Effect of diabetes mellitus on outcomes of hyperglycemia in a mixed medical surgical intensive care unit

Background:

Intensive insulin therapy and degree of glycemic control in critically ill patients remains controversial, particularly in patients with diabetes mellitus. We hypothesized that diabetic patients who achieved tight glucose control with continuous insulin therapy would have less morbidity and lower mortality than diabetic patients with uncontrolled blood glucose.

Method:

A retrospective chart review was performed on 395 intensive care unit (ICU) patients that included 235 diabetic patients. All patients received an intravenous insulin protocol targeted to a blood glucose (BG) level of 80–140mg/dl. Outcomes were compared between (a) nondiabetic and diabetic patients, (b) diabetic patients with controlled BG levels (80–140mg/dl) versus uncontrolled levels (>140 mg/dl), and (c) diabetic survivors and nonsurvivors.

Results:

Diabetic patients had a shorter ICU stay compared to nondiabetic patients (10 ± 0.7 vs 13 ± 1.1, p = .01). The mean BG of the diabetic patients was 25% higher on average in the uncontrolled group than in the controlled (166 ± 26 vs 130 ± 9.4 mg/dl, p < .01). There was no difference in ICU and hospital length of stay (LOS) between diabetic patients who were well controlled compared to those who were uncontrolled. Diabetic nonsurvivors had a significantly higher incidence of hypoglycemia (BG <60 mg/dl) compared to diabetic survivors.

Conclusion:

The results showed that a diagnosis of diabetes was not an independent predictor of mortality, and that diabetic patients who were uncontrolled did not have worse outcomes. Diabetic nonsurvivors were associated with a greater amount of hypoglycemic episodes, suggesting these patients may benefit from a more lenient blood glucose protocol.     

Reduction of postprandial glycemic excursions in patients with type 1 diabetes: a novel human insulin formulation versus a rapid-acting insulin analog and regular human insulin

Background:

Evaluation of postprandial glycemic excursions in patients with type 1 diabetes with three prandial insulins: VIAject™ (Linjeta™), an ultra-fast insulin (UFI); insulin lispro (LIS); and regular human insulin (RHI).

Methods:

After stabilization of preprandial glycemia, 18 patients received a subcutaneous injection with an individualized insulin dose prior to a meal.

Results:

Injection of UFI resulted in a more rapid insulin absorption than with either LIS or RHI (time to half-maximal insulin levels: 13.1 ± 5.2 vs 25.4 ± 7.6 and 38.4 ± 19.5 min; p = .001 vs LIS and p < .001 vs RHI, LIS vs. RHI p < .001). Maximal postprandial glycemia was lower with UFI (0–180 min; 157 ± 30 mg/dl; p = .002 vs RHI) and LIS (170 ± 42 mg/dl; p = .668 vs RHI) than after RHI (191 ± 46 mg/dl; RHI vs LIS p = .008). The difference between maximum and minimum glycemia was smaller with UFI (70 ± 17 mg/dl) than with either RHI (91 ± 33 mg/dl; p = .007 vs UFI) or LIS (89 ± 18 mg/dl; p = .011 vs UFI). Also, the area under the blood glucose profile was lower with UFI than with RHI (0–180 min; 21.8 ± 5.8 vs 28.4 ± 7.6 g·min/dl; p < .001).

Conclusions:

The rapid absorption of UFI results in a reduction of postprandial glycemic excursions.     

Hemoglobin A1c testing in an emergency department

Background

Emergency department (ED) visits for hyperglycemia are common and costly. Enhanced strategies for recognizing and managing patients with diabetes in the ED are needed. Hemoglobin A1c (A1C) testing is typically used to assess level of glycemic control in the 2–3 months preceding an office visit. In this article, we report on potential roles for point-of-care (POC) A1C testing in the ED for patients presenting with uncontrolled hyperglycemia.

Methods

We enrolled patients presenting to an urban tertiary care hospital ED with blood glucose (BG) ≥200 mg/dl who were otherwise stable for discharge (n = 86) in a prospective, nonrandomized pilot study. Antihyperglycemic medication management, survival-skills diabetes self-management education, and health system navigation were provided. Followup visits took place at 24–72 hours and at 2 and 4 weeks. Point-of-care A1C testing was performed at baseline and at 2 weeks. Baseline A1C results were used by the ED physician and the educator to inform the patient of likely preadmission glycemic classification, and the potential role that the (diabetes mellitus) DM medication regimen assigned in the ED had in enabling overall progress in glycemic control at 2 weeks post-ED initiation of treatment.

