缓慢间断颅内加压法家兔脑死亡模型的建立及其病理生理变化

Establishment of brain death model for rabbits and their pathophysiological changes

目的探讨缓慢间断颅内加压法家兔脑死亡模型建立的方法及其病理生理变化。方法80只新西兰家兔随机分为假手术组（n=20）和脑死亡组（n=60）。假手术组麻醉后仅行开颅术并颅内放置Foley气囊导管，不建立脑死亡模型。脑死亡组应用改进的缓慢间断颅内加压法建立脑死亡模型，通过呼吸、循环支持维持家兔脑死亡状态。监测2组动物各时间点平均动脉压（meanarterypressure，MAP）、心率（heartrate，HR）变化。结果脑死亡组56只家兔成功建立脑死亡模型，2只家兔因麻醉意外死亡，另2只因加压不当死亡，手术成功率93．3％（56／60）；通过呼吸、循环支持可维持家兔脑死亡状态10h。与假手术组比较，脑死亡组颅内加压后MAP和HR变化显著：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。颅内加压过程中峰值MAP（400．24±18．36）mmHg（1mmHg=0．133kPa）和HR（258．00±25．70）次／min，与颅内加压前、后对应时间点MAP和HR比较，差异有统计学意义（P〈0．05）。结论用改进的缓慢间断颅内加压法可成功制作家兔脑死亡模型。其MAP和HR呈特征性变化。经有效的呼吸和循环支持，能稳定地维持家兔脑死亡状态10h。该模型有助于进一步研究脑死亡状态下家兔器官变化。

Objective To explore the way to establish the brain death model for rabbits and pathophysiological changes before and after brain death. Methods 80 healthy male New Zealand rabbits were divided into brain death group（n=60） and sham operation group（n=20）, The 60 brain death rabbits were established by increasing intracranial pressure in a modified, slow, and intermittent way. The sham operation rabbits were only maintained with anesthesia. Results The 56 brain death rabbits were established successfully and maintained for 10 h with the respiration and circulation supports. 2 rabbits died due to anesthetic accident, the other 2 died because of improper pressure. The surgical success rate is 93.3% （56/60）. The changes of mean artery pressure （MAP） and heart rate （HR） in brain death group were more significant than in sham operation group： MAP and HR fluctuated and showed the increased tendency. The mean MAP and HR during increasing intracranial pressure were （400.24±18.36） mm Hg （1 mm Hg=0. 133 kPa） and （258.00±25.70） beats/min respectively, which was significantly higher than before and after increasing intracranial pressure （P〈 0.05）. Conclusions The brain death model for rabbits could be established by increasing intracranial pressure in a modified, slow, and intermittent way successfully and maintained 10 h. the MAP and HR before and after brain death showed characteristic changes. The model is helpful to the further observation of organ changes in brain dead state.