冲击伤对大鼠心脏功能的影响

Effect of blast injury on cardiac functions of rats

作者用Ｗｉｓｔａｒ大鼠７０只，随机均分为７组，除正常对照组外，其余６组用ＢＳＴ－１型生物激波管致闭合式单纯超压伤。观察幸存大鼠伤后８ｈ到１５ｄ过程中６个时相点离体灌流工作心脏功能的变化。与对照值相比：伤后８ｈ心率减慢至５４％，心缩及心舒期分别延长到１．５和２．０倍；左室内压、＋ｄｐ／ｄｔｍａｘ和－ｄｐ／ｄｔｍａｘ分别降至５４％、３２％、４２％；伤后１周，心率维持在６０％左右，心缩期进行性地延长，可长达１．９倍，心舒期维持在１．６～１．７倍；左室内压及其变化率维持在４６％～６１％；伤后１５ｄ心功能主要指标可恢复到或接近于正常对照水平，自律性恢复早于收缩性的恢复。因此，心脏保护措施宜及早进行。

The effect of blast injury on the functions of isolated heart was studied in 70 Wistar rats weighing 200￣250 g The animals were randomly and equally divided into 7 groups:one group was the normal controls , the rats in other 6 groups suffered simple overpressure injury caused by the BST 1 model biological shock tube The experiments were performed at 8 h, 1, 3, 5, 7 and 15 days respectively after the blast injury The results were shown as follows 1. The heart rate was slowed down to 54% of the control value at 8 h after injury The systole and diastole were prolonged to 1 5 and 2 0 times of the normal control, respectively. The left intraventricular pressure(LVP), +dp/dt max , -dp/dt max were also decreased to 54%, 32% and 42%, respectively; 2. 1 week after the blast injury,the heart rate remained in about 60% of the control value.The systole was prolonged progressively and up to 190% of the control level The diastole maintained 1 6￣1 7 times of the normal value . The LVP and ±dp/dt max recovered gradually to 46%￣61% of the normal level 3 Half a month after injury, the cardiac functions may be recovered to or near the normal control level. The restoration of myocardial rhythmicity was earlier than that of the contractility Thus, the protective treatment of the cardiac function should be performed as early as possible for more than two weeks。