The role of physical examinations in detecting arteriovenous fistula stenosis among chronic hemodialysis patients: a cross-sectional study

Abstract

This study aimed to compare the accuracy of physical examinations (PE), hemodynamic parameters and flow access of arteriovenous fistula (AVF) on duplex Doppler ultrasound (DUS) in detecting AVF stenosis among hemodialysis patients after confirmed by DUS. A cross-sectional study was conducted on chronic hemodialysis patients at Cho Ray Hospital, Ho Chi Minh City, Viet Nam. Demographic and clinical data were collected through a questionnaire and medical records. All eligible patients were consecutively selected and underwent DUS, PE, and assessment of hemodynamic parameters. AVF stenosis was defined as ≥50% reduction in luminal diameter by DUS. Area under the curve and its 95% confidence interval were calculat-ed to measure the validity of tests. The median age of 324 eligible patients was 49 years (interquartile range [IQR] 38–61), with women comprising 54% of the sample. The median number of years on dialysis was 8 (IQR 5–13). Additionally, 49.7% of patients had a history of previous central venous catheter placements, while and 80.25% had a history of previous AVF creation. The percentage of patients with stenosis of ≥50% was 25.6%. Positive findings in pulse augmentation, arm elevation, swollen fistula arm, and collateral veins in ipsilateral arm were observed in 50.9%, 38.0%, 9.9%, and 8.0% of the sample, respectively. Pulse aug-mentation (AUC=0.96, 95%CI: 0.92–1.00) and arm elevation (AUC=0.74, 95%CI: 0.67–0.81) provided the highest AUC. Patients with positive pulse augmentation or arm elevation test should undergo DUS immediately for early detecting stenosis.