Intravenous insulin nomogram improves blood glucose control in the critically ill

Assessing glycemic variability in critically ill patients: A prospective cohort study comparing insulin infusion therapy with insulin sliding scale

Glycemic variability (GV) has been associated with an increased mortality rate among critically ill patients. The clinical outcomes of having less GV even with slight hyperglycemia are better than those having tight glycemic control but higher GV. Insulin infusion remains the preferred method to control stress hyperglycemia in critically ill patients. However, its impacts on GV and clinical outcomes in critically ill patients still need further investigation. This study intended to evaluate the impact of insulin infusion therapy (IIT) compared to the insulin sliding scale (ISS) on the extent of GV and explore its impact on the clinical outcomes for critically ill patients. A prospective, single-center observational cohort study was conducted at a tertiary academic hospital in Saudi Arabia between March 2021 and November 2021. The study included adult patients admitted to ICUs who received insulin for stress hyperglycemia management. Patients were categorized into two groups based on the regimen of insulin therapy during ICU stay (IIT versus ISS). The primary outcome was the GV between the two groups. Secondary outcomes were ICU mortality, the incidence of hypoglycemia, and ICU length of stay (LOS). A total of 381 patients were screened; out of them, eighty patients met the eligibility criteria. The distribution of patients having diabetes and a history of insulin use was similar between the two groups. The GV was lower in the IIT group compared to the ISS group using CONGA (- 0.65, 95% CI [- 1.16, - 0.14], p-value = 0.01). Compared with ISS, patients who received IIT had a lower incidence of hypoglycemia that required correction (6.8% vs 2.77%; p-value = 0.38). In contrast, there were no significant differences in ICU LOS and ICU mortality between the two groups. Our study demonstrated that the IIT is associated with decreased GV significantly in critically ill patients without increasing the incidence of severe hypoglycemia. There is no survival benefit with the use of the IIT. Further studies with larger sample size are required to confirm our findings and elaborate on IIT's potential effect in reducing ICU complications in critically ill patients.

American Association of Clinical Endocrinology Clinical Practice Guideline: Developing a Diabetes Mellitus Comprehensive Care Plan-2022 Update

OBJECTIVE

The objective of this clinical practice guideline is to provide updated and new evidence-based recommendations for the comprehensive care of persons with diabetes mellitus to clinicians, diabetes-care teams, other health care professionals and stakeholders, and individuals with diabetes and their caregivers.

METHODS

The American Association of Clinical Endocrinology selected a task force of medical experts and staff who updated and assessed clinical questions and recommendations from the prior 2015 version of this guideline and conducted literature searches for relevant scientific papers published from January 1, 2015, through May 15, 2022. Selected studies from results of literature searches composed the evidence base to update 2015 recommendations as well as to develop new recommendations based on review of clinical evidence, current practice, expertise, and consensus, according to established American Association of Clinical Endocrinology protocol for guideline development.

RESULTS

This guideline includes 170 updated and new evidence-based clinical practice recommendations for the comprehensive care of persons with diabetes. Recommendations are divided into four sections: (1) screening, diagnosis, glycemic targets, and glycemic monitoring; (2) comorbidities and complications, including obesity and management with lifestyle, nutrition, and bariatric surgery, hypertension, dyslipidemia, retinopathy, neuropathy, diabetic kidney disease, and cardiovascular disease; (3) management of prediabetes, type 2 diabetes with antihyperglycemic pharmacotherapy and glycemic targets, type 1 diabetes with insulin therapy, hypoglycemia, hospitalized persons, and women with diabetes in pregnancy; (4) education and new topics regarding diabetes and infertility, nutritional supplements, secondary diabetes, social determinants of health, and virtual care, as well as updated recommendations on cancer risk, nonpharmacologic components of pediatric care plans, depression, education and team approach, occupational risk, role of sleep medicine, and vaccinations in persons with diabetes.

CONCLUSIONS

This updated clinical practice guideline provides evidence-based recommendations to assist with person-centered, team-based clinical decision-making to improve the care of persons with diabetes mellitus.

Reference Ranges of Glycemic Variability in Infants after Surgery—A Prospective Cohort Study

We aimed to define reference ranges of glycemic variability indices derived from continuous glucose monitoring data for non-diabetic infants during post-operative intensive care treatment after cardiac surgery procedures. We performed a prospective cohort intervention study in a pediatric intensive care unit (PICU). Non-diabetic infants aged 0–12 months after corrective cardiovascular surgery procedures were fitted upon arrival to the PICU with a continuous glucose monitoring system (iPro2, Medtronic, Minneapolis, MN, USA). Thirteen glycemic variability indices were calculated for each patient. Complete recordings of 65 patients were collected on the first postoperative day. During the first three postsurgical days 5%, 24% and 43% of patients experienced at least one hypoglycemia episode, and 40%, 10% and 15%—hyperglycemia episode, respectively, in each day. Due to significant differences between the first postoperative day (mean glycemia 130 ± 31 mg/dL) and the second and third day (105 ± 18 mg/dL, 101 ± 22.2 mg/dL; p < 0.0001), we proposed two separate reference ranges—for the acute and steady state patients. Thus, for individual glucose measurements, we proposed a reference range between 85 and 229 mg/dL and 69 and 149 mg/dL. For the mean daily glucose level, ranges between 122 and 137 mg/dL and 95 and 110 mg/dL were proposed. In conclusion, rt-CGM revealed a very high likelihood of hyperglycemia in the first postsurgical day. The widespread use of CGM systems in a pediatric ICU setting should be considered as a safeguard against dysglycemic episodes; however, reference ranges for those patients should be different to those used in diabetes care.

Development and Validation of a Nomogram Incorporating Colloid Osmotic Pressure for Predicting Mortality in Critically Ill Neurological Patients

Backgrounds: The plasma colloid osmotic pressure (COP) values for predicting mortality are not well-estimated. A user-friendly nomogram could predict mortality by incorporating clinical factors and scoring systems to facilitate physicians modify decision-making when caring for patients with serious neurological conditions.

Methods: Patients were prospectively recruited from March 2017 to September 2018 from a tertiary hospital to establish the development cohort for the internal test of the nomogram, while patients recruited from October 2018 to June 2019 from another tertiary hospital prospectively constituted the validation cohort for the external validation of the nomogram. A multivariate logistic regression analysis was performed in the development cohort using a backward stepwise method to determine the best-fit model for the nomogram. The nomogram was subsequently validated in an independent external validation cohort for discrimination and calibration. A decision-curve analysis was also performed to evaluate the net benefit of the insertion decision using the nomogram.

Results: A total of 280 patients were enrolled in the development cohort, of whom 42 (15.0%) died, whereas 237 patients were enrolled in the validation cohort, of which 43 (18.1%) died. COP, neurological pathogenesis and Acute Physiology and Chronic Health Evaluation II (APACHE II) score were predictors in the prediction nomogram. The derived cohort demonstrated good discriminative ability, and the area under the receiver operating characteristic curve (AUC) was 0.895 [95% confidence interval (CI), 0.840–0.951], showing good correction ability. The application of this nomogram to the validation cohort also provided good discrimination, with an AUC of 0.934 (95% CI, 0.892–0.976) and good calibration. The decision-curve analysis of this nomogram showed a better net benefit.

