The effects of lidocaine with epinephrine and thymoquinone on bupivacaine-induced cardiotoxicity

Bupivacaine is one of the local anesthetics which is most commonly used in regional anesthesia. It may lead to ventricular arrhythmias and cardiac arrest when it was given to systemic circulation by mistake. The aim of the present study is to research the effects of thymoquinone and lidocaine with epinephrine at different doses on bupivacaine-induced cardiotoxicity. The study was planned in two group. Bupivacaine at a dose of 3 mg/kg/min was given via intravenous (iv.) infusion until the asystole time to rats in both group. 12 male Wistar albino rats were divided into two subgroups in Group 1. I) Control and II) Thymoquinone. Thymoquinone at a dose of 20 mg/kg/ml was given via intraperitoneal 10 min prior to the bupivacaine infusion. 24 male Wistar albino rats were divided into 4 groups in Group 2. I) Control, II) Lidocaine with epinephrine, 1 mg/kg, III) Lidocaine with epinephrine, 3 mg/kg and IV) Lidocaine with epinephrine, 6 mg/kg. Lidocaine with epinephrine was given via iv. with infusion at the doses of 1, 3 and 6 mg/kg/min. In the thymoquinone group, the 50% decreament time in mean arterial blood pressure (MABP) was significantly increased compared to control group (P<0.05). Lidocaine with epinephrine at a dose of 1 mg/kg significantly increased the asystole time, initial arrhythmia time, %75 decreament time in MABP and heart rate (HR) (P<0.05). Thymoquinone revealed a limited protective effect. The studies that research the different administration routes of thymoquinone and the effects of its chronic therapy should be undertaken. In this thesis, for the first time, it was reported that lidocaine with epinephrine increased the asystole time and improved the hemodynamic parameters. In clinical application, the simultaneous application of lidocaine with epinephrine and bupivacaine may reduce the cardiotoxic risk of bupivacaine.