The Accuracy Benefit of Multiple Amperometric Glucose Sensors in People With Type 1 Diabetes

Department of Medicine, Division of Endocrinology, Diabetes & Clinical Nutrition, Oregon Health & Science University, Portland, Oregon, USA.
Diabetes care (Impact Factor: 8.57). 02/2012; 35(4):706-10. DOI: 10.2337/dc11-1929
Source: PubMed

ABSTRACT To improve glucose sensor accuracy in subjects with type 1 diabetes by using multiple sensors and to assess whether the benefit of redundancy is affected by intersensor distance.
Nineteen adults with type 1 diabetes wore four Dexcom SEVEN PLUS subcutaneous glucose sensors during two 9-h studies. One pair of sensors was worn on each side of the abdomen, with each sensor pair placed at a predetermined distance apart and 20 cm away from the opposite pair. Arterialized venous blood glucose levels were measured every 15 min, and sensor glucose values were recorded every 5 min. Sensors were calibrated once at the beginning of the study.
The use of four sensors significantly reduced very large errors compared with one sensor (0.4 vs. 2.6% of errors ≥50% from reference glucose, P < 0.001) and also improved overall accuracy (mean absolute relative difference, 11.6 vs. 14.8%, P < 0.001). Using only two sensors also significantly improved very large errors and accuracy. Intersensor distance did not affect the function of sensor pairs.
Sensor accuracy is significantly improved with the use of multiple sensors compared with the use of a single sensor. The benefit of redundancy is present even when sensors are positioned very closely together (7 mm). These findings are relevant to the design of an artificial pancreas device.

  • [Show abstract] [Hide abstract]
    ABSTRACT: This study details the use of printing and other additive processes to fabricate a novel amperometric glucose sensor. The sensor was fabricated using a Au coated 12.7 micron polyimide film as a starting material, where micro-contact printing, electrochemical plating and chloridization, electrohydrodynamic jet (e-jet) printing, and spin coating were used to pattern, deposit, print, and coat functional materials, respectively. We have found that e-jet printing was effective for the deposition and patterning of glucose oxidase inks between ~5 to 1000 micron in width, and we have demonstrated that the enzyme was still active after printing. The thickness of the permselective layer was optimized to obtain a linear response to glucose concentration up to 32 mM. For these sensors no response to acetaminophen, a common interfering compound, was observed.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Introduction: Insulin pump technology has advanced considerably over the past three decades, leading to more favorable metabolic control and less hypoglycemic events when compared with multiple daily injection therapy. The use of insulin pumps is increasing, particularly in children and adolescents with type 1 diabetes. Areas covered: This review outlines recent developments in insulin pump therapy from a pediatric perspective. 'Smart' pumps, sensor-augmented pump therapy and threshold-suspend feature of insulin pumps are reviewed in terms of efficacy, safety and psychosocial impact. The current status of closed-loop systems focusing on clinical outcomes is highlighted. Expert opinion: Closed-loop insulin delivery is gradually progressing from bench to the clinical practice. Longer and larger studies in home settings are needed to expand on short- to medium-term outpatient evaluations. Predictive low glucose management and overnight closed-loop delivery may be the next applications to be implemented in daily routine. Further challenges include improvements of control algorithms, sensor accuracy, duration of insulin action, integration and size of devices and connectivity and usability. Gradual improvements and increasing sophistication of closed-loop components lie on the path toward unsupervised hands-off fully closed-loop system.
    Expert Opinion on Drug Delivery 04/2014; DOI:10.1517/17425247.2014.910192 · 4.12 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The development of a closed-loop “artificial pancreas” would be a welcome advance for both endocrinologists and diabetic patients struggling to attain near normal glycemic control. While great strides in automatically controlling blood sugar in the fasting, sedentary state have been made through complex mathematical modeling, management of blood sugar excursions due to food and exercise have been more problematic. An artificial pancreas is not feasible at this time because of limitations inherent in the currently available technology. 摘要 为了达到接近正常的血糖控制的目标,内分泌学家与糖尿病患者都在不断地努力,而研制出一种闭环的“人工胰腺”对于他们来说将是一个可喜的进步。虽然通过复杂的数学模型在自动控制空腹与久坐状态的血糖方面已经取得了巨大的进展,但是如何处理饮食与运动所导致的血糖偏移却是个更大的问题。因为当前可用技术固有的局限性,目前人工胰腺并不可行。
    Journal of Diabetes 09/2013; 5(3). DOI:10.1111/1753-0407.12052 · 2.35 Impact Factor

Full-text (3 Sources)

Available from
Feb 27, 2015