Cardiopulmonary and acid-base effects of tramadol in cats anesthetized with sevoflurane

Abstract

ABSTRACT:The experiment assessed the cardiorespiratory and hemogasometric profiles in female cats under sevoflurane resulting from the administration of tramadol. Twenty clinically healthy adult female cats separated equally into two groups: control group (CG) and tramadol group (TG) were sedated with intramuscular acepromazine (0.05 mg/kg), followed by anesthetic induction intravenous propofol (5mg/kg). After endotracheal intubation, animals were maintained on sevoflurane in oxygen administered using a non-rebreathing (Baraka) circuit. The oxygen flow-rate was maintained at 2 L per minute. Fifteen minutes after induction, either 0.05 ml/kg 0.9% saline solution or 2mg/kg tramadol were administered, both intramuscularly, to the animals in CG and TG, respectively. The period of time immediately previous to these administrations was considered as moment zero (T0). The variables were again measured 15 minutes later (T15) and subsequently in 15 minute intervals for a total of sixty minutes (T30, T45 and T60). The results were statistically evaluated through variance analysis of repeated measures (ANOVA) followed by a Tukey test or Student t-test with the nullity hypothesis rejection level set to p<0.05. The use of tramadol reduced cardiac frequency (CF), systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and mean arterial pressure (MAP). There was a reduction of the respiratory frequency (RF) and an elevation of the PaCO 2 . The body temperature (ºC) lowered in both groups throughout the experiment. The results allow us to conclude that tramadol in cats anesthetized with sevoflurane does not undergo significant cardiorespiratory and blood-gas changes, although there are significant differences in some parameters between groups, all results remained within feline standard physiological values.

Effects of dexmedetomidine or tramadol continuous rate infusions on the propofol requirements and cardiorespiratory variables in propofol-ketamine-midazolam anaesthetised cats

“…In addition, the use of tramadol (2 mg/kg i.m.) in cats anaesthetised with sevoflurane results in a decrease in the fR and an increase in the arterial CO 2 blood levels, without any clinical significance (De Lacerda et al 2016). The stability of SpO 2 discards any possible hypoxemic events arising from the different treatments, a finding also observed in cats treated with the ketofol combination with or without dexmedetomidine (Ravasio et al 2012), as well as in cats treated with tramadol during anaesthesia with sevoflurane (De Lacerda et al 2016).…”