) and at the end of the surgical procedure. Diabetic patients (DG 10±2 years) were older than non-diabetic group (CG 6±2 years). The expired isoflurane fraction after induction was 30% higher in the control group (CG 1.3±0.3%, DG 1.0±0.2%) (p<0.01). The most common anesthetic complication was hypotension. In total, 80% of the diabetic animals (n=12) exhibited mean arterial pressure (MAP) lower than 60mmHg (54±9.6mmHg) after anesthetic induction, and 83% of the hypotensive dogs (n=10) required vasoactive drugs to treat hypotension. Regarding hemodynamic changes, diabetic patients subjected to general anesthesia were more likely to exhibit hypotension which may be due to the response of older animals to the drugs used; however, this change deserves further investigation.(AU)

O objetivo do presente estudo foi comparar a incidência de complicações anestésicas em cães diabéticos e não diabéticos submetidos a cirurgia de facoemulsificação. Foram utilizados 30 cães, machos ou fêmeas de diversas raças. Os cães foram distribuídos em dois grupos: diabético (GD) (n=15) e controle (GC) (n=15). Os animais foram pré-tratados com acepromazina (0,03mg/kg) e meperidina (4mg/kg), pela via intramuscular. Após 20 minutos, a indução foi realizada com propofol (2 a 5mg/kg) e a manutenção da anestesia com isofluorano. Os animais foram monitorados e as variáveis de frequência cardíaca, frequência respiratória, saturação oxihemoglobina periférica, concentração dióxido de carbono no final da expiração, fração inspirada e expirada de isofluorano e pressão arterial invasiva, foram registradas em intervalos de 10 minutos durante o procedimento cirúrgico. A hemogasometria arterial foi realizada após a indução (T0) e ao final do procedimento cirúrgico (T40). A idade dos animais do grupo diabético (10±2 anos) foi superior em relação aos animais do grupo controle (6±2 anos) (p<0,0001). A concentração expirada de isofluorano após a indução foi 30% superior nos animais do grupo controle (GC 1,3±0,3%, GD 1,0±0,2%) (p<0,01). A complicação anestésica mais comum foi a hipotensão arterial, 80% dos animais diabéticos (n=12) apresentaram pressão arterial média inferior a 60mmHg (54±9.6 mmHg) após indução anestésica; 83% dos cães hipotensos (n=10) necessitaram de fármacos vasoativos para tratamento da hipotensão. Com relação às alterações hemodinâmicas, os pacientes diabéticos submetidos à anestesia geral foram mais propensos à hipotensão arterial que pode ser decorrente da resposta dos animais mais velhos aos fármacos empregados; entretanto essa alteração merece maior investigação.(AU)

Anesthetic complications in diabetic dogs subjected to phacoemulsification / Complicações anestésicas em cães diabéticos submetidos a facoemulsificação

The aim of this paper was to compare the incidence of anesthetic complications in diabetic and nondiabetic dogs subjected to phacoemulsification. In total, 30 male and female dogs of different breeds were used. The dogs were distributed into two groups: diabetic (DG) (n=15) and control (CG) (n=15). The animals were premedicated with acepromazine (0.03mg/kg) and meperidine (4mg/kg), intramuscularly. After 20 minutes, anesthesia was induced with propofol (2 to 5mg/kg) and maintained with isoflurane. The animals were monitored and the heart rate, respiratory rate, peripheral oxyhemoglobin saturation, end tidal carbon dioxide tension, inspired and expired isoflurane fraction, and invasive arterial pressure were recorded at 10 minute intervals during the surgical procedure. Arterial hemogasometry was performed after anesthetic induction (T0) and at the end of the surgical procedure. Diabetic patients (DG 10±2 years) were older than non-diabetic group (CG 6±2 years). The expired isoflurane fraction after induction was 30% higher in the control group (CG 1.3±0.3%, DG 1.0±0.2%) (p<0.01). The most common anesthetic complication was hypotension. In total, 80% of the diabetic animals (n=12) exhibited mean arterial pressure (MAP) lower than 60mmHg (54±9.6mmHg) after anesthetic induction, and 83% of the hypotensive dogs (n=10) required vasoactive drugs to treat hypotension. Regarding hemodynamic changes, diabetic patients subjected to general anesthesia were more likely to exhibit hypotension which may be due to the response of older animals to the drugs used; however, this change deserves further investigation.(AU)