Conclusions : A prediction nomogram incorporating COP, neurological pathogenesis and APACHE II score could be convenient in predicting mortality for critically ill neurological patients.

Implementing Intensive Insulin Therapy: Development and Audit of the Bath Insulin Protocol

Intensive insulin therapy to control blood glucose has been found to reduce mortality among critically ill patients in a surgical intensive care unit, though a simple prescriptive insulin infusion protocol to achieve this has not been published previously. This study documents the development and routine use of a simple prescriptive intravenous insulin infusion protocol for critically ill patients and compares the results with previous practice. During development the protocol was optimized and practical issues of implementation addressed. The optimized protocol was then used for all ICU admissions, and a prospectively defined retrospective chart audit performed for the first month of use. Results were compared with a similar time period the previous year. In September 2002, 27 admissions were started on the protocol. Blood glucose for the time on the protocol had a median value of 6.2 (IQR 5.9-7.1) mmol/l compared with 9.2 (IQR 8.1-10.2) mmol/l for those on insulin in 2001. Blood glucose for the whole ICU stay for those on the protocol in 2002 had a median value of 6.6 (IQR 6.0-7.4) mmol/l compared with 8.6 (IQR 8.0-9.4) mmol/l in 2001. Blood glucose for all ICU patients in 2002 had a median value of 6.5 (IQR 6.0-7.3) mmol/l compared with 7.2 (IQR 6.3-8.3) mmol/l in 2001.

Three blood glucose recordings were less than 2.2 mmol/l in September 2002. This study provides initial effectiveness and safety data for the Bath Insulin Protocol. Further audits in a larger patient population are now needed.

Development and validation of a nomogram for predicting self-propelled postpyloric placement of spiral nasoenteric tube in the critically ill: Mixed retrospective and prospective cohort study

BACKGROUND & AIMS

Equipment-aided or experience-dependent methods for postpyloric nasoenteric tube placement are not so readily accessible in the critically ill setting. Self-propelled postpyloric placement of a spiral nasoenteric tube can serve as an alternative approach. However, the success rate of this method is relatively low despite using prokinetics. This study aims to develop a user-friendly nomogram incorporating clinical markers to individually predict the probability of successful postpyloric nasoenteric tube placement and facilitate intensivists with improved decision-making before tube insertion.

METHODS

Patients consecutively recruited in the stage between May 2012 through December 2016 constituted the development cohort for retrospective analysis to internally test the nomogram, and patients in the stage between January 2017 through March 2018 constituted the validation cohort for prospective analysis to external validate the nomogram. A multivariate logistic regression analysis was firstly performed in the development cohort by a backward stepwise method to identify the best-fit model, from which a nomogram was obtained. The nomogram was validated in the independent external validation cohort concerning discrimination, calibration. A decision curve analysis was also performed to evaluate the net benefit of insertion decision with the nomogram.

RESULTS

A total of 364 and 119 patients, 52.7% and 55.5% with successful postpyloric placement, were included in the development and validation cohort, respectively. Predictors contained in the prediction nomogram included primary diagnosis, APACHE II score, AGI grade. The derived model showed good discrimination, with an area under the receiver operating characteristic curve (AUROC) of 0.809 (95%CI, 0.765-0.853) and good calibration. Application of the nomogram in the validation cohort also gave good discrimination with an AUROC of 0.776 (95%CI, 0.694-0.859) and good calibration. The decision curve analysis of the nomogram provided better net benefit than the alternate options (insert-all or insert-none).

CONCLUSIONS

A prediction nomogram that incorporates primary diagnosis, together with APACHE II score and AGI grade can be conveniently used to facilitate the pre-insertion individualized prediction of postpyloric nasoenteric tube placement in critically ill patients.

Glargine Insulin Use Versus Continuous Regular Insulin in Diabetic Surgical Noncritically Ill Patients Receiving Parenteral Nutrition: Randomized Controlled Study

BACKGROUND

Hyperglycemia is a major complication of parenteral nutrition (PN). Guidelines for hyperglycemia management in noncritically ill patients cite basal insulin administration but do not recommend a regimen. The GLUCOSE-in-PN study aimed to compare the efficacy of glargine insulin versus continuously infused regular insulin in PN (RI-in-PN) to achieve glycemic control in noncritically ill surgical patients with diabetes who were receiving PN.

METHODS

This prospective randomized open-label study was conducted at King Faisal Specialist Hospital and Research Centre. Noncritically ill surgical patients with diabetes who were receiving PN were randomized to receive basal glargine insulin or RI-in-PN on day 4 of PN support. Mean blood glucose levels were compared on study days 5-9. The percentages of blood glucose measurements at goal were compared between groups.

RESULTS

Sixty-seven PN treatment episodes were analyzed. There were no statistically significant differences in mean glucose levels between groups on any study day ( P > .1). Overall glycemic control rates were 52.24% (glargine insulin) and 47.76% (RI-in-PN; P = .06). A significantly higher percentage of hyperglycemia was observed on day 5 for glargine insulin versus RI-in-PN (22.39% vs 5.97%, P = .0059). Blood glucose measurements indicated 6 hypoglycemic events: 2 for glargine insulin (5.7%) and 4 for RI-in-PN (11.4%; P > .1).

CONCLUSION

Both glargine insulin and RI-in-PN are effective basal insulin modalities for blood glucose control in noncritically ill surgical patients with diabetes who are receiving PN. Uncontrolled hyperglycemic events occurred more frequently with glargine insulin, and the rate of hypoglycemia was acceptable for both regimens.

Association Between Perioperative Hyperglycemia or Glucose Variability and Postoperative Acute Kidney Injury After Liver Transplantation: A Retrospective Observational Study

BACKGROUND

Glucose control can be difficult in the intraoperative and immediate postoperative period of liver transplantation. Hyperglycemia and glucose variability have been associated with acute kidney injury (AKI) in critically ill patients. We performed a retrospective study to test the hypothesis that perioperative glucose levels represented by time-weighted average glucose levels and glucose variability are independently associated with the incidence of postoperative AKI in patients undergoing liver transplantation.

METHODS

On the basis of blood glucose levels during liver transplantation and the initial 48 hours postoperatively, adult liver transplant recipients were classified into 4 groups according to their time-weighted average glucose: normoglycemia (80-200 mg/dL), mild hyperglycemia (200-250 mg/dL), moderate hyperglycemia (250-300 mg/dL), and severe hyperglycemia (>300 mg/dL) group. Patients were also classified into quartiles depending on their glucose variability, defined as the standard deviation of glucose measurements. The primary outcome was postoperative AKI.

RESULTS

AKI after liver transplantation was more common in the patients with greater perioperative glucose variability (first versus third quartile; OR, 2.47 [95%CI, 1.22-5.00], P = .012; first versus fourth quartile; OR, 2.16 [95% CI, 1.05-4.42], P = .035).

