Optimizing Hospital Use of Intravenous Insulin Therapy: Improved Management of Hyperglycemia and Error Reduction With a New Nomogram

Evaluation of the Efficacy and Safety of an eGlycemic Management System in a Community Hospital Setting

BACKGROUND

Glucommander is an eGlycemic management system (eGMS) for intravenous (IV) and subcutaneous (SQ) insulin therapy in hospitalized patients. The purpose of this study was to evaluate the efficacy and safety of Glucommander compared to previously utilized nomograms in the community hospital setting.

METHODS

This study was a retrospective, single-center cohort study comparing measures of efficacy and safety of IV and SQ insulin therapy via eGMS versus nomogram-driven IV insulin therapy followed by provider-ordered basal-bolus SQ insulin. The primary efficacy endpoint was percent of blood glucose (BG) readings per patient in target glycemic range. Safety objectives were percent of hyperglycemic events, hypoglycemic events, and severe hypoglycemic events after achieving target blood glucose range, and mean number of each event per patient.

RESULTS

The percentage of BG readings in range was significantly higher for eGMS patients (n = 110) than comparison cohort patients (n = 108, 84.6% vs 76.8%, P < .001). Hyperglycemic events occurred for significantly fewer patients in the eGMS cohort relative to the comparison cohort (81.8% vs 92.6%, P = .03). Overall, there was no significant difference between cohorts in rate of hypoglycemic events, but hypoglycemic events while on IV insulin occurred in a significantly higher percentage of eGMS cohort patients than comparison cohort patients (30.9% vs 15.7%, P < .01). There were no significant differences in incidence of severe hypoglycemic events.

CONCLUSIONS

Our study found that Glucommander maintained a higher percentage of BG readings in target BG range per patient compared to previously utilized nomograms. This result was driven by an improvement in hyperglycemia, but not hypoglycemia.

Prospective evaluation of a dynamic insulin infusion algorithm for non critically-ill diabetic patients: A before-after study

INTRODUCTION

Insulin infusion is recommended during management of diabetic patients in critical care units to rapidly achieve glycaemic stability and reduce the mortality. The application of an easy-to-use standardized protocol, compatible with the workload is preferred. Glycaemic target must quickly be reached, therefore static algorithms should be replaced by dynamic ones. The dynamic algorithm seems closer to the physiological situation and appreciates insulin sensitivity. However, the protocol must meet both safety and efficiency requirements. Indeed, apprehension from hypoglycaemia is the main deadlock with the dynamic algorithms, thus their application remains limited. In contrary to the critical care units, to date, no prospective study evaluated a dynamic algorithm of insulin infusion in non-critically ill patients.

AIM

This study primarily aimed to evaluate the efficacy of a dynamic algorithm of intravenous insulin therapy in non-critically-ill patients, and addressed its safety and feasibility in different departments of our university hospital.

METHODS

A "before-after" study was conducted in five hospital departments (endocrinology and four "non-expert" units) comparing a dynamic algorithm (during the "after" period-P2) to the static protocol (the "before" period-P1). Static protocol is based on determining insulin infusion according to an instant blood glycaemia (BG) level at a given time. In the dynamic algorithm, insulin infusion rate is determined according to the rate of change of the BG (the previous and actual BG under a specific insulin infusion rate). Additionally, two distinct glycaemic targets were defined according to the patients' profile: 100-180 mg/dl (5.5-10 mmol/l) for vigorous patients and 140-220 mg/dl (7.8-12.2 mmol/l) for frail ones. Different BG measurements for each patient were collected and recorded in a specific database (e-CRF) in order to analyse the rates of hypo- and hyperglycaemia. A satisfaction survey was also performed. A study approval was obtained from the institutional revision board before starting the study.

