ELECTROCARDIOGRAPHY IN DOGS ANESTHETIZED WITH DESFLURANE DILUTED IN EITHER INTERMEDIATE OR LOW FLOW OXYGEN. / ELETROCARDIOGRAFIA EM CÃES SUBMETIDOS À ANESTESIA PELO DESFLUORANO COM FLUXO BAIXO OU INTERMEDIÁRIO DE OXIGÊNIO.

ABSTRACT

Desflurane anesthesia in low or intermediate oxygen flow rates were compared in dogs regarding its effects on heart rate (HR) and electrocardiography (ECG). In this experiment, 26 adult healthy mongrel dogs, males and females, weighing 32.04 ± 4.0 kg, were used. Dogs were randomly assigned to two equal groups (G1 and G2). In both groups, general anesthesia was induced with propofol (8.0 ± 2.0 mg/kg IV), followed by inhalation anesthesia with desflurane (7.2V% expired), diluted in oxygen (O2) at a flow rate of 50 mL/kg/min, using a semi-closed anesthetic system. After 15 35 minutes, O2 flow was decreased to 7 mL/kg/min and 30 mL/kg/min for G1 and G2 animals, respectively. After reducing O2 flow rate, the pop-off valve was closed for G1 animals, resulting in a closed anesthetic circuit. Parameters were measured immediately before the drugs were given (M0) and 15 minutes after anesthetic induction (M15), with repeated data collection at 15-minute intervals (M30 to M60). Statistical analysis was performed by Profile Analysis (p£0.05). We concluded that low flow anesthesia does not cause threatening changes in heart rate or in electrocardiographic parameters. KEY-WORDS Anesthesia. Dogs. Desflurane. Low flow. Electrocardiography.