ABSTRACT

In this study, following the administration of bupivacaine, levobupivacaine and ropivacaine, we aimed to compare the cardiotoxic dosages and cardiotoxic effects of each agent.

Eighteen adult dogs each weighing 20-25 kg were randomly divided into three equally distributed groups. Bupivacaine (Group B), levobupivacaine (Group L), ropivacaine (Group R) were chosen as local anesthetics. Anesthesia was achieved by administering of 100 mg ketamine and 5 mg midazolam before the study and intravenous catheter was placed. Electrocardiographic (ECG) monitorizations were performed. Local anesthetics were infused in each group. When ECG changed, drug administration was stopped and total effective toxic dosages for each group were identified.

ECG changes between 3. and 4. minutes post-injection were determined in the bupivacaine group and cardiotoxic dosage of bupivacaine was calculated as 121.83±2.22 mg. ECG changes between 3. and 4. minutes postinjection were determined in the levobupivacaine group and cardiotoxic dosage for levobupivacaine was calculated as 135.83±8.01 mg. ECG changes between 5. and 6. minutes post-injection were determined in the ropivacaine group and cardiotoxic dosage of ropivacaine was calculated as 205.00±5.47mg. The effective toxic dosage of Group R was found statistically significantly higher than Group B and Group L (p<0.01). In Group L cardiotoxic dose was found significantly higher than Group B (p<0.01).

In conclusion, when the cardiac effects of the evaluated drugs were considered; levobupivacaine and ropivacaine were more reliable than bupivacaine, and ropivacaine was more reliable than levobupivacaine.

Keywords: Cardiotoxic Agents, bupivacaine, levobupivacaine, ropivacaine