Use of A Continuous Glucose Monitor in the Management of Inoperable Meta Static Insulinoma: A Case Report

ObjectiveTo describe the successful use of a continuous glucose monitor in the management of a patient with inoperable metastatic insulinoma.MethodsWe present a case of inoperable recurrent metastatic insulinoma in which medical therapy failed to relieve symptoms of dangerous hypoglycemia. We describe how the use of a continuous glucose monitor has assisted in avoiding hypoglycemia and improving her quality of life.ResultsA 70-year-old woman with a history of recurrent surgically treated insulinoma presented with recurrent hypoglycemia secondary to multiple metastases in the liver. Diazoxide therapy decreased the frequency of symptoms, but she continued to have hypoglycemic episodes resulting in frequent visits to the emergency department. Since starting to use a continuous glucose monitor, she has been able to avoid hypoglycemia with associated neuroglycopenic symptoms. While the accuracy of the device was poor when compared with conventional fingerstick monitors, the sensor tended to read higher than the meter in the hypoglycemic range. Although this led to more frequent false-positive hypoglycemic alarms, true episodes of severe hypoglycemia were rare.ConclusionsMalignant insulinomas are rare tumors. Many affected patients have disease that is unresectable, and medical therapy is limited in its ability to prevent hypoglycemic episodes. We have demonstrated that a continuous glucose monitor can be a useful adjunct to therapy to reduce hypoglycemic episodes by alerting the patient to low glucose concentrations before the development of neuroglycopenic symptoms. (Endocr Pract. 2008;14:880-883)     

Clinical Use of the Glucose Disappearance Rate

An intravenous glucose tolerance test, coupled with a graphical or mathematical analysis, has been used in normal, diabetic, and glycosuric subjects, and patients suspected of having hypoglycemia. From the analysis, a single value, K, is derived which integrates the disappearance of the injected glucose. A significant difference was found between normals and known diabetics: this difference becomes even more distinct when the disappearance of the glucose load is measured as K1 or Increment Index, as opposed to decrease of the total blood glucose, K2 or Total Index. A 300-g. carbohydrate diet was shown to be important to the success of this test. More than 400 patients have been tested in the investigation of different disorders of glucose metabolism. Renal glycosuria was diagnosed in 35 patients. Rapid disappearance of the glucose load has been observed in 18 of 40 patients suspected of having hypoglycemia. Of 64 patients diagnosed in the hospital as previously unknown diabetics, 59 presented K1 values below the normal range.     

Perception of Graduating Endocrinology,Diabetes, and Metabolism Fellows on the Benefits of Wearing A Continuous Glucose Monitor and/or Insulin Pump for Their Education

Objectives: To our knowledge, no prior research has explored the prevalence of wearing continuous glucose monitors (CGMs) and/or insulin pumps among in-training fellows and their perception of doing so as part of their education. Our objectives therefore were to estimate the frequency with which wearing a CGM and/or insulin pump is used as a learning opportunity and explore the main motivators and perception on its value.Methods: A multiple-choice survey that addressed each fellow's level of training, type of fellowship training program, and use of CGM and/or insulin pump was sent to all Accreditation Council for Graduate Medical Education endocrinology, diabetes, and metabolism program coordinators or program directors. We asked them to forward this survey to their graduating fellows. Their perception on the value of wearing these devices was addressed.Results: Fifty-one graduating fellows responded to the survey; 78.43% and 62.5% of them wore a CGM and insulin pump, respectively. A total of 89.48% and 90% of those who wore a CGM and insulin pump, respectively, thought it was above-average value for their education, and the most common reasons were to learn the technical aspects and understand what patients with diabetes go through.Conclusion: Wearing a CGM and/or insulin pump is perceived by endocrinology graduating fellows as valuable to their education, specifically, to learn the technical aspects, understand the patient's experience, and develop empathy.Abbreviations: ACGME = Accreditation Council for Graduate Medical Education; CGM = continuous glucose monitor     

血糖检测仪在社区医疗中的应用分析

目的探讨社区医疗中血糖检测仪的应用。方法分析2010年1月～2010年10月在社区使用血糖仪的2型糖尿病患者30例,定期检测糖尿病患者的血糖控制情况,并进行健康教育。结果与同期未进行定期测量血糖的30例糖尿病患者比较,血糖控制情况差异有统计学意义。结论社区血糖检测仪应用方便,对实时检测糖尿病患者的血糖有较好的诊断价值,值得在社区广泛使用。     

Frequency of Continuous Glucose Monitoring use and Change in Hemoglobin A1C for Adults With Type 1 Diabetes in a Clinical Practice Setting

