Abstract
In the mid-nineties, the first vascular access blood flow (QVA) measurement at the bedside has been developed, based on measurement of forced recirculation at inverted needles by ultrasonic dilution. Prophylactic QVA measurement soon became the method of choice in regular vascular access status assessment.
Since 2016, this procedure is also reimbursed by all insurance companies in the Czech Republic. Subsequently, number of alternative methods of QVA evaluation was developed, mostly but not exclusively based on dilutional techniques.
The article describes all those methods, their principles (ultrasonic dilution, thermodilution, optodilution/optoconcentration, ionic dialysance, conductivity step-wise change, conventional duplex-doppler and sole doppler velocity measurement), technical and performance pros and cons as well as technical means needed for practical implementation.