Sedative, analgesic and cardiorespiratory effects of romifidine in cats

Abstract

ObjectiveTo evaluate the sedative, analgesic, and cardiorespiratory effects of intramascular (IM) romifidine in cats. Study designProspective, randomized experimental trial. AnimalsTen healthy adult cats. MethodsRomifidine (100, 200, and 400 μg kg−1) or xylazine (1 mg kg−1) was given IM in a cross‐over study design. Heart rate (HR), respiratory rate (RR), rectal temperature (RT), hemoglobin saturation, oscillometric arterial pressure, and scores for sedation, muscle relaxation, position, auditory response, and analgesia were determined before and after drug administration. Time to recumbency, duration of recumbency, and time to recover from sedation were determined. Subjective evaluation and cardiorespiratory variables were recorded before and at regular intervals for 60 minutes after drug administration. ResultsBradycardia developed in all cats that were given romifidine or xylazine. No other significant differences in physiologic parameters were observed from baseline values or between treatments. Increasing the dose of romifidine did not result in increased sedation or muscle relaxation. Cats given xylazine showed higher sedation and muscle relaxation scores over time. Analgesia scores were significantly higher after administration of romifidine (400 μg kg−1) and xylazine (1 mg kg−1) than after romifidine at 100 or 200 μg kg−1. Duration of lateral recumbency was not significantly different between treatments; however, cats took longer to recover after administration of 400 μg kg−1 romifidine. Conclusions and clinical relevanceBradycardia is the most important adverse effect after IM administration of romifidine at doses ranging from 100 to 400 μg kg−1 or 1 mg kg−1 of xylazine in cats. The sedative effects of romifidine at 200 μg kg−1 are comparable to those of 1 mg kg−1 of xylazine, although muscle relaxation and analgesia were significantly less with romifidine than with xylazine.