O objetivo do presente estudo foi comparar a incidência de complicações anestésicas em cães diabéticos e não diabéticos submetidos a cirurgia de facoemulsificação. Foram utilizados 30 cães, machos ou fêmeas de diversas raças. Os cães foram distribuídos em dois grupos: diabético (GD) (n=15) e controle (GC) (n=15). Os animais foram pré-tratados com acepromazina (0,03mg/kg) e meperidina (4mg/kg), pela via intramuscular. Após 20 minutos, a indução foi realizada com propofol (2 a 5mg/kg) e a manutenção da anestesia com isofluorano. Os animais foram monitorados e as variáveis de frequência cardíaca, frequência respiratória, saturação oxihemoglobina periférica, concentração dióxido de carbono no final da expiração, fração inspirada e expirada de isofluorano e pressão arterial invasiva, foram registradas em intervalos de 10 minutos durante o procedimento cirúrgico. A hemogasometria arterial foi realizada após a indução (T0) e ao final do procedimento cirúrgico (T40). A idade dos animais do grupo diabético (10±2 anos) foi superior em relação aos animais do grupo controle (6±2 anos) (p<0,0001). A concentração expirada de isofluorano após a indução foi 30% superior nos animais do grupo controle (GC 1,3±0,3%, GD 1,0±0,2%) (p<0,01). A complicação anestésica mais comum foi a hipotensão arterial, 80% dos animais diabéticos (n=12) apresentaram pressão arterial média inferior a 60mmHg (54±9.6 mmHg) após indução anestésica; 83% dos cães hipotensos (n=10) necessitaram de fármacos vasoativos para tratamento da hipotensão. Com relação às alterações hemodinâmicas, os pacientes diabéticos submetidos à anestesia geral foram mais propensos à hipotensão arterial que pode ser decorrente da resposta dos animais mais velhos aos fármacos empregados; entretanto essa alteração merece maior investigação.(AU)

Anesthetic complications in diabetic dogs subjected to phacoemulsification

ABSTRACT: The aim of this paper was to compare the incidence of anesthetic complications in diabetic and nondiabetic dogs subjected to phacoemulsification. In total, 30 male and female dogs of different breeds were used. The dogs were distributed into two groups: diabetic (DG) (n=15) and control (CG) (n=15). The animals were premedicated with acepromazine (0.03mg/kg) and meperidine (4mg/kg), intramuscularly. After 20 minutes, anesthesia was induced with propofol (2 to 5mg/kg) and maintained with isoflurane. The animals were monitored and the heart rate, respiratory rate, peripheral oxyhemoglobin saturation, end tidal carbon dioxide tension, inspired and expired isoflurane fraction, and invasive arterial pressure were recorded at 10 minute intervals during the surgical procedure. Arterial hemogasometry was performed after anesthetic induction (T0) and at the end of the surgical procedure. Diabetic patients (DG 10±2 years) were older than non-diabetic group (CG 6±2 years). The expired isoflurane fraction after induction was 30% higher in the control group (CG 1.3±0.3%, DG 1.0±0.2%) (p 0.01). The most common anesthetic complication was hypotension. In total, 80% of the diabetic animals (n=12) exhibited mean arterial pressure (MAP) lower than 60mmHg (54±9.6mmHg) after anesthetic induction, and 83% of the hypotensive dogs (n=10) required vasoactive drugs to treat hypotension. Regarding hemodynamic changes, diabetic patients subjected to general anesthesia were more likely to exhibit hypotension which may be due to the response of older animals to the drugs used; however, this change deserves further investigation.

