Identifying a new reality: zero vascular access recirculation using ultrasound dilution

Access recirculation measurements by blood urea nitrogen (BUN) sampling methods have come under recent criticism regarding their reliability especially at low levels of recirculation. New methods have shown that the majority of patients have much less recirculation than previously suspected. However, some of these methods are prone to the same factors that limit BUN measurement accuracy. A new method, ultrasound dilution, was studied that avoids these problems and supports a new clinical reality--zero access recirculation. Information on the relationship of recirculation to access flow was also obtained which supports the assumption that patients with adequate vascular access flows have no recirculation.