Citations

Despite the emergence of glucometrics (i.e., systematic analysis of data on blood glucose levels of inpatients) as a subject of high interest, there remains a lack of standardization on how glucose parameters are measured and reported. This dilemma must be resolved before a national benchmarking process can be developed that will allow institutions to track and compare inpatient glucose control performance against established guidelines and that can also be supported by quality care organizations. In this article, we review some of the questions that need to be resolved through consensus and review of the evidence, and discuss some of the limitations in analyzing and reporting inpatient glucose data that must be addressed (or at least accepted as limitations) before hospitals can commit resources to gathering, compiling, and presenting inpatient glucose statistics as a health care quality measure. Standards must include consensus on which measures to report, the unit of analysis, definitions of targets for hyperglycemia treatment, a definition of hypoglycemia, determination of how data should be gathered (from chart review or from laboratory information systems), and which type of sample (blood or point of care) should be used for analysis of glycemic control. Hospitals and/or their representatives should be included in the discussion. For inpatient glucose control to remain a focus of interest, further dialogue and consensus on the topic are needed.

Case reports indicate that diabetes patients receiving outpatient insulin pump therapy have been allowed to continue treatment during surgical procedures. Although allowed during surgery, there is actually little information in the medical literature on how to manage patients receiving insulin pump therapy during a planned surgical procedure. A multidisciplinary work group reviewed current information regarding the use of insulin pumps in the perioperative period. Although the work group identified safety issues specific to surgical scenarios, it believed that with the use of standardized guidelines and a checklist, continuation of insulin pump therapy during the perioperative period is feasible. A sample set of protocols have been developed and are summarized. A policy outlining clear procedures should be established at the institutional level to guide physicians and other staf if the devices are to be employed during the perioperative period. Additional clinical experience with the technology in surgical scenarios is needed, and consensus should be developed for insulin pump use in the perioperative phases of care.

Background: A concept for a tear glucose sensor based on amperometric measurement of enzymatic oxidation of glucose was previously presented, using glucose dehydrogenase flavin adenine dinucleotide (GDH-FAD) as the enzyme. Glucose dehydrogenase flavin adenine dinucleotide is further characterized in this article and evaluated for suitability in glucose-sensing applications in purified tear-like saline, with specific attention to the effect of interfering substances only. These interferents are specifically saccharides that could interact with the enzymatic activity seen in the sensor's performance. Methods: Bench top amperometric glucose assays were performed using an assay solution of GDH-FAD and ferricyanide redox mediator with samples of glucose, mannose, lactose, maltose, galactose, fructose, sucrose, and xylose at varying concentrations to evaluate specificity, linear dynamic range, signal size, and signal-to-noise ratio. A comparison study was done by substituting an equivalent activity unit concentration of glucose oxidase (GOx) for GDH-FAD. Results: Glucose dehydrogenase flavin adenine dinucleotide was found to be more sensitive than GOx, producing larger oxidation currents than GOx on an identical glucose concentration gradient, and GDH-FAD exhibited larger slope response (-5.65 × 10 −7 versus −3.11 × 10 −7 A/mM), signal-to-noise ratio (18.04 versus 2.62), and linear dynamic range (0–30 versus 0–10 mM), and lower background signal (−7.12 versus −261.63 nA) than GOx under the same assay conditions. GDH-FAD responds equally to glucose and xylose but is otherwise specific for glucose. Conclusion: Glucose dehydrogenase flavin adenine dinucleotide compares favorably with GOx in many sensor-relevant attributes and may enable measurement of glucose concentrations both higher and lower than those measurable by GOx. GDH-FAD is a viable enzyme to use in the proposed amperometric tear glucose sensor system and perhaps also in detecting extreme hypoglycemia or hyperglycemia in blood.

