模拟深埋条件下挤压复合伤大鼠生命耐受力及心电图变化

目的探讨模拟深埋条件下持续挤压伤复合低氧缺水缺食大鼠的生命耐受力及其心电变化规律与特点。方法 Wistar清洁级雄性大鼠42只,经钳夹法作用于双后肢（压力为4.5±0.3 kg）,置入常压低氧舱内（氧浓度为10±0.1%）,禁食水。其中18只于持续挤压后1、3、5、6.5 d4个时间点行心电图检查,并均与挤压前做自身对照。25只大鼠用作生命耐受时间观察（其中一只大鼠既做心电图检查,又做生命耐受观察）。结果 25只大鼠于持续挤压后4.2～6.8 d内全部死亡（平均活存时间5.3±0.7 d）,挤压后,13/18只大鼠（72.2%）心电图发生明显变化,包括：ST段下移、T波高尖、P波低平或消失、QRS波群增宽、QT间期延长和异常J波。其中挤压后1 d见ST段下移,3 d见ST段下移、T波高尖、P波消失或低平,5 d见ST段下移、T波高尖、QT间期延长,6.5 d见QRS波群增宽、QT间期延长及异常J波。结论模拟深埋挤压伤复合低氧缺水缺食条件下,大鼠死亡时间为4.2～6.8 d,大鼠心电图发生明显的异常,如：ST-T改变、P波低平或消失、QT间期延长和异常J波等,具有高发性、速发性、进行性和多样性特点。

Life-endurance and ECG changes of rats with combined injury of crush,hypoxia and hungry simulating the condition of deep burying

Objective To investigate the life-endurance and electrocardiogram changes of rats which were under conditions of crush injury, combined with hypoxia and food and water deprivation, simulating the situation of deep compressed burying. Methods Bilateral hind limbs of 42 adult male Wistar rats of clean grade were tailor-made clip pressure （4.5 ± O. 3）kg ]. The rats were put into a hypoxic compartment in which the oxygen concentration was maintained around the level of （10% ±0.1 ）% , and no food and water were given. Electrocardiogram （ECG） of 18 rats were recorded at d 1, d 3, d 5, d 6.5 after compression and their ECG before compression were used as self control. 25 rats were used to observe the life endurance. Results 25 rats died after continuous compression, with a mean survival time of （5.3 ± 0.7）d. The ECG in 72% of the rats （13/18） high and sharp T waves, absent or low P waves, had distinct changes including ST-segment depression, wide QRS complexes, QT interval prolongation and ab- normal J waves. Among them, the ST-segment depression appeared at d 1, the ST-segment depression, high and sharp T waves and absent or low P waves occurred at d 3, ST-segment depression, high and sharp T waves, and QT interval prolongation occurred at d 5, wide QRS complexes, QT interval prolongation and abnormal J waves occurred at d 6.5 after compression. Conclusions Rats died in 4.2 to 6.8 days under the condition of compression combined with hypoxia, food and water deprivation. ECG of rats showed distinct changes such as ST-T changes, absent or low P waves , QT interval prolongation, and ab- normal J waves with characteristics of high incidence, rapid occurrence, progressive diversity.