Ciência Rural (Apr 2007)
Hemogasometria e variáveis cardiopulmonares após administração do butorfanol em cães anestesiados pelo desfluorano sob ventilação espontânea Acid-base and cardiopulmonary effects after butorphanol administration in spontaneously breathing dogs anesthetized by desflurane
Abstract
Este experimento teve por objetivos avaliar as possíveis alterações cardiopulmonares e hemogasométricas decorrentes do uso do butorfanol em cães submetidos à anestesia pelo desfluorano sob ventilação espontânea. Para tal, foram utilizados vinte cães adultos, clinicamente saudáveis, pesando 12±3kg. Os animais foram distribuídos igualmente em dois grupos, GS e GB, e induzidos à anestesia com propofol (8,4±0,8mg kg-1, IV), intubados e submetidos à anestesia inalatória pelo desfluorano (10V%). Decorridos 40 minutos da indução, foi administrado aos animais do GS 0,05mL kg-1 de solução fisiológica a 0,9% (salina), enquanto que, no GB, foi aplicado butorfanol na dose de 0,4mg kg-1, ambos pela via intramuscular. As observações das variáveis freqüências cardíaca (FC) e respiratória (f), pressões arteriais sistólica (PAS), diastólica (PAD) e média (PAM), pH arterial (pH), pressão parcial de oxigênio no sangue arterial (PaO2), pressão parcial de dióxido de carbono no sangue arterial (PaCO2), déficit de base (DB), bicarbonato (HCO3) e saturação de oxigênio na hemoglobina (SatO2) tiveram início imediatamente antes da aplicação do opióide ou salina (M0). Novas mensurações foram realizadas 15 minutos após a administração do butorfanol ou salina (M15) e as demais colheitas foram realizadas a intervalos de 15 minutos, por um período de 60 minutos (M30, M45, M60 e M75). Os dados numéricos dessas variáveis foram submetidos à Análise de Perfil (PThe cardiopulmonary and acid-base effects of butorphanol in desflurane anesthetized dogs breathing spontaneously were evaluated. Twenty adult healthy, male and female dogs were used. They were separated into two groups of 10 animals each (GS and GB). Anesthesia was induced with propofol (8.4±0.8mg kg-1 IV) and maintained with desflurane (10V%). After 40 minutes of induction, the animals from GS received saline solution at 0.9% (0.05mL kg-1) and from GB received butorphanol (0.4mg kg-1), both applied intramuscularly. Heart (HR) and respiratory (RR) rates; systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressures; arterial blood pH (pH), arterial partial pressure of O2 (PaO2) and arterial partial pressure of CO2 (PaCO2); base deficit (BD), arterial oxygen saturation (SaO2) and bicarbonate ion concentration (HCO3) were measured. The measurements were taken immediately before the application of the agents (M0). Serial measurements were carried out at 15 minutes intervals after the administration of butorphanol or saline up to 75 minutes (M15, M30, M45, M60 and M75). Data were submitted to Profile Analysis (P<0.05). After butorphanol administration HR, SAP, DAP and MAP decreased significantly. PaO2 had discreet alterations, however without clinical meaning. RR and pH decreased after butorphanol administration while PaCO2 increased significantly. It was possible to conclude that butorphanol administration in desflurane anesthetized dogs produced reduction in the averages of heart rate and arterial pressure and relatively to the respiratory parameters, the opioid produced hypoventilation in spontaneously breathing dogs.
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