title: Comparison of hemodialysis access flow measurements using flow dilution and in-line dialysance.
abstract: Measurement of hemodialysis (HD) access flow (QA) is a noninvasive approach for arteriovenous graft or fistula surveillance. Flow dilution (FD) and in-line dialysance (DD) are two common methods for measuring QA. In a randomized fashion, we prospectively evaluated QA using FD and DD in 48 HD patients during three separate HD sessions over a span of 3 months. The measurement of QA was similar (1,016 +/- 412 ml/min for FD and 1,009 +/- 425 ml/min for DD, p = 0.44 and 0.79 for the mean and standard deviation, respectively). While FD successfully measured QA >or=2,000 ml/min, DD "saturated" (indicating a QA >or=2,000 ml/min without providing a numerical QA value) (n = 17). The correlation coefficient for QA <or=2,000 ml/min between DD and FD measurements from the same dialysis sessions was high (r = 0.9, p < 0.001) with a straight line slope of 0.997. Access flow values for FD and DD methods were comparable at QA <or=2,000 ml/min and no single method tended to over- or underestimate QA compared with the other. For QA >2,000 ml/min, FD provided a quantitative QA measure, and is therefore a potentially useful tool for QA above this threshold, while DD is not.
authors.affiliation: Department of Internal Medicine, Division of Nephrology, Rush University Medical Center, Chicago, Illinois 60607, USA. william_whittier@rush.edu
authors.forename: William L
authors.initials: WL
authors.lastname: Whittier
authors.forename: Hansen A
authors.initials: HA
authors.lastname: Mansy
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Rutz
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Lewis
authors.forename: Richard H
authors.initials: RH
authors.lastname: Sandler
mesh_terms: D000368:Aged; D001166:Arteriovenous Shunt, Surgical / Q000379:methods; D003251:Constriction, Pathologic / Q000209:etiology; D005260:Female; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007676:Kidney Failure, Chronic / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D006435:Renal Dialysis / Q000379:methods*; D013927:Thrombosis / Q000209:etiology; D018608:Ultrasonography, Doppler / Q000379:methods
chemical_list: D005947:Glucose