RESULTS

Over 8 months, 72 and 66 patients during P1 and P2 were respectively included. The dynamic algorithm was more efficient, with reduced time to control hyperglycaemia (P1 vs P2:8.3 vs 5.3 hours; HR: 2.02 [1.27; 3.21]; p<0.01), increased the number of in-target BG measurements (P1 vs P2: 37.0% vs 41.8%; p<0.05), and reduced the glycaemic variability related to each patient (P1 vs P2, %CV: 40.9 vs 38.2;p<0.05, Index Correlation Class:0.30 vs 0.14; p<0.05). In patients after the first event of hypoglycemia after having started the infusion, new events were lower (P1 vs P2: 19.4 vs 11.4; p<0.001) thanks to an earlier reaction to hypoglycaemia (8.3% during P1 vs 44.3% during P2; p = 0.004). With the dynamic algorithm, the percentage of recurrence of mild hypoglycaemia was significantly lower in frail patients (20.5% vs 10.2%; p<0.001), and in patients managed in the non-expert units (18 vs 7.1%, p<0.001). The %CV was significantly improved in frail patients (36.9%). Mean BG measurements for each patient/day were 5.5±1.1 during P1 and 6.0±1.6 during P2 (p = 0.6). The threat from hypoglycaemia and the difficulty in using dynamic algorithm are barriers for nurses' adherence.

CONCLUSIONS

This dynamic algorithm for non-critically-ill patients is more efficient and safe than the static protocol, and adapted for frail patients and non-expert units.

Implementation of a New Intravenous Insulin Method on Intermediate-Care Units in Hospitalized Patients

Good blood glucose control in hospitalized adults leads to reduced mortality. Intravenous (IV) insulin has been shown to be an effective way to achieve tight control of blood glucose. Managing IV insulin is a labor-intensive task for nurses and is generally done in intensive care units with high nurse-to-patient ratios. In this 3-month study, intermediate-care general medicine units with a nurse-to-patient ratio of 1 to 5 or 6 were evaluated for effectiveness of monitoring IV insulin. The project, which relied on intensive in-service education, an audit tool, and continuous positive feedback for nurses, yielded positive results.

Transitioning safely from intravenous to subcutaneous insulin

The transition from intravenous (IV) to subcutaneous (SQ) insulin in the hospitalized patient with diabetes or hyperglycemia is a key step in patient care. This review article suggests a stepwise approach to the transition in order to promote safety and euglycemia. Important components of the transition include evaluating the patient and clinical situation for appropriateness, recognizing factors that influence a safe transition, calculation of proper SQ insulin doses, and deciding the appropriate type of SQ insulin. This article addresses other clinical situations including the management of patients previously on insulin pumps and recommendations for patients requiring glucocorticoids and enteral tube feedings. The use of institutional and computerized protocols is discussed. Further research is needed regarding the transition management of subgroups of patients such as those with type 1 diabetes and end-stage renal disease.

Evaluation of nursing adherence to a paper-based graduated continuous intravenous regular human insulin infusion algorithm

OBJECTIVE

The use of continuous intravenous regular human insulin (RHI) infusion is often necessary to achieve glycemic control in critically ill patients. Because insulin is a high-risk medication owing to the potential for severe hypoglycemia, it is imperative that insulin infusion algorithms are designed to be safe, effective, and instructionally clear. The safety and efficacy of our intravenous RHI infusion algorithm protocol has been previously established (Nutrition 2008;24:536-45); however, the protocol violations by nursing personnel were not examined. The objective of this study was to assess nursing adherence to our RHI infusion algorithm.

METHODS

Continuous RHI infusion algorithm violations were retrospectively evaluated in adult patients admitted to a trauma intensive care unit who received concurrent continuous enteral and/or parenteral nutrition therapy and our algorithm for at least 3 d. Blood glucose (BG) monitoring was done every 1 to 2 h with the target BG at 70 to 149 mg/dL (3.9 to 8.3 mmol/L). Nursing adherence to the RHI infusion protocol was evaluated for each patient by comparing the adjustments in insulin infusion rates documented by the nursing personnel with the prescribed adjustments per our graduated continuous intravenous RHI infusion algorithm.

