Flow measurement in dialysis shunts.
نویسندگان
چکیده
Sir, In a recent technical note, Zanen et al. reported poor agreement between different Doppler flow measurements in dialysis shunts, such as conventional Doppler (CD), quantitative colour velocity index (CVI-Q) and ultrasound dilution (DU) w1x. In particular, results of CD measurements did not correlate with those obtained with CVI-Q and DU, respectively. We share the experience of the investigators that values of measured blood flow vary between different commercial Doppler ultrasound systems. We found that flow measurements differ between machines and even between different ultrasound probes with the same machine w2x. Therefore absolute values of measured blood flow volume should be interpreted with caution. Blood flow (Qb) (flow volumeumin) is calculated by the cross sectional area of the vessel (A) and the time average velocity (TAV) according to the formula:
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ورودعنوان ژورنال:
- Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association
دوره 16 12 شماره
صفحات -
تاریخ انتشار 2001