Many reports have documented the negative health consequences that environmental stressors can have on patients with diabetes. Studies examining the interaction between the environment and a patient with diabetes can be unified under a single discipline termed “geoenvironmental diabetology.” Geoenvironmental diabetology is defined more specifically as the study of how geophysical phenomena impact a patient with diabetes, to include effects on metabolic control, ancillary equipment (e.g., glucometers and insulin pumps), medications, supplies, access to care, and influences on the adaptive strategies employed by patients to care for their diabetes under extreme circumstances. Geological events such as natural disasters (e.g., earthquakes) or extreme weather (e.g., heat waves) are examples of stressors that can affect patients with diabetes and that can be included under the heading of geoenvironmental diabetology. As proposed here, geoenvironmental diabetology refers to how events in the physical world affect those with diagnosed diabetes, rather than how environmental factors might trigger development of disease. As the global prevalence of diabetes continues to increase, including in parts of the world that are especially vulnerable to disasters and climate change, further discussion is warranted on how to best prepare for management of diabetes under conditions of extreme geological and weather events and a changing climate. An overview is presented of various studies that have detailed how geoenvironmental phenomena can adversely affect patients with diabetes and concludes with a discussion of requirements for developing strategies for geoenvironmental diabetes management.

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.

Background: Insulin pump therapy is a complex technology prone to errors when employed in the hospital setting. When patients on insulin pump therapy require hospitalization, practitioners caring for them must decide whether to allow continued pump use. We provide the largest review regarding transitioning insulin pump therapy from the outpatient to inpatient setting. Method: Records of inpatient insulin pump users were retrospectively analyzed at a metropolitan Phoenix hospital between January 2006 and December 2009. Adherence to institutional procedures on insulin pump use was assessed, glycemic control was determined, and adverse events were examined. Results: We examined records on 65 patients with insulin pumps, totaling 125 hospitalizations. Mean (standard deviation) patient age was 55 (17) years, diabetes duration was 27 (14) years, pump duration was 6 (5) years, length of hospital stay was 4.7 (6.3) days, hemoglobin A1c was 7.3 (1.3)%, 85% had type 1 diabetes mellitus, 57% were women, and 97% were white. Admissions involving insulin pumps increased (23 in 2006, 17 in 2007, 40 in 2008, and 45 in 2009). Insulin pump therapy was continued in 83 (66%) hospitalizations. Among these hospitalizations, endocrinology consultations were obtained in 89%, consent agreements were found in 83%, insulin pump order sets were completed in 89%, admission glucose was checked in 100%, and nursing assessments of pump insertion sites were documented in 89%, but bedside insulin pump flow sheets were found in only 55%. Mean glucose of 175 (57) mg/dl was not significantly different than that in hospitalizations where insulin pumps were discontinued [175 (42) mg/dl] or used intermittently [177 (7) mg/dl]. There was one instance of a pump catheter kinking; however, no other adverse events (pump site infections, mechanical pump failure, diabetic ketoacidosis) were observed, and there were no use-related fatalities. Conclusions: Most patients using insulin pumps can safely have their therapy transitioned when hospitalized. A policy on inpatient continuous subcutaneous insulin infusion use can be successfully implemented. Compliance with required procedures can be achieved, although there was room to improve adherence with some process measures. Further study is needed to determine how to optimize glycemic control when pumps are allowed during hospitalization.

Background: We presented a concept for a tear glucose sensor system in an article by Bishop and colleagues in this issue of Journal of Diabetes Science and Technology . A unique solution to collect tear fluid and measure glucose was developed. Individual components were selected, tested, and optimized, and system error modeling was performed. Further data on prototype testing are now provided. Methods: An integrated fluidics portion of the prototype was designed, cast, and tested. A sensor was created using screen-printed sensors integrated with a silicone rubber fluidics system and absorbent polyurethane foam. A simulated eye surface was prepared using fluid-saturated poly(2-hydroxyethyl methacrylate) sheets, and the disposable prototype was tested for both reproducibility at 0, 200, and 400 μ M glucose ( n = 7) and dynamic range of glucose detection from 0 to 1000 μ M glucose. Results: From the replicated runs, an established relative standard deviation of 15.8% was calculated at 200 μ M and a lower limit of detection was calculated at 43.4 μ M . A linear dynamic range was demonstrated from 0 to 1000 μ M with an R 2 of 99.56%. The previously developed model predicted a 14.9% variation. This compares to the observed variance of 15.8% measured at 200 μ M glucose. Conclusion: With the newly designed fluidics component, an integrated tear glucose prototype was assembled and tested. Testing of this integrated prototype demonstrated a satisfactory lower limit of detection for measuring glucose concentration in tears and was reproducible across a physiological sampling range. The next step in the device design process will be initial animal studies to evaluate the current prototype for factors such as eye irritation, ease of use, and correlation with blood glucose.