RESULTS

A total of 4150 BG measurements necessitating the determination of the appropriate RHI dosage rate by nursing personnel in 40 patients occurred during the observational period. The target BG was achieved for a mean of 20 h/d and none of the patients had an episode of severe hypoglycemia (BG <40 mg/dL or 2.2 mmol/L). The overall rate of algorithm violations was 12.1%. The algorithm violations accounted for a single episode of mild to moderate hypoglycemia (BG 40 to 60 mg/dL or 2.2 to 3.3 mmol/L) in 4 patients and 65 total episodes of hyperglycemia (BG ≥150 mg/dL or 8.3 mmol/L) in 18 patients.

CONCLUSION

An adherence rate of nearly 90% is indicative of excellent nursing adherence compared with other published paper-based algorithms that examined protocol adherence. These data, combined with our previously published glycemic control data, indicate that this RHI infusion algorithm is an effective one for hyperglycemic trauma patients receiving continuous enteral and/or parenteral nutritional therapy.

Management of the hyperglycemic inpatient: tips, tools, and protocols for the clinician

Inpatient hyperglycemia is increasingly recognized as a contributor to in-hospital complications and prolonged hospital stays. Protocols to assist in management of hyperglycemia are becoming more widely used and have been shown to improve outcomes for hyperglycemic patients. In this article, several evidence-based protocols are reviewed for use by hospital-based clinicians, both for subcutaneous and intravenous insulin. Clinicians should consider implementing protocols for hyperglycemia management in the inpatient setting.

Comparisons of different insulin infusion protocols: a review of recent literature

PURPOSE OF REVIEW

To provide an update on the currently available insulin infusion protocols for treatment of hyperglycemia in critically ill patients and to discuss the major differences and similarities among them.

RECENT FINDINGS

We identified a total of 26 protocols, 20 of which used manual blood-glucose calculations, and six that used computerized algorithms. The major differences and similarities among the insulin infusion protocols were in the following areas: patient characteristics, target glucose level, time to achieve target glucose level, incidence of hypoglycemia, rationale for adjusting the rates of insulin infusion, and methods of blood-glucose measurements. Several computerized protocols hold promise for safer achievement of glycemic targets.

SUMMARY

Insulin infusion is the most effective method for controlling hyperglycemia in critically ill patients. Clinicians should utilize a validated insulin infusion protocol that is well tolerated, and is most appropriate and practical for their institution based on the resources that are available.

Pathway for the management of hyperglycemia in critical care units

Inhospital morbidity and mortality are increased in hyperglycemia. Normalization of blood glucose levels using intensive insulin infusion protocols improves clinical outcomes. Insulin infusion algorithms have been shown to be safe and effective; however, a major obstacle in their implementation is their complexity. We have developed a novel pathway for the management of hyperglycemia, which introduces the "wheel" concept for insulin dosing complemented by "catchup" insulin dosing. The "wheel" serves as a treatment guide. It is made up of 4 concentric circles. The inner circle features blood glucose ranges and the 3 outer circles correspond to increasing rates of insulin infusion. Simple guidelines are provided to facilitate conversion from insulin infusion to a subcutaneous insulin-delivery regimen in preparation for transfer from the critical care unit setting. Our protocols eliminate reliance on the familiar "sliding scale" insulin administration schemes with the introduction of "catchup" insulin dosing to supplement the basic regimen. This pathway is comprehensive yet simple and provides guidelines for treatment of hyperglycemia for all patients screened to a critical care unit or to a stepdown unit.

Delay in blood glucose monitoring during an insulin infusion protocol is associated with increased risk of hypoglycemia in intensive care units

BACKGROUND

Hypoglycemia during insulin infusion therapy is a major problem. We investigated whether a delay in blood glucose (BG) monitoring during an insulin infusion protocol (IIP) in the intensive care unit (ICU) is associated with hypoglycemia.

METHODS

Data were collected for 50 consecutive patients treated with Brigham and Women's Hospital's IIP. Point-of-care BG values were obtained from the bedside paper flow sheets and the exact times of individual measurements were ascertained from an internet-based glucose meter download program. Data were carefully studied for protocol time violations, defined as a delay of >10 minutes after the recommended time for BG measurement.

RESULTS

A total of 2309 BG values were evaluated for time violation. A total of 1474 (63.9%) measurements had been obtained at the recommended time or earlier; 835 (36.1%) measurements had been obtained >10 minutes after the recommended time for measurement. There were a significantly higher proportion of BG values <80 mg/dL following the time violation as compared to no time violation (17.8% versus 11.6%; P < 0.001).

