应用经颅多普勒超声指导颈动脉内膜切除术中脑血流的调节

目的探讨颈动脉内膜切除术中，经颅多普勒超声（TCD）对血压与脑血流调节指导作用。方法回顾性分析颈动脉重度狭窄患者52例，在全身麻醉下行颈动脉内膜切除术，术中应用TCD监测大脑中动脉（MCA）血流参数，根据脑血流参数的变化调控血压，并决定术中是否应用临时转流管。应用临时转流管（转流组）16例，未用36例（非转流组）。结果①52例患者术后，完全恢复且无脑缺血发作50例，因过度灌注脑出血死亡2例。②颈动脉阻断前，转流组、非转流组平均动脉压（MAP）为（111±9）、（97±15）mmHg，两组比较差异有统计学意义，P〈0．01；MCA平均血流速度（MCA Vm）为（40±12）、（39±13）cm／s，差异无统计学意义。③阻断后，转流组、非转流组MAP为（118±8）、（106±9）mmHg，较阻断前差异均有统计学意义（P〈0．01）；MCA Vm为（14±8）、（33±16）cm／s，较阻断前均下降，平均血流速度变化率为（66±6）％、（15±5）％，P〈0．01。④转流组转流中，MAP（110±13）mmHg，接近阻断前水平；MCA Vm为（44±15）cm／s，MCA Vm较阻断前提高（10±2）％。⑤开放后两组MAP为（90±12）、（93±11）mmHg；MCA Vm为（55±19）、（54±23），较阻断前提高，平均血流速度变化率为（36±3）％、（37±4）％。差异均有统计学意义，P〈0．05。⑤术中转流组、非转流组呼气末二氧化碳分压为（31．0±2．5）、（31．8±2．2）mmHg，差异无统计学意义。结论颈动脉内膜切除术中应用TCD监测，可评价脑血流灌注情况，指导血压的调控及术中转流管的选择。

Application of transcranial Doppler to guide regulation of cerebral blood flow during carotid endarterectomy

Objective To analyze the value of transcranial Doppler ultrasonography （TCD） retrospectively for perioperative management of carotid endarterectomy. Method Carotid endarterectomy was performed in 52 patients with severe carotid stenosis under general anesthesia. The blood flow parameters of middle cerebral artery （MCA） were detected by TCD during the operation. The blood pressure was regulated, and whether need a temporary vascular shunt or not was determined according to the changes of cerebral blood flow parameters. Sixteen patients （shunt group） used temporary vascular shunts and 36 patients （ nonshunt group） did not. Results ①Fifty-two patients recovered completely after the operation, 50 of them had no brain ischemic attack, and 2 patients died of cerebral hemorrhage due to hyperperfusion. ②The mean arterial pressures （MAPs） in the shunt group or non shunt group before carotid artery occlusion were 111±9 and 97±15 mm Hg respectively, and there were statistically significant differences between the two groups. The mean flow velocities of MCA（ MCA Vm） were 40±12 and 39±13 cm/s respectively, and there were no statistically significant differences between the two groups. ③The MAPs were 118±8 and 106±9mm Hg in the two groups after occlusion, and there were statistically significant differences as compared with those before the occlusion. The MCA Vm were 14±8 and 33±16 cm/s, and they decreased 66±6% and 15±5% respectively as compared with those before the occlusion. ④The MAP was 110±13 mm Hg during the bypass in the shunt group, and it was near the level before occlusion, the MCA Vm was 44±15 cm/s, it increased 10±2% as compared with that before the occlusion. ⑤the MAPs were 90±12 and 93±11 mm Hg in the two groups after opening of the carotid artery; The MCA Vm were 55±19 and 54±23, they increased 36±3% and 37±4% as compared with those before carotid artery occlusion, and there were statistically significant differences. Conclusion The application of TCD monitor