Prospective evaluation of the intra-access flow of recently created native arteriovenous fistulae.

Background: The aim of this study is to assess the evolution of intra-access flow (Q(ac)) in recently created native arteriovenous fistulae (AVFs) during the first few months of use.

Methods: All AVFs were monitored by means of ultrasound dilution using Transonic (Transonic Systems Inc, Ithaca, NY). First Q(ac) measurements were obtained between 6 to 10 weeks after creation and subsequently every 3 to 6 weeks during the following 4 months.

Biofeedback regulation of ultrafiltration and dialysate conductivity for the prevention of hypotension during hemodialysis.

Intradialytic hypotension remains a frequent complication of dialysis, occurring in up to 33% of patients. We tested a fully integrated biofeedback system (the Hemocontrol system) that monitors and regulates blood volume contraction during hemodialysis. Seven hypotension prone patients were selected for the study.