Curtiss B. Cook

Inpatient glucose control: a glycemic survey of 126 U.S. hospitals

BACKGROUND Despite increased awareness of the value of treating inpatient hyperglycemia, little is known about glucose control in U.S. hospitals. METHODS The Remote Automated Laboratory System-Plus (RALS-Plus Medical Automation Systems, Charlottesville, VA) was used to extract inpatient point-of-care bedside glucose (POC-BG) tests from 126 hospitals for the period January to December 2007. Patient-day-weighted mean POC-BG and hypoglycemia/hyperglycemia rates were calculated for intensive care unit (ICU) and non-ICU areas. The relationship of POC-BG levels with hospital characteristics was determined. RESULTS A total of 12,559,305 POC-BG measurements were analyzed: 2,935,167 from the ICU and 9,624,138 from the non-ICU. Patient-day-weighted mean POC-BG was 165 mg/dL for ICU and 166 mg/dL for non-ICU. Hospital hyperglycemia (>180 mg/dL) prevalence was 46.0% for ICU and 31.7% for non-ICU. Hospital hypoglycemia (<70 mg/dL) prevalence was low at 10.1% for ICU and 3.5% for non-ICU. For ICU and non-ICU there was a significant relationship between number of beds and patient-day-weighted mean POC-BG levels, with larger hospitals (> or = 400 beds) having lower patient-day weighted mean POC-BG per patient day than smaller hospitals (<200 beds, P < 0.001). Rural hospitals had higher POC-BG levels compared to urban and academic hospitals (P < 0.05), and hospitals in the West had the lowest values. CONCLUSIONS POC-BG data captured through automated data management software can support hospital efforts to monitor the status of inpatient glycemic control. From these data, hospital hyperglycemia is common, hypoglycemia prevalence is low, and POC-BG levels vary by hospital characteristics. Increased hospital participation in data collection and reporting may facilitate the creation of a national benchmarking process for the development of best practices and improved inpatient hyperglycemia management.

Relationship between Inpatient Hyperglycemia and Insulin Treatment after Kidney Transplantation and Future New Onset Diabetes Mellitus

BACKGROUND AND OBJECTIVES Approximately two-thirds of kidney transplant recipients with no previous history of diabetes experience inpatient hyperglycemia immediately after kidney transplant surgery; whether inpatient hyperglycemia predicts future new onset diabetes after transplant (NODAT) is not established. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS A retrospective study was conducted to determine the risk conferred by inpatient hyperglycemia on development of NODAT within 1 year posttransplant. All adult nondiabetic kidney transplant recipients between June 1999 and January 2008 were included. Posttransplant inpatient hyperglycemia was defined as any bedside capillary blood glucose > or = 200 mg/dl or insulin therapy during hospitalization. NODAT was defined as HbA1C > or = 6.5%, fasting venous serum glucose > or = 126 mg/dl, or prescribed diet or medical therapy for diabetes mellitus. RESULTS The study cohort included 377 patients. NODAT developed in 1 (4%) of the 28 patients without inpatient hyperglycemia, 4 (18%) of the 22 patients with inpatient hyperglycemia but not treated with insulin, and in 98 (30%) of the 327 of the patients who were diagnosed with inpatient hyperglycemia and were treated with insulin. In adjusted analyses, requirement of insulin therapy during hospitalization posttransplant was associated with a 4-fold increase in NODAT (relative risk 4.01; confidence interval, 1.49 to 10.7; P = 0.006). CONCLUSION Development of inpatient hyperglycemia after kidney transplantation in nondiabetic patients significantly increased the risk of NODAT. Additionally, we observed a significantly increased risk of cardiovascular events in patients who developed NODAT.

Hyperglycemia during the Immediate Period after Kidney Transplantation

BACKGROUND AND OBJECTIVES Hyperglycemia and new-onset diabetes occurs frequently after kidney transplantation. The stress of surgery and exposure to immunosuppression medications have metabolic effects and can cause or worsen preexisting hyperglycemia. To our knowledge, hyperglycemia in the immediate posttransplantation period has not been studied. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We conducted a retrospective, observational study to characterize the prevalence and assess the pharmacologic management of hyperglycemia in kidney transplant recipients who underwent transplantation at our center between June 1999 and December 2006. Data were abstracted from electronic and pharmacy databases. RESULTS The study cohort included 424 patients (mean age 51 yr; 58% men; 25% with pretransplantation diabetes). All patients with and 87% without pretransplantation diabetes had evidence of hyperglycemia (bedside glucose >or=200 mg/dl or physician-instituted insulin therapy), whereas the prevalence of hypoglycemia was low (4.5%). Hyperglycemia was sustained throughout hospitalization. All patients with and 66% without pretransplantation diabetes required insulin at hospital discharge. Patients with pretransplantation diabetes were treated primarily with short-acting insulin during the first 24 h after transplantation but were transitioned to long-acting insulin as the hospital stay progressed. CONCLUSIONS Investigators have historically attempted to identify hyperglycemia after hospital discharge. Our data indicate that a substantial number of patients without pretransplantation diabetes develop hyperglycemia and require insulin during the hospital phase of their care immediately after kidney transplantation. Prospective studies are needed to delineate factors that contribute to development of new-onset diabetes after transplantation among patients with transient hyperglycemia.

