Sevoflurane face mask anesthesia in rabbits - A comparison of 3 % sevoflurane with 3 % halothane

Sevoflurane is a rapid-acting, potent, volatile anesthetic which is widely used in the clinical field. The anesthetic shows rapid uptake and elimination due to a low blood:gas partition coefficient. In this study, we tested the efficacy of sevoflurane anesthesia with a face mask in rabbit anesthesia. Five adult SPF New Zealand white rabbits were induced and maintained with 3% sevoflurane and 3% halothane using a face mask. Physiologic conditions were evaluated according to body temperature, heart rate, respiratory rate, blood pressure and blood gas changes. The induction and recovery times were recorded. The depth of anesthesia was monitored with righting, withdrawal and palpebral reflexes of the rabbits. The induction time of anesthesia, estimated by the time from the commencement of gas inhalation to the loss of muscle tone was significantly shorter (101 +/- 19 seconds) in sevoflurane than in halothane (135 +/- 16 seconds). The recovery time from sevoflurane anesthesia, divided into three stages, alert stage (179 +/- 85 seconds), sitting stage (301 +/- 141 seconds) and walking stage (360 +/- 126 seconds) was significantly shorter than that from halothane anesthesia. The depth of anesthesia was lighter than the plane 3 at stage 3 during both halothane and sevoflurane anesthesia. Respiratory rate was well maintained in both halothane and sevoflurane anesthesia. Blood pressure, particularly systolic pressure, was decreased by halothane but less significant by sevoflurane. Blood gas analysis showed no diversities between the two anesthetics. We conclude that a face mask anesthesia with sevoflurane is a useful anesthetic method for rabbits.