Hemodynamic changes during hemodialysis: role of dialyzate

To determine the contribution of the dialyzate to the hemodynamic changes that occur during hemodialysis, echocardiographic measurements obtained during identical conditions of hemodialysis except for the use of different dialyzates were compared. With an acetate-buffer systolic blood pressure and arterial oxygen tension declined but mean rate of left ventricular fiber shortening increased. These changes occurred after only 15 min of hemodialysis. By contrast, with a bicarbonate buffer these alterations did not ensue. Thus, during hemodialysis with limited ultrafiltration, the fall in arterial pressure observed is caused by the acetate-buffer. In hemodynamically unstable patients, bicarbonate may be the preferable dialyzate.