麻醉期间硝普钠降压对脑循环与心功能影响的实验研究

本文报告静脉普鲁卡因复合麻醉期间,使用硝普钠降压,观察犬右侧颈内动脉和椎动脉的血流变化,动脉血和颈内静脉血氧分压、动静脉血糖差值的改变和全身血流动力学等指标。结果表明:降压期问脑血流有一定程度的下降,尤以平均动脉压(MAP)7.9kPa(60mmHg)时更为显著。但对脑代谢无明显影响,心排血量增加,外周阻力减低,颈内静脉血氧分压维持在正常水平,显示脑组织并无缺氧情况。提示用硝普钠进行控制性降压是安全的。

Effects of Controlled Hypotension with Nitroprusside on Cerebral Blood Flow and Metabolism

The effects of controlled hypctesion with sodium nitroprusside on cerebral blood flow and metabolism were studied in 8 mongrel dogs during intravenous procaine balanced anesthesia. The blood flow of right internal carotid artery and vertebralanery and aorta was measured with electromagnetic iiowmeters. Blood gas and glucose of both arterial and internal jugular venous blood samples were determined and the differences in both oxygen and glucose contents between artery and internal jugular vein blood were calculated. Our experimental results revealed that cerebral blood flow reduced as mean artery blood pressure decreased .especially below 7.9 kPa (60mmHg).Cerebral metabolism remained unchanged and cardiac output increased with decreasing of peripheral vascular resistance. Oxygen tension of jugular venous blood remained within normal range, indicating no ischemia of brain tissue. From the above we may conclude that controlled hypotension with sodium nitroprusside influences cerebral circulation and metabolism negligibly and that it can be safely used in clinical practiee.