血液透析患者的内瘘血流量在预测内瘘预后中的作用

目的对维持性血液透析的患者进行内瘘血流量（Qa）的测定,随访患者的内瘘功能,了解Qa与血液透析患者的内瘘功能之间的关系。方法在患者血液透析开始后0.5h及结束前1h采用Transonic HD02 Monitor（Transonic公司生产）测定内瘘功能。对测定结果内瘘血流量过低（Qa〈600ml/min）及过高（Qa〉1800ml/min）的患者行彩色多普勒超声检查,测量内瘘血管头静脉内径、桡动脉内径,肱动脉内径,平均血流速度并排除血管腔有无狭窄。随访患者内瘘功能,并寻找Qa与血液透析患者的内瘘功能之间的关系。结果125例患者进行了内瘘功能测定。中位数Qa 870（565～1255）ml/min,Qa〈600 ml/min的有32例（25.6%）,600～1 800ml/min的有83例（66.4%）,Qa〉1 800ml/min的有10例（8.0%）。多普勒超声检查低流量组10例,其中吻合口狭窄4例（40%）,频繁穿刺点内膜增厚2例（20%）,静脉分流2例（20%）,内瘘通畅而无异常表现2例（20%）,总体内瘘功能有问题的占60%～80%;高流量组7例,均有桡动脉扩张。两组比较在头静脉内径,桡动脉内径、流速,肱动脉流速方面均有显著性差异。随访3 6月发现,低流量组患者有13例（40.6%）发生内瘘闭塞重新手术,正常流量组有7例（8.4%）,而高流量组无1例发生内瘘闭塞（0）,P〈0.001。相关性分析发现Qa与内瘘转归成负相关（r=-0.395,P〈0.001）,多元回归分析发现Qa对内瘘转归是有影响的（β=-0.316,P=0.005）。结论超声稀释法测定的血液透析患者的Qa对患者的内瘘功能的预后是有预测作用的,Qa越低内瘘闭塞的可能性越大,是血管通路（包括自身血管和人造血管）功能监测的一种良好的手段。

Blood flow in internal fistula to predict the prognosis of the fistular in hemodialysis patients

Objective To investigate the relationship between blood flow in internal fistula（Qa） and vascular access function by measuring Qa in internal fistula and following-up vascular access function in maintenance hemodi-alysis patients.Methods were measured 30 minutes after the initiation and one hour before the end of a hemodialysis session using the Transonic HD02 Monitor（Transonic Systems Inc）.For the patients with lower or higher blood flow（Qa 〈 600 ml/min or 〉1,800 ml/min）,the possibility of vascular stenosis was evaluated by color Doppler ultrasonog-raphy to measure the diameters of internal fistula vessels including cephalic vein,radial artery and brachial artery,and the mean velocity of blood flow in the fistula.Vascular access function was carefully monitored in correlation to Qa.Results Vascular access function was successfully monitored in 125 patients,in which 3 cases（2.4%） were found to have recirculation rate 〉0%,Qa 〈600 ml/min in 32 patients（25.6%）,Qa = 600-1 800ml/min in 83 patients（66.4%）,andQa 〉 1 800ml/min in 10 patients（8%）.The median Qa was 870（565-1255）ml/min.In the 10 cases with lower Qaevaluated by color Doppler ultrasonography,60%～80% had abnormal vascular access function： stenosis at the anasto-mosis site was detected in 4 cases（40%）,intima hyperplasia at the puncture site for many times in 2 cases（20%）,venous shunt in 2 cases（20%）,and patent fistula without detectable abnormalities in 2 cases（20%）.In the 7 patients with higher Qa,all accompanied with radial artery dilatation.The inner diameters of cephalic vein and radial artery,and the velocity of blood flow in radial and brachial arteries were significantly different between patients with lower Qa and those with higher Qa.During the follow-up period of 36 months,vascular access occlusion resulting in another operation was found in 13 cases（40.6%） in the patients with lower Qa,and in 7 cases（8.4%） in the patients with normal Qa,but no case in patients with higher Qa.Correlation analysis indicated that Qa and the prognosis of vascular access were negatively correlated（r =-0.395,P 〈 0.001）.Multiple regression analysis demonstrated that the Qa value influenced the prognosis of vascular access（a=-0.316,P=0.005）.Conclusions Qa measurement by ultrasound dilution technol-ogy is useful for the prediction of vascular access prognosis in hemodialysis patients.The possibility of vascular access occlusion increases in patients with lower Qa.Therefore,Qa measurement is a valuable method for the evalua-tion of vascular access function either for autologous or for graft vascular access.