急性超大容量血液稀释在脊柱外科手术中的应用

目的对急性超大容量血液稀释（acute extreme hypervolemic hemodilution,AEHH）方法在脊柱外科手术中应用的安全性及有效性进行研究与评价。方法2003年1月～6月,对13例择期行脊柱外科手术的患者实施AEHH,其中男8例,女5例。年龄16～56岁,体重50～75kg。胸腰椎爆裂骨折前路减压植骨内固定手术11例,脊柱侧弯矫正术2例。术前红细胞压积（haematocrit,Hct）为0.363～0.481,无心、肺、肝、肾功能及凝血功能异常。动态监测术中血流动力学及红细胞比容改变,测定扩容前、扩容结束、扩容结束后60min、120min及手术结束弹力血栓图（thromboelastography,TEG）各参数、动脉血气以及电解质的变化,并对患者术中液体出入量进行统计。结果13例患者采集自体血血量1050～1575ml,平均1419±198ml;血浆代用品输入量2100～3150ml,平均2838±397ml;手术出血量1000～3130ml,平均1747±743ml;术中尿量450～1270ml,平均871±374ml;净入量1206～2661ml,平均1863±598ml。除1例因术中出血量达3130ml而输入异体血400ml外,余均未输异体血。术中平均动脉压、中心静脉压和心率均在正常范围内且保持平稳,扩容结束时Hct明显低于基础值,扩容结束后逐渐回升,手术结束时虽然仍低于基础值,但明显高于扩容结束时测定值,差异有统计学意义（P〈0.05）。TEG结果示除反应时间在扩容后60min较扩容前明显延长（P〈0.05）外,凝血时间、最大振幅和血凝块形成速率在手术中均无明显改变;血气分析各时间点各项指标比较差异均无统计学意义（P〉0.05）。结论AEHH能安全有效地应用于脊柱外科手术中,减少围术期异体血的用量。

APPLICATION OF ACUTE EXTREME HYPERVOLEMIC HEMODILUTION IN SPINE SURGERY

OBJECTIVE: To evaluate the security and validity of the acute extreme hypervolemic hemodilution (AEHH) in spine surgery. METHODS: Thirteen patients (8 males, 5 females; age, 16-65 years; weight, 50-75 kg) who had undergone major spine operations were enrolled in this study. Eleven of them had undergone anterior decompression, who were given the grafting and the internal fixation for their thoraco-lumber spinal burst fractures; the other 2 patients were given the correction operation for their scoliosis. The baselines of the haematocrit (Hct) were 0.363-0.481 before operation. The patients had no cardiac, pulmonary, hepatic or renal dysfunction or coagulation abnormality. The hemodynamic status and the haematocrit were observed during operation. The parameters of thromboelastography (TEG), arterial blood gas, and electrolytes were measured and observed at the following time points: before AEHH, after AEHH, 60 minutes after AEHH, 120 minutes after AEHH, and the end of the operation. The total fluid volume was recorded. RESULTS: The autologous blood volume was 1 050-1 575 ml (average, 1 419 +/- 198 ml), plasma substitute 2 100-3 150 ml (average, 2 838 +/- 397 ml), blood loss 1 000-3 130 ml (average, 1 747 +/- 743 ml), urine 450-1 270 ml (average, 871 +/- 374 ml), and the net blood transfusion 1 206-2 661 ml (1 863 +/- 598 ml). The homogenous blood of 400 ml was transfused in 1 patient for making up the blood loss of 3 130 ml. There were no statistically significant differences in the hemodynamic measurements, arterial blood gas, and electrolyte variables when compared with the baseline values before the hemodilution (P > 0.05). The reaction time of TEG was longer 60 minutes after AEHH than before AEHH (P < 0.05); the other parameters of TEG had no differences when compared with the baseline values (P > 0.05). CONCLUSION: The AEHH is safe and efficient in reduction of the perioperative homogenous blood transfusion in spine surgery.