Results

At baseline, 50% of POC A1C values were >13%. Mean BG fell from 356 ± 110 mg/dl to 183 ± 103 mg/dl at 4 weeks (average decrease of 173.5 g/dl, p < 0.001). Mean A1C fell by 0.4%, from 12.0 ± 1.5% to 11.6 ± 1.6% at 2 weeks, p = 0.048. There were zero instances of day 1 hypoglycemia and overall hypoglycemia rates were low (1.3%).

Conclusions

Point-of-care A1C testing in the ED helped inform both the provider and the patient of likely prior glycemic status, including unrecognized or uncontrolled type 2 diabetes, and allowed emphasis of the importance of timely diabetes self-management education and medication management in preventing acute and chronic complications. Followup POC A1C testing at 2 weeks was used to confirm early improvement in glycemic control postintervention.     

Concealed Maternal Blood Glucose Excursions Correlate with Birth Weight Centile

Background

The objective of this study was to test the hypothesis that maternal blood glucose excursions correlate with deviation from optimized birth weight.

Methods

Patients were recruited for 3-day continuous glucose monitoring (CGM) plus self-blood glucose monitoring followed by routine diabetes screening at 26-28 weeks gestation. Patients and caregivers were blinded to CGM results. The magnitude and duration of blood glucose (BG) excursions were measured as a “glycemia index.” A customized birth weight centile was calculated.

Results

Twenty-three patients consented, 21 completed the study: 5 diabetic and 16 nondiabetic individuals. The duration of CGM was 72 (±7.2) hours, and each patient performed self-BG monitoring ≥3 times per day. All diabetic and 10 nondiabetic patients had several measured BG excursions above 130 mg/dl. A positive correlation was observed between birth weight centile and glycemia index above 130 (p < 0.03); the trend persisted for nondiabetic patients alone (p < 0.05). No significant correlation was noted between birth weight centile and average 3-day CGM values, 3-day fasting BG, average 3-day self-BG monitoring values, or diabetes screening BG value.

Conclusions

The glycemia index has a better correlation with birth weight centile than BG measured by conventional methods in a mixed diabetic and nondiabetic population. Fetal exposure to maternal blood glucose excursions correlates positively with fetal growth, even in nondiabetic patients with apparently normal glucose tolerance.     

Evaluation of Point-of-Care Blood Glucose Measurements in Patients with Diabetic Ketoacidosis or Hyperglycemic Hyperosmolar Syndrome Admitted to a Critical Care Unit

Background

Point-of-care (POC) blood glucose (BG) measurement is currently not recommended in the treatment of patients presenting with diabetic ketoacidosis (DKA) or hyperglycemic hyperosmolar syndrome (HHS).

Methods

We prospectively evaluated and compared capillary and venous POC BG values with laboratory venous glucose in patients with DKA or HHS admitted to one critical care unit over 8 months.

Results

Venous laboratory glucose was strongly correlated with venous (r = 0.98) and capillary (r = 0.96) POC glucose values, though POC glucose values were higher than venous laboratory values (venous POC 21 ± 3 mg/dl, capillary POC 30 ± 4 mg/dl; both p < .001). Increased plasma osmolality had no effect on glucose meter error, while acidemia (pH < 7.3) was associated with greater glucose meter error (p = .04) independent of glucose levels. Comparing hypothetical insulin infusion rates based on laboratory venous glucose to actual infusion rates based on POC glucose values showed that 33/61 insulin infusion rates would have been unchanged, while 28 out of 61 rates were on average 7% ± 2% higher. There were no instances of hypoglycemia in any of the patients.

Conclusions

Overall, both venous and capillary POC BG values were safe for the purpose of titrating insulin infusions in patients with severe hyperglycemia. Acidemia, but not hyperosmolality, increased POC BG value errors.     

Retrospective Outcomes of Glucose Control in Critically Ill Children

Background

Hyperglycemia is a significant problem for critically ill children. Treatment for hyperglycemia remains controversial. This study explores the effect of controlling blood glucose (BG) in hyperglycemic critically ill children.

Methods

A retrospective cohort of nondiabetic critically ill children (defined as requiring mechanical ventilation and/or vasopressors) with BG persistently ≥150 mg/dl and treated with insulin (treatment group) were compared with a historical cohort of similar children who did not receive interventions to control hyperglycemia (baseline group).