RESUMO: O objetivo do presente estudo foi comparar a incidência de complicações anestésicas em cães diabéticos e não diabéticos submetidos a cirurgia de facoemulsificação. Foram utilizados 30 cães, machos ou fêmeas de diversas raças. Os cães foram distribuídos em dois grupos: diabético (GD) (n=15) e controle (GC) (n=15). Os animais foram pré-tratados com acepromazina (0,03mg/kg) e meperidina (4mg/kg), pela via intramuscular. Após 20 minutos, a indução foi realizada com propofol (2 a 5mg/kg) e a manutenção da anestesia com isofluorano. Os animais foram monitorados e as variáveis de frequência cardíaca, frequência respiratória, saturação oxihemoglobina periférica, concentração dióxido de carbono no final da expiração, fração inspirada e expirada de isofluorano e pressão arterial invasiva, foram registradas em intervalos de 10 minutos durante o procedimento cirúrgico. A hemogasometria arterial foi realizada após a indução (T0) e ao final do procedimento cirúrgico (T40). A idade dos animais do grupo diabético (10±2 anos) foi superior em relação aos animais do grupo controle (6±2 anos) (p 0,0001). A concentração expirada de isofluorano após a indução foi 30% superior nos animais do grupo controle (GC 1,3±0,3%, GD 1,0±0,2%) (p 0,01). A complicação anestésica mais comum foi a hipotensão arterial, 80% dos animais diabéticos (n=12) apresentaram pressão arterial média inferior a 60mmHg (54±9.6 mmHg) após indução anestésica; 83% dos cães hipotensos (n=10) necessitaram de fármacos vasoativos para tratamento da hipotensão. Com relação às alterações hemodinâmicas, os pacientes diabéticos submetidos à anestesia geral foram mais propensos à hipotensão arterial que pode ser decorrente da resposta dos animais mais velhos aos fármacos empregados; entretanto essa alteração merece maior investigação.

Isolation and biochemical characterization of bradykinin-potentiating peptides from Bitis gabonica rhinoceros

Background: Venoms represent a still underexplored reservoir of bioactive components that might mitigate or cure diseases in conditions in which conventional therapy is ineffective. The bradykinin-potentiating peptides (BPPs) comprise a class of angiotensin-I converting enzyme (ACE) inhibitors. The BPPs usually consist of oligopeptides with 5 to 13 residues with a high number of proline residues and the tripeptide Ile-Pro-Pro (IPP-tripeptide) in the C-terminus region and have a conserved N-terminal pyroglutamate residue. As a whole, the action of the BPPs on prey and snakebite victims results in the decrease of the blood pressure. The aim of this work was to isolate and characterize novel BPPs from the venom of Bitis gabonica rhinoceros. Methods: The crude venom of B. g. rhinoceros was fractionated by size exclusion chromatography and the peptide fraction (<7 kDa) was separated by reverse phase chromatography (RP-HPLC) and analyzed by ESI-IT-TOF-MS/MS. One new BPP was identified, synthetized and assayed for ACE inhibition and, in vivo, for edema potentiation. Results: Typical BPP signatures were identified in three RP-HPLC fractions. CID fragmentation presented the usual y-ion of the terminal P-P fragment as a predominant signal at m/z 213.1. De novo peptide sequencing identified one Bothrops-like BPP and one new BPP sequence. The new BPP was synthesized and showed poor inhibition over ACE, but displayed significant bradykinin-induced edema potentiation. Conclusions: So far, few BPPs are described in Viperinae, and based on the sequenced peptides, two non-canonical sequences were detected. The possible clinical role of this new peptides remains unclear.(AU)

Isolation and biochemical characterization of bradykinin-potentiating peptides from Bitis gabonica rhinoceros

Background: Venoms represent a still underexplored reservoir of bioactive components that might mitigate or cure diseases in conditions in which conventional therapy is ineffective. The bradykinin-potentiating peptides (BPPs) comprise a class of angiotensin-I converting enzyme (ACE) inhibitors. The BPPs usually consist of oligopeptides with 5 to 13 residues with a high number of proline residues and the tripeptide Ile-Pro-Pro (IPP-tripeptide) in the C-terminus region and have a conserved N-terminal pyroglutamate residue. As a whole, the action of the BPPs on prey and snakebite victims results in the decrease of the blood pressure. The aim of this work was to isolate and characterize novel BPPs from the venom of Bitis gabonica rhinoceros. Methods: The crude venom of B. g. rhinoceros was fractionated by size exclusion chromatography and the peptide fraction (<7 kDa) was separated by reverse phase chromatography (RP-HPLC) and analyzed by ESI-IT-TOF-MS/MS. One new BPP was identified, synthetized and assayed for ACE inhibition and, in vivo, for edema potentiation. Results: Typical BPP signatures were identified in three RP-HPLC fractions. CID fragmentation presented the usual y-ion of the terminal P-P fragment as a predominant signal at m/z 213.1. De novo peptide sequencing identified one Bothrops-like BPP and one new BPP sequence. The new BPP was synthesized and showed poor inhibition over ACE, but displayed significant bradykinin-induced edema potentiation. Conclusions: So far, few BPPs are described in Viperinae, and based on the sequenced peptides, two non-canonical sequences were detected. The possible clinical role of this new peptides remains unclear.(AU)

