急性低氧对家兔微血管及心电图的影响

目的　观察不同程度急性低氧对家兔微血管和心电图的影响。方法　实验采用两组家兔分别人工吸入 12 .5 %(Ⅰ组 )和 8.5 %氦氧混合气体 (Ⅱ组 ) ,模拟 40 0 0m和 65 0 0m高原急性低氧。急性低氧时间分别为 5min、10min、15min、2 0min ,于急性低氧前后观察微血管和QTc与JTc间期变化。结果　两组血流速度减慢 ,微血管口径变大。Ⅰ组QTc和JTc间期有延长 ;Ⅱ组QTc间期有延长 ,而JTc间期有缩短或不变。结论　急性低氧可使微血管血流速度减慢 ,口径变大 ,心肌去、复极化发生改变

Effects of Acute Hypoxia on Blood Capillary and Cardiogram of Rabbits

Objective To observe effects of various acute hypoxias on the blood and capillary and cardiogram.Methods Rabbits are divided into two groups (Group Ⅰ: manual inhalation of 12.5% of helium-oxygen gas mixture; Group Ⅱ: manual inhalation of 8.5% of helium-oxygen gas mixture) to simulate 4000m and 6500m highland acute hypoxias. Durations varied in 5min, 10min, 15min and 20min. Observations on blood capillaries and QTc and JTc interval changes were made before and after the acute hypoxias. Results Blood flow rates slowed down and blood capillary calibers filled out, QTc and JTc intervals extended in Group Ⅰ, in Group Ⅱ, QTc intervals extended while JTc intervals shortened or stayed unchanged. Conclusion Acute hypoxias may cause blood flow rates in blood capillaries to slow down, calibers filled out, changes in cardiac muscle depolarization and repolarization.