CONCLUSIONS

Our study suggests that increased perioperative glucose variability, but not hyperglycemia, is independently associated with increased risk of postoperative AKI in liver transplantation recipients.

A Pilot Study to Evaluate the Effectiveness of Glargine and Multiple Injections of Lispro in Patients With Type 2 Diabetes Receiving Tube Feedings in a Cardiovascular Intensive Care Unit

BACKGROUND

The purpose of this study was to evaluate the effectiveness of insulin lispro and insulin glargine at controlling blood glucose in patients with type 2 diabetes mellitus in a cardiovascular intensive care unit (CICU) and receiving enteral tube feedings.

METHODS

This was a pilot study with a retrospective control designed to evaluate an insulin protocol in patients admitted to the CICU in a level 3 teaching institution. Patients were 18-99 years of age with type 2 diabetes mellitus, receiving bolus tube feeding. The control group included 24 patients who were retrospectively studied to determine mean blood glucose level. A glycemic management protocol was developed that included glargine and lispro insulins to maintain blood glucose levels between 80 and 140 mg/dL. The study group consisted of 28 patients who were treated according to the glycemic management protocol.

RESULTS

The mean blood glucose level of the retrospective control group was 225 mg/dL. The mean blood glucose level of the intervention group was 148 mg/dL. After protocol institution, 48.6% of blood glucose levels were within the goal blood glucose range of 80-140 mg/dL vs 8.26% (p = .01) before protocol institution. Hyperglycemia decreased from 90.0% to 47.2% (p < .0001) with institution of the protocol.

CONCLUSIONS

The average blood glucose of the intervention group was slightly above the goal blood glucose range of 80-140 mg/dL; however, the study protocol was superior to the previous CICU blood glucose management protocol.

[Metabolic control in the critically ill patient an update: hyperglycemia, glucose variability hypoglycemia and relative hypoglycemia]

BACKGROUND

Metabolic changes of glucose in critically ill patients increase morbidity and mortality. The appropriate level of blood glucose has not been established so far and should be adjusted for different populations. However concepts such as glucose variability and relative hypoglycemia of critically ill patients are concepts that are changing management methods and achieving closer monitoring.

OBJECTIVES

The purpose of this review is to present new data about the management and metabolic control of patients in critical areas.

CONCLUSIONS

Currently glucose can no longer be regarded as an innocent element in critical patients; both hyperglycemia and hypoglycemia increase morbidity and mortality of patients. Protocols and better instruments for continuous measurement are necessary to achieve the metabolic control of our patients.

Improving Hyperglycemia Management in the Intensive Care Unit

Purpose

The purpose of this study was to assess the feasibility of a nurse-driven effort to improve hyperglycemia management in the intensive care unit (ICU) setting.

Methods

The setting was the ICU of a large urban hospital. The program was composed of 3 components: nurses as leaders, a clinical pathway to identify patients in need of hyperglycemia therapy, and implementation of a redesigned insulin infusion algorithm (the Columnar Insulin Dosing Chart). Time to reach a target glucose range of 80 to 110 mg/dL (4.4-6.1 mmol/L) was evaluated.

Results

One hundred sixteen ICU nurses were trained in the project. The Columnar Insulin Dosing Chart was applied to 20 patients. The average time required to reach the target blood glucose range was 12.8 hours. Below-target blood glucose levels were 6.9% of all blood glucose levels recorded, but only 0.9% were below 60 mg/dL (3.3 mmol/L). There was no sustained hypoglycemia, and no persistent clinical findings attributable to hypoglycemia were noted. Barriers to implementing the project included an increased nursing workload, the need for more finger-stick blood glucose monitors, and the need to acquire new finger-lancing devices that allowed for shallower skin puncture and increased patient comfort.

Conclusions

Tighter glycemic control goals can be attained in a busy ICU by a nurse-led team using a pathway for identifying and treating hyperglycemia, clear decision support tools, and adequate nurse education. The novel chart based insulin infusion algorithm chosen as the standard for this pilot was an effective tool for reducing the blood glucose to target range with no clinically significant hypoglycemia.

Effectiveness of regular versus glargine insulin in stable critical care patients receiving parenteral nutrition: a randomized controlled trial

STUDY OBJECTIVE

To compare the effectiveness and safety of two glycemic control regimens in stable critical care patients receiving parenteral nutrition (PN).

DESIGN

Prospective, randomized open-label clinical trial.

METHODS

Eligible postoperative critical care patients in the ICU began PN on the first to the seventh day of ICU admission. The PN admixture included regular insulin, in doses sufficient to maintain 3 or more goal blood glucose (BG) levels between 110 and 180 mg/dl. After 3 to 5 days of PN containing regular insulin, patients were randomized to 3 more days of regular insulin at the same dose or 80% of their total daily regular insulin dose provided in PN solution as glargine insulin. Capillary BG monitoring was performed every 6 hours.

RESULTS

Twenty one patients were randomized to each treatment group. Median APACHE II scores were not significantly different between the two groups within the first 24-hour of ICU admission. There were no significant differences between the two groups at day 3 for mean daily dextrose (306.9 ± 46.2 vs. 305.2 ± 52.2 g; p=0.913) or insulin (18.3 ± 8.8 vs. 19.5 ± 10.0 units; p=0.696) doses. The percentage of BG values in the goal (110-180 mg/dl), hyperglycemic (> 180 mg/dl), and hypoglycemic (< 70 mg/dl) BG levels were similar between the two groups (69.0% vs. 66.7%, p=0.567; 11.9% vs. 11.1%, p=0.780; 0% vs. 1.6%, p=0.124, respectively). Mean daily BG levels were not significantly different between the two groups on each of the 3 study days (day 1: 140 ± 20 vs. 131 ± 25 mg/dl, p=0.194; day 2: 136 ± 20 vs. 140 ± 18 mg/dl, p=0.498; day 3: 142 ± 15 vs. 140 ± 19 mg/dl; p=0.741).

CONCLUSION

These data suggest that, compared with regular insulin added to PN, glargine insulin results in similar glycemic control and rates of hyperglycemia and hypoglycemia in stable critical care patients.

Intensive insulin therapy implementation by means of planned versus emergent change approach

BACKGROUND

Nurses' participation in decisions about new care procedures and protocols is potentially of benefit for patient outcomes. Whether nurses' participation in decisions is allowed in the implementation of innovations depends on the implementation approach used for the introduction. A planned change implementation approach does not allow it, an emergent change implementation approach does.

AIM

To compare a planned change and an emergent change implementation approach to introduce an intensive insulin therapy to an intensive care unit (ICU).

DESIGN

A prospective comparative study in an ICU in the Netherlands of two teams of nurses using either implementation approach.

METHODS

Pre-introduction of the comparability of the two teams was assessed. The nurse compliance to the protocol was assessed as being nurses' behaviour according to the protocol and leading to acceptable glucose values. The effectiveness of the implementation was assessed by measuring the percentage of patients' glucose values within the target range, the occurrence of hypoglycaemic events and the time to glucose value normalization. Data were collected from December 2007 till January 2009.