Isolation and biochemical characterization of bradykinin-potentiating peptides from Bitis gabonica rhinoceros

Abstract Background: Venoms represent a still underexplored reservoir of bioactive components that might mitigate or cure diseases in conditions in which conventional therapy is ineffective. The bradykinin-potentiating peptides (BPPs) comprise a class of angiotensin-I converting enzyme (ACE) inhibitors. The BPPs usually consist of oligopeptides with 5 to 13 residues with a high number of proline residues and the tripeptide Ile-Pro-Pro (IPP-tripeptide) in the C-terminus region and have a conserved N-terminal pyroglutamate residue. As a whole, the action of the BPPs on prey and snakebite victims results in the decrease of the blood pressure. The aim of this work was to isolate and characterize novel BPPs from the venom of Bitis gabonica rhinoceros. Methods: The crude venom of B. g. rhinoceros was fractionated by size exclusion chromatography and the peptide fraction ( 7 kDa) was separated by reverse phase chromatography (RP-HPLC) and analyzed by ESI-IT-TOF-MS/MS. One new BPP was identified, synthetized and assayed for ACE inhibition and, in vivo, for edema potentiation. Results: Typical BPP signatures were identified in three RP-HPLC fractions. CID fragmentation presented the usual y-ion of the terminal P-P fragment as a predominant signal at m/z 213.1. De novo peptide sequencing identified one Bothrops-like BPP and one new BPP sequence. The new BPP was synthesized and showed poor inhibition over ACE, but displayed significant bradykinin-induced edema potentiation. Conclusions: So far, few BPPs are described in Viperinae, and based on the sequenced peptides, two non-canonical sequences were detected. The possible clinical role of this new peptides remains unclear.

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 g/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 th

Pharmacological evaluation of the hydro-alcoholic extract of Campomanesia phaea fruits in rats

Abstract Campomanesia phaea (Myrtaceae), popularly known as cambuci, is one of several species of plants producing comestible fruits, largely used in human nutrition. Despite its consumption and economic potential, limited scientific research is available on the Campomanesia, especially those related to its therapeutic benefits. It is reported by traditional medicine the use of the plant in the treatment of different disorders, such as cardiovascular and nervous system disturbances. So, the aim of this study was to carry out the pharmacological evaluation of the hydro-alcoholic extract (HAE) of Campomanesia fruits in rats by screening consisting of tests: a) neuropharmacological observation, b) test on the cardiovascular system. The HAE, prepared from the extraction of fruits with water/ethanol, was concentrated and freeze-dried. Behavioral responses in rats were investigated in open field test and the cardiovascular actions were investigated by a register of indirect blood pressure and the register of spontaneous beating rate right atrium. The results revealed that HAE induced grooming, hypotension and bradycardia. So, this study identified an action on the central nervous system, represented by grooming, and a cardiovascular activity of Campomanesia. The hypotension, attributed in part to bradycardia, was not related to a cholinergic effect, discarding a possible cholinomimetic action of the plant that could justify both cardiovascular and central actions.

