The role of venous pressure variability during hemodialysis in the prediction of impending arteriovenous graft occlusion

Abstract

Background:

Elevated venous pressure during hemodialysis (VP_HD) is associated with arteriovenous graft (AVG) stenosis. This study investigated the role of VP_HD variations in the prediction of impending AVG occlusion.

Methods:

Data were retrieved from 118 operations to treat AVG occlusion (occlusion group) and 149 operations to treat significant AVG stenosis (stenosis group). In addition to analyzing the VP_HD values for the three hemodialysis (HD) sessions prior to the intervention, VP_HD values were normalized to mean blood pressure (MBP), blood flow rate (BFR), BFR × MBP, and BFR² × MBP to yield ratios for analysis. The coefficient of variation (CV) was used to measure relative variations.

Results:

The within-group comparisons for both groups revealed no significant differences in the VP_HD mean and CV values among the three HD sessions prior to intervention. However, the CVs for VP_HD/MBP, VP_HD/(BFR × MBP), and VP_HD/(BFR² × MBP) exhibited significant elevation in the occlusion group during the last HD session prior to intervention compared with both the penultimate and antepenultimate within-group HD data (p < 0.05). In the receiver operating characteristic curve analysis, the CV for VP_HD/(BFR² × MBP) was the only parameter able to discriminate between the last and the penultimate HD outcomes (p < 0.001). According to a multivariate analysis, after controlling for covariates, CV for VP_HD/(BFR² × MBP) >8.76% was associated with a higher risk of AVG thrombosis (odds ratio: 3.17, p < 0.001).

Conclusions:

Increasing the variation in VP_HD/(BFR² × MBP) may increase the probability of AVG occlusion.