bluuebunny/crossref_metadata_2025_split huggingface dataset:
Continuous Glucose Monitoring System in a Rural Intensive Care Unit: A Pilot Study Evaluating Accuracy and Acceptance
Authors: Jacobs Brooke , Phan Kim , Bertheau Leonard , Dogbey Godwin , Schwartz Frank , Shubrook Jay 
Published: January 2014

Background: Glucose management in an intensive care unit (ICU) is labor-intensive. A continuous glucose monitoring system (CGMS) has the potential to improve efficiency and safety in this setting. The goal of this study was to determine if the Medtronic Guardian® REAL-Time CGMS was accurate and tolerated by patients in a rural hospital ICU unit. Method: Differences between individual finger stick blood glucose (FSBG) and CGMS values were compared to American Diabetes Association (ADA) and International Organization for Standardization (ISO) standards. Continuous glucose monitoring system accuracy was evaluated over four ranges: <75, 75–140, 140–200, and >200 mg/dl. Other accuracy measures [mean absolute deviation (MAD), mean absolute relative difference (MARD), and coefficient of linear regression of CGMS on FSBG] were calculated. Nursing staff and patients were surveyed regarding use of the CGMS in the ICU. Results: Twenty-nine participants had 320 FSBG and corresponding CGMS readings. Sixty-two percent of participants were admitted with diabetic ketoacidosis (DKA). Two hundred and thirteen (66.6%) were accurate within the ISO standard, whereas only 70 out of 320 (21.9%) were within the 5% ADA standard. The CGMS was most accurate in euglycemia. Technical difficulties, such as adequate time for “wetting” and calibration of electrodes, arose with the sensors. The MAD was 28.3 mg/dl, the MRAD was 17.4%, and the linear regression coefficient of CGMS on FSBG was 0.834 ( p < 0.001). Conclusions: The CGMS is well tolerated by ICU patients but, at present, is not sufficiently accurate to be used for therapeutic decisions in the acute setting, particularly in patients with diabetic ketoacidosis. There is a need to find resolution to the technical issues regarding electrode “wetting” and calibration if CGMS use in the ICU setting is to provide an effective means of diabetes care and management.
Practical Considerations in the Use of Real-Time Continuous Glucose Monitoring Alerts
Authors: Mastrototaro John , Welsh John B. , Lee Scott 
Published: January 2014

Background: The safety and efficacy of real-time (RT) continuous glucose monitoring (CGM) systems in the management of type 1 diabetes are increasingly apparent. Clinical trials have demonstrated the utility of these systems in lowering hemoglobin A1c, minimizing hypoglycemia, and reducing glycemic variability. These RT systems allow patients to conveniently monitor their glucose levels by displaying concentration and trending information. Several of these RT systems provide preset alerts that sound when absolute glucose thresholds are reached. Additionally, some systems allow for predictive algorithm-based alerts that incorporate rates of change. However, clinical trials have identified significant noncompliance in the use of these devices, most notably in the pediatric and adolescent populations. A retrospective review of CGM reports shows that many patients set high and low alert thresholds at levels that result in frequent alerts, potentially resulting in patient nuisance, dismissal of consequential alerts, and eventual product abandonment. Therefore, setting the alert thresholds at appropriate high and low settings can determine the balance between either a perceived benefit by the patient and their long-term use of CGM systems or annoyance to the patient and discontinuation. Conclusion: Care should be taken to set CGM alerts at levels that result in a manageable number of notifications per day. In some cases, providers should consider not using alerts at all or consider using broad targets when initiating CGM to maximize alert specificity. Real-time CGM is safe and generally well tolerated; however, individualization of alert settings is necessary maximize the system's benefits and patient adherence.
Digital Planimetry Results in More Accurate Wound Measurements: A Comparison to Standard Ruler Measurements
Authors: Rogers Lee C. , Bevilacqua Nicholas J. , Armstrong David G. , Andros George 
Published: January 2014