Results

There were 130 children in the treatment group and 137 children in the baseline group. Mean BG in the treatment group was 140 ± 24 mg/dl compared with 179 ± 47 mg/dl in the baseline group (p < .001). After adjusting for patient characteristics, cointerventions, and glucose metrics, patients in the treatment group had 2.5 fewer intensive care unit (ICU)-free days (i.e., number of days alive and discharged from ICU within 28 days after inclusion) than the baseline group (p = .023). Glucose control was not independently associated with duration of ICU stay, ventilator-free days, vasopressor-free days, or mortality.

Conclusions

Blood glucose control appears associated with worse outcomes in critically ill children. Our data combined with conflicting results in adults leads us to strongly advocate for the conduct of randomized trials on glucose control in critically ill children.     

Pharmacokinetics and Postprandial Glycemic Excursions following Insulin Lispro Delivered by Intradermal Microneedle or Subcutaneous Infusion

Background

Intradermal (ID) delivery has been shown to accelerate insulin pharmacokinetics (PK). We compared the PK and pharmacodynamic (PD) effects of insulin lispro administered before two daily standardized solid mixed meals (breakfast and lunch), using microneedle-based ID or traditional subcutaneous (SC) delivery.

Method

The study included 22 subjects with type 1 diabetes in an eight-arm full crossover block design. One arm established each subject’s optimal meal dose. In six additional arms, the optimal, higher, and lower doses (+30%, -30%) were each given ID and SC delivery, in random order. The final arm assessed earlier timing for the ID optimal dose (-12 versus -2 min). The PK/PD data were collected for 6 h following meals. Intravenous basal regular insulin was given throughout, and premeal blood glucose (BG) adjusted to 115 mg/dl.

Results

The primary end point, postprandial time in range (70–180 mg/dl), showed no route-based differences with a high level of overall BG control for both SC and ID delivery. Secondary insulin PK end points showed more rapid ID availability versus SC across doses and meals (∆Tmax -16 min, ∆T50rising -7 min, ∆T50falling -30 min, all p < .05). Both intrasubject and intersubject variability for ID Tmax were significantly lower. Intradermal delivery showed modest, statistically significant secondary PD differences across doses and meals, generally within 90–120 min postprandially (∆12 mg/dl BG at 90 min, ∆7 mg/dl BGmax, ∆7 mg/dl mean BG 0–2 h, all p < .05).

Conclusions

This study indicates that ID insulin delivery is superior to SC delivery in speed of systemic availability and PK consistency and may improve postprandial glucose control.     

Usage and effectiveness of the low glucose suspend feature of the Medtronic Paradigm Veo insulin pump

Background

Sensor-augmented insulin pumps may be programmed to suspend insulin delivery in response to hypoglycemia. The Medtronic Paradigm® Veo™ pump with automatic low glucose suspend (LGS) was released in 2009. Data from 7 months of real-world use of the system were analyzed to assess usage patterns and effectiveness of LGS.

Method

Data from 935 patients totaling 49,867 patient days were collected; the LGS feature was on for 82% of these days. A subset of 278 subjects who used the pump for ≥3 months was analyzed separately; these subjects provided 28,401 patient days of data, with LGS used for 92% of the time.

Results

The LGS threshold was most commonly set between 50 and 60 mg/dl. A total of 27,216 LGS events occurred, and 60% began in the afternoon or evening. The median duration of LGS events was 9.87 min, 45% lasted for <5 min, and 11% lasted for >115 min (equivalent to the full extent of the LGS event between 115 and 120 min). Among the episodes lasting for >115 min, the mean sensor glucose (SG) was 58.8 ± 12.4 mg/dl at LGS activation (time 0), rose to 102.2 ± 52.8 mg/dl by the end of the LGS episode (when insulin delivery was automatically resumed), and was 150.1 ± 68.6 mg/dl at 240 min. In the 278-subject subgroup, LGS usage significantly reduced the number of SG readings <50 mg/dl (p = 0.001) and >300 mg/dl (p = 0.001).

Conclusions

The LGS feature was on for most of the patient days in the study. Most LGS episodes lasted for <10 min. Use of the LGS feature significantly reduced exposure to hypoglycemia. Profound hyperglycemia resulting from LGS episodes lasting >115 min was not observed.     

Hematocrit compensation in electrochemical blood glucose monitoring systems

Background

Hematocrit (Hct) is a common interferent in test strips used by diabetes patients to self-monitor blood glucose (BG), resulting in measurement bias. Described is an electrochemical BG monitoring system (OneTouch^® Verio™) that uses a cofacial sensor design, soluble enzyme chemistry, and multiphasic waveform to effectively correct for patient Hct, delivering an accurate reading for whole BG.

