Anesthetic effects of dexmedetomedineketamine sedation followed by isoflurane induction and maintenance in the saker falcon (Falco cherrug)

Background: Avian anesthesia can be challenging due to birds’ anatomical and physiological peculiarities. Also, most drug doses and combinations used are empirical. The objective of this study was to evaluate the anesthetic quality and physiological changes after dexmedetomidine-ketamine sedation and isoflurane anesthesia in the saker falcon (Falco cherrug). Methods: Twelve falcons weighing (mean±standard deviation) 915±175g were included in the study. Pre-sedation heart rate (HR) and respiratory rate (RR) were assessed. A combination of ketamine (3mg/kg) and dexmedetomidine (25µg/kg) was administered intramuscularly. Sedation times were recorded, physiological variables assessed, and various blood parameters measured. Induction was performed with isoflurane at 2% for 2 minutes and anesthesia was maintained at 1%. During maintenance, physiological variables were assessed at 5-minute intervals and blood parameters were re-evaluated before reversal administration. Recovery times were documented. Quality of sedation, maintenance, and recovery were assessed. Results: Sedation was achieved within 2.9±1.0 minutes and quality of sedation and maintenance were deemed «excellent» in all falcons. HR values decreased during sedation (137±38 versus 99±13 beats per minute; p=0.001) and remained constant during maintenance. No significant differences were seen in RR from pre-sedation values. Mean arterial blood pressure (203±14 versus 168±22mmHg; p<0.001) and cloacal temperature (40.3±0.8 versus 38.9±1.0°C; p<0.001) decreased after induction. Hypoxemia (65.9±6.1mmHg) was observed at sedation but resolved during maintenance, while hypercarbia (54.2±11.5mmHg) and acidemia (7.28±0.036) developed. Full recovery was quick (12.3±3.9minutes). Conclusions and clinical relevance: The proposed drug combination provided for high quality sedation, maintenance, and a satisfactory recovery. Nevertheless, alterations in the falcons’ physiology were documented.