CONCLUSION

We conclude that the risk of hypoglycemia during insulin infusion therapy is higher after a delay in BG measurement.

A systematic review on quality indicators for tight glycaemic control in critically ill patients: need for an unambiguous indicator reference subset

Introduction

The objectives of this study were to systematically identify and summarize quality indicators of tight glycaemic control in critically ill patients, and to inspect the applicability of their definitions.

Methods

We searched in MEDLINE^® for all studies evaluating a tight glycaemic control protocol and/or quality of glucose control that reported original data from a clinical trial or observational study on critically ill adult patients.

Results

Forty-nine studies met the inclusion criteria; 30 different indicators were extracted and categorized into four nonorthogonal categories: blood glucose zones (for example, 'hypoglycaemia'); blood glucose levels (for example, 'mean blood glucose level'); time intervals (for example, 'time to occurrence of an event'); and protocol characteristics (for example, 'blood glucose sampling frequency'). Hypoglycaemia-related indicators were used in 43 out of 49 studies, acting as a proxy for safety, but they employed many different definitions. Blood glucose level summaries were used in 41 out of 49 studies, reported as means and/or medians during the study period or at a certain time point (for example, the morning blood glucose level or blood glucose level upon starting insulin therapy). Time spent in the predefined blood glucose level range, time needed to reach the defined blood glucose level target, hyperglycaemia-related indicators and protocol-related indicators were other frequently used indicators. Most indicators differ in their definitions even when they are meant to measure the same underlying concept. More importantly, many definitions are not precise, prohibiting their applicability and hence the reproducibility and comparability of research results.

Conclusions

An unambiguous indicator reference subset is necessary. The result of this systematic review can be used as a starting point from which to develop a standard list of well defined indicators that are associated with clinical outcomes or that concur with clinicians' subjective views on the quality of the regulatory process.

Insulin infusion protocols for critically ill patients: a highlight of differences and similarities

OBJECTIVE

To discuss the major differences and similarities among the currently published insulin infusion protocols (IIPs) for critically ill patients.

METHODS

IIPs were identified by searching MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. The reference lists for all retrieved protocols were also reviewed to identify any IIPs that were not surfaced with use of our initial search strategies. The major differences and similarities among the IIPs were identified and examined. In addition, strategies for successful implementation of IIPs were outlined.

RESULTS

Our search strategies retrieved 17 IIPs. Currently, no published studies have compared one insulin protocol with another. The major differences or similarities among the published IIPs were in the following areas: patient characteristics, target glucose level, time to achieve target glucose level, incidence of hypoglycemia, rationale for adjusting the rates of insulin infusion, and methods of blood glucose measurements. Because of variations in the definition of hypoglycemia, methods of blood glucose measurement, and types of blood samples used, some comparisons across the protocols were difficult. Use of a multidisciplinary team and gaining administrative support are crucial for addressing issues and provision of necessary resources for implementing a protocol for "tight" glycemic control in critically ill patients.

CONCLUSION

Clinicians should evaluate the type of patients in their critical care units, the mean baseline glucose levels, and the available resources to determine the most appropriate and practical IIP for their institution.

Practical aspects of intensive insulinization in the intensive care unit

PURPOSE OF REVIEW

Strategies used for intensive insulin therapy of critically ill patients and differences of approach according to medical condition are reviewed.

RECENT FINDINGS

Acceptance of proposed glycemic targets for critically ill patients has been tempered by uncertainties about benefit of strict glycemic control for specific target subpopulations, differences between treatment centers, optimal timing and duration of intervention, and safety. Present-day intravenous insulin infusion protocols may perform well only for restricted populations. Assessment of protocol performance requires knowledge of algorithm behavior on or near the narrow target range and, using the patient as unit of observation, examination of glycemic variability. Systems of the future will permit adjustment of algorithm parameters to meet individual- or population-specific targets and match carbohydrate exposure.

