高渗盐水与甘露醇对颅脑手术患者脑氧代谢的影响

Effect of hypertonic saline and mannitol on cerebral oxygen metabolism in patients undergoing neurosurgery for supratentorial glioma

目的 比较3％高渗盐水（HTS）与20％甘露醇对颅脑手术患者脑氧代谢的影响。方法 择期大脑半球胶质瘤切除术患者40例，ASAⅠ级或Ⅱ级，随机分为2组（n=20）：3％HTS组（HTS组）和20％甘露醇组（M组）。采用静吸复合麻醉，呼气末异氟醚浓度为1 MAC、血液动力学稳定15．min后，分别于15 min内静脉输注3％HTS 5．35 ml／kg或20％，甘露醇1 g／kg。L3，4珠网膜下腔置管测脑脊液压力（CSFP），行右颈静脉球穿刺置管、采血，测定颈静脉球氧饱和度。分别于输注前（T0）、输注完即刻（T1）、输注完15min（T2）、30min（T3）、60min（T4）、120min（T5）监测CSFP;于T0、T3-T5时监测平均动脉压，采集颈静脉球部和桡动脉血，进行血气分析，计算动脉-静脉氧含量差（Da-jvO2）、脑氧摄取率（CERO2）。结果 与T0比较，2组CSFP在T2-T5时降低，Da-jvO2和CERO2在T4，5时降低（P〈0．05）;与M组比较，HTS组CSFP在T2时降低（P〈0．05）。结论 3％HTS与20%甘露醇均可有效地降低颅内压，改善颅脑手术患者的脑氧代谢。

Objective To study the effect of hypertonic saline （3%） and 20% mannitol on cerebral oxygen supply and consumption in patients during elective neurosurgery for supratentorial glioma. Methods Forty ASA Ⅰ or Ⅱ patients aged 16-60 yr undergoing excision of supratentorial glioma were randomly divided into 2 groups （n = 20 each） ： Ⅰ hypertonic saline group （HS） and Ⅱ 20% mannitol group （M）. The patients were premedicated with intramuscular phenobarbital 0.1 g and scopolamine 0.3 mg. Radial artery was connulated for BP monitoring and blood sampling. Internal jugular vein was cannulated and advanced cephalad until jugular bulb for blood sampling. An epidural catheter （17 G） was inserted into the subarachnoid space at L3-4 interspace for measurement of eereabral-spinal fluid （CSF） pressure. Anesthesia was induced with midazolam 1.5-2.0 mg, fentanyl 3 μg/kg , 2.5% thiopental 4-6 mg/kg and veeuronium 0.1 mg/kg and maintained with isoflurane inhalation （1 MAC）, fentanyland vecuronium （0.05 mg·kg^-1· h^-1）. The patients were mechanically ventilated and PET CO2 was maintained at 30-35 mm Hg. 20% mannitol 1 g/kg or 3% hypertonic saline 5.35 ml/kg was given intravenously over 15 min when end-tidal isoflurane concentration reached 1 MAC and hemodynamics was stable. ECG, HR, MAP, CSF pressure and SpO2 were continuously monitored. Arterial and jugular bulb venous blood samples were taken for determination of PaO2 , SaO2 , PjvO2 and SjvO2 before hypertonic saline or maunitol infusion （ T0 ） and immediately （T1） at 15, 30, 60, 120 min after infusion was completed （T2-5 ）. Cerebral arterial-jugular bulb venous oxygen content differences （Da-jvO2 ） and cerebral oxygen extraction rate （CERO2） were calculated. Results CSF pressure significantly dropped from T2 until T5 in both groups. Da-jvO2 and CERO2 were significantly reduced at T4-5 in both groups. There was no significant difference between the 2 groups. Conclusion Hypertonic saline （3 % ） is as efficient as mannitol （20%） in reducing intracranial pressure and improving cerebral oxygen metabolism in patients during neurosurgery for supratentorial glioma.