ObjectiveTo estimate the frequency of continuous glucose monitoring (CGM) use and change in hemoglobin A1c (HbA1c) compared to self-monitoring of blood glucose (SMBG) alone in adults with type 1 diabetes in a clinical practice setting.MethodsWe retrospectively identified 66 adult type 1 diabetes patients at the Barbara Davis Center for Diabetes (BDC) who first initiated CGM between 2006 and 2011 and 67 controls using SMBG. The frequency of CGM use was estimated from survey recall and defined as the mean number of days/month of CGM use during a maximum follow-up of 10 months. Change in HbA1c was calculated as the difference between the baseline value and the lowest follow-up value.ResultsThe mean change in HbA1c for CGM users was − 0.48% (95% confidence interval [CI]: − 0.67, − 0.28) and for SMBG users was − 0.37% (95% CI: − 0.56, − 0.18). The between-group mean difference in change in HbA1c, adjusted for patient characteristics, was − 0.11% (95% CI: − 0.38, 0.16), whereas the subgroup with a baseline HbA1c ≥ 7.0% and users of CGM ≥ 21 days/month was − 0.36% (95% CI, − 0.78, 0.05). Nearly half (n = 32, 48%) used CGM < 21 days/month. The reasons for low frequency of CGM use or discontinuation included sensor costs, frequency of alarms, inaccuracy, and discomfort.ConclusionsThese CGM data from clinical practice suggest a trend toward decreasing HbA1c for adults with type 1 diabetes, especially in patients with higher baseline HbA1c and higher frequency of CGM use. Future studies are needed to assess the use of CGM in larger populations of clinical practice adult type 1 diabetes patients. (Endocr Pract. 2014;20:1007-1015)     

Expert Roundtable on Continuous Glucose Monitoring

ObjectiveThe objective of this study was to define an expert opinion on continuous glucose monitoring (CGM) in persons with type 2 diabetes mellitus, including its advantages, barriers, and best clinical practices for initiation, patient-clinician communication, and data management.MethodsA series of virtual discussions was held to recommend improvements to clinical practice and design clinical tools for primary care clinicians. Participants included endocrinologists, primary care physicians, physician assistants, advanced practice nurses, and diabetes care and education specialists.ResultsThe expert panels recommended CGM as a supplement to blood glucose monitoring and hemoglobin A1c for managing diabetes in persons with diabetes (PWDs). CGM can help predict potential pitfalls in glycemic management, including hypo and hyperglycemic excursions, which directly influence lifestyle changes, medication initiation, and dosing decisions. A toolkit was designed with practical guidance on the integration of CGM into clinical practice, interpretation of results, clinical guidelines, a patient action plan, and other useful management tools.ConclusionThis review summarizes the findings from a roundtable discussion with endocrinology and primary care clinicians, a discussion of the advantages and challenges of CGM, and clinical approaches to improving the care of PWDs. CGM offers more detailed tracking of glucose levels than blood glucose monitoring or hemoglobin A1c, and it can detect asymptomatic hypoglycemia. Specialized education of providers, the cost to patients and providers, and data management are barriers to the widespread adoption of CGM for PWDs.     

Accuracy of Continuous Glucose Monitoring Measurements in Normo-Glycemic Individuals

BackgroundThe validity of continuous glucose monitoring (CGM) is well established in diabetic patients. CGM is also increasingly used for research purposes in normo-glycemic individuals, but the CGM validity in such individuals is unknown. We studied the accuracy of CGM measurements in normo-glycemic individuals by comparing CGM-derived versus venous blood-derived glucose levels and measures of glycemia and glycemic variability.MethodsIn 34 healthy participants (mean age 65.7 years), glucose was simultaneously measured every 10 minutes, via both an Enlite^® CGM sensor, and in venous blood sampled over a 24-hour period. Validity of CGM-derived individual glucose measurements, calculated measures of glycemia over daytime (09:00h-23:00h) and nighttime (23:00h-09:00h), and calculated measures of glycemic variability (e.g. 24h standard deviation [SD]) were assessed by Pearson correlation coefficients, mean absolute relative difference (MARD) and paired t-tests.ResultsThe median correlation coefficient between CGM and venous glucose measurements per participant was 0.68 (interquartile range: 0.40–0.78), and the MARD was 17.6% (SD = 17%). Compared with venous sampling, the calculated measure of glycemia during daytime was 0.22 mmol/L higher when derived from CGM, but no difference was observed during nighttime. Most measures of glycemic variability were lower with CGM than with venous blood sampling (e.g., 24h SD: 1.07 with CGM and 1.26 with venous blood; p-value = 0.004).ConclusionIn normo-glycemic individuals, CGM-derived glucose measurements had good agreement with venous glucose levels. However, the measure of glycemia was higher during the day and most measures of glycemic variability were lower when derived from CGM.     