SUMMARY

Attainment and preservation of glycemic control among critically ill patients are best attempted with intravenous insulin infusion. Advances in the design of decision support and insulin delivery systems, and progress in the technology of continuous blood glucose monitoring, are likely to reduce the risk of hypoglycemia, without compromise of target range control, such that the patient outcomes enjoyed by experienced centers in the future will prove generalizable to others through the extension of new technologies.

The Transition from Insulin Infusions to Long-Term Diabetes Therapy: The Argument for Insulin Analogs

After cardiac surgery, it is medical mismanagement to place an order for sliding scale insulin at the time of transitioning from intravenous insulin. Use of basal-prandial-correction therapy with insulin analogs constitutes a suitable transitioning regimen for inpatient management of hyperglycemia after heart surgery, to be ordered before interruption of intravenous insulin infusion, in conjunction with a program of blood glucose monitoring before meals, at bedtime, and midsleep. In the ambulatory setting, in comparison to neutral protamine Hagedorn, long-acting insulin analogs reduce hypoglycemia. In comparison to regular insulin, rapid-acting insulin analogs reduce hypoglycemia and improve postprandial control. A standardized approach to order entry for basal-prandial-correction therapy enhances safety and staff familiarity while preserving individualization of patient care. Proposed predictors of successful transition are described. Dose requirements during intravenous insulin infusion can be used to guide initial dose assignments of basal insulin therapy. As the patient approaches discharge, the total daily doses of subcutaneous insulin and basal insulin dose are decreased, and the proportion of prandial insulin approaches or exceeds 50% of the total daily dose as the absolute amount of prandial insulin increases. Before discharge, hyperglycemic patients not known to have diabetes should be advised of the need for outpatient reassessment, and those known to have diabetes but requiring intensification of therapy should participate in decision-making concerning their options for intensified treatment.

Performance of a dose-defining insulin infusion protocol among trauma service intensive care unit admissions

BACKGROUND

Among critically ill patients, glycemic control reduces mortality and morbidities, but the use of intravenous insulin infusion is complicated by hypoglycemia. Having a standardized algorithm increases the likelihood of effective and safe utilization of intravenous insulin therapy. A tabular dose-defining protocol for intravenous insulin infusion is described, containing design elements intended to minimize risk for hypoglycemia while seeking control in a narrow target range, and performance is evaluated among critically ill trauma service patients.

METHODS

The protocol assigns insulin infusion rate (IR) for ranges of blood glucose (BG). The columns are arranged in order of increasing maintenance rate (MR) for insulin infusion. Patient column assignment is determined according to rate of change of BG. During stable column assignment, the IR is a function of column MR and BG. Within-column, the protocol formula provides that (a) for BG between 70 mg/dL and target BG, the IR increases exponentially to the column MR; and (b) for BG above upper target BG range, the IR increases linearly as an adaptation of the rule of 1800, with slope determined by the column MR. Values for IR calculated by formula are rounded to correspond to BG ranges of the table. Performance was assessed in 27 sequential runs among 24 trauma service patients admitted to a surgical intensive care unit (2004-2005).

RESULTS

Using point-of-care measurements, mean preinfusion BG was 230.0 +/- 67.9 mg/dL. BG < 140 mg/dL was reached during all 27 runs (median time 5.0 h), and target BG was < 110 mg/dL during 25 runs (median time 11.0 h). For the group of runs attaining target before interruption of insulin infusion, the average +/- SD of the principal measure of glycemic control, the within-run mean BG, was 113.7 +/- 14.8 mg/dL (coefficient of variation 13%, n = 25 runs). After attaining target, the average within-run SD for BG was 22.9 mg/dL. The within-run frequency of hypoglycemic measurements (BG < 70 mg/dL) as a percentage of BG determinations was 2.4%. In this series, no instance of BG <50 mg/dL was seen.

CONCLUSIONS

This report describes a nurse-implemented tabular protocol for intravenous insulin infusion having the advantages of efficacy, safety, and simplicity of use. Wide variability of IR in the neighborhood of BG 110 mg/dL is associated with stable BG response, and protection against hypoglycemia is achieved by rapid decline of IR at BGs in or below the target range.