Design of computerized drug delivery control system

Abstract

Postsurgical complication of hypertension may occur in cardiac patients. This is particularly evident after coronary artery bypass grafting procedures. To decrease the chances of complication, it is necessary to reduce the elevated blood pressure as soon as possible. One of effective way is continuous infusion of vasodilator drugs, such as sodium nitroprusside (SNP), which will quickly lower the blood pressure in most patients. However, it is observed that a wide range of patient drug sensitivities to SNP occurs and also, critical patient care often requires the infusion of blood, fluid, or drugs to regulate cardiovascular system variables. Even though manual control by clinical personnel could be very tedious, time consuming and inconsistent, it is the current situation. It is believed therefore, that automation of these therapies by application of feedback control techniques can be effective. In this project, we propose some control methods to regulate the infusion rate of vasodilator drug so that the desired mean arterial pressure can be reached. An adaptive control algorithm based on generalized predictive control is designed. Following that, a new PI controller is proposed and a new control criterion for switching from one controller to another has been introduced.