Methods

The test strip comprises thin-film gold and palladium electrodes arranged cofacially and spatially separated with a thin spacer. Soluble glucose-sensing reagents are located on the lower palladium electrode and are hydrated on sample application. Blood glucose is oxidized by flavoprotein glucose dehydrogenase, with electron transfer via (reduced) potassium ferrocyanide mediator at the palladium electrode. Hematocrit levels are estimated by measuring oxidation of mediator diffusion to the upper gold electrode during the first portion of the assay. The Hct-corrected glucose levels are determined by an on-meter algorithm.

Results

In performance testing of blood samples at five glucose levels (30–560 mg/dl) and five Hct levels (19–61%), using 12 test meters and 3 test strip lots, 100% of results (N = 2700) met International Organization for Standardization accuracy criteria (within ± 15 mg/dl and ± 20% of reference results at glucose levels of <75 and ≥75 mg/dl, respectively). Furthermore, 99.9% (2698 of 2700) of results were within ±12 mg/dl and ± 15% of reference values at glucose levels <80 and ≥80 mg/dl, respectively.

Conclusions

The technology used in this system provides accurate BG measurements that are insensitive to Hct levels across the range 20–60%.     

Overnight versus 24 Hours of Continuous Subcutaneous Insulin Infusion as Supplement to Oral Antidiabetic Drugs in Type 2 Diabetes

Background

Basal continuous subcutaneous insulin infusion (CSII) therapy at a fixed rate may effectively improve glycemic control in patients with type 2 diabetes when oral antidiabetic treatment fails. Regimens of simple constant subcutaneous delivery of insulin may provide theoretical advantages in type 2 diabetes.

Methods

Ten subjects with type 2 diabetes who obtained insufficient glycemic control on oral antidiabetic drugs were included. Following an initial control day, two periods of 3 days with CSII of a rapid-acting insulin analogue, 1.5 IU/h (dose obtained from a preceding study), for 8 hours overnight and for 24 hours, respectively, were carried out in random order. Profiles of serum insulin aspart, serum endogenous insulin, and plasma glucose were recorded.

Results

Compared to the control day, an 8-hour overnight insulin infusion during a 3-day period improved fasting plasma glucose (FPG) (mean differences ± SEM; Δ59.0 ± 10.1 mg/dl; p < 0.01) and 2-hour postprandial plasma glucose (PPPG) (Δ57.8 ± 10.6 mg/dl; p < 0.01) after breakfast. Compared to an 8-hour overnight infusion, a 24-hour infusion further improved all three PPPG values after breakfast, lunch, and dinner (Δ28.8 ± 8.1 mg/dl, Δ30.6 ± 8.1 mg/dl, and Δ35.1 ± 7.9 mg/dl; p < 0.01). During insulin infusion, only one hypoglycemic episode with PG <55.8 mg/dl and mild symptoms was recorded.

Conclusion

Continuous subcutaneous insulin infusion with a rapid-acting insulin analogue at a fixed rate of 1.5 IU/h, either overnight or for 24 hours, improved glycemic control without safety concerns in patients with type 2 diabetes who had secondary failure to oral antidiabetic drugs. The effect on FPG was similar for both treatments, whereas the effect on PPPG was superior when insulin was infused during the entire 24 hours.     

Use of a continuous glucose sensor in an extracorporeal life support circuit

Background

Standard care for infants on extracorporeal life support (ECLS) relies on intermittent measurement of blood glucose (BG); however, this can lead to significant changes in BG that go unrecognized for several hours. The present study was designed to assess performance and clinical applicability of a subcutaneous glucose sensor technology modified for use as a blood-contacting sensor within the ECLS circuit.

Methods

Twelve children, aged 3 years or less, requiring ECLS support were studied. Three continuous glucose sensors (Medtronic MiniMed) were inserted into hubs placed in line with the ECLS circuit. Blood glucose was assessed with a laboratory analyzer (BG_LAB; Bayer Rapidlab 860) approximately every 5 h (mean 4.9 ± 3.3 h) with more frequent samples obtained with a bedside monitor (HemoCue) as needed. Sensor current (I_SIG) was transmitted to a laptop computer and retrospectively calibrated using BG_LAB. Sensor performance was assessed by mean absolute relative difference (MARD), linear regression slope and intercept, and correlation, all with BG_LAB as reference.