Guidelines for Application of Continuous Subcutaneous Insulin Infusion (Insulin Pump) Therapy in the Perioperative Period

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.

Development of computer-based training to enhance resident physician management of inpatient diabetes.

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.

Transitioning Insulin Pump Therapy from the Outpatient to the Inpatient Setting: A Review of 6 Years' Experience with 253 Cases

Background: We reviewed the care of a large cohort of patients with diabetes mellitus on insulin pump therapy who required an inpatient stay. Methods: Records were reviewed of patients hospitalized between January 1, 2006, and December 31, 2011. Results: A total of 136 patients using insulin pumps had 253 hospitalizations. Mean (standard deviation) patient age was 55 (16) years, diabetes duration was 29 (15) years, and pump duration was 6 (5) years. Insulin pump therapy was continued in 164 (65%) hospitalizations. Adherence to core process measures improved over time: by 2011, 100% of cases had an endocrinology consultation, 100% had the required insulin pump order set completed, and 94% had documentation of the signed agreement specifying patient responsibilities for continued use of the technology while hospitalized. Documentation of the insulin pump flow sheet also increased but could still be located in only 64% of cases by the end of 2011. Mean glucose was not significantly different among patients who remained on insulin pump therapy compared to those for whom it was discontinued (p > .1), but episodes of severe hyperglycemia (>300 mg/dl) and hypoglycemia (<40 mg/dl) were significantly less common among pump users. No pump site infections, mechanical pump failures, or episodes of diabetic ketoacidosis were observed among patients remaining on therapy. Conclusions: With appropriate patient selection and usage guidelines, most patients using insulin pumps can safely have their therapy transitioned to the inpatient setting. Further study is needed to determine whether this approach can be translated to other hospital settings.

Use of Continuous Subcutaneous Insulin Infusion (Insulin Pump) Therapy in the Hospital: A Review of One Institution's Experience

Background: This article reviews the performance of our hospitals 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.

A disposable tear glucose biosensor - Part 1: Design and concept testing

Background: Tear glucose has been suggested previously as a potential approach for the noninvasive estimation of blood glucose. While the topic remains unresolved, an overview of previous studies suggests the importance of a tear sampling approach and warrants new technology development. A concept device is presented that meets the needs of a tear glucose biosensor. Methods: Three approaches to chronoamperometric glucose sensing were evaluated, including glucose oxidase mediated by potassium ferricyanide or oxygen with a hydrogen peroxide catalyst, Prussian blue, and potassium ferricyanide-mediated glucose dehydrogenase. For tear sampling, calcium alginate, poly(2-hydroxyethyl methacrylate), and polyurethane foam were screened as an absorbent tear sampling material. A quantitative model based on the proposed function of concept device was created. Results: For glucose sensing, it was found that potassium ferricyanide with glucose dehydrogenase was ideal, featuring oxygen insensitivity, long-term stability, and a lower limit of detection of 2 μM glucose. Polyurethane foam possessed all of the required characteristics for tear sampling, including reproducible sampling from a hydrogel-simulated, eye surface (4.2 ± 0.5 μl; n = 8). It is estimated that 100 μM of glucose tear fluid would yield 135 nA (14.9% relative standard deviation). Conclusion: A novel concept device for tear glucose sampling was presented, and the key functions of this device were tested and used to model the performance of the final device. Based on these promising initial results, the device is achievable and within reach of current technical capabilities, setting the stage for prototype development.

Outpatient-to-Inpatient Transition of Insulin Pump Therapy: Successes and Continuing Challenges

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.

Development of a novel single sensor multiplexed marker assay

There is an increasing desire to measure multiple analytes simultaneously for disease management and detection. However, in the case of invasive devices, it would be better to obtain one small sample and immediately be able to detect the analytes rapidly, as in the case of self-monitoring blood glucose, without the need for additional steps, arrays, or reagents. Electrochemical impedance spectroscopy is used to measure the interaction between ultralow levels of analyte and molecular recognition element in a label-free and rapid manner. Gold nanoparticles were attached to antibodies against interleukin-12 and tumor necrosis factor-α, typical inflammatory markers found with near overlapping responses, on an impedance spectroscopy based biosensor. Cross-reactivity and specificity of tuned antibodies were verified using ELISA. Impedance frequency was quantified by concentration gradients of marker against the device. The natural impedance frequency for interleukin-12 (5.00 Hz) was tuned to a lower frequency four Hertz away from one another for better signal processing. This was accomplished without significantly altering the lower limits of detection (<4 pg ml(-1) and ∼60 pg ml(-1) for interleukin-12 and tumor necrosis factor-α, respectively), no cross-reactivity and specificity as determined by ELISAs. With modeling the nanoscale effects and further development, a larger tuning will be possible for making a better multiplexed sensor. Although interleukin-12 and TNF-α equivalent circuit calculations were modeled here, a sensor with the potential to measure multiple markers at once might offer a solution on the sensor front for simplified management of conditions such as diabetes, where both glucose and hemoglobin A1c values could be obtained.