Induction and Intubation Effects on Hemodynamic Response Using Slow Propofol or Ketamine- Slow Propofol Infusion in Dogs: An Experimental Study

Propofol is widely used in anesthetic induction in both human and veterinary medicine. However, it has hemodynamic adverse effects such as hypotension and bradycardia, particularly at rapid infusion rate. This study aimed to attenuate the hemodynamic changes during induction and investigate the hemodynamic response to tracheal intubation using slow propofol or ketamine- slow propofol infusion in dogs. Eight dogs were assigned to two groups: Group1 received intravenous slow propofol 1 mg/kg/min for anesthesia induction and Group2 received intravenous ketamine bolus 2 mg/kg prior to slow propofol 1 mg/kg/min for anesthetic induction. The propofol infusion rate continued until achieving the appropriate conditions for intubation. Heart rate and arterial blood pressure were measured 30 minutes after premedication (baseline), one minute after induction and intubation. The results showed that the propofol dose required for induction and intubation was significantly lower in Group 2 (1.55±0.37 mg/kg) than Group1 (3.56±0.44 mg/kg), with P = 0.01. After induction, Group 2 exhibited a sharp increase in heart rate (96.2 ±2.72a) compared to Group1 (60 ± 3.14c) with P < 0.001. Both groups showed non-significant changes in arterial blood pressure after induction. Meanwhile, Group 1 showed more variability and less stability in response to intubation. Also, it exhibited more significant fluctuations in systolic, diastolic and mean arterial blood pressure levels after intubation. Group 2 maintained greater stability in arterial blood pressure in response to tracheal intubation. In conclusion and from the obtained results, slow propofol or ketamine- slow propofol combination were effective in mitigating hemodynamic fluctuations following induction. However, the ketamine-slow propofol combination achieved better stability in arterial pressure post-intubation than slow propofol alone.