Continuous Quality Improvement in Daily Clinical Practice: A Proof of Concept Study

Continuous Quality Improvement (CQI) is an iterative process of: planning to improve a product or process, plan implementation, analyzing and comparing results against those expected, and corrective action on differences between actual and expected results. It is little used in clinical medicine. Anemia, a complex problem in End Stage Renal Disease patients, served to test the ability of an unique electronic medical record (EMR) optimized for daily care to empower CQI in practice. We used data collected during daily care, stored in the EMR, and organized to display temporal relationships between clinical, laboratory, and therapeutic events. Our aims were optimal hemoglobin with minimum epoetin, and maintaining stable hemoglobin and epoetin. The study was done on 250 patients treated by maintenance hemodialysis (HD), receiving epoetin prior to February 1, 2010 and followed to July 31, 2011. Repleting iron, ensuring iron sufficiency, slow epoetin reduction, and decision support tools enabling data display over long periods in patient-centered reports were key elements. Epoetin dose, adjusted 6–8 weekly, was based on current clinical conditions and past responses. Hemoglobin increased by months 1–2; epoetin decreased from month 4. By months 16–18, epoetin had decreased 42% to 9,720 units/week while hemoglobin increased 8% to 123.6 g/L. Hemoglobin and epoetin were stable from month 7 onward. New epoetin orders decreased 83%. Transferrin saturation increased after the study start. Individual patient hemoglobin variation decreased by 23%, range by 27%. Mortality, 11.78 per 100 patient years, was 42% less than United States dialysis patient mortality. Allowable epoetin charges decreased by $15.33 per treatment and were $22.88 less than current Medicare allowance. The study validates the hypothesis that an EMR optimized for daily patient care can empower CQI in clinical medicine and serve to monitor medical care quality and cost.     

Use of Electrical Impedance Tomography to Monitor Regional Cerebral Edema during Clinical Dehydration Treatment

Objective

Variations of conductive fluid content in brain tissue (e.g. cerebral edema) change tissue impedance and can potentially be measured by Electrical Impedance Tomography (EIT), an emerging medical imaging technique. The objective of this work is to establish the feasibility of using EIT as an imaging tool for monitoring brain fluid content.

Design

a prospective study.

Setting

In this study EIT was used, for the first time, to monitor variations in cerebral fluid content in a clinical model with patients undergoing clinical dehydration treatment. The EIT system was developed in house and its imaging sensitivity and spatial resolution were evaluated on a saline-filled tank.

Patients

23 patients with brain edema.

Interventions

The patients were continuously imaged by EIT for two hours after initiation of dehydration treatment using 0.5 g/kg intravenous infusion of mannitol for 20 minutes.

Measurement and Main Results

Overall impedance across the brain increased significantly before and after mannitol dehydration treatment (p = 0.0027). Of the all 23 patients, 14 showed high-level impedance increase and maintained this around 4 hours after the dehydration treatment whereas the other 9 also showed great impedance gain during the treatment but it gradually decreased after the treatment. Further analysis of the regions of interest in the EIT images revealed that diseased regions, identified on corresponding CT images, showed significantly less impedance changes than normal regions during the monitoring period, indicating variations in different patients'' responses to such treatment.

Conclusions

EIT shows potential promise as an imaging tool for real-time and non-invasive monitoring of brain edema patients.     

Evaluation of Insulin Glargine and Exenatide Alone and in Combination: a Randomized Clinical Trial with Continuous Glucose Monitoring and Ambulatory Glucose Profile Analysis

