BACKGROUND: Routine access flow (AF) surveillance is recommended by the Kidney Disease Outcomes Quality Initiative as one of several components for an arteriovenous vascular access maintenance program. A reliable, but affordable, measurement tool is needed for outpatient hemodialysis facilities. STUDY DESIGN: Diagnostic test study. SETTING & PARTICIPANTS: 50 adult patients with 27 grafts and 23 fistulas from a single center who consented to sequential AF measurements, all performed within the first 90 minutes of the hemodialysis treatment. INDEX TEST: AF measured by using online conductivity dialysance (OLC-AF). REFERENCE TEST: AF measured by using ultrasound dilution (UD-AF). RESULTS: Mean UD-AF was 1,086 +/- 629 mL/min, and mean OLC-AF was 951 +/- 575 mL/min, with a mean difference of 135 +/- 229 mL/min. OLC-AF correlated significantly with UD-AF (0.93; P < 0.0001), becoming tighter for flows less than 1,000 mL/min (0.95; P < 0.0001). The coefficient of variation for sequential measurement by using UD was 6.4%, and for OLC, 11.5%, with the difference becoming insignificant (7.6% versus 8.8%; P = 0.5) for flows less than 1,000 mL/min. The average of 2 sequential UD-AF measurements correlated tightly with that of OLC-AF (0.99; P < 0.0001). LIMITATIONS: Tests were performed by 2 highly trained coordinators in a single clinic with a small sample size, and clinical outcomes were not evaluated. CONCLUSION: The OLC method is a reasonable alternative to UD for flow surveillance of arteriovenous hemodialysis accesses and provides an option for widespread implementation of a vascular access surveillance program. Additional studies are needed to determine whether routine use impacts on clinical outcomes.
BACKGROUND: Routine access flow (AF) surveillance is recommended by the Kidney Disease Outcomes Quality Initiative as one of several components for an arteriovenous vascular access maintenance program. A reliable, but affordable, measurement tool is needed for outpatient hemodialysis facilities. STUDY DESIGN: Diagnostic test study. SETTING & PARTICIPANTS: 50 adult patients with 27 grafts and 23 fistulas from a single center who consented to sequential AF measurements, all performed within the first 90 minutes of the hemodialysis treatment. INDEX TEST: AF measured by using online conductivity dialysance (OLC-AF). REFERENCE TEST: AF measured by using ultrasound dilution (UD-AF). RESULTS: Mean UD-AF was 1,086 +/- 629 mL/min, and mean OLC-AF was 951 +/- 575 mL/min, with a mean difference of 135 +/- 229 mL/min. OLC-AF correlated significantly with UD-AF (0.93; P < 0.0001), becoming tighter for flows less than 1,000 mL/min (0.95; P < 0.0001). The coefficient of variation for sequential measurement by using UD was 6.4%, and for OLC, 11.5%, with the difference becoming insignificant (7.6% versus 8.8%; P = 0.5) for flows less than 1,000 mL/min. The average of 2 sequential UD-AF measurements correlated tightly with that of OLC-AF (0.99; P < 0.0001). LIMITATIONS: Tests were performed by 2 highly trained coordinators in a single clinic with a small sample size, and clinical outcomes were not evaluated. CONCLUSION: The OLC method is a reasonable alternative to UD for flow surveillance of arteriovenous hemodialysis accesses and provides an option for widespread implementation of a vascular access surveillance program. Additional studies are needed to determine whether routine use impacts on clinical outcomes.