Results

The BG_LAB averaged 107.6 ± 36.4 mg/dl (mean ± standard deviation) ranging from 58 to 366 mg/dl. The MARD was 11.4%, with linear regression slope (0.86 ± 0.030) and intercept (9.0 ± 3.2 mg/dl) different from 1 and 0, respectively (p < .05), and correlation (r² = 0.76; p < .001). The system was not associated with any adverse events, and placement and removal into the hubs was easily accomplished. Instances in which more frequent BG values were obtained using a bedside HemoCue (BG_HEMO) monitor showed the sensor to respond rapidly to changes.

Conclusions

We conclude that continuous sensors can be adapted for use in an ECLS circuit with accuracy similar to or better than that achieved with the subcutaneous site. Continuous glucose monitoring in this population can rapidly detect changes in BG that would not otherwise be observed. Further studies will be needed to assess the benefit of continuous glucose monitoring in this population.     

Technology for Hospital Management of Diabetes: Blood Glucose Measurements in Arterial Blood of Intensive Care Unit Patients Submitted to Tight Glycemic Control: Agreement between Bedside Tests

Background

Implementing tight glycemic control (TGC) in intensive care unit (ICU) patients requires accurate blood glucose (BG) monitoring. We evaluated the performance of two commercially available bedside glucometers, Accu-Chek^® and HemoCue^®, in patients admitted to the ICU and in whom TGC was applied.

Methods

Thirty-seven adult ICU patients were prospectively included. During 48 hours, BG was determined simultaneously on the same arterial blood sample using the two point-of-care testing (POCT) glucometers as compared with the standard technique. Data of 452 paired measurements were analyzed using linear regression, Clark error grid analysis (EGA), the method of Bland–Altman, and the GLYCENSIT procedure.

Results

Both tested glucometers showed satisfactory results when evaluated with linear regression and EGA. Correlation coefficients were above 0.9, and 100% of all the glucose readings were within the safe zones A and B using EGA. However, when applying more appropriate tests, both sensors failed to provide sufficient accuracy in the setting of TGC in ICU patients. The Hemocue revealed a bias of >10 mg/dl with a trend to systematically overestimate the actual BG value. The bias for the Accu-Chek was 6 mg/dl with wide limits of agreement and a variable over- and underestimation of the actual BG value depending on the level of BG (hypo-, normo-, or hyperglycemia).

Conclusions

When TGC is implemented in ICU practice, caution is warranted when adjusting insulin rates based only on BG readings obtained by the tested glucometers. ICU practitioners should weigh the advantages and disadvantages of such devices: a greater bias but with a more predictable error and measurement behavior versus a somewhat lower bias but with an unpredictable direction of the difference.     

A 16-week open-label, multicenter pilot study assessing insulin pump therapy in patients with type 2 diabetes suboptimally controlled with multiple daily injections

Background

We assessed the efficacy, safety, and patient-reported outcomes (PROs) of insulin pump therapy in patients with type 2 diabetes mellitus (T2DM) who were suboptimally controlled with a multiple daily injection (MDI) regimen.

Methods

In this subanalysis of a 16-week multicenter study, 21 insulin-pump-naïve patients [age 57 ± 13 years, hemoglobin A1c (A1C) 8.4 ± 1.0%, body weight 98 ± 20 kg, total daily insulin dose 99 ± 65 U, mean ± standard deviation] treated at baseline with MDI therapy with or without oral antidiabetic agents discontinued all diabetes medications except metformin and initiated insulin pump therapy. Insulin was titrated to achieve the best possible glycemic control with the simplest possible dosing regimen. Outcome measures included A1C, fasting and postprandial glucose, body weight, incidence of hypoglycemia, and PROs.

Results

Glycemic control improved significantly after 16 weeks: A1C 7.3 ± 1.0% (−1.1 ± 1.2%, p < .001), fasting glucose 133 ± 33mg/dl (−32 ± 74 mg/dl, p < .005), and postprandial glucose 153 ± 35 mg/dl (−38 ± 46 mg/dl, p < .001). At week 16, the mean daily basal, bolus, and total insulin doses were 66 ± 36, 56 ± 40, and 122 ± 72 U (1.2 U/kg), respectively, and 90% of patients were treated with two or fewer daily basal rates. Body weight increased by 2.8 ± 2.6 kg (p < .001). Mild hypoglycemia was experienced by 81% of patients at least once during the course of the study with no episodes of severe hypoglycemia. There were significant improvements in PRO measures.