Resumo Campomanesia phaea (Myrtaceae), popularmente conhecida como cambuci, é uma das várias espécies de plantas que produzem frutos comestíveis amplamente utilizados na nutrição humana. Apesar de seu consumo e potencial econômico, há poucas pesquisas científicas sobre a Campomanesia, especialmente aquelas relacionadas aos seus benefícios terapêuticos. É relatado pela medicina tradicional o uso da planta no tratamento de diferentes distúrbios, tais como distúrbios do sistema nervoso e cardiovascular. Assim, o objetivo deste estudo foi realizar a avaliação farmacológica do extrato hidroalcoólico (EHA) dos frutos de Campomanesia phaea em ratos através de triagem composta pelos testes: a) observação neurofarmacológica, b) testes no sistema cardiovascular. O EHA, preparado a partir da extração de frutos com água/etanol, foi concentrado e liofilizado. As respostas comportamentais em ratos foram investigadas em teste de campo aberto e as ações cardiovasculares foram investigadas pelo registro da pressão arterial indireta e o registro da taxa de batimentos cardíacos espontâneos em preparações isoladas de átrio direito. Os resultados revelaram que EHA induziu grooming, hipotensão e bradicardia. Assim, este estudo identificou uma ação da Campomanesia sobre o sistema nervoso central, representada por grooming, e uma atividade cardiovascular. A hipotensão, atribuída em parte à bradicardia, não está relacionada a um efeito colinérgico, descartando uma possível ação colinomimética da planta que pudesse justificar tanto as ações cardiovasculares quanto as centrais.

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); […]

Cardiac index by thermodilution or transthoracic echocardiography in dogs at different hemodynamic states / Índice cardíaco pelos métodos de termodiluição ou ecocardiografia transtorácica em cães sob diferentes situações hemodinâmicas

Proper monitoring of cardiac index (CI) in critically ill patients requires accurate and minimally invasive methods. The aim of this study was to compare the CI values obtained by thermodilution or echocardiography using different methods in dogs in different hemodynamic states. Nine dogs weighing 19.6±1.3kg were anesthetized with isoflurane at 1.4V% (Baseline) and subjected to mechanical ventilation (MV),a hypodynamic state (Hypo) with isoflurane at 3.5V% and hyperdynamic state (hyper) with dobutamine infusion at 5gkg-1min-1. CI analysis was performed by thermodilution (TD) and using the modified Simpson's method, aortic velocity-time integral (A-VTI) method and pulmonary VTI (P-VTI) method. We performed Pearson's correlation and Bland-Altman analysis. The CI values (Lm-2min-1) of the animals in the Baseline, MV, Hypo and Hyper states were 4.3±1, 3.6±0.7, 2.9±0.66 and 6.1±2, for TD; 2.8±0.7, 2.4±0.3, 1.7±0.7 and 4.4±1.2, for Simpson's method; 3.4±0.9, 3.1±0.7, 2.6±3.4, 6.1±1.8 for A-VTI; and 3.6±0.8, 3.6±0.8, 2.7±0.6 and 6.2±1.5, for P-VTI. The CI values using Simpson's method were lower than those obtained by TD in all states, and it was observed a significant correlation in the Hypo (r=0.89) and Hyper (r=0.76) groups. In addition,the percent error in the Hypo group using Simpson's method was 26% relative to TD, which allowed for the identification of the different hemodynamic states. With respect to the other methods and states, there was no agreement or correlation between the methods and TD. We concluded that none of the tested echocardiography methods exhibited acceptable agreement with thermodilution at different hemodynamic states.(AU)

A adequada monitoração do índice cardíaco (IC) em pacientes críticos requer métodos acurados e minimamente invasivos. O objetivo deste estudo foi comparar o IC obtido por termodiluição ou ecocardiografia em cães sob alterações hemodinâmicas. Utilizaram-se nove cães pesando 19,6±1,3kg, os quais foram anestesiados com isofluoranoa1,4V% (Basal) e submetidos à ventilação mecânica (VM) e estados hipodinâmico (Hipo) com isofluoranoa3,5V% e hiperdinâmico (Hiper), com dobutaminaa5µgkg-1min-1. O IC foi obtido por termodiluição (TD) e pelos métodos ecocardiográficos de Simpson modificado, e pela velocidade em tempo integral (VTI) nas valvas aórtica (VTI-A) e pulmonar (VTI-P). Realizou-se a análise de correlação de Pearson e de concordância de Bland-Altman. O IC (Lm-2min-1) nas fases Basal, VM, Hipo e Hiper foi de 4,3±1, 3,6±0,7, 2,9±0,66 e 6,1±2 para TD; 2,8 ±0,7, 2,4±0,3, 1,7±0,7 e 4,4±1,2 para Simpson; 3,4±0,9, 3,1 ±0,7, 2,6±3,4, 6,1±1,8 para VTI-A e 3,6±0,8, 3,6±0,8, 2,7±0,6 e 6,2±1,5 para VTI-P. O método de Simpson foi menor que a TD em todas as fases, mas com correlação significativa nos estados Hipo (r=0,89) e Hiper (r=0,76) e percentagem de erro de 26% no Hipo em relação à TD, identificando os diferentes estados hemodinâmicos. Nos demais, não houve concordância ou correlação com a TD. Conclui-se que nenhum dos métodos testados apresentou concordância aceitável com a termodiluição nos diferentes estados hemodinâmicos.(AU)

