Tramadol in CRI VS tramadol bolus during abdominal surgery in dog

Tramadol in CRI VS tramadol bolus during abdominal surgery in dog Costa GL. (1), Interlandi C. (1), Spadola F., Macrì F., Leonardi F.(2). (1) Department of Veterinary Sciences, University of Messina, Italy. (2) Department of Veterinary Sciences, University of Parma, Italy. Keywords : tramadol, CRI, isoflurane, telazol, acepromazine. This study aims to compare the effects of tramadol administered as a constant rate infusion to tramadol administered as a single intravenous bolus. Forty female dogs were anesthetized with : tiletamine/zolazepam 5mgkg-1 intravenously (IV) and acepromazine 0,05 mgkg-1 IV, oxygen and isoflurane. Animals were divided in two groups: Group A received 4mgkg-1 of tramadol IV as a single bolus, while group B received 1.5 mgkg-1 of tramadol IV as a single bolus followed by a tramadol constant rate infusion (CRI) at 2,6 mgkg-1h-1. The following parameters were recorded: heart rate, respiratory rate, blood pressure (systolic, diastolic, mean), body temperature, EtCO2, SpO2 and the concentration of inspired and expired isoflurane. The heart rate increased in both groups after administration of the inyectable anesthetics (tiletamine/zolazepam and acepromazine) however, after intubation and administration of tramadol it decreased in both groups. The respiratory rate decreased after administration of the inyectable anesthetics in both groups and remained constant during the entire surgery. The pressure remained constant and withing normal limits throughout the entire study. The SPO2 remained withing physiological limits during the study. The isoflurane inspired and expired levels were statistically in lower in group B (2.3/2% VS 1.8/1.6%). CRI of tramadol decreases isoflurane requirements compared to tramadol administered as a bolus. The presence of transient twitching was observed in individuals that received tramadol as a bolus while no side effects were observed in any of the animals belonging to group B. 1: De Wolff MH, Leather HA, Wouters PF. 1999 Effects of tramadol on minimum alveolar concentration (MAC) of isoflurane in rats. Br J Anaesth. 83,780-3. 2: Itami T ,Kawase K, Tamaru N et al, 2013 Effects of asingle bolus intravenous dose of Tramadolon minimum alveolar concentration (MAC) of sevoflurane in dogs. J Vet Med Sci. 75,613-8.