Background: Cutaneous wound measurements are important to track the healing of a wound and direct appropriate therapy. The most commonly used method to calculate wound area is an estimation by multiplying the longest length by the widest width. Other devices can provide an accurate and precise measurement of the true area (TA). This study aim was to compare wound areas calculated by computerized planimetry with standard area estimation by multiplying the longest length by the widest width ( l × w). Methods: We reviewed the wound records of 10 patients with circular or oval wounds and estimated the area with the l × w method. We compared this with the TA obtained by a specialized planimetric camera. Results: Average wound size was 4.3 cm2 by l × w estimation and 3 cm2 by TA calculation. We found the l × w method overestimated wound area an average of 41%. Conclusions: Standard, manual ( l × w) measurement of cutaneous wounds inaccurately overestimates wound area by roughly 40%.
Toward an Injectable Continuous Osmotic Glucose Sensor
Authors: Johannessen Erik , Krushinitskaya Olga , Sokolov Andrey , Häfliger Philipp , Hoogerwerf Arno , Hinderling Christian , Kautio Kari , Lenkkeri Jaakko , Strömmer Esko , Kondratyev Vasily , Tønnessen Tor Inge , Mollnes Tom Eirik , Jakobsen Henrik , Zimmer Even , Akselsen Bengt 
Published: January 2014

Background: The growing pandemic of diabetes mellitus places a stringent social and economic burden on the society. A tight glycemic control circumvents the detrimental effects, but the prerogative is the development of new more effective tools capable of longterm tracking of blood glucose (BG) in vivo. Such discontinuous sensor technologies will benefit from an unprecedented marked potential as well as reducing the current life expectancy gap of eight years as part of a therapeutic regime. Method: A sensor technology based on osmotic pressure incorporates a reversible competitive affinity assay performing glucose-specific recognition. An absolute change in particles generates a pressure that is proportional to the glucose concentration. An integrated pressure transducer and components developed from the silicon micro- and nanofabrication industry translate this pressure into BG data. Results: An in vitro model based on a 3.6 × 8.7 mm large pill-shaped implant is equipped with a nanoporous membrane holding 4–6 nm large pores. The affinity assay offers a dynamic range of 36–720 mg/dl with a resolution of ±16 mg/dl. An integrated 1 × 1 mm2 large control chip samples the sensor signals for data processing and transmission back to the reader at a total power consumption of 76 μW. Conclusions: Current studies have demonstrated the design, layout, and performance of a prototype osmotic sensor in vitro using an affinity assay solution for up to four weeks. The small physical size conforms to an injectable device, forming the basis of a conceptual monitor that offers a tight glycemic control of BG.
Proficiency Testing of Human Leukocyte Antigen-DR and Human Leukocyte Antigen-DQ Genetic Risk Assessment for Type 1 Diabetes Using Dried Blood Spots
Authors: Dantonio Paul , Meredith-Molloy Nancy , Hagopian William A. , She Jin Xiong , Akolkar Beena , Cordovado Suzanne K. , Hendrix Miyono , Henderson L. Omar , Hannon W. Harry , Vogt Robert F. 
Published: January 2014

Background: The plurality of genetic risk for developing type 1 diabetes mellitus (T1DM) lies within the genes that code for the human leukocyte antigens (HLAs). Many T1DM studies use HLA genetic risk assessment to identify higher risk individuals, and they often conduct these tests on dried blood spots (DBSs) like those used for newborn bloodspot screening. One such study is The Environmental Determinants of Diabetes in the Young (TEDDY), a long-term prospective study of environmental risk factors. To provide quality assurance for T1DM studies that employ HLA genetic risk assessment, the Centers for Disease Control and Prevention (CDC) conducts both a voluntary quarterly Proficiency testing (VQPT) program available to any laboratory and a mandatory annual Proficiency testing (PT) challenge for TEDDY laboratories. Methods: Whole blood and DBS samples with a wide range of validated HLA-DR and HLA-DQ genotypes were sent to the participating laboratories. Results were evaluated on the basis of both the reported haplotypes and the HLA genetic risk assessment. Results: Of the reported results from 24 panels sent out over six years in the VQPT, 94.7% (857/905) were correctly identified with respect to the relevant HLA-DR or HLA-DQ alleles, and 96.4% (241/250) were correctly categorized for risk assessment significant improvement was seen over the duration of this program, usually reaching 100% correct categorization during the last three years. Of 1154 reported results in four TEDDY PT challenges, 1153 (99.9%) were correctly identified for TEDDY eligibility. Conclusions: The different analytical methods used by T1DM research centers all provided accurate (>99%) results for genetic risk assessment. The two CDC PT programs documented the validity of the various approaches to screening and contributed to overall quality assurance.
Influence of Oral Antidiabetic Drugs on Hyperglycemic Response to Foods in Persons with Type 2 Diabetes Mellitus as Assessed by Continuous Glucose Monitoring System: A Pilot Study
Authors: Peterson Karolina , Chlup Rudolf , Zapletalova Jana , Kohnert Klaus Dieter , Kudlova Pavla , Bartek Josef , Nakladalova Marie , Doubravova Blanka , Seckar Pavel 
Published: January 2014