BIOQUÍMICA SÉRICA, TERMOGRAFIA E BIÓPSIA MUSCULAR COMO MÉTODOS DE DIAGNÓSTICO DE MIOPATIA PÓS-ANESTÉSICA EM EQUINOS SUBMETIDOS À ANESTESIA GERAL

A espécie equina possui um maior risco de desenvolver uma grande variedade de complicações anestésicas e associadas ao procedimento, em comparação a outras espécies. Idealmente, a pressão arterial sistêmica média (PAM) deve ser mantida acima de 80 mmHg e a pressão abaixo de 70 mmHg deve ser tratada. O presente trabalho teve como objetivo realizar uma revisão de literatura sobre miopatia pósanestésica (MPA) e em seguida descrever a avaliação de miopatia pós-anestésica através de diferentes métodos de diagnóstico, realizados experimentalmente em equinos saudáveis. Os grupamentos musculares que serão mais afetados na MPA dependem do decúbito do animal, mas de forma geral, os músculos em contato com a superfície são os mais afetados. O diagnóstico é baseado, inicialmente, em sinais clínicos, mas diferentes exames complementares podem ser utilizados. No presente estudo avaliou-se 7 animais, que foram submetidos à anestesia geral, sendo eles divididos em dois grupos, um com PAM mantida em 60 mmHg e outro em 70 mmHg. Realizou-se exames como bioquímico sérico, termografia e biópsia muscular para comparar os resultados entre os grupos e verificar se houve desenvolvimento de (MPA). Após analisar os resultados, foi possível observar que nenhum animal apresentou aumento das enzimas musculares (CK, AST e LDH) em níveis que sugerissem MPA, além disso não houve diferença significativa entre os grupos. Da mesma forma ocorreu com a termografia do glúteo. Quanto à microscopia óptica da amostra muscular, não foram observadas alterações nos animais em nenhum dos grupos. Com isso, podemos concluir que no estudo não houve diferenças entre os grupos, mas sugere-se um estudo maior, devido ao baixo número de animais utilizados.

Equine has a higher risk of developing a wide variety of anesthetic and procedure-related complications, compared to other species. Ideally, mean systemic arterial pressure should be maintained above 80 mmHg and pressure below 70 mmHg should be treated. The present study aimed to conduct a literature review about postanesthetic myopathy and then describe the evaluation of post-anesthetic myopathy through different diagnostic methods, performed experimentally in healthy horses. The muscle groups that will be most affected depend on the animal recumbency, but in general, the muscles in contact with the surface are the most affected. The diagnosis is based, initially, on clinical signs, but complementary exams can be used. In the present study, 7 animals were evaluated and submitted to general anesthesia, divided into two groups, one with mean arterial pressure maintained at 60 mmHg and the other at 70 mmHg. Examinations such as serum biochemistry, thermography and muscle biopsy were performed to compare the results between groups and to verify whether there was development of the disturb. After analyzing the results, it was possible to observe that no animal showed an increase in muscle enzymes (CK, AST and LDH) at levels that suggested post-anesthetic myopathy, and there was no significant difference between groups. The same happened with the gluteal thermography. As for the optical microscopy of the muscle sample, there were no alterations in the animals in any of the groups. With that, we can conclude that in the study there were no differences between the groups, but a larger study is suggested, due to the low number of animals used.