RESULTS

In the emergent change approach team there was better nurse compliance measurements than in the planned change approach team (83.5% vs 66,8% conform protocol), a better percentage of glucose values in the target range (53,5% vs 52.8%) and a shorter time to glucose value normalization.

CONCLUSION

The implementation approach allowing nurse participation was associated with better nurse compliance and patient outcome measurements. The implementation approach did not conflict with introducing an evidence-based innovation. It was also associated with more effective adaptation of the protocol to changing circumstances.

RELEVANCE FOR CLINICAL PRACTICE

When a new treatment requires adaptability to changing circumstances to be most effective, nurses' participation in decisions about the implementation of the treatment should be considered.

Effects of computerized decision support systems on blood glucose regulation in critically ill surgical patients

BACKGROUND

The use of computerized decision support systems (CDSS) in glucose control for critically ill surgical patients has been reported in both diabetic and nondiabetic patients. Prospective studies evaluating its effect on glucose control are, however, lacking. The objective of this study was to evaluate patient-specific computerized IV insulin dosing on blood glucose levels (BGLs) by comparing patients treated pre-CDSS with those treated post-CDSS.

STUDY DESIGN

A prospective study was performed in 4 surgical ICUs and 1 progressive care unit comparing patient data pre- and post-implementation of CDSS. The primary outcomes measures were the impact of the CDSS on glycemic control in this population and on reducing the incidence of severe hypoglycemia.

RESULTS

Data on 1,682 patient admissions were evaluated, which corresponded to 73,290 BGLs post-CDSS compared with 44,972 BGLs pre-CDSS. The percentage of hyperglycemic events improved, with BGLs of >150 mg/dL decreasing by 50% compared with 6-month historical controls during the 18-month study period from July 2010 through December 2011. This was true for all 5 units individually (p < 0.0001, by one sample sign test). In addition, severe hypoglycemia (defined as BGL <40 mg/dL) decreased from 1% to 0.05% after implementing CDSS (p < 0.0001 by 2-sided binomial test).

CONCLUSIONS

Patients whose BGLs were managed using CDSS were statistically significantly more likely to have a glucose reading under control (<150 mg/dL) than in the 6-month historical controls and to avoid serious hypoglycemia (p < 0.0001).

Guidelines for the use of an insulin infusion for the management of hyperglycemia in critically ill patients

OBJECTIVE

To evaluate the literature and identify important aspects of insulin therapy that facilitate safe and effective infusion therapy for a defined glycemic end point.

METHODS

Where available, the literature was evaluated using Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) methodology to assess the impact of insulin infusions on outcome for general intensive care unit patients and those in specific subsets of neurologic injury, traumatic injury, and cardiovascular surgery. Elements that contribute to safe and effective insulin infusion therapy were determined through literature review and expert opinion. The majority of the literature supporting the use of insulin infusion therapy for critically ill patients lacks adequate strength to support more than weak recommendations, termed suggestions, such that the difference between desirable and undesirable effect of a given intervention is not always clear.

RECOMMENDATIONS

The article is focused on a suggested glycemic control end point such that a blood glucose ≥ 150 mg/dL triggers interventions to maintain blood glucose below that level and absolutely <180 mg/dL. There is a slight reduction in mortality with this treatment end point for general intensive care unit patients and reductions in morbidity for perioperative patients, postoperative cardiac surgery patients, post-traumatic injury patients, and neurologic injury patients. We suggest that the insulin regimen and monitoring system be designed to avoid and detect hypoglycemia (blood glucose ≤ 70 mg/dL) and to minimize glycemic variability.Important processes of care for insulin therapy include use of a reliable insulin infusion protocol, frequent blood glucose monitoring, and avoidance of finger-stick glucose testing through the use of arterial or venous glucose samples. The essential components of an insulin infusion system include use of a validated insulin titration program, availability of appropriate staffing resources, accurate monitoring technology, and standardized approaches to infusion preparation, provision of consistent carbohydrate calories and nutritional support, and dextrose replacement for hypoglycemia prevention and treatment. Quality improvement of glycemic management programs should include analysis of hypoglycemia rates, run charts of glucose values <150 and 180 mg/dL. The literature is inadequate to support recommendations regarding glycemic control in pediatric patients.

CONCLUSIONS

While the benefits of tight glycemic control have not been definitive, there are patients who will receive insulin infusion therapy, and the suggestions in this article provide the structure for safe and effective use of this therapy.

Protocol-directed insulin infusion sliding scales improve perioperative hyperglycaemia in critical care

Perioperative hyperglycaemia is associated with poor outcomes in patients undergoing cardiac surgery. Frequent postoperative hyperglycaemia in cardiac surgery patients has led to the initiation of an insulin infusion sliding scale for quality improvement.

A systematic review was conducted to determine whether a protocol-directed insulin infusion sliding scale is as safe and effective as a conventional practitioner-directed insulin infusion sliding scale, within target blood glucose ranges.

A literature survey was conducted to identify reports on the effectiveness and safety of an insulin infusion protocol, using seven electronic databases from 2000 to 2012: MEDLINE, CINAHL, EMBASE, the Cochrane Library, the Joanna Briggs Institute Library and SIGLE. Data were extracted using pre-determined systematic review and meta-analysis criteria.

Seven research studies met the inclusion criteria. There was an improvement in overall glycaemic control in five of these studies. The implementation of protocols led to the achievement of blood glucose concentration targets more rapidly and the maintenance of a specified target blood glucose range for a longer time, without any increased frequency of hyperglycaemia. Of the seven studies, four used controls and three had no controls.

In terms of the meta-analysis carried out, four studies revealed a failure of patients reaching target blood glucose levels (P < 0.0005) in the control group compared with patients in the protocol group. The risk of hypoglycaemia was significantly reduced (P <0.00001) between studies.

It can be concluded that the protocol-directed insulin infusion sliding scale is safe and improves blood glucose control when compared with the conventional practitioner-directed insulin infusion sliding scale. This study supports the adoption of a protocol-directed insulin infusion sliding scale as a standard of care for post-cardiac surgery patients.

Continuous glucose monitoring in patients undergoing cardiac surgery

OBJECTIVES

Hyperglycemia is a prominent feature among patients exposed to major stress such as in cardiac surgery. The implementation of a continuous glucose monitoring system (CGMS) for glucose monitoring during cardiac surgery was assessed.

SUBJECTS AND METHODS

Fifty-nine consecutive patients who underwent cardiac surgery were monitored by CGMS. Patients' fluid glucose content, drug requirements, and hemodynamic and physiologic parameters were evaluated.

RESULTS

Of the 59 patients, 32 completed the monitoring with CGMS. Patients were divided into three groups: diabetes patients, patients without diabetes history who developed significant hyperglycemia perioperatively, and patients who did not develop hyperglycemia. Hyperglycemia was most frequently observed postoperatively. Hyperglycemic patients required significantly more insulin (81±40 vs. 34±37 units, P=0.005) and experienced an increased early complication rate, although this difference was not significant. CGMS erroneously detected late-phase operative and immediate postoperative hypoglycemia in approximately one-third of patients as reflected from venous blood sample measurements.