Conclusions

Insulin pump therapy using a relatively simple dosing regimen safely improved glucose control and PROs in patients with T2DM who were unable to achieve glycemic targets with MDI therapy. Controlled trials are needed to further assess the clinical benefits and cost-effectiveness of insulin pumps in this patient population.     

Postprandial glucose monitoring further improved glycemia, lipids, and weight in persons with type 2 diabetes mellitus who had already reached hemoglobin A1c goal

Background

Postprandial hyperglycemia contributes to poor glucose control and is associated with increased cardiovascular risk in type 2 diabetes mellitus (T2DM). The objective of the study was to determine the effect of postprandial self-monitoring of blood glucose (pp-SMBG) on glucose control, lipids, body weight, and cardiovascular events.

Method

Subjects with T2DM hemoglobin A1c (A1C) between 6.5 to 7.0% were randomized into the study group (at least two pp-SMBG a day and dietary modification based on glucose readings) and control group (dietary modification based on glucose readings but no mandatory pp-SMBG) for a 6-month, observational study. Oral antidiabetic drugs or insulin regimen was unchanged in either group if A1C remained less than 7.0% during the study. End points included A1C, lipids, body weight, and cardiovascular events.

Results

One hundred sixty-nine subjects, mean age 63 years, and body weight 88 kg were recruited. Hemoglobin A1c, weight, low-density lipoprotein (LDL), and triglycerides (TGs) were similar in the groups at baseline. By the end of 6 months, A1C (6.7 ± 0.1 to 6.4 ± 0.1%, p < .05), body weight (88.5 ± 7.3 to 85.2 ± 6.3 kg, p < .05), LDL (92.3 ± 2 8.4 to 81.1 ± 22.6 mg/dl, p < .05), and TGs (141 ± 21 to 96 ± 17 mg/dl, p < .05) decreased in the study group, but did not change in the control group. No cardiovascular events were observed in either group during the 6-month study period.

Conclusions

In T2DM subjects who had already reached their A1C goal, pp-SMBG at least twice a day was associated with further improvement in glycemia, lipids, and weight, as well as exercise and dietary habit. We assume that lifestyle modification promoted by postprandial hyperglycemia awareness may underlie these findings. These results substantiate the importance of implementing pp-SMBG into lifestyle modification, and emphasize that pp-SMBG is critical in the control of T2DM.     

Benchmarking glucose results through automation: the 2009 Remote Automated Laboratory System Report

Background

Hyperglycemia in the adult inpatient population remains a topic of intense study in U.S. hospitals. Most hospitals have established glycemic control programs but are unable to determine their impact. The 2009 Remote Automated Laboratory System (RALS) Report provides trends in glycemic control over 4 years to 576 U.S. hospitals to support their effort to manage inpatient hyperglycemia.

Methods

A proprietary software application feeds de-identified patient point-of-care blood glucose (POC-BG) data from the Medical Automation Systems RALS-Plus data management system to a central server. Analyses include the number of tests and the mean and median BG results for intensive care unit (ICU), non-ICU, and each hospital compared to the aggregate of the other hospitals.

Results

More than 175 million BG results were extracted from 2006–2009; 25% were from the ICU. Mean range of BG results for all inpatients in 2006, 2007, 2008, and 2009 was 142.2–201.9, 145.6–201.2, 140.6–205.7, and 140.7–202.4 mg/dl, respectively. The range for ICU patients was 128–226.5, 119.5–219.8, 121.6–226.0, and 121.1–217 mg/dl, respectively. The range for non-ICU patients was 143.4–195.5, 148.6–199.8, 145.2–201.9, and 140.7–203.6 mg/dl, respectively. Hyperglycemia rates of >180 mg/dl in 2008 and 2009 were examined, and hypoglycemia rates of <40 mg/dl (severe) and <70 mg/dl (moderate) in both 2008 and 2009 were calculated.

Conclusions

From these data, hospitals can determine the current state of glycemic control in their hospital and in comparison to other hospitals. For many, glycemic control has improved. Automated POC-BG data management software can assist in this effort.     

How continuous monitoring changes the interaction of patients with a mobile telemedicine system

Background

The combination of telemedicine systems integrating mobile technologies with the use of continuous glucose monitors improves patients’ glycemic control but demands a higher interaction with information technology tools that must be assessed. In this article, we analyze patients’ behavior from the use-of-the-system point of view, identifying how continuous monitoring may change the interaction of patients with the mobile telemedicine system.