Background: Treating hyperglycemia promotes better outcomes among inpatients. Knowledge deficits about management of inpatient diabetes are prevalent among resident physicians, which may affect the care of a substantial number of these patients. Methods: A computer-based training (CBT) curriculum on inpatient diabetes and hyperglycemia was developed and implemented for use by resident physicians and focuses on several aspects of the management of inpatient diabetes and hyperglycemia: (1) review of importance of inpatient glucose control, (2) overview of institution-specific data, (3) triaging and initial admission actions for diabetes or hyperglycemia, (4) overview of pharmacologic management, (5) insulin-dosing calculations and ordering simulations, (6) review of existing policies and procedures, and (7) discharge planning. The curriculum was first provided as a series of lectures, then formatted and placed on the institutional intranet as a CBT program. Results: Residents began using the inpatient CBT in September 2008. By August 2009, a total of 29 residents had participated in CBT: 8 in family medicine, 12 in internal medicine, and 9 in general surgery. Most of the 29 residents confirmed that module content met stated objectives, considered the information valuable to their inpatient practices, and believed that the quality of the online modules met expectations. The majority reported that the modules took just the right amount of time to complete (typically 30 min each). Conclusions: Improvement in inpatient diabetes care requires continuous educational efforts. The CBT format and curriculum content were well accepted by the resident physicians. Ongoing assessment must determine whether resident practice patterns are influenced by such training.

Background: Hypoglycemia is often cited as a barrier to achieving inpatient glycemic targets. We sought to characterize hypoglycemic events in our institution by work-shift cycle and by specific treatment area. Methods: Capillary (bedside) and blood (laboratory) glucose values of <70 mg/dl for patients with either a known diagnosis of diabetes or with evidence of hyperglycemia were abstracted from our laboratory database for hospitalizations between October 1, 2007, and February 3, 2008. Hypoglycemic events were analyzed by 12 h nursing work-shift cycles (day shift, 07:00 to 18:59; night shift, 19:00 to 06:59) and by the six medical, surgical, and intensive care areas in the hospital (designated areas 1 to 6). Results: We identified 206 individual patients with either diabetes or hyperglycemia (mean age, 67 years; 56% men; 83% white) who had 423 hypoglycemic events. There were 78% more hypoglycemic events during the night shift ( n = 271 events in 128 individual patients) than during the day shift ( n = 152 events in 96 individual patients). Most of the night-shift hypoglycemic measurements were detected between 04:00 and 04:59 or 06:00 and 06:59. The mean hypoglycemic level was comparable between shifts ( p = .79) and across the six inpatient areas. The number of hypoglycemic events per person increased with lengths of hospital stay >5 days. The prevalence of hypoglycemia varied across patient care areas within the hospital, with most (28%) detected in one area of the hospital. Conclusion: There are temporal and geographic patterns in the occurrence of hypoglycemia among patients with diabetes or hyperglycemia in our hospital. Further study should focus on the reasons underlying these variations so that specific interventions can address the risk of hypoglycemia during peak times and places.

Background: This article reviews the performance of our hospital's inpatient insulin pump policy. Methods: Twenty-five hospital admissions of 21 unique patients receiving outpatient insulin pump therapy were reviewed. Results: Between November 1, 2005, and November 30, 2006, there were 25 hospital admissions involving 21 patients receiving outpatient insulin pump therapy. The average age and duration of diabetes among these 21 patients was 50 and 29 years, respectively; 67% were women, 90% had type 1 diabetes, and all were white. The mean length of hospital stay was 4 days, and the average reported length of insulin pump therapy was 4 years. Patients in 16 of the admissions were identified as candidates for continued use of the insulin pump during the hospital stay. Over 90% of patients remaining on the insulin pump had documentation by nursing of the presence of the pump at the time of admission; 100% of the patients had an admission glucose recorded; 88% had a record of signed patient consent; 81% had evidence of completed preprinted insulin pump orders; 75% received a required endocrine consultation; and 75% of cases had documentation of completed bedside flow sheet. A high frequency of both hypoglycemic and hyperglycemic events occurred in the patients; however, no adverse events were related directly to the insulin pump. Conclusions: Insulin pump therapy can be safely continued in the hospital setting. While staff compliance with required procedures was high, there was still room for improvement. More data are needed, however, on whether this method of insulin delivery is effective for controlling hyperglycemia in hospitalized patients.