Evaluation of the implementation of a fully automated algorithm (eMPC) in an interacting infusion pump system for the establishment of tight glycaemic control in medical ICU patients

Introduction

The purpose of this study was to investigate the performance of a newly developed prototype decision support system for the establishment of tight glycaemic control in patients in the medical ICU for a period of 72 hours.

Methods

The study was conducted as a single-center, open, noncontrolled clinical investigation in 10 mechanically ventilated patients at the Medical University Graz. After admittance to the ICU, arterial blood glucose values were monitored and the CS-1 Decision Support System (interacting infusion pumps with integrated algorithm eMPC and user interface) was used to adjust the infusion rate of intravenously administered human soluble insulin to normalize arterial blood glucose. The efficacy and safety were assessed by calculating the percentage within the target range (4.4–6.1 mM), the hyperglycaemic index (HGI), mean glucose and the number of hypoglycaemic episodes (<2.2 mM).

Results

The percentage of readings within the target range was 47.0% (± 13.0). The average blood glucose concentration and HGI were 6.08 mM (± 0.73) and 0.54 mM (± 0.52), respectively. No hypoglycaemic episode (<2.2 mM) was detected. Several technical malfunctions of the device, such as repetitive error messages and missing data in the data log owing to communication problems between the new hardware components, are shortcomings of the present version of the device. Owing to these technical failures of system integration, treatment had to be stopped ahead of schedule in three patients.

Conclusion

For the first time a decision support system fully integrated into an infusion pump system was tested clinically. Despite technical malfunctions, the performance of this prototype system of the CS-1 Decision Support System device was, from a clinical point of view, already effective in maintaining tight glycaemic control. Accordingly, and with technical improvement required, the CS1 system has the capacity to be further improved in the next phase of the development process and to serve as a reliable tool for routine establishment of glycaemic control for critically ill patients.