UNASSIGNED: Consenting adults underwent blinded fortnightly ultrasound scanning of their AVF after creation, with scan characteristics that predicted AVF nonmaturation identified by logistic regression modeling.
UNASSIGNED: Of 333 AVFs created, 65.8% matured by 10 weeks. Serial scanning revealed that maturation occurred rapidly, whereas consistently lower fistula flow rates and venous diameters were observed in those that did not mature. Wrist and elbow AVF nonmaturation could be optimally modeled from week 4 ultrasound parameters alone, but with only moderate positive predictive values (PPVs) (wrist, 60.6% [95% confidence interval, CI: 43.9-77.3]; elbow, 66.7% [48.9-84.4]). Moreover, 40 (70.2%) of the 57 AVFs that thrombosed by week 10 had already failed by the week 4 scan, thus limiting the potential of salvage procedures initiated by that scan\'s findings to alter overall maturation rates. Modeling of the early ultrasound characteristics could also predict primary patency failure at 6 months; however, that model performed poorly at predicting assisted primary failure (those AVFs that failed despite a salvage attempt), partly because patency of at-risk AVFs was maintained by successful salvage performed without recourse to the early scan data.
UNASSIGNED: Early ultrasound surveillance may predict fistula maturation, but is likely, at best, to result in only very modest improvements in fistula patency. Power calculations suggest that an impractically large number of participants (>1700) would be required for formal RCT evaluation.
■同意的成年人在创建后每两周对其AVF进行一次盲法超声扫描,具有通过逻辑回归建模预测AVF不成熟的扫描特征。
■在创建的333个AVF中,65.8%成熟10周。串行扫描显示成熟迅速发生,而在未成熟的患者中观察到持续较低的瘘管流速和静脉直径。仅从第4周的超声参数可以对腕部和肘部AVF不成熟进行最佳建模,但只有中等的阳性预测值(PPV)(手腕,60.6%[95%置信区间,CI:43.9-77.3];弯头,66.7%[48.9-84.4])。此外,在第10周出现血栓的57个AVF中,有40个(70.2%)在第4周扫描时已经失败,从而限制了由扫描结果启动的救助程序改变整体成熟率的潜力。早期超声特征的建模也可以预测6个月时的原发性通畅性衰竭;然而,该模型在预测辅助主要故障(那些尽管有抢救尝试但失败的AVF)方面表现不佳,部分原因是在不使用早期扫描数据的情况下,通过成功抢救维持了高危AVF的通畅性.
■早期超声监测可以预测瘘管成熟,但很可能,充其量,仅导致瘘管通畅性的非常适度的改善。功率计算表明,正式的RCT评估将需要不切实际的大量参与者(>1700)。