控制性降压下俯卧位脊柱手术全麻患者眼内压及眼底动脉血液动力学的变化

摘要

Objective To explore the safe threshold of controlled hypotension in prone position spinal surgery by real - time monitoring of intraocular pressure(IOP)and hemodynamic changes. Methods Sixty patients prepared for prone position spinal surgery were selected and con-trolled hypotension with nitroglycerin during anesthesia. Nine time points(T0 ~ T8)were selected to detect IOP and hemodynamic indexes with to-nometer and color doppler flow imaging. Results After the induction of anesthesia,IOP,resistance index(RI)and pulsatility index(PI)in-creased while peak systolic velocity(PSV)and end diastolic velocity(EDV)decreased as time went by;and all the indexes changed mostly at T5,which were all different significantly compared to T0( P ﹤ 0. 05 or P ﹤ 0. 001). After the extubation,all indexes restored as time went by;and there was no significant difference between those at T8 and T0( P ﹥ 0. 05). Further more,there were 4 cases of central retinal artery occlu-sion(CRAO)at T5,in which arterial pressure was lower than the average level(64. 8 ± 8. 66 mmHg). Conclusion Controlled hypotension in prone position spinal surgery has certain effect on the intraocular pressure and hemodynamic indexes,and we should control the hypotensive per-centage in the scope of 30% and ensure the mean arterial pressure not less than 65 mmHg to protect the patient′s optic nerve.%目的：实时监测控制性降压对俯卧位脊柱手术全麻患者眼内压及眼底动脉血液动力学的影响，以探讨其安全阈值。方法随机选取预行俯卧位脊柱全麻手术的60例外科患者为研究对象，麻醉过程中采用硝酸甘油控制性降压。选择诱导前10 min（T0）、诱导后10 min（T1）、俯卧位后10 min（T2）、控制性降压10％（T3）、20％（T4）、30％（T5）、恢复正常血压10 min（T6）、术毕平卧位后10 min（T7）、拔出气管导管后10 min（T8）9个时间点，使用笔式眼压计测量眼内压（IOP），使用彩色多普勒超声仪测定右眼视网膜中央动脉和睫状后动脉的血流动力学特征收缩期最高流速（ PSV）、舒张末期最低流速（EDV）、阻力指数（RI）及搏动指数（PI）。结果患者诱导麻醉后，IOP、RI 及 PI 随着麻醉时间的延长呈升高趋势，PSV 及 EDV 呈降低趋势，T5时，各指标差异性最大，均较 T0有显著差异（ P ﹤0.05或﹤0.001）。T6后，各指标有所恢复，T8各指标较 T0无统计学差异（ P ﹥0.05）。另外，T5时4例患者出现视网膜中央动脉闭塞（CRAO）征象，其 MAP 均低于患者该时段平均水平（64.8±8.66 mmHg）。结论控制性降压对俯卧位脊柱手术全麻患者的眼内压及眼底动脉血液动力学指征有所影响，血压降低水平控制在基线水平的30％以内，且保证目标 MAP ﹥65 mmHg，可有效保护患者视神经。