Background: The purpose of this prospective open-label trial was (1) to assess the Influence of oral antidiabetic drugs (OAD) on the glycemic index (GI), glucose response curves (GRCs), daily mean plasma glucose (MPG) and (2) to compare the GI of foods in persons with OAD-treated type 2 diabetes mellitus (T2DM) with the respective GI in healthy persons (HP). Methods: Tested foods containing 50 g of carbohydrates were eaten for breakfast and dinner after 10 and 4 h of fasting, respectively. Glycemic index, GRC, and MPG were obtained using the CGMS® System Gold™ (CGMS). In T2DM patients [n = 16; age (mean ± standard error) 56.0 ± 2.25 years], foods were tested four times: tests 1, 2, and 3 were performed within one week in which placebo was introduced on day 2, and test 4 was carried out five weeks after reintroduction of OAD. Glycemic indexes, GRC, and MPG from tests 1, 2, 3, and 4 were compared. In a control group of 20 HP (age 24.4 ± 0.71 years), the mean GIs were calculated as the mean from 20 subject-related GIs. Results: In T2DM patients, subject-related assessment of GIs, GRC, and MPG distinguished persons with and without OAD effect. Nevertheless, the group-related GIs and the MPG on days 2, 8, and 39 showed no significant difference. There was no significant difference between the GIs in OAD-treated T2DM patients (test 4) versus HP (except in apple baby food). Glucose response curves were significantly larger in T2DM patients (test 4) versus HP. Conclusions: Determination of GRC and subject-related GI using the CGMS appears to be a potential means for the evaluation of efficacy of OAD treatment. Further studies are underway.
Computer-Aided Learning in Insulin Pump Training
Authors: Sirotinin Sergey V. , George Charles J. 
Published: January 2014

This technical report concerns a novel, computer-aided learning tool for patients with diabetes. The goal of the tool is to make training in the use of an insulin pump “painless,” practical, effective, and educationally rewarding. This learning tool (or application) is unique because it uses a virtual pump to facilitate learning and allow the patient to practice pump operation presents training tasks in a standardized format, and provides corrective feedback to help patients better understand and manage their diabetes. The application's acceptability was surveyed by 126 health care professionals who are experienced in diabetes education and certified in pump training. Results suggest that use of Insulet's OmniPod® Interactive Training is associated with increased training efficiency and promotes a positive attitude toward insulin pump therapy.
Impact of Tissue Heterogeneity on Noninvasive Near-Infrared Glucose Measurements in Interstitial Fluid of Rat Skin
Authors: Alexeeva Natalia V. , Arnold Mark A. 
Published: January 2014

