Comparison of atracurium and vecuronium as muscle relaxants for ocular and orthopaedic interventions in dogs

Twenty adult dogs of either sex, divided into 2 equal groups were used for evaluation of atracurium (0.5 mg/kg IV) and vecuronium (0.1 mg/kg IV) in atropine-butorphanol-diazepam premedicated and propofol (till effect IV) induced dogs which were further maintained on isoflurane with controlled IPPV mode of the ventilator for positive pressure ventilation. A total of 13 ophthalmic and 7 orthopaedic interventions were done in both the groups. Pulmonary parameters were measured at baseline (pre-operative), just after induction and at 5, 15, 30 and 45 minutes after the administration of NMBA and the recovery parameters were recorded after weaning from the anaesthetic gas. The eyeballs deviated to the ventro-medial position after the induction with diazepam and propofol and resumed the central position within 30 seconds of atracurium or vecuronium administration thus, proving highly beneficial for the eye globe and corneal interventions. On a comparative basis, atracurium and vecuronium provided muscle relaxation for 40.1 ± 4.71 and 37.7 ± 1.01 minutes respectively. Uniform and pronounced muscle relaxation along with excellent sedation was found in both the groups. All pulmonary parameters remained within normal range. Following discontinuation of the isoflurane, the time taken to bear weight was 38.88 ± 1.45 and 39.63 ± 4.08 minutes in the atracurium and vecuronium groups respectively.