Departments of Anesthesiology and Reanimation, School of Medicine, Zonguldak Karaelmas University, Zonguldak, Turkey.
Reg Anesth Pain Med. 2009 Nov-Dec;34(6):565-8. doi: 10.1097/aap.0b013e3181bfbe35.
We evaluated the effects of dexmedetomidine pretreatment on bupivacaine cardiotoxicity in anesthetized rats.
Sixteen Wistar-Albino male rats (300-400 g) were anesthetized with ketamine. Electrocardiographic and invasive blood pressure monitoring were performed, and the results were continuously recorded. The rats were randomized into 2 groups. In group D, rats were pretreated with intravenous dexmedetomidine at a dose of 10 Kg/kg (n = 8), whereas in group S, rats were pretreated with intravenous saline (n = 8). Fifteen minutes later, bupivacaine was infused at a rate of 3 mg/kg per minute until cardiac asystole occurred. The timing of specific cardiotoxic events (a 25%, 50%, and 75% reductions of mean arterial pressure and heart rate as well as occurrence of the first arrhythmia and asystole) was recorded.
Dexmedetomidine pretreatment reduced the heart rates and mean arterial pressures of the rats who received it (P G 0.05). Dexmedetomidine pretreatment before bupivacaine administration also significantly increased the time to the 25%, 50%, and 75% reductions in mean arterial pressure and the time to the 25% and 50% reductions in heart rate (P G 0.05). In addition, dexmedetomidine significantly increased the time to first arrhythmia and time to asystole (P G 0.05) in the rats who received it before receiving bupivacaine.
Dexmedetomidine pretreatment delays the effects of bupivacaine cardiotoxicity.
我们评估了右美托咪定预处理对麻醉大鼠布比卡因心脏毒性的影响。
16 只 Wistar-Albino 雄性大鼠（300-400 g）用氯胺酮麻醉。进行心电图和有创血压监测，并连续记录结果。将大鼠随机分为 2 组。在 D 组中，大鼠静脉给予右美托咪定 10 Kg/kg（n = 8）预处理，而在 S 组中，大鼠静脉给予生理盐水（n = 8）预处理。15 分钟后，以 3 mg/kg/分钟的速度输注布比卡因，直到出现心脏停搏。记录特定心脏毒性事件（平均动脉压和心率降低 25%、50%和 75%以及首次心律失常和心脏停搏的发生时间）的时间。
右美托咪定预处理降低了接受它的大鼠的心率和平均动脉压（P G 0.05）。布比卡因给药前给予右美托咪定预处理还显著增加了平均动脉压降低 25%、50%和 75%以及心率降低 25%和 50%的时间（P G 0.05）。此外，右美托咪定显著增加了接受它的大鼠发生首次心律失常和心脏停搏的时间（P G 0.05）。
右美托咪定预处理延迟了布比卡因心脏毒性的作用。