CONCLUSIONS

CGMS enables close monitoring and optimal control of blood glucose among patients undergoing major cardiac surgery, although its reliability is limited during the cardiac surgery phase and in the early postoperative period, because of incorrect hypoglycemic readings.

Glycemic control in critically ill patients

Hyperglycemia is common in critically ill patients and can be caused by various mechanisms, including nutrition, medications, and insufficient insulin. In the past, hyperglycemia was thought to be an adaptive response to stress, but hyperglycemia is no longer considered a benign condition in patients with critical illnesses. Indeed, hyperglycemia can increase morbidity and mortality in critically ill patients. Correction of hyperglycemia may improve clinical outcomes. To date, a definite answer with regard to glucose management in general intensive care unit patients, including treatment thresholds and glucose target is undetermined. Meta-analyses of randomized controlled trials suggested no survival benefit of tight glycemic control and a significantly increased incidence of hypoglycemia. Studies have shown a J- or U-shaped relationship between average glucose values and mortality; maintaining glucose levels between 100 and 150 mg/dL was likely to be associated with the lowest mortality rates. Recent studies have shown glycemic control < 180 mg/dL is not inferior to near-normal glycemia in critically ill patients and is clearly safer. Glycemic variability is also an important aspect of glucose management in the critically ill patients. Higher glycemic variability may increase the mortality rate, even in patients with the same mean glucose level. Decreasing glucose variability is an important issue for glycemic control in critically ill patients. Continuous measurements with automatic closed-loop systems could be considered to ensure that blood glucose levels are controlled within a specific range and with minimal variability.

Management of hyperglycemia during the perioperative period

Hyperglycemia is frequently encountered in the inpatient setting and is distinctly associated with poor clinical outcomes. Recent literature suggests an association between stringent glycemic control and increased mortality, thus keeping optimal glycemic targets a relevant subject of debate. In the surgical population, hyperglycemia with or without diabetes mellitus may be unrecognized. Factors contributing to hyperglycemia in the hospital include critical illness, use of certain drugs, use of enteral or parenteral nutrition, and variability in oral or nutritional intake as can occur when patients are prepared for procedures or surgery. A sensible approach to managing hyperglycemia in this population includes preoperative recognition of diabetes mellitus and risks for inpatient hyperglycemia. Judicious control of glycemia during the pre-, intra-, and postoperative time periods with avoidance of hypoglycemia mandates the need for a strategy for patient management that extend to time of discharge. We review the consequences of uncontrolled perioperative hyperglycemia, discuss current clinical guidelines and recent controversies, and provide practical tools for glycemic control in the surgical population.

Management of hyperglycemia in hospitalized patients

Hyperglycemia is a common occurrence in hospitalized patients, and several studies have shown a strong association between hyperglycemia and the risk of complications, prolonged hospitalization, and death for patients with and without diabetes. Past studies have shown that glucose management in the intensive care setting improves clinical outcomes by reducing the risk of multiorgan failure, systemic infection, and mortality, and that the importance of hyperglycemia also applies to noncritically ill patients. Based on several past observational and interventional studies, aggressive control of blood glucose had been recommended for most adult patients with critical illness. Recent randomized controlled trials, however, have shown that aggressive glycemic control compared to conventional control with higher blood glucose targets is associated with an increased risk of hypoglycemia and may not result in the improvement in clinical outcomes. This review aims to give an overview of the evidence for tight glycemic control (blood glucose targets <140 mg/dL), the evidence against tight glycemic control, and the updated recommendations for the inpatient management of diabetes in the critical care setting and in the general wards.

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.

Intensive insulin treatment improves forearm blood flow in critically ill patients: a randomized parallel design clinical trial

INTRODUCTION

Intensive insulin treatment of critically ill patients was seen as a promising method of treatment, though recent studies showed that reducing the blood glucose level below 6 mmol/l had a detrimental outcome. The mechanisms of the effects of insulin in the critically ill are not completely understood. The purpose of the study was to test the hypothesis that intensive insulin treatment may influence forearm blood flow independently of global hemodynamic indicators.

METHODS

The study encompassed 29 patients of both sexes who were admitted to the intensive care unit due to sepsis and required artificial ventilation as the result of acute respiratory failure. 14 patients were randomly selected for intensive insulin treatment (Group 1; blood glucose concentration 4.4-6.1 mmol/l), and 15 were selected for conventional insulin treatment (Group 2; blood glucose level 7.0 mmol/l-11.0 mmol/l). At the start of the study (t0, beginning up to 48 hours after admittance and the commencement of artificial ventilation), at 2 hours (t1), 24 hours (t2), and 72 hours (t3) flow in the forearm was measured for 60 minutes using the strain-gauge plethysmography method. Student's t-test of independent samples was used for comparisons between the two groups, and Mann-Whitney's U-test where appropriate. Linear regression analysis and the Pearson correlation coefficient were used to determine the levels of correlation.

RESULTS

The difference in 60-minute forearm flow at the start of the study (t0) was not statistically significant between groups, while at t2 and t3 significantly higher values were recorded in Group 1 (t2; Group 1: 420.6 +/- 188.8 ml/100 ml tissue; Group 2: 266.1 +/- 122.2 ml/100 ml tissue (95% CI 30.9-278.0, P = 0.02); t3; Group 1: 369.9 +/- 150.3 ml/100 ml tissue; Group 2: 272.6 +/- 85.7 ml/100 ml tissue (95% CI 5.4-190.0, P = 0.04). At t1 a trend towards significantly higher values in Group 1 was noted (P = 0.05). The level of forearm flow was related to the amount of insulin infusion (r = 0.40).

CONCLUSIONS

Compared to standard treatment, intensive insulin treatment of critically ill patients increases forearm flow. Flow increase was weakly related to the insulin dose, though not to blood glucose concentration.

TRIAL REGISTRATION

TRIAL NUMBER

ISRCTN39026810.

Glycemic control in the medical intensive care unit

Hyperglycemia in the critically ill is a well-known phenomenon, even in those without known diabetes. The stress response is due to a complex interplay between counter-regulatory hormones, cytokines, and changes in insulin sensitivity. Illness/infection, overfeeding, medications (e.g., corticosteroids), insufficient insulin, and/or volume depletion can be additional contributors. Acute hyperglycemia can adversely affect fluid balance (through glycosuria and dehydration), immune and endothelial function, inflammation, and outcome. While there are several insulin infusion protocols that are able to safely and effectively treat hyperglycemia, the bulk of accumulated evidence does not support a causal relationship between acute hyperglycemia and adverse outcomes in the medical intensive care unit. Meta-analysis of randomized controlled trials suggests there is no benefit to tightening glucose control to normal levels compared to a reasonable and achievable goal of 140 to 180 mg/dl. There is a significantly increased risk of hypoglycemia. Although there is some evidence that patients without known diabetes have worse outcomes than those with known diabetes, more recent evidence is conflicting. Glycemic control in critically ill patients should not be neglected, as studies have not tested tight versus no/poor control, but tight versus good control. A moderate approach to managing critical illness hyperglycemia seems most prudent at this juncture. Future research should ascertain whether there are certain subgroups of patients that would benefit from tighter glycemic goals. It also remains to be seen if tight glucose control is beneficial once hypoglycemia is minimized with technological advances such as continuous glucose monitoring systems.

