A comparison of cardiopulmonary and anesthetic effects of an induction dose of alfaxalone or propofol in dogs.

摘要

Objective: To compare the physiological parameters, arterial blood gas values, induction quality, and recovery quality after IV injection of alfaxalone or propofol in dogs. Study design: Prospective, randomized, blinded crossover. Animals: Eight random-source adult female mixed-breed dogs weighing 18.7+or-4.5 kg. Methods: Dogs were assigned to receive up to 8 mg kg-1 propofol or 4 mg kg-1 alfaxalone, administered to effect, at 10% of the calculated dose every 10 seconds. They then received the alternate drug after a 6-day washout. Temperature, pulse rate, respiratory rate, direct blood pressure, and arterial blood gases were measured before induction, immediately post-induction, and at 5-minute intervals until extubation. Quality of induction, recovery, and ataxia were scored by a single blinded investigator. Duration of anesthesia and recovery, and adverse events were recorded. Results: The mean doses required for induction were 2.6+or-0.4 mg kg-1 alfaxalone and 5.2+or-0.8 mg kg-1 propofol. After alfaxalone, temperature, respiration, and pH were significantly lower, and PaCO₂ significantly higher post-induction compared to baseline (p<0.03). After propofol, pH, PaO₂, and SaO₂ were significantly lower, and PaCO₂, HCO₃, and PA-aO₂ gradient significantly higher post-induction compared to baseline (p<0.03). Post-induction and 5-minute physiologic and blood gas values were not significantly different between alfaxalone and propofol. Alfaxalone resulted in significantly longer times to achieve sternal recumbency (p=0.0003) and standing (p=0.0004) compared to propofol. Subjective scores for induction, recovery, and ataxia were not significantly different between treatments; however, dogs undergoing alfaxalone anesthesia were more likely to have >=1 adverse event (p=0.041). There were no serious adverse events in either treatment. Conclusions and clinical relevance: There were no clinically significant differences in cardiopulmonary effects between propofol and alfaxalone. A single bolus of propofol resulted in shorter recovery times and fewer adverse events than a single bolus of alfaxalone.