Usefulness of continuous blood glucose monitoring and control for patients undergoing liver transplantation

Background : The purpose of this study was to evaluate the usefulness of the closed-loop system (STG-22 ; Nikkiso, Tokyo, Japan), a type of artificial endocrine pancreas for the continuous monitoring and control of intraoperative blood glucose in patients undergoing liver transplantation. Methods : Sixteen patients undergoing livingdonor liver transplantation were enrolled in this study. Glucose levels were controlled with either a manual injection of insulin based on a commonly used sliding scale (manual insulin group, n=8) or a programmed infusion of insulin determined by the control algorithm of the artificial endocrine pancreas (programmed insulin group, n=8). The target glucose level range was set at 80-150 mg/dl. Results : The mean and SD of blood glucose concentration during surgery (Glu-Ave and Glu-SD, respectively) for the programmed insulin group were lower than for the manual insulin group. The coefficient of variability (Glu-CV=Glu-SD×100 /Glu-Ave) for the programmed insulin group was also lower than for the manual insulin group (20.1±4.9% vs. 26.9±6.1% ; mean±SD). No hypoglycemia was detected in either group. Conclusion : The STG-22 closed-loop system is effective for maintaining strict blood glucose control during liver transplantation with minimal variability in blood glucose concentration

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

Usefulness of artificial endocrine pancreas during resection of insulinoma

A 71-year-old woman had an episode of syncope due to hypoglycemia of 27 mg/dl. She was diagnosed with insulinoma and scheduled for laparoscopic enucleation along with the use of an artificial endocrine pancreas (STG-22, Nikkiso Co., Ltd., Tokyo, Japan). Anesthesia was maintained with sevoflurane and remifentanil. Her blood glucose level was controlled using the artificial endocrine pancreas, which enabled continuous blood glucose monitoring and computer-operated glucose and insulin infusion to maintain the blood glucose level at a steady state. The target concentration of blood glucose was set at 80-120 mg/dl during surgery. Until removal of the tumor, the blood glucose level was kept at around 80-100 mg/dl. After removal of the tumor, the blood glucose level gradually increased, but it was kept in the normal range by the artificial endocrine pancreas. The artificial endocrine pancreas was useful to monitor and maintain blood glucose levels during and after the removal of insulinoma, without any hyper- or hypoglycemia

Stretchable Strain Sensor with Small but Sufficient Adhesion to Skin

Stretchable strain sensors that use a liquid metal (eutectic gallium–indium alloy; E-GaIn) and flexible silicone rubber (Ecoflex) as the support and adhesive layers, respectively, are demonstrated. The flexibility of Ecoflex and the deformability of E-GaIn enable the sensors to be stretched by 100%. Ecoflex gel has sufficiently large adhesion force to skin, even though the adhesion force is smaller than that for commercially available adhesives. This enables the sensor to be used for non-invasive monitoring of human motion. The mechanical and electrical properties of the sensor are experimentally evaluated. The effectiveness of the proposed sensors is demonstrated by monitoring joint movements, facial expressions, and respiration