Insulin strategies for managing inpatient and outpatient hyperglycemia and diabetes

Optimal fasting and postprandial glycemic control are essential to limiting microvascular and macrovascular complications associated with diabetes. Recently, stringent control of hyperglycemia in critically ill hospitalized patients with diabetes or acute hyperglycemia has been shown to reduce the risk of morbidity and mortality. This article reviews effective strategies for insulin initiation, titration, and intensification in inpatient and outpatient settings and discusses current treatment strategies when patients are being transitioned from the intensive care unit to general wards and discharged. The development of insulin analogs and premixed insulin analogs has created new options for treating inpatients and outpatients. The more physiologic time-action profiles, improved insulin delivery systems, and standardized protocols for subcutaneous insulin administration and intravenous insulin infusion have improved the safety and convenience of insulin therapy.

Recognizing and preventing refeeding syndrome

Refeeding syndrome is an uncommon but potentially fatal phenomenon that can occur in patients receiving parenteral, enteral, or oral feedings after a period of sustained malnutrition or starvation. This syndrome is characterized by hypophosphatemia, hypokalemia, and hypomagnesemia. The purpose of this article was to bring an acute awareness of refeeding syndrome to the critical care nurse. The recognition, pathogenesis, clinical manifestations, potential life threatening complications, and treatment are presented.

Improving blood sugar control during critical illness: a cohort study

PURPOSE

The aim of this study is to compare blood sugar control and safety profile of nurse-titrated and medically ordered glucose-insulin regimens.

MATERIALS AND METHODS

We conducted a retrospective cohort study in a 9-bedded regional intensive care unit (ICU) in Queensland, Australia. Seventy critically ill patients requiring one-on-one nursing and intravenous insulin were included. In the nursing group, the ICU nurse decided initial and ongoing insulin infusion rates and glucose measurement frequency. The medical group had a traditional insulin sliding scale prescription.

RESULTS

Thirty-seven patients in the nursing group had 1949 glucose measurements. Thirty-three patients in the medical group had 2118 measurements. Mean blood sugar levels (+/-SD) were 8.33 +/- 2.34 and 8.78 +/- 2.74 in nursing and medical groups (P < .001). Eighteen percent of glucose readings were greater than 10 mmol/L in the nursing group compared with 27% in the medical group (P = .038). The incidence of hypoglycemia (<2.2 mmol/L) was similar in the 2 groups.

CONCLUSIONS

In a regional ICU, nurse-titrated glycemic control is safe, effective, and results in high compliance with a glucose target range.

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.

Glycemic penalty index for adequately assessing and comparing different blood glucose control algorithms

Introduction

Blood glucose (BG) control performed by intensive care unit (ICU) nurses is becoming standard practice for critically ill patients. New (semi-automated) 'BG control' algorithms (or 'insulin titration' algorithms) are under development, but these require stringent validation before they can replace the currently used algorithms. Existing methods for objectively comparing different insulin titration algorithms show weaknesses. In the current study, a new approach for appropriately assessing the adequacy of different algorithms is proposed.

Methods

Two ICU patient populations (with different baseline characteristics) were studied, both treated with a similar 'nurse-driven' insulin titration algorithm targeting BG levels of 80 to 110 mg/dl. A new method for objectively evaluating BG deviations from normoglycemia was founded on a smooth penalty function. Next, the performance of this new evaluation tool was compared with the current standard assessment methods, on an individual as well as a population basis. Finally, the impact of four selected parameters (the average BG sampling frequency, the duration of algorithm application, the severity of disease, and the type of illness) on the performance of an insulin titration algorithm was determined by multiple regression analysis.

Results

The glycemic penalty index (GPI) was proposed as a tool for assessing the overall glycemic control behavior in ICU patients. The GPI of a patient is the average of all penalties that are individually assigned to each measured BG value based on the optimized smooth penalty function. The computation of this index returns a number between 0 (no penalty) and 100 (the highest penalty). For some patients, the assessment of the BG control behavior using the traditional standard evaluation methods was different from the evaluation with GPI. Two parameters were found to have a significant impact on GPI: the BG sampling frequency and the duration of algorithm application. A higher BG sampling frequency and a longer algorithm application duration resulted in an apparently better performance, as indicated by a lower GPI.

Conclusion

The GPI is an alternative method for evaluating the performance of BG control algorithms. The blood glucose sampling frequency and the duration of algorithm application should be similar when comparing algorithms.

Blood glucose control in critical care patients - a review of the literature

The role of hyperglycaemia in critical illness, and its corresponding treatment, has been an area of controversy, fuelled by conflicting research findings. The aims of this study were to critically evaluate the literature and present an historical review of the sequence of published papers relating to blood glucose control in critical care. Their subsequent impact together with the implications for patient care is discussed. This article is based on a systematic review of papers relating to glycaemic control in critical care patients. The review was conducted using the MedLine, CINAHL and EMBASE databases using key search terms (details of the search terms can be found after the conclusion of the paper) for the period 1950-2006. The searches resulted in 4863 papers being screened for relevance to the historic progression of glycaemic management in critical care patients, by title and then abstract. Of these, 209 were accessed, and their reference lists were snowballed for further papers. Papers that were repeatedly quoted throughout the literature and were therefore considered important in the historical development of accepted critical care practice were finally subjected to rigorous appraisal. These totalled 91 papers and included 18 randomized controlled trials, an additional 28 research papers, 25 editorials and 20 reviews. This critical evaluation of published work indicates that the evidence for the benefit of this therapy may not be as compelling as previously indicated, and its widespread use may have been premature. From a nursing perspective, this demonstrates the importance of maintaining a questioning attitude to new therapies and reviewing best practice in the light of evolving evidence.

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.

Intensive insulin therapy for acute hyperglycemia

There is growing evidence that control of hyperglycemia in the critically ill patient improves outcome. Normalizing blood glucose levels decreases the risk of developing sepsis, end-organ damage, and hospital mortality. Critical care clinicians must be familiar with current and benchmark research supporting control of hyperglycemia and use this knowledge to ensure appropriate application of evidence-based practice for decreasing or preventing complications in the critically ill patient. This article describes the effects of hyperglycemia and discusses the evidence supporting tight glycemic control in such patients. The necessary steps to implement an intensive insulin therapy protocol for control of acute hyperglycemia are detailed.

