An adaptive control system for delivering heparin to provide anticoagulation during hemodialysis

This paper describes an adaptive control system for delivering heparin to maintain a desired level of anticoagulation during hemodialysis. Adaptive control was based on sparse measurements of the activated clotting time (ACT) measured in blood samples drawn from the extracorporeal circuit. A model-based control law was used in conjunction with Bayesian parameter estimation in the adaptive control system. The adaptive control system was validated in clinical trials during a routine 240-minute hemodialysis procedure. The mean of ACT values measured during adaptive control was 150 percent of the baseline ACT and the standard deviation was 11 percent.