丙泊酚复合异氟醚控制性降压对脑氧代谢的影响

Effects of induced hypotension with isoflurane combined with propofol on cerebral oxygen metabolism

目的探讨丙泊酚复合异氟醚控制性降压期间对颅脑手术病人脑氧代谢的影响.方法选择28例ASA Ⅰ～Ⅱ级的择期脑瘤手术病人,随机均分为异氟醚降压(Ⅰ)组,丙泊酚复合异氟醚联合降压(Ⅱ)组.降压幅度与诱导前相比较,MAP下降30%～40%,维持30 min.分别于降压前、中、后进行血气分析和血糖测定,计算动-颈内静脉血氧含量差(Da-jvO2)和脑氧代谢率(CERO2).结果两组降压效果无显著性差异,降压期间HR均明显加快;降压30 min时Da-jvO2、CERO2Ⅱ组低于Ⅰ组(P＜0.05,P＜0.01);两组于降压前BGa、BGjv渐升高,而Da-jvBG降压前较麻醉前明显下降,组间无显著性差异.结论丙泊酚复合异氟醚控制性降压期间降低脑氧代谢的作用优于单纯使用异氟醚.

Objective To study the effects of induced hypotension with isoflurane combined with propofol on cerebral oxygen metabolism during craniotomy. Methods Twenty-eight ASA Ⅰ - Ⅱ patients undergoing selective craniotomy were enrolled in the study. The patients were randomized into two groups with 14 cases each. Propofol was only administered on the bases of isoflurane inhalation in group Ⅱ. Mean arterial pressure（MAP） was reduced by 30%-40% and maintained at this level for 30 min. Blood gas analysis and glucose measurement were carried out by taking blood samples from right internal jugular vein bulb and radial artery, and arterial to jugular bulb venous oxygen content difference （Da-jvO2） and cerebral oxygen extraction rate （CERO2） were calculated before,during and after induced hypotension. Results MAP was kept well at the desirable level and HR increased significantly during controlled hypotension in two groups. Compared with those in group Ⅰ , Da-jvO2 and CERO2 were decreased significantly in group Ⅱ . Compared with those before anesthesia, in both groups BGa and BGjv were increased, and Da-jvBG was decreased significantly before hypotension.Conclusion Isoflurane combined with propofol provided an adequate induced hypotension with a lower cerebral oxygenation than isoflurane inhalation alone.