Methods

Patients’ behavior were evaluated in a clinical experiment consisting of a 2-month crossover randomized study with 10 type 1 diabetes patients. During the entire experiment, patients used the DIABTel telemedicine system, and during the intervention phase, they wore a continuous glucose monitor. Throughout the experiment, all user actions were automatically registered. This article analyzes the occurrence of events and the behavior patterns in blood glucose (BG) self-monitoring and insulin adjustments. A subjective evaluation was also performed based on the answers of the patients to a questionnaire delivered at the end of the study.

Results

The number of sessions established with the mobile Smart Assistant was considerably higher during the intervention period than in the control period (29.0 versus 18.8, p < .05), and it was also higher than the number of Web sessions (29.0 versus 22.2, p < .01). The number of daily boluses was higher during the intervention period than in the control period (5.27 versus 4.40, p < .01). The number of daily BG measurements was also higher during the intervention period (4.68 versus 4.05, p < .05) and, in percentage, patients increased the BG measurements not associated to meals while decreasing the percentage of preprandial measurements. The subjective evaluation shows that patients would recommend the use of DIABTel in routine care.

Conclusions

The use of a continuous glucose monitor changes the way patients manage their diabetes, as observed in the increased number of daily insulin bolus, the increased number of daily BG measurements, and the differences in the distribution of BG measurements throughout the day. Continuous monitoring also increases the interaction of patients with the information system and modifies their patterns of use. We can conclude that mobile technologies are especially useful in scenarios of tight monitoring in diabetes, and they are well accepted by patients.     

Foot Technology, Part 1 of 2: Association between Foot Temperature and Sudomotor Dysfunction in Type 2 Diabetes

Background and Aims

Increased foot skin temperature has been described as a feature of diabetic neuropathy. The aim of this present study was to investigate the association between foot temperature and sudomotor dysfunction in type 2 diabetes mellitus.

Patients and Methods

This study included 51 patients (group A: 25 men, mean age 61.14 ± 6.11 years) without sudomotor dysfunction and 52 patients (group B: 25 men, mean age 59.54 ± 6.18 years) with sudomotor dysfunction. Sudomotor dysfunction was defined as time until complete Neuropad^® color change from blue to pink exceeding 600 s in at least one foot. Time until complete color change of the test was also recorded. Foot skin temperature was measured with a handheld infrared thermometer on the plantar aspect of the foot at the level of the first metatarsal head.

Results

On both feet, temperature was significantly higher in group B than in group A (right foot, group A versus group B, 30.62 ± 1.13 °C versus 32.12 ± 1.06 °C, p < .001; left foot, group A versus group B, 30.65 ± 1.06 °C versus 32.19 ± 1.10 °C, p < .001). There was a significant positive correlation between time to complete Neuropad color change and foot skin temperature (right foot, r = 0.742, p < .001; left foot, r = 0.758, p < .001), which was confirmed in both groups.

Conclusions

Patients with sudomotor dysfunction have significantly higher foot temperature than those without sudomotor dysfunction. Foot temperature is positively correlated with severity of sudomotor dysfunction, as evaluated by the time to complete Neuropad color change.     

Determinants of the accuracy of continuous glucose monitoring in non-critically ill patients with heart failure or severe hyperglycemia

Background

The accuracy of continuous glucose monitoring (CGM) in non-critically ill hospitalized patients with heart failure or severe hyperglycemia (SH) is unknown.

Methods

Hospitalized patients with congestive heart failure (CHF) exacerbation (receiving IV or subcutaneous insulin) or SH requiring insulin infusion were compared to outpatients referred for retrospective CGM.

Results

Forty-three patients with CHF, 15 patients with SH, and 88 outpatients yielded 470, 164, and 2150 meter–sensor pairs, respectively. Admission glucose differed (188 versus 509 mg/dl in CHF and SH, p < .001) but not the first sensor glucose (p = .35). In continuous glucose error grid analysis, 67–78% of pairs during hypoglycemia were in zones A+B (p = .63), compared with 98–100% in euglycemia (p < .001) and 98%, 92%, and 99% (p = .001) during hyperglycemia for the CHF, SH, and outpatient groups, respectively. Mean absolute relative difference (MARD) was lower in the CHF versus the SH group in glucose strata above 100 mg/dl, but there was no difference between the CHF and outpatient groups. Linear regression models showed that CHF versus outpatient, SH versus CHF, and coefficient of variation were significant predictors of higher MARD. Among subjects with CHF, MARD was not associated with brain natriuretic peptide or change in plasma volume, but it was significantly higher in subjects randomized to IV insulin (p = .04).

