Anestesia por infusão contínua de propofol associado ao remifentanil em gatos pré-tratados com acepromazina

• Autor(a) principal: Favarato, Lukiya Silva Campos
• Data de Publicação: 2006
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5083
• topic: Gatos; Anestesia; Remifentanil; Propofol; Cats; Anesthesia; Propofol; Remifentanil; CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA::CLINICA E CIRURGIA ANIMAL::ANESTESIOLOGIA ANIMAL

Propofol is a general anesthetic with desirable characteristics such as ultrashort effect, fast metabolism e low toxicity, which can be used for induction or maintenance of anesthesia. Remifentanil is a recently synthesized opioid, with great analgesic power, ultra-short action and capacity of potentiating general anesthetics. Little information exists on the use of remifentanil in association with propofol in veterinary medicine, particularly in feline species. The objective of the present work was to evaluate the anesthesia by continuous infusion of propofol in association with remifentanil in cats subjected to elective surgeries. A total of 30 cats with indication for orchiectomy and ovariectomy were randomly distributed in three groups of ten animals each, with equal number of males and females. After 6-hour fast for water and 12-hour fast for food, all the animals received 0.1mg/kg of acepromazine by intramuscular route, as preanesthetic medication. After 15 minutes, anesthesia was induced with a propofol bolus of 6 mg/kg. Anesthesia was maintained for 60 minutes by continuous infusion. Group 1 received propofol 0.6 mg/kg/min; Group 2 received propofol 0.4 mg/kg/min in association with remifentanil 0.1 µg/kg/min; and Group 3 received propofol 0.4 mg/kg/min in association with remifentanil 0.2 µg/kg/min. The following variables were evaluated: body temperature, heart frequency, systolic pressure, respiratory frequency, tidal volume, minute ventilation, oxyhemoglobin saturation, hemogasometric values of arterial blood, electrocardiogram, analgesia, muscle relaxantion, eyelid, corneal, interdigital and laryngo-tracheal reflexes, recovery time and capillary filling time. The moments established for variable measurements were: M0 before preanesthetic medication administration; M1 15 minutes after preanesthetic medication; M2 immediately after anesthetic induction and orotracheal intubation; M3 15 minutes after M2, after abdominal wall incision in the females or scrotal incision in the males; M4 30 minutes after M2, at the moment of the ligation of the first ovarian pedicle in the females or of the first spermatic cord in the males; M5 60 minutes after M2, surgery completed. The results allowed the following conclusions: anesthesia by continuous infusion of propofol in association with remifentanil in cats demonstrated to have greater advantages over anesthesia with propofol as the only agent; infusion of remifentanil 0.1 µg/kg/min was better than 0.2 µg/kg/min for providing equivalent analgesia with smaller changes in cardiorespiratory parameters; the increase in analgesia provided by remifentanil 0.1 µg/kg/min and 0,2 0.1 µg/kg/min allowed reduction of approximately 33% in propofol infusion speed; the reduction in the level of hypnosis resulting from the lower propofol dose had no effect on the surgery and allowed a faster anesthetic recovery.