Constant rate infusion of propofol for maintenance of anaesthesia in horses

The study was conducted to evaluate propofol as constant rate infusion (CRI) after 2 different preanaesthetic regimens in horses in three clinically healthy experimental female horses as well as on clinical cases in A and B groups. All horses were premedicated with acepromazine (0.02 mg/kg) and xylazine (0.5 mg/kg) i.v. in A group, and xylazine (0.5 mg/kg) and diazepam (0.1mg/kg) i.v. in B group. Induction of anaesthesia was achieved by i.v. administration of xylazine and ketamine in ratio of 3:5 by weight, till effect in both groups. Anaesthesia was maintained by CRI of 1% propofol for 30 min. Anaesthetic and physiological parameters were recorded. Significantly lesser doses of xylazine and ketamine for induction of anaesthesia was required in B group as compared to A group. Amount of propofol required to maintain the adequate depth of anaesthesia in B group was also lesser in comparison to A group. B group also produced less depression of cardiopulmonary system with good to excellent quality of recovery from anaesthesia. Standing time in animals of A group was comparatively lesser than B group. Results on present study on the various anaesthetic and physiological (HR, RR, RT, MAP, SpO₂) parameters did not reveal deleterious effects on any vital functions and organs in the body and these drug regimens can safely be used in routine clinical cases of surgery in field conditions without any risk.