Conclusions

The results suggest that SH and glycemic variability are more important determinants of CGM accuracy than known CHF status alone in hospitalized patients.     

Diabetes Technologies and Hospital Care: Comparison of Insulin Pump Therapy (Continuous Subcutaneous Insulin Infusion) to Alternative Methods for Perioperative Glycemic Management in Patients with Planned Postoperative Admissions

Background

Patients with diabetes who use insulin pumps [continuous subcutaneous insulin infusion (CSII)] undergo surgeries that require postoperative hospital admission. There are no defined guidelines for CSII perioperative use.

Methods

This retrospective single-institution study identified type 1 and type 2 diabetes subjects by electronically searching 2005–2010 anesthesia preoperative assessments for “pump.” Surgical cases (n = 92) were grouped according to intraoperative insulin delivery method: (a) CSII continuation of basal rate with/without correctional insulin bolus(es) (n = 53); (b) conversion to intravenous insulin infusion (n = 20); and (c) CSII suspension with/without correctional insulin bolus(es) (n = 19). These groups were compared on mean intraoperative blood glucose (BG) and category of most extreme intraoperative BG.

Results

Differences were found on baseline characteristics of diabetes duration (p = .010), anesthesia time (p = .011), proportions receiving general anesthesia (p = .013), and preoperative BG (p = .033). The conversion group had the longest diabetes duration and anesthesia time; it had a higher proportion of general anesthesia recipients and a higher mean preoperative BG than the continuation group. There was no significant difference in mean BG/surgical case between continuation (163.5 ± 58.5 mg/dl), conversion (152.3 ± 28.9 mg/dl), and suspension groups (188.3 ± 44.9 mg/dl; p = .128). The suspension group experienced a greater percentage of cases (84.2%) with one or more intraoperative BG > 179 mg/dl than continuation (45.3%) and conversion (40%) groups Figure 1 groupings (p = .034).Open in a separate windowFigure 1Comparison of insulin delivery methods to percentage of surgical cases with intraoperative hypoglycemia and hyperglycemia. Chi-square = 13.43, p = .034; continuation group, n = 53; conversion group, n = 20; suspension group, n = 19. All groupings were mutually exclusive. Intraoperative BG is defined as all BG measurements performed in the operating room and the first postoperative anesthesia care unit measurement

Conclusions

In this limited sample, preliminary findings are consistent with similar intraoperative glycemic control between CSII continuation and CSII conversion to intravenous insulin infusions. Continuous subcutaneous insulin infusion suspension had a greater rate of hyperglycemia. Preoperative differences between insulin delivery groups complicate interpretations of findings.     

Effect of Insulin Feedback on Closed-Loop Glucose Control: A Crossover Study

Background

Closed-loop (CL) insulin delivery systems utilizing proportional-integral-derivative (PID) controllers have demonstrated susceptibility to late postprandial hypoglycemia because of delays between insulin delivery and blood glucose (BG) response. An insulin feedback (IFB) modification to the PID algorithm has been introduced to mitigate this risk. We examined the effect of IFB on CL BG control.

Methods

Using the Medtronic ePID CL system, four subjects were studied for 24 h on PID control and 24 h during a separate admission with the IFB modification (PID + IFB). Target glucose was 120 mg/dl; meals were served at 8:00 AM, 1:00 PM, and 6:00 PM and were identical for both admissions. No premeal manual boluses were given. Reference BG excursions, defined as incremental glucose rise from premeal to peak, and postprandial BG area under the curve (AUC; 0–5 h) were compared. Results are reported as mean ± standard deviation.

Results

The PID + IFB control resulted in higher mean BG levels compared with PID alone (153 ± 54 versus 133 ± 56 mg/dl; p < .0001). Postmeal BG excursions (114 ± 28 versus 114 ± 47 mg/dl) and AUCs (285 ± 102 versus 255 ± 129 mg/dl/h) were similar under both conditions. Total insulin delivery averaged 57 ± 20 U with PID versus 45 ± 13 U with PID + IFB (p = .18). Notably, eight hypoglycemic events (BG < 60 mg/dl) occurred during PID control versus none during PID + IFB.

Conclusions

Addition of IFB to the PID controller markedly reduced the occurrence of hypoglycemia without increasing meal-related glucose excursions. Higher average BG levels may be attributable to differences in the determination of system gain (Kp) in this study. The prevention of postprandial hypoglycemia suggests that the PID + IFB algorithm may allow for lower target glucose selection and improved overall glycemic control.