Calorimetria indireta na monitoração hemodinâmica e metabólica em cães sob diferentes situações hemodinâmicas / Indirect calorimetry in hemodinamic and metabolic monitoring in dogs under different hemodynamic states

A monitoração do estado hemodinâmico visa ao equilíbrio entre a oferta e a demanda de oxigênio tecidual. O objetivo deste estudo foi avaliar a utilização da calorimetria indireta (CI) frente à termodiluição (TD) em cães sob diferentes estados hemodinâmicos. Utilizaram-se nove cães pesando 19,6±1,3kg, os quais foram anestesiados com isofluorano a 1,4V% (Basal), submetidos à ventilação mecânica (VM) e estados hipodinâmico (Hipo), com isofluorano a 3,5V%, e hiperdinâmico (Hiper), com dobutamina a 5µg/kg/min. Utilizou-se um cateter de Swan-Ganz para aferição do índice cardíaco (IC) por TD, cálculo do consumo de oxigênio pelo método de Fick (VO2Fick) e para coleta de sangue venoso central e misto. Com a CI, obtiveram-se os valores de consumo de oxigênio (VO2), produção de CO2(VCO2) e expirado de CO2 (EtCO2). Para a determinação do IC por CI, utilizou-se o princípio de Fick com os valores de VO2 e os sangues arteriais e venosos misto (Fickmix) ou central (Fickvc), e pela relação dos valores de VCO2 e EtCO2(FickCO2). A análise estatística compreendeu os testes de Dunnet, para diferença entre as fases, e Tukey, para diferenças entre os métodos (P≤0,05). Foram realizadas as análises de correlação de Pearson e de concordância de Bland-Altman. A CI forneceu valores de VO230 a 40% maiores que VO2Fick, mas identificou a redução no VO2 após a VM e Hipo, o que não ocorreu com VO2Fick. Os valores de VCO2diminuíram nas fases VM e Hipo. Houve redução do IC na fase Hipo com todos os métodos e aumento na fase Hiper com TD e Fickvc. Os valores de IC pelos métodos de Fickmixe Fickvc foram maiores que TD em todos os momentos, e FickCO2foi menor que TD na fase Hiper. Nenhum dos métodos apresentou concordância e correlação com a TD. Conclui-se que a CI pode ser utilizada na mensuração do VO2 e VCO2 de cães sob diferentes estados hemodinâmicos. Contudo, embora seja possível a identificação dos diferentes estados hemodinâmicos, os valores de IC não podem ser comparados à termodiluição.(AU)

Monitoring the hemodynamic state seeks a balance between the supply and demand of oxygen by tissues. The aim of this study was to evaluate the use of indirect calorimetry (IC) compared to thermodilution (TD) in dogs under different hemodynamic states. Nine dogs weighing 19.6±1.3kg were anesthetized with isoflurane at 1.4 V% (Baseline) and subjected to mechanical ventilation (MV), a hypodynamic state (Hypo) with isoflurane at 3.5V% and hyperdynamic state (Hyper) with dobutamine infusion at 5μg/kg/min. We used a Swan-Ganz catheter for measurement of cardiac index (CI) by TD, calculation of oxygen consumption by Fick's method (VO2Fick) and to collect central and mixed venous blood. With the IC we obtained oxygen consumption (VO2), CO2 production (VCO2) and end tidal CO2(EtCO2). For the determination of CI by IC we used the Fick's principle with VO2values, and arterial and mixed venous blood (Fickmix)or arterial and central venous blood (Fickvc); and by the ratio of the values of VCO2 and EtCO2(FickCO2). We performed the statistical analysis by Dunnet tests, for the difference between the states, and Tukey for differences between methods (P≤0.05). Pearson correlation and Bland-Altman analysis was performed for correlation and agreement analysis. IC provided VO2values 30 to 40% higher than the VO2Fick but identified the reduction in VO2after VM and Hypo, which did not occur with VO2Fick. The VCO2 values decreased in VM and Hypo. CI values decreased in Hypo with all methods and increase in Hyper with TD and Fickvc. The CI values for Fickmix and Fickvc were greater than TD at all times and FickCO2 was lower than TD in the Hyper. None of the methods presented agreement and correlation with TD. Thus, indirect calorimetry can be used to measure the VO2 and VCO2 in dogs in different hemodynamic states. However, although it is possible to identify the hemodynamic status, cardiac index values cannot be compared to thermodilution.(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)