高容血液稀释联合控制性降压对腰椎手术病人术中胃黏膜pH值的影响

Effects of acute hypervolemic hemodilution combined with controlled hypotension on gastric intramucosal pH in patients undergoing spinal surgery

目的:探讨术前急性高容血液稀释联合术中控制性降压对胃黏膜pH值的影响。方法:择期行腰椎骨折椎板减压、切复内固定病人30例,随机分为高容血液稀释联合控制性降压组(联合组)和单纯控制性降压组(对照组)。观察比较联合组插管后稀释前(T0)、稀释后降压前(T1)、降压后30min(T2)和停降压后30min(T3)四个时间点,对照组插管后降压前(T1)、降压后30min(T2)和停降压后30min(T3)三个时间点的pHi,PgCO2,PgCO2-PaCO2和动脉血气的变化情况。结果:pH值联合组T1,T2,T3明显低于T0(P<0.01);PaCO2对照组T3较T1明显升高(P<0.05),且高于对照组(P<0.05);PETCO2对照组T3明显高于T1(P<0.05);PgCO2对照组T2较T1升高(P<0.05),且高于对照组(P<0.05);PgCO2-PaCO2对照组T2较T1升高(P<0.01),pHi对照组T2较T1升高(P<0.01)。结论:硝普钠控制性降压可降低可引起一过性胃肠道微循环障碍,术前急性高容血液稀释可以改善术中控制性降压对胃肠道微循环的影响。

Objective： To investigate the influence of acute hypervolemic hemodilution（AHH） combined with controlled hypotension（CH）on gastric intramucosal pH in patients undergoing spinal surgery. Methods： 30 ASk Ⅰ-Ⅱ patients aged 18-61 years,weighing 45-70kg scheduled for decompression of spinal cord by laminectomy and internal fixation for fracture of lumbar spine were randomly divided into two groups：group Ⅰ AHH＋CH（n=15） and group Ⅱ CH alone （n=15）. Blood samples were taken for blood gas analysis and determining pHi, PgCO2, PgCO2-PaCO2, PETCO2 before AHH（T0） after was performed（T1）,30min after CHwas induced （T2） and 30 min after termination of CH （T3） in group Ⅰ and in group Ⅱ before CH （T1）,30 min after induction of CH （T2） and 30 min after termination of CH （T3）. Results： In group Ⅰ compared with the baseline values （T0） pH significantly decreased after AHH（T1,T2,T3） （P〈0.01）.In group Ⅱ PETCO2 and PaCO2 were higher at T3 than at T1 （P〈 0.05）; PgCO2-PaCO2 and pHi were lower at T2 than at T1 （P〈 0.05 or 0.01）. At T3 PaCO2 in group Ⅰ was lower than that in group Ⅱ（P〈O.05）; At T2 in group Ⅰ PgCO2 was lower than that in group Ⅱ （P〈 0.05）. Conclusion： There is transient disturbance of gastro-intestinal microcirculation during deliberate hypotension as shown by decreased pHi while AHH combined with CH can improve gastrointestinal microcirculation perfusion.