Background: Movement of the optical interface used to collect noninvasive near-infrared spectra is known to dramatically increase prediction errors for glucose concentration measurements within the interstitial fluid of living rat skin. Prediction errors increase by more than 2.5-fold when the interface is moved before each noninvasive measurement compared to measurements where the interface position is constant throughout. Chemical heterogeneity of the skin matrix is examined as a possible mechanism for the strong sensitivity to the interface placement during noninvasive measurements conducted from transmission near-infrared absorption spectroscopy. Method: Microspectroscopy was performed over a region of the near-infrared spectrum (4000–5000 cm1) to map the concentrations of water, collagen protein, fat, and keratin protein within the skin tissue matrix through which noninvasive spectra are collected. Maps were created for multiple samples of skin excised from male and female animals. Sets of near-infrared spectra were constructed to simulate noninvasive spectra in accord with the basic tissue composition found from the microspectroscopic maps with added information corresponding to a span of glucose concentrations ranging from 5 to 35 mM and Gaussian-distributed noise. Results: Microspectroscopic maps of rat skin reveal similar patterns of heterogeneity for major chemical components of skin samples excised from both male and female animals. These maps demonstrate concentration domains with dimensions similar to the size of the fiber interface used to collect noninvasive spectra. Partial least squares calibration models generated from sets of simulated spectra demonstrate increases in prediction errors for glucose when the spectral matrix is changed in accord with the degree of chemical heterogeneity displayed in the skin maps. Prediction errors typically increase between 100 and 1000% when comparing errors generated from spectra that represent a single tissue composition versus spectra that represent a varied skin composition in accord with the distribution displayed in the skin maps. Conclusions: The distribution of the major components of skin is not uniform, but establishes domains within the skin matrix that strongly impact prediction errors for the noninvasive spectroscopic measurement of glucose within the interstitial fluid of rat dermis tissue. The observed increase in prediction error (>2.5-fold) determined from actual noninvasive measurements is within the lower range of prediction error increases demonstrated by this simulation study. These findings implicate that chemical heterogeneity within the tissue matrix is a major factor in the sensitivity of the location of the fiber interface used to collect noninvasive spectral data.
Use of Subcutaneous Interstitial Fluid Glucose to Estimate Blood Glucose: Revisiting Delay and Sensor Offset
Authors: Rebrin Kerstin , Sheppard Norman F. , Steil Garry M. 
Published: January 2014

Background: Estimates for delays in the interstitial fluid (ISF) glucose response to changes in blood glucose (BG) differ substantially among research groups. We review these findings along with arguments that continuous glucose monitoring (CGM) devices used to measure ISF delay contribute to the variability. We consider the impact of the ISF delay and review approaches to correct for it, including strategies pursued by the manufacturers of these devices. The focus on how the manufacturers have approached the problem is motivated by the observation that clinicians and researchers are often unaware of how the existing CGM devices process the ISF glucose signal. Methods: Numerous models and simulations were used to illustrate problems related to measurement and correction of ISF glucose delay. Results: We find that (1) there is no evidence that the true physiologic ISF glucose delay is longer than 5–10 min and that the values longer than this can be explained by delays in CGM filtering routines; (2) the primary impact of the true ISF delay is on sensor calibration algorithms, making it difficult to estimate calibration factors and offset (OS) currents; (3) inaccurate estimates of the sensor OS current result in overestimation of sensor glucose at low values, making it difficult to detect hypoglycemia; (4) many device companies introduce nonlinear components into their filters, which can be expected to confound attempts by investigators to reconstruct BG using linear deconvolution; and (5) algorithms advocated by academic groups are seldom compared to algorithms pursued by industry, making it difficult to ascertain their value. Conclusions: The absence of any direct comparisons between existing and new algorithms for correcting ISF delay and sensor OS current is, in part, due to the difficulty in extracting relevant details from industry patents and/or extracting unfiltered sensor signals from industry products. The model simulation environment, where all aspects of the signal can be derived, may be more appropriate for developing new filtering and calibration strategies. Nevertheless, clinicians, academic researchers, and the industry would benefit from collaborating when evaluating those strategies.
Diabetes in the Desert: What Do Patients Know about the Heat?
Authors: Nassar Adrienne A. , Childs Raymond D. , Boyle Mary E. , Jameson Kimberly A. , Fowke Margaret , Waters Ken R. , Hovan Michael J. , Cook Curtiss B. 
Published: January 2014

