急性高容量血液稀释对脑氧代谢的影响

Effects of acute hypervolemic hemodilution on cerebraloxygen metabolism

目的观察急性高容量血液稀释(AHH)对脑氧代谢的影响,探讨AHH是否改变脑氧代谢的平衡。方法选择44例行肝叶部分切除的患者,随机分为实验组(H组,n=22)和对照组(C组,n=22例)。测定血气值和乳酸(LA)值,计算脑氧摄取率(CEO2)、桡动脉-颈内静脉血氧含量差(Da-jvO2)和颈内静脉-桡动脉血乳酸差(VADL)。结果H组在稀释后SjvO2升高,CEO2和Da-jvO2降低(P<0.01),其中有3例患者在稀释后SjvO2>90%;其余患者SjvO2均在正常范围内,而C组中所有患者SjvO2均未超过80%。稀释后与C组比较,H组SjvO2升高,CEO2、Da-jvO2降低(P<0.05)。结论AHH可以改善脑氧代谢,不会发生脑氧供不足,但有小部分患者可能会发生不同程度的脑血流灌注过剩问题。

Objective To observe the effects of acute hypervolemic hemodilution（AHH）on cerebral oxygen metablism and investigate whether AHH changed the balance of cerebral oxygen metablism.Methods 44 ASA I-II patients underwent lebectomy of liver were randomly allocated to two groups（group H and group C）with 22 patients in each group.The changes of arterial and jugular venous hemoglobin saturation（SjvO2）and lactate values were measured.Differences of oxygen content and lactate between arterial and jugular bulb blood（Da-jvO2）,cerebral extraction of oxygen（CEO2）were caculated.Results In group H,CVP increased significantly,but still within normal range.After AHH,SjvO2 increased significantly（P〈0.05）,whereas CEO2 and Da-jvO2 decreased significantly（P〈0.05）.SjvO2 values of 3 patients were beyond 90%.In group C,all the patients SjvO2 no more than 80%.Conclusion This study suggested that cerebral oxygen balance during AHH were well maintained in most patients,but cerebral hyperperfusion might occur in a few of patients.