颅内加压法巴马小型猪脑死亡模型建立过程中血压和心率的变化

Changes of blood pressure and heart rate during the establishmentof Ba-ma mini pigs brain-dead model by increasing intracranial pressure

目的 观察缓慢间断颅内加压法巴马小型猪脑死亡模型建立过程中血压和心率的变化。方法 巴马小型猪16头,随机分为2组:对照组(C组) ,5头,仅行麻醉维持;脑死亡组(B组) ,11头,应用改进的缓慢间断颅内加压法建立脑死亡模型。监测实验过程中动物平均动脉压(MAP)和心率(HR)变化。结果 B组中10头(10头/11头)建立脑死亡模型,1头(1头/6头)在开始颅内加压后“心肺死亡”。与C组比较,B组颅内加压后MAP和HR变化显著:(1)MAP和HR随着间断颅内加压呈波浪式上升和下降,总体呈升高趋势;颅内加压过程中MAP (176.91±3 3 .2 9)mmHg(1mmHg =0 .13 3kPa)和HR (182 .71±2 5 .67)次/分,与颅内加压前MAP (117.60±13 .75 )mmHg和HR(94.5 0±9.2 0 )次/分比较,差异有统计学意义(P <0 .0 5 )。(2 )确认脑死亡后,MAP和HR缓慢下降;直到MAP≤60mmHg或收缩压≤90mmHg ,需依赖液体支持来维持血压的稳定。与C组比较,确认脑死亡3h后,B组MAP差异有统计学意义(P <0 .0 5 ) ;确认脑死亡6h后,B组HR差异无统计学意义(P >0 .0 5 )。

Objective To investigate the changes of blood pressure and heart rate (HR) during the establishment of brain-dead model with Ba-ma mini pigs by increasing intracranial pressure (ICP) in a slow and intermitted way.Methods Sixteen Ba-ma mini pigs were randomized into 2 groups.In control group (group C, n =5),only anestheisa was maintained.In brain-dead group (group B, n =11),brain-dead model was established by increasing ICP in a modified,slow and intermittent way.Mean aterial pressure (MAP) and HR in 2 groups were monitored.Results In group B,10 out of 11 Ba-Ma mini pig brain-dead models were established,and 1 out of 6 died of cardiac and pulmonary death at the beginning of increasing ICP.The changes of MAP and HR in group B were more significant than in group C after increasing ICP:(1) MAP and HR fluctuated and showed the increased tendency with intermittently increasing ICP;The mean MAP and HR during increasing ICP were (176.91± 33.29) mm?Hg (1?mm?Hg=0.133?kPa) and (182.71± 25.67) beats/min respectively,which were significantly higher than before increasing ICP [(117.60± 13.75) mm?Hg and (94.50± 9.20) beats/min respectively, P < 0.05]; (2) After the confirmation of brain death,MAP and HR began to decrease slowly;MAP was decreased constantly till MAP≤60 mm?Hg or systolic blood pressure≤90 mm?Hg,and stable blood pressure was maintained by circulation support.Three h after the initial confirmation of brain death,there was significant difference in MAP between group B and group C ( P < 0.05), but there was no signficant difference between the two groups after 6 h ( P > 0.05). Conclusion BP and HR during the establishment of Ba-ma mini pigs brain-dead model by increasing ICP showed characteristic changes.