Background: This study aims to identify self-management strategies used by patients with diabetes in hot weather, examine knowledge of safe temperatures and exposure times, and evaluate comprehension of weather data. Methods: Patients attending an endocrinology clinic in southwestern United States were surveyed. Results: One hundred fifty-two surveys completed from November 30 to December 31, 2009 were analyzed. Mean patient age was 64 years; diabetes duration, 15 years; 51% were women, 83% had type 2 diabetes, 58% were non Hispanic white, and 77% were on insulin injections. Mean hemoglobin A1c was 7.9%; 38% had hemoglobin A1c values of 8.0% or higher. Patients used an array of personal protective measures during hot weather, and 71% limited heat exposure to less than one hour. Respondents typically took steps to protect their diabetes medication and supplies, but 37% chose to leave medications and supplies at home. Although 73% of respondents had received information regarding the effect of heat on insulin, only 39% had received information about the effect of heat on oral medications, 41% on glucose meters, and 38% on glucose test strips. The temperature at which patients took protective measures varied. Only 55% knew the definition of the heat index. Conclusion: Most survey participants took measures to protect themselves from the heat, although gaps in knowledge were evident. Many patients had suboptimal glycemic control, placing them potentially at risk for dehydration during the hottest months. Increased public awareness of this topic is needed, and diabetes education programs should include information about the heat where appropriate.
Evaluating the Clinical Accuracy of GlucoMen®Day: A Novel Microdialysis-Based Continuous Glucose Monitor
Authors: Valgimigli Francesco , Lucarelli Fausto , Scuffi Cosimo , Morandi Sara , Sposato Iolanda 
Published: January 2014

Background: The objective of this work was to determine the clinical accuracy of GlucoMen®Day, a new microdialysis-based continuous glucose monitoring system (CGMS) from A. Menarini Diagnostics (Florence, Italy). Accuracy evaluation was performed using continuous glucose-error grid analysis (CG-EGA), as recommended by the Performance Metrics for Continuous Interstitial Glucose Monitoring; Approved Guideline (POCT05-A). Methods: Two independent clinical trials were carried out on patients with types 1 and 2 diabetes mellitus, the glycemic levels of whom were monitored in an in-home setting for 100-hour periods. A new multiparametric algorithm was developed and used to compensate in real-time the GlucoMen®Day signal. The time lag between continuous glucose monitoring (CGM) and reference data was first estimated using the Poincaré plot method. The entire set of CGM/reference data pairs was then evaluated following the CG-EGA criteria, which allowed an estimation of the combined point and rate accuracy stratified by glycemic ranges. Results: With an estimated time lag of 11 minutes, the linear regression analysis of the CGM/reference glucose values yielded r = 0.92. The mean absolute error (MAE) was 11.4 mg/dl. The calculated mean absolute rate deviation (MARD) was 0.63 mg/dl/min. The data points falling within the A+B zones of CG-EGA were 100% in hypoglycemia, 95.7% in euglycemia, and 95.2% in hyperglycemia. Conclusions: The GlucoMen®Day system provided reliable, real-time measurement of subcutaneous glucose levels in patients with diabetes for up to 100 hours. The device showed the ability to follow rapid glycemic excursions and detect severe hypoglycemic events accurately. Its accuracy parameters fitted the criteria of the state-of-the-art consensus guideline for CGMS, with highly consistent results from two independent studies.
Validation of a Deconvolution Procedure (AutoDecon) for Identification and Characterization of Fasting Insulin Secretory Bursts
Authors: Johnson Michael L. , Veldhuis Paula P. , Grimmichova Tereza , Farhy Leon S. , Evans William S. 
Published: January 2014

Background: Insulin secretion is pulsatile, and has been shown to be altered in both physiologic and pathophysiologic conditions. The identification and characterization of such pulses have been challenging, partially because of the low concentrations of insulin during fasting and its short half-life. Existing pulse detection algorithms used to identify insulin pulses either cannot separate hormone pulses into their secretory burst and clearance components, or have been limited by both the subjective nature of initial peak selection and a lack of statistical verification of bursts. Methods: To address these concerns, we have developed AutoDecon, a novel deconvolution computer program. Results: AutoDecon was applied to synthetic insulin concentration-time series modeled on data derived from normal fasting subjects and simulated to reflect several sampling frequencies, sampling durations, and assay replicates. The operating characteristics of AutoDecon were compared to those obtained with Cluster, a standard pulse detection algorithm. AutoDecon performed considerably better than Cluster with regard to sensitivity and secretory burst detection rates for true positives, false positives, and false negatives. As expected, given the short half-life of insulin, sampling at 30-second intervals is required for optimal analytical results. The choice of sampling duration is more flexible and relates to the number of replicates assayed. Conclusion: AutoDecon represents a viable alternative to standard pulse detection algorithms for the appraisal of fasting insulin pulsatility.