The objective of this study was to evaluate the effects of three different associations: acepromazine 0,1mg/kg, alfentanil 0,05mg/kg and propofol 6,0mg/kg (Group l); acepromazine 0,1mg/kg, 0,9% NaCI 0,05ml/kg and propofol 6,0mg/kg (Group II); 0,9% NaCI 0,1ml/kg, alfentanil 0,05mg/kg and propofol 6,0mg/kg (Group III). Thirty healthy adult mongrel dogs (10 males and 20 females; mean weight, 14,44 ± 2,72kg) were divided in three groups randomiy assigned to one of the associations. Short-term bradicardia was observed in groups I and III immediately after the administration of alfentanil. The heart rate retumed to control values at the end of the evaluation period. AU the anesthetic procedures caused severe alterations in respiratory function with a significant decrease in PaO2, pH and SaO2 and rise of PaCO2. Respiratory depression was more intense when alfentanil was used. Respiratory rate with this drug increased significantiy. In the acepromazine-propofol group, the some alterations could be noticed but not so severe. The induction of anesthesia in all groups was uneventful and excitement free and the intubation was easily performed. Anesthesia recovery was smooth, fast and excitment free. These observations confirm that propofol is in fact an effective and safe induction agent once we did not observe life-threatining cardiovascular depression and undesirable side effects. Both acepromazine alone and acepromazine pius alfentanil are effective premedication agents once they contributed to an uneventful induction and recovery of anesthesia without excitatory fenômeno or myoclonus, with prolongation of the anesthetic time of propofol.
propofol; acepromazine; alfentanil; dogs; anesthesia
