Chronotropic effect of propofol or alfaxalone following fentanyl administration in healthy dogs
Article first published online: 16 APR 2014
© 2014 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesia and Analgesia
Veterinary Anaesthesia and Analgesia
Volume 42, Issue 1, pages 88–92, January 2015
How to Cite
Okushima, S., Vettorato, E. and Corletto, F. (2015), Chronotropic effect of propofol or alfaxalone following fentanyl administration in healthy dogs. Veterinary Anaesthesia and Analgesia, 42: 88–92. doi: 10.1111/vaa.12166
- Issue published online: 23 DEC 2014
- Article first published online: 16 APR 2014
- Manuscript Accepted: 21 NOV 2013
- Manuscript Received: 9 AUG 2013
- heart rate;
To compare the effect of alfaxalone and propofol on heart rate (HR) and blood pressure (BP) after fentanyl administration in healthy dogs.
Prospective, randomised clinical study.
Fifty healthy client owned dogs (ASA I/II) requiring general anaesthesia for elective magnetic resonance imaging for neurological conditions.
All dogs received fentanyl 7 μg kg−1 IV and were allocated randomly to receive either alfaxalone (n = 25) or propofol (n = 25) to effect until endotracheal (ET) intubation was possible. Heart rate and oscillometric BP were measured before fentanyl (baseline), after fentanyl (Time F) and after ET intubation (Time GA). Post-induction apnoea were recorded. Data were analysed using Fisher's exact test, Mann Whitney U test and one-way anova for repeated measures as appropriate; p value <0.05 was considered significant.
Dogs receiving propofol showed a greater decrease in HR (−14 beat minute−1, range −47 to 10) compared to alfaxalone (1 beat minute−1, range −33 to 26) (p = 0.0116). Blood pressure decreased over the three time periods with no difference between groups. Incidence of post-induction apnoea was not different between groups.
Following fentanyl administration, anaesthetic induction with propofol resulted in a greater negative chronotropic effect while alfaxalone preserved or increased HR.
Following fentanyl administration, HR decreases more frequently when propofol rather than alfaxalone is used as induction agent. However, given the high individual variability and the small change in predicted HR (−7.7 beats per minute after propofol), the clinical impact arising from choosing propofol or alfaxalone is likely to be small in healthy animals. Further studies in dogs with myocardial disease and altered haemodynamics are warranted.