The artificial pancreas, a challenge to research

The first attempts for automated glucose control were made in the seventies of the last century. Nowadays several prototypes for closed-loop glucose control are being tested, most of them in clinical research centers. Systems for automated glucose control, also named ‘artificial pancreas’ or ‘closed-loop system’ consist of three parts; the first part concerns the input or glucose measurement, the second part a mathematical model or control algorithm incorporated in a computer and the last part the output, delivery of glucose regulatory hormones, insulin and sometimes glucagon. For ambulatory human use, the system consists of subcutaneous continuous glucose monitor and subcutaneous administration of insulin and sometimes glucagon. In this thesis it is demonstrated that: - Administration of rapid-acting mealtime insulin 15 minutes before a meal resulted in better postprandial glucose control. - Mechanical occlusion of the infusion set of CSII should lead to an occlusion alert. The time to an alert differed per basal rate, length of the infusion catheter and the device. Furthermore: - A questionnaire was developed to test the intention to use the artificial pancreas. - Heart rate and acceleration as markers for exercise were used. No clear association between heart rate and acceleration and glucose values were seen because the study was too small. - Three different prototypes of a bihormonal reactive closed-loop were tested. Glucose control was feasible by using this closed loop system and significantly lower glucose values were seen in the last 24 hours of the third portable closed-loop prototype