¹Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand

Correspondence: S Eiam-Ong, Division of Nephrology, Department of Medicine, Faculty of Medicine, Chulalongkorn University Hospital, Bangkok 10330, Thailand. E-mail: Somchai80754@yahoo.com

Received 29 August 2007; Revised 11 November 2007; Accepted 27 November 2007; Published online 13 February 2008.

Abstract

Measurement of the vascular access flow rate (Q_a) is a widely accepted method for surveillance and predicting access failure. Among current practical methods, the ultrasound dilution technique is standard, but this requires a costly device available in few hemodialysis (HD) centers. Here, we devised a simple hemoglobin dilution technique to accurately measure Q_a without the need for any special machines. Before HD, values of Q_a were determined in each of 30 patients by hemoglobin dilution and then, in the same session, by ultrasound dilution. There was a significant correlation between the two techniques using automated hemoglobin and hematocrit or centrifuge-measured hematocrit levels to calculate HD fluid-derived Q_a values. Our study shows that the HD dilution technique, using no special device, is economical, highly accurate, and easy to perform, and can be used as an alternative to standard ultrasound dilution for vascular access surveillance.