A method of performing regional citrate anticoagulant dialysis of a patient's blood includes flowing blood from and back to the patient through an extracorporeal circuit including a dialyzer having semi-permeable dialysis membranes and a dialysate chamber surrounding the membranes. The method further includes flowing a dialysate containing calcium and citrate through the dialysate chamber of the dialyzer and introducing citrate into the patient's blood upstream of the dialyzer, whereby the patient's blood is dialyzed. The method can further include predicting the concentration of systemic ionized calcium in the blood of the patient at any point in the dialysis treatment or post-dialysis, such as by a mathematical model. The method can further include statistically correcting the preliminary predicted post-dialysis concentration of systemic ionized calcium in the patient's blood to provide a final predicted post-dialysis systemic ionized calcium concentration. The method can further include statistically correcting the preliminary predicted systemic ionized calcium concentration for any time point during the dialysis treatment to provide a final predicted systemic ionized calcium concentration for that time point.
