RESUMO
To evaluate the feasibility and accuracy of contrast-enhanced ultrasonography (CEUS) for the measurement of hemodialysis access recirculation (AR) and access flow rate (Qa), a two pump system was used to simulate access and dialyzer flow. AR and Qa under different conditions, such as reversal connection of dialysis lines and the needle orientation, were compared with each other. The value of access flow and recirculation flow were calculated based on the formulas introduced in this paper, and the correlation and consistency between true flow rate and calculated values were analyzed. The measured R correlated well with true value of flow rate (r = 0.57, P = 0.038, Qa > Qb; r = 0.95, P = 0.001, Qa < Qb). The Bland-altman test showed good agreement between the calculated value based on CEUS and true values. The CEUS can be used as a new advanced technology for AR and Qa measurement.