腹主动脉灌注利多卡因对兔脊髓缺血/再灌注损伤的保护作用

目的 建立兔脊髓缺血/再灌注损伤模型,研究经腹主动脉灌注利多卡因对脊髓缺血/再灌注损伤的作用.方法 新西兰大耳白兔16只,随机分为两组:A组为对照组(8只),B组为利多卡因组(8只).静脉麻醉后气管插管,持续监测平均动脉压、心率、脉搏血氧饱和度及直肠温度.手术暴露腹主动脉和双侧髂总动脉,经股动脉置一细导管至腹主动脉内距左肾动脉1.0 cm处,并于左肾动脉开口远端0.5 cm处阻断腹主动脉,同时阻断左、右侧髂总动脉,阻断即刻开始经导管向阻断的腹主动脉远端以12 mL·kg~(-1)·h~(-1)的速度灌注实验药物.A组灌注常温0.9%氯化钠溶液(12 mL·kg~(-1)·h~(-1)),B组灌注以常温0.9%氯化钠溶液稀释的等容量利多卡因溶液(40 mg/kg),30 min后开放血管.于动物完全清醒即刻及再灌注后6、24、48 h对双后肢神经功能进行评估;再灌注48 h,取脊髓L_3～L_5 3个节段制作石蜡切片,光学显微镜下观察并计数正常的前角运动神经元.结果 清醒即刻及再灌注后6、24、48 h,B组的神经行为学评分均显著高于A组(P值均<0.05);再灌注48 h,A、B两组脊髓前角正常神经元中位数(四分位间距)分别为1(2)、9(6)个,B组显著多于A组(P<0.05).结论 腹主动脉阻断期间动脉内灌注利多卡因可减轻脊髓缺血/再灌注损伤.

Protective effects of abdominal aorta lidocaine infusion against spinal cord ischemia/reperfusion injury in rabbits

Objective To investigate the protective effect of abdominal aorta lidocaine infusion against spinal cord ischemia/reperfusion injury in rabbits.Methods Sixteen New Zealand white rabbits were evenly randomized into 2 groups:ischemic control group(group A)and lidocaine group(group B).The rabbits were endotracheally intubated and ventilated after intravenous anesthesia.The arterial pressure,electrocardiogram,percutaneous oxygen saturation,and rectal temperature were continuously monitored.The spinal cord ischemia was induced by infrarenal aortic occlusion for 30 min.The bilateral common lilac arteries were occluded simultaneously.During the occlusion,the rabbits were infused with normal saline (group A) and lidocaine (40 mg/kg, group B) at room temperature at a dose of 12 mL·kg~(-1)·h~(-1). The arteries were reopened 30 min later.The neurological statuses of animals were assessed according to the Tarlov scale system at anesthesia recovery and 6,24,48 h after reperfusion.The lumbar segments of the spinal cord(L_3-L_5)were taken out under general anesthesia for pathological examination 48 h after reperfusion,and the pathomorphologically normal motor neurons were counted.Results Group B had significantly better neurological functions than those in group A at anesthesia recovery and 6,24,48 h after reperfusion(all P<0.05).The histopathological results were consistent with the neurological scores,with the median numbers(P_(25)-P_(75))of normal motor neurons being 1(0-2)and 9(5-11)in groups A and B, respectively(P<0.05). Conclusion The results indicate that lidocaine infusion through the abdominal aorta during occlusion of abdominal aorta can relieve the ischemia/reperfusion injury of the spinal cord.