The effect of ascorbic acid premedication on dexmedetomidine-ketamine anaesthesia was evaluated in five cats in two sets of experiments namely dexmedetomidine-ketamine (control) and ascorbic acid /dexmedetomidine/ketamine (test). The control group involved concurrent intramuscular administration of 10 mg/kg ketamine and 10 µg/kg dexmedetomidine to each cat. Selected anaesthetic indices and vital parameters were recorded at ten minutes' interval for a period of 90 minutes using standard methods. A week later, the test experiment was conducted with the same cats used in the control experiment but the trial was preceded with intramuscular injection of 20 mg/kg ascorbic acid 10 minutes before the concurrent administration of the previously used doses of dexmedetomidine and ketamine. Vitamin C premedication did not produce any significant difference on heart and respiratory rates and rectal temperature of the treated cats. Onset of drug action was not influenced by premedication with vitamin C and was the same in both control and test groups (3.6 ± 1.50 min). The duration of analgesia was also similar for both control (45.6 ± 13.22 min) and test trials (44.4 ± 10.01 min). Ascorbic acid premedication produced a longer duration of anaesthesia (68.2±17.96 min) than the control (59.6 ± 21.51 min). It also produced a significantly (P < 0.05) shorter time to stand (2.2 ± 2.49 min) than the control (4.8 ± 5.34 min). It was concluded that vitamin C intramuscular administration at a dosage of 20mg/kg prior to dexmedetomidine-ketamine anesthesia in cats produced a longer duration of anaesthesia but hastened the time to stand from sternal recumbency.

Total intravenous anaesthesia (TIVA) refers to the induction and maintenance of general anaesthesia with drugs administered solely by the intravenous (IV) route. Presently, ketamine and propofol are popular and in use for TIVA in small animals. This study compared ketamine and propofol anaesthesia in cats premedicated with acepromazine-dexmedetomidine combination. Six indigenous Nigerian local cats were premedicated with intramuscular injection of acepromazine (0.2mg/kg) and dexmedetomidine (40μg/kg) mixture, followed by induction of anesthesia with either bolus propofol (1mg/kg) or ketamine (0.5mg/kg) IV 20 min later. Maintenance of anesthesia for 2h was achieved with continous fl uid administration using dose of 0.5ml/8ml and 0.05ml/8ml in lactated Ringers solution for propofol and ketamine respectively. One week space was allowed between protocols in the crossover experiment. Anesthetic indices, cardiopulmonary parameters, and rectal temperature were recorded at 5 min intervals for 2 h. Duration of anti-nociception with ketamine protocol was not signifi cantly (p.05) different from the corresponding propofol protocol value while recovery time and standing time were signifi cantly (p<.05) different between either protocol. Systolic arterial pressure, Diastolic arterial pressure and mean arterial pressure were signifi cantly (p<0.05) lower for propofol protocol than ketamine protocol, while SpO 2 responses were signifi cantly (p<0.05) higher for propofol protocol than ketamine protocol. There was no statistically signifi cant difference between other physiological variable means recorded for both protocols. It was concluded that ketamine and propofol protocols produced satisfactory anaesthetic induction and maintenance in healthy cats premedicated with acepromazine-dexmedetomidine. Used in the same manner however, Ketamine produces better anaesthetic quality than propofol.