Propofol or thiopentone as induction agents in romifidine-sedated and halothane-N2O-anesthetized dogs: a preliminary study

The objective of this paper was to evaluate the use of romifidine as a prem edicant in dogs before general anesthesia induced with propofol or thiopent one and maintained with halothane-N2O. Fifteen healthy dogs were anesthetiz ed twice. Each dog received, as preanesthetic protocol, atropine (10 mu g/k g, IM) and romifidine (40 mu g/kg, IM); induction was delivered with propof ol or thiopentone and anesthesia was maintained with halothane and N2O for 1 h. Some cardiovascular and respiratory variables and recovery rimes were recorded. Induction doses of propofol or thiopentone and the percentage of halothane necessary for maintaining anesthesia were also registered. Thiope ntone as an induction agent is more respiratory depressive but is less hypo tensive than propofol. Thiopentone reduces further the percentage of haloth ane necessary for maintaining the anesthesia. However, the quality of recov ery is poorer, as the time to extubation is longer and the dogs occasionall y had a violent recovery. The combination of romifidine, atropine, propofol , halothane, and N2O appears to be an effective combination for inducing an d maintaining general anesthesia in healthy dogs.