食管超声多普勒监测急性高容量血液稀释对血液动力学的影响

目的　应用经食管超声多普勒血液动力学监测仪 ,观察全麻下急性高容量血液稀释(HHD)的血液动力学和氧供 (DO2 )变化。方法　选择 1 5例ASAI～II级择期行非心脏手术患者。麻醉诱导插管后持续监测心输出量 (CO)、每搏量 (SV)、心脏指数 (CI)、血流峰速度 (PV)、血流加速度(Acc)和左室射血时间指数 (LVETi) ,每隔 5分钟输入MAP值后计算出系统血管阻力 (SVR)值。麻醉平稳和各项监测完成后 1 0min ,在 30min内输注 6 %羟乙基淀粉 (HES) 2 0ml/kg。记录 6 %HES输注前、输注 1 5和 30min时的各项监测数据 ,并抽取动脉血液样本行血气分析并计算DO2 。结果　与HHD前相比 ,血气各参数 (pH、PaO2 、PaCO2 、BE)均无明显差异 (P >0 0 5 ) ,而 6 %HES输注 1 5和30min血红蛋白 (Hb)含量、红细胞比积 (Hct)均明显下降 (P <0 0 5和P <0 0 1 )。 6 %HES输注 1 5和 30min时的CaO2 比HHD前明显下降 (P <0 0 5 ) ,而DO2 显著增加 (P <0 0 5 )。与HHD前测量值相比 ,6 %HES输注 1 5min ,CO、SV、CI、PV和Acc明显升高 ,SVR显著降低 (P <0 0 5 ) ;6 %HES输注 30min ,SV、PV和Acc进一步升高 (P <0 0 1 ) ,而CO、CI和SVR与 6 %HES输注 1 5min时无明显变化。MAP、HR和LVETi在HHD期间无明显变化。结论　术前输注 6 %HES 2 0ml

Transoesophageal echo-Doppler hemodynamic monitoring during acute hypervolemic hemodilution

Objective To explore the changes of hemodynamics and oxygen delivery(DO 2) by transesophageal echo Doppler during acute hypervolemic hemodilution(HHD) with 6% hydroxyethel starch(HES).Methods Fifteen patients,ASA I II,undergoing selective non cardiac surgery,were included in this study.After induction of anesthesia and tracheal intubation, cardiac output (CO),stroke volume(SV),cardiac index(CI),peak acceleration(Acc),peak velocity(PV) and left ventricular ejection time index(LVETi) were monitored respectively.MAP values were entered into the monitor every 5 min to calculate total systemic vascular resistance(SVR) values.Patients were intravenously infused with 20 ml/kg of HES(6% HAES Steril 200/0 5) within 30 min.The physiological variables were recorded and blood samples were drawn for blood gases before and 15,30 min after infusion of HES.DO 2 was calculated.Results At 15 min and 30 min after infusion of HES,hemoglobin and hematocrit significantly decreased( P< 0 05 and P< 0 01).pH,PaO 2,PaCO 2 and BE were similar to those before infusion.During HHD,DO 2,CO,SV,CI,PV and Acc increased significantly, while SVR decreased markedly( P< 0 05),and LVETi,HR and MAP remained stable compared with those before infusion.Conclusion Preoperative acute hypervolemic hemodilution(HHD) with 6% HES significantly increases the blood volume with an increase in DO 2,CO,SV and CI and a decrease in SVR, and MAP and HR remain stable indicating that HES 20 ml/kg infusion is safe in patients without cardiac diseases.