Parâmetros Cardiorrespiratórios e Hematológicos em Cães Anestesiados com Isofluorano e Tramadol, Pré-medicados com Clonidina

Abstract

With this study, the effects of premedication with clonidine over cardiorespiratory and hematimetry in dogs anesthetized with isoflurane and receiving continuous infusion of tramadol, were evaluated. Eight crossbreeding healthy adult dogs, weighting 15,3±3,7kg, provided from Federal University of Pampa kennel, were used. Animals were randomly anesthetized twice with a month interval and allocated in two groups (n=8), Clonidine (CLG) and Control (CG). Animals in CLG received a 5 μg kg -1 bolus of Clonidine diluted in 1mL as premed, while animals in CG received an injection of 1 mL of saline. Anesthesia was acquired with propofol 8 mg kg -1 and maintained with isoflurane (1MAC). After a stabilization period, animals received a bolus of tramadol (2 mg kg -1 ) followed by a continuous rate infusion of 1.5 mg kg -1 h of the same drug. Parameters evaluated were: body temperature (oC), heart rate (HR), respiratory frequency (f), electrocardiography, systolic, diastolic and median arterial blood pressure (SAP, DAP and MAP, respectively), end-tidal carbon dioxide (EtCO 2 ), hemoglobin saturation (SpO 2 ), hematimetric, leucocitary, glucose, lactate, propofol consumption, time of extubation and recovery quality. Data were collected before premed, before induction, before tramadol bolus, and each 10 minutes after CRI was initiated, until a 60 minutes period was achieved. Blood samples were performed before premed, before induction, before tramadol bolus and 30 and 60 minutes after CRI was initiated. Data were evaluated with ANOVA followed by Tukey`s test (p<0.05). It was observed a significant decrease in HR, while other variables showed no differences throughout the experimental period. It was concluded that the association has been shown to be safe for use in healthy animals. Further studies are necessary to determinate if this drug could enhance antinociceptive effect of tramadol in dogs.