Novel blood sampling method of an artificial endocrine pancreas via the cardiopulmonary bypass circuit

Artificial endocrine pancreas with a closed-loop system effectively suppresses the accelerated hyperglycemic status after reperfusion during aortic surgery

OBJECTIVES

To control intraoperative hyperglycemia in patients who underwent aortic surgery using STG-55^® artificial endocrine pancreas and clarify the effectiveness of this device.

METHODS

Blood glucose control using the STG-55^® was performed in 18 patients (15 men and 3 women; age, 66 ± 10 years) who required hypothermic circulatory arrest (STG-55^® group). Seventeen patients (10 men and 7 women; age, 71 ± 8 years) whose blood glucose was controlled using the conventional method were included in the control group. Glucose concentration was controlled with the aim of maintaining it at 150 mg/dl.

RESULTS

In both groups, the blood glucose concentrations did not significantly change during the interruption of systemic perfusion; however, a sharp increase was noted immediately after reperfusion. Although the hyperglycemic status persisted after reperfusion in the control group, it was effectively suppressed in the STG-55^® group (STG^® vs. control group at 50 min after reperfusion: 180 ± 35 vs. 212 ± 47 mg/dl, p = 0.026) and blood glucose concentration reached the target value of 150 mg/dl at 100 min after reperfusion (STG^® vs. control group: 153 ± 29 vs. 215 ± 43 mg/dl, p = 0.0008). The total administered insulin dose was 175 ± 81 U and 5 ± 3 U in the STG^® and control groups, respectively (p < 0.0001).

CONCLUSIONS

To treat the accelerated hyperglycemic status in aortic surgery requiring circulatory arrest, strict glycemic control using an artificial endocrine pancreas might be beneficial.

Impact of newly developed, next-generation artificial endocrine pancreas

BACKGROUND

Recent studies have shown that strict perioperative blood glucose management may reduce mortality and morbidity in critically ill adult patients. The purpose of this study was to assess the accuracy and efficacy of the intraoperative application of a newly developed, next-generation artificial endocrine pancreas (STG-55, Nikkiso Co., Ltd., Tokyo, Japan).

METHODS

Twenty patients scheduled to undergo surgery were enrolled in this study. The STG-55 is designed to be more user-friendly than its conventional counterpart (STG-22) while maintaining the latter's fundamental functions, such as a closed-loop system using algorithms for insulin and glucose infusion. After anesthetic induction, a 20G intravenous catheter was inserted into a peripheral forearm vein and connected to a continuous blood glucose monitor. The resultant 105 scores for paired blood glucose values were compared by Bland-Altman analysis.

RESULTS

Stable blood glucose values were maintained automatically, and there were no complications related to use of the STG-55. A close correlation (r=0.96) was observed between continuous glucose measurements using the STG-55 and conventional intermittent glucose measurements. The difficulty of manipulation using this system was decreased by improved preparation procedures.

CONCLUSION

The glycemic control system using the STG-55 could provide an alternative way to achieve effective and safe perioperative glycemic control.