A circulatory model for combined nitroprusside-dopamine therapy in acute heart failure.

A computer model was developed to approximate the hemodynamic responses of dopamine and nitroprusside in acute left ventricular pump failure. The model is intended to aid the design of a multiple drug infusion system. A non-linear electrical analog model with baroreflex feedback was used to simulate the circulatory system. Heart failure was represented by a reduction in left ventricular inotropy. Pharmacodynamic relationships between the drugs studied and several elements of the system were incorporated into the model to simulate the overall drug responses which include secondary interactions between vascular components. Despite several shortcomings, the model showed good agreement with experimental and clinical data.