Objective: Characterize the effectiveness of insulin glargine alone, exenatide alone, or combined in subjects taking stable doses of metformin and evaluate their impact on hemoglobin A1C, hypoglycemia, weight, and glucose variability.Methods: Open-label, randomized, parallel-arm study of adults with type 2 diabetes naïve to both insulin and glucagon-like peptide 1 (GLP-1) agonist who were not at A1C goal despite treatment with metformin. This prospective interventional study employed blinded continuous glucose monitoring ambulatory glucose profile (AGP) reports over 32 weeks. Subjects were randomized to treatment with glargine (Iglar), exenatide (GLP-1), or combination of glargine and exenatide (Iglar + GLP-1). At midpoint, those not at A1C target had the second medication added; those on Iglar + GLP-1 continued therapy optimization.Results: Decreases in A1C were: 7.6 to 6.2% for Iglar + GLP-1, 7.5 to 6.6% for Iglar, and 7.5 to 6.4% for GLP-1. Iglar + GLP-1 achieved A1C targets faster (14 to 16 weeks) but had more hypoglycemia. Hypoglycemia rates increased slightly for all arms. Weight loss was achieved in all regimens including GLP-1. Glucose variability was not reduced to the same extent in the Iglar arm as the GLP-1 arm.Conclusion: Addition of Iglar and/or GLP-1 to metformin for patients not at treatment goal was safe and effective. The order of medication addition needs to consider individualized AGP patterns and goals. Iglar + GLP-1 resulted in rapid A1C lowering, whereas GLP-1 was noted to have less hypoglycemia. Weight loss was most pronounced in GLP-1 monotherapy, suggesting that GLP-1 may mitigate the weight gain of Iglar. Any treatment with GLP-1 showed significant decreases in glucose variability.Abbreviations: A1C = hemoglobin A1c; AGP = ambulatory glucose profile; CGM = continuous glucose monitoring; GLM = general linear model; GLP-1 = glucagon-like peptide 1 (exenatide); Iglar = insulin glargine; SGLT2 = sodium-glucose cotransporter 2; SMBG = self-monitoring blood glucose; SU = sulfonylurea; T2D = type 2 diabetes mellitus     

A Double-Needle Gold-Silver Electrodes Continuous Glucose Monitoring Device

ObjectivesDiabetes is a serious, long-term disease and the use of continuous glucose monitoring sensors can reduce reliance on other painful invasive blood testing methods such as the finger blood glucose test. According to our work, a low-cost continuous glucose sensor has been developed based on electrochemical measurement techniques.MaterialsThe sensor is based on a two needles system; a gold and a silver electrode are integrated into a circular shaped electronic printed circuit board (PCB). The sensing part is based on biological electrochemical measurements. Glucose oxidase (Gox) was used as the active sensing element and ferrocene (Fc) as a mediator. Simple and low-cost coating methods were used; these methods are self-assembled monolayers and deep coating. This will reduce the final cost of the sensor as no expensive technique was used. The electrical subsystem contains a low-noise and low-power trans-impedance front-end as well as a single-chip low-power Bluetooth microcontroller with a 12-bit Analog-to-Digital Converter (ADC).ResultsThe sensor was tested in various concentrations of glucose. As a result of initial in vitro experiments, detailed analytical performance metrics are presented. The device has consistently shown a sensitivity of 3.059 mV/(mg/dl) reading with a linear range of 0-400 mg/dl.ConclusionThe proposed study shows promising results for glucose detection. Thus, this type of sensor can be used for different analyzes targeting biological applications after further investigations and analysis.     

Continuous Glucose Monitoring in Patients Undergoing Extracorporeal Ventricular Assist Therapy

Background

Dysregulations of blood glucose (BG) are associated with adverse outcome in critical illness; controlling BG to target appears to improve outcome. Since BG-control is challenging in daily intensive care practice BG-control remains poor especially in patients with rapidly fluctuating BG. To improve BG-control and to avoid deleterious hypoglycemia, automated online-measurement tools are advocated. We thus evaluated the point-accuracy of the subcutaneous Sentrino^® Continuous Glucose Monitoring System (CGM, Medtronic Diabetes, Northridge, California) in patients undergoing extracorporeal cardiac life support (ECLS) for cardiogenic shock.

Methods

Management of BG was performed according to institute’s standard aiming at BG-levels between 100–145 mg/dl. CGM-values were recorded without taking measures into therapeutic account. Point-accuracy in comparison to intermittent BG-measurement by the ABL-blood-gas analyzer was determined.

Results

CGM (n = 25 patients) correlated significantly with ABL-values (r = 0.733, p<0.001). Mean error from standard was 15.0 mg/dl (11.9%). 44.2% of the readings were outside a 15% range around ABL-values. In one of 635 paired data-points, ABL revealed hypoglycemia (BG 32 mg/dl) whereas CGM did not show hypoglycemic values (132mg/dl).

Conclusions

CGM reveals minimally invasive BG-values in critically ill adults with dynamically impaired tissue perfusion. Because of potential deviations from standard, CGM-readings must be interpreted with caution in specific ICU-populations.     

Use of Flow Cytometry To Monitor Legionella Viability

Legionella viability was monitored during heat shock treatment at 70°C by a flow cytometric assay (FCA). After 30 min of treatment, for 6 of the 12 strains tested, the FCA still detected 10 to 25% of cells that were viable but nonculturable (VBNC). These VBNC cells were able to produce ATP and to be resuscitated after culture on amoebae.