Poor glycemic control is associated with increased mortality in critically ill trauma patients

Glycemic control improves outcome in cardiac surgical patients and after myocardial infarction or stroke. Hyperglycemic predicts poor outcome in trauma, but currently no data exist on the effect of glycemic control in critically ill trauma patients. In our intensive care unit (ICU), we use a subcutaneous sliding scale insulin protocol to achieve glucose levels <140 mg/dL. We hypothesized that aggressive glycemic control would be associated with improved outcome in critically ill trauma patients. At our urban Level 1 trauma center, a retrospective study was conducted of all injured patients admitted to the surgical ICU >48 hours during a 6-month period. Data were collected for mechanism of injury, age, diabetic history, Injury Severity Score (ISS), and APACHE II score. All blood glucose levels, by laboratory serum measurement or by point-of-care finger stick, were collected for the entire ICU stay. Outcome data (mortality, ICU and hospital length of stay, ventilator days, and complications) were collected and analyzed. Patients were stratified by their preinjury diabetic history and their level of glucose control (controlled <140 mg/dL vs non-controlled > or =141 mg/dL) and these groups were compared. During the study period, 103 trauma patients were admitted to the surgical ICU >48 hours. Ninety (87.4%) were nondiabetic. Most (83.5%) sustained blunt trauma. The average age was 50 +/- 21 years, the average ISS was 22 +/- 12, and the average APACHE II was 16 +/- 9. The average glucose for the population was 128 +/-25 mg/dL. Glycemic control was not attained in 27 (26.2%) patients; 19 (70.4%) of these were nondiabetic. There were no differences in ISS or APACHE II for controlled versus non-controlled patients. However, non-controlled patients were older. Mortality was 9.09 per cent for the controlled group and was 22.22 per cent for the non-controlled group. Diabetic patients were older and less severely injured than nondiabetics. For nondiabetic patients, mortality was 9.86 per cent in controlled patients and 31.58 per cent in non-controlled patients (P < 0.05). Also, urinary tract infections were more prevalent and complication rates overall were higher in nondiabetic patients with noncontrolled glucose levels. Nonsurvivors had higher average glucose than survivors (P < 0.03). Poor glycemic control is associated with increased morbidity and mortality in critically ill trauma patients; this is more pronounced in nondiabetic patients. Age may be a factor in these findings. Subcutaneous sliding scale insulin alone may be inadequate to maintain glycemic control in older critically ill injured patients and in patients with greater physiologic insult. Prospective assessment is needed to further clarify the benefits of aggressive glycemic control, to assess the optimal mode of insulin delivery, and to better define therapeutic goals in critically ill, injured patients.

Accuracy of roche accu-chek inform whole blood capillary, arterial, and venous glucose values in patients receiving intensive intravenous insulin therapy after cardiac surgery

Intravenous insulin protocols are increasingly common in the intensive care unit to maintain normoglycemia. Little is known about the accuracy of point-of-care glucometers for measuring glucose in this patient population or the impact of sample source (capillary, arterial, or venous whole blood) on the accuracy of glucometer results. We compared capillary, arterial, and venous whole blood glucose values with laboratory plasma glucose values in 20 patients after cardiac surgery. All 4 samples (capillary, arterial, and venous whole blood and laboratory plasma glucose) were analyzed hourly for the first 5 hours during intravenous insulin therapy in the intensive care unit. There were no significant differences between median capillary whole blood (149 mg/dL [8.3 mmol/L]) and laboratory plasma (151 mg/dL [8.4 mmol/L]) glucose levels. The median arterial (161 mg/dL [8.9 mmol/L]) and venous (162 mg/dL [9.0 mmol/L]) whole blood glucose levels were significantly higher than the median laboratory plasma glucose level. Capillary whole blood glucose levels correlate most closely with laboratory plasma glucose levels in patients receiving intensive intravenous insulin therapy after cardiac surgery.

Working to improve care of hospital hyperglycemia through statewide collaboration: the Georgia Hospital Association Diabetes Special Interest Group

OBJECTIVE

To review the efforts of the Georgia Hospital Association Diabetes Special Interest Group (DSIG) to develop and disseminate sample clinical guidelines on management of inpatient hyperglycemia.

METHODS

Beginning in February 2003, a consortium of physicians and allied health professionals from throughout the state of Georgia began meeting on a frequent basis to formulate a plan to enhance the care of hospitalized patients with hyperglycemia. The immediate goals of the DSIG were the identification and organization of interested stakeholders, the development of consensus sample clinical guidelines, and the dissemination of information.

RESULTS

Since its inception, the DSIG has accomplished the following: development of 7 consensus sample clinical guidelines, construction of a Web site that posts these clinical guidelines and other useful related information and educational materials, and sponsorship of workshops throughout the state of Georgia.

CONCLUSION

As the importance of glucose control in the hospital setting has become increasingly recognized, institutions must find ways of applying results of clinical trials to "real-world" hospital environments. The DSIG is an example of a successful collaboration that could serve as a model for other state hospital organizations that wish to develop programs to enhance the care of inpatients with hyperglycemia.

Intensive insulin therapy in critical care: a review of 12 protocols

OBJECTIVE

To review performance characteristics of 12 insulin infusion protocols.

RESEARCH DESIGN AND METHODS

We systematically identify and compare 12 protocols and then apply the protocols to generate insulin recommendations in the management of a patient with hyperglycemia. The main focus involves a comparison of insulin doses and patterns of insulin administration.

RESULTS

There is great variability in protocols. Areas of variation include differences in initiation and titration of insulin, use of bolus dosing, requirements for calculation in adjustment of the insulin infusion, and method of insulin protocol adjustments. Insulin recommendations for a sample patient are calculated to highlight differences between protocols, including the patterns and ranges of insulin dose recommended (range 27-115 units [mean +/- SD 66.7 +/- 27.9]), amount recommended for glucose readings >200 mg/dl, and adjustments nearing target glucose.

CONCLUSIONS

The lack of consensus in the delivery of intravenous insulin infusions is reflected in the wide variability of practice noted in this survey. This mandates close attention to the choice of a protocol. One protocol may not suffice for all patients.

Implementing an intravenous insulin infusion protocol in the intensive care unit

PURPOSE

The implementation of three different insulin protocols in intensive care unit (ICU) settings in two community hospitals and one academic hospital is described.

SUMMARY

Each institution possessed a commitment to improve the existing insulin protocols in order to achieve tighter glycemic control for ICU patients. Studies have shown that the maintenance of tight glycemic control provides improved patient outcomes. Obstacles to implementation of the insulin protocols at the institutions were increased staff workload, difficulties in interpreting algorithms, and lack of perceived benefit. In comparing details of the insulin protocols at the academic and community hospitals, it was found that differences were influenced by the type of institution. The differences among the institutions in the implementation of the protocols included the initial physician response to the protocol, the details of each protocol, nursing staff autonomy, and the involvement of the nursing staff in early protocol development. All three institutions had a dedicated pharmacist in the ICU who committed time toward insulin protocol implementation. For an increased likelihood of successful insulin protocol implementation, a full-time dedicated ICU pharmacist should be assigned to participate on multidisciplinary rounds, provide nursing support and education, and collect process measures to monitor and improve the protocol.

CONCLUSION

The i.v. insulin infusion protocols developed and implemented in the ICUs at three institutions successfully achieved acceptance and compliance by physicians and nurses. The factors attributed to the success were multidisciplinary involvement, the continuous education of nursing staff, the vigilant involvement of a pharmacist, and flexibility in revising the protocol.

A review of the use of insulin protocols to maintain normoglycaemia in high dependency patients

AIM

This paper critically examines the evidence base for and issues involved in the introduction of an insulin protocol to maintain normoglycaemia in patients within a medical/surgical high dependency ward.

BACKGROUND

A growing body of evidence has linked hyperglycaemia to worsened clinical outcomes. This has led to intravenous insulin protocols becoming a new standard of care in intensive care units. However, the use and benefits of insulin protocols within high dependency units have not yet been addressed in the literature.

METHODS

The literature was examined for the 10-year period up to January 2005. The databases searched were MEDLINE, OVID, CINHAL, the British Nursing Index, the EBSCO collection, the COCHRANE library, the Department of Health, and guidelines within the Scottish Intercollegiate Guidelines Network and National Institute for Clinical Excellence using the key words insulin, protocol, hyperglycaemia, critical care, intensive care and high dependency.

RESULTS

The literature reports that both medical and surgical intensive care patients treated with intravenous insulin protocols to maintain normoglycaemia experienced significantly reduced mortality and morbidity. Resulting hypoglycaemic episodes were limited with no incidence of patient deterioration. A review of published intravenous insulin protocols used in intensive care settings revealed their safe and effective use in nurse to patient ratios similar to those present in high dependency units.

CONCLUSIONS

In the light of this evidence, it would seem safe and ethically correct to enable high dependency patients to benefit from this cheap intervention. An insulin protocol tailored for the glycaemic control of high dependency patients has been suggested, although it may have to be commenced in conjunction with other fluid and nutrition protocols to safeguard the risk of hypoglycaemic events. Further research into the safety and benefit of insulin protocols in high dependency populations is required.

RELEVANCE TO CLINICAL PRACTICE

The stress of critical illness often leads to hyperglycaemia, which is linked to worsened clinical outcomes. Both medical and surgical intensive care patients treated with intravenous insulin protocols to maintain normoglycaemia experienced significantly reduced mortality and morbidity. This paper identifies that, to date, no research into the benefits of glycaemic control in high dependency populations has been published. The case for the introduction of insulin protocols into high dependency units is therefore examined and an insulin protocol suggested.

Computer-based insulin infusion protocol improves glycemia control over manual protocol

OBJECTIVE

Hyperglycemia worsens clinical outcomes in critically ill patients. Precise glycemia control using intravenous insulin improves outcomes. To determine if we could improve glycemia control over a previous paper-based, manual protocol, authors implemented, in a surgical intensive care unit (SICU), an intravenous insulin protocol integrated into a care provider order entry (CPOE) system.

DESIGN

Retrospective before-after study of consecutive adult patients admitted to a SICU during pre (manual protocol, 32 days) and post (computer-based protocol, 49 days) periods.

MEASUREMENTS

Percentage of glucose readings in ideal range of 70-109 mg/dl, and minutes spent in ideal range of control during the first 5 days of SICU stay.

RESULTS

The computer-based protocol reduced time from first glucose measurement to initiation of insulin protocol, improved the percentage of all SICU glucose readings in the ideal range, and improved control in patients on IV insulin for > or =24 hours. Hypoglycemia (<40 mg/dl) was rare in both groups.

CONCLUSION

The CPOE-based intravenous insulin protocol improved glycemia control in SICU patients compared to a previous manual protocol, and reduced time to insulin therapy initiation. Integrating a computer-based insulin protocol into a CPOE system achieved efficient, safe, and effective glycemia control in SICU patients.

A practical approach to hyperglycemia management in the intensive care unit: evaluation of an intensive insulin infusion protocol

STUDY OBJECTIVES

To evaluate the effectiveness and safety of maintaining a target blood glucose concentration of 91-130 mg/dl with a standardized, nurse-managed, intensive insulin infusion protocol outside a study setting, and to determine if a statistically significant favorable effect on morbidity and mortality was achieved.

DESIGN

Retrospective, observational, chart review.

SETTING

Medical and surgical intensive care units (ICUs) in a community teaching hospital.

PATIENTS

One hundred forty-three adult patients who received insulin infusions managed at the discretion of the physician over a 1-year period before initiation of the protocol (control group), and 70 patients who received insulin infusions over a 6-month period with infusion dosages titrated by using the protocol (protocol group).

MEASUREMENTS AND MAIN RESULTS

Episodes of hypoglycemia, time within target range, mean blood glucose concentration, frequency of measurement, length of ICU stay, duration of mechanical ventilation, and overall mortality were collected. Hypoglycemic episodes were not significantly different between the groups. Blood glucose concentrations were within target range in 34% of all measurements in the protocol group compared with 23% in the control group (p<0.001, relative risk [RR] 1.48, 95% confidence interval [CI] 1.38-1.58). Once target range was reached on one measurement, 43% of concentrations remained in target range in the protocol group compared with 29% in the control group (p<0.001, RR 1.47, 95% CI 1.38-1.56). Frequency of measurements was higher in the protocol group versus control group (p=0.01); however, clinical difference was minimal. Protocol group had lower overall mortality rate (27% [19/70] vs 32% [46/143], p=0.45), reduced mean ICU length of stay (16.7 +/- 10.6 vs 18.4 +/- 16.0 days, p=0.37), and less mechanical ventilation time (16.5 +/- 9.7 vs 17.0 +/- 15.0 days, p=0.79).

CONCLUSION

The nurse-managed insulin infusion protocol improved glycemic control with minimal hypoglycemic episodes compared with baseline practice. A trend toward decreased mortality, ICU length of stay, sand days of mechanical ventilation was observed. When compared with other published protocols, our insulin protocol displays comparable effectiveness with the use of less-frequent blood glucose measurements.

Mandatory protocol for treating adult patients with diabetic ketoacidosis decreases intensive care unit and hospital lengths of stay: results of a nonrandomized trial

OBJECTIVE

To determine the effect of a mandatory protocol for treating diabetic ketoacidosis.

DESIGN

Chart review of patients treated before and after protocol implementation.

SETTING

University-affiliated U.S. public teaching hospital.

PATIENTS

A total of 241 consecutive nonpregnant patients >18 yrs old admitted to a medical intensive care unit for diabetic ketoacidosis between January 2000 and January 2005.

INTERVENTION

Implementation of a mandatory treatment protocol in May 2003.

MEASUREMENTS

Intensive care unit and hospital lengths of stay, time to correction of anion gap and ketone clearance, and hypoglycemic episodes.

RESULTS

Before protocol implementation, the mean +/- sd intensive care unit and hospital lengths of stay were 44 +/- 28 hrs and 91 +/- 73 hrs, respectively. After implementation, intensive care unit and hospital lengths of stay decreased 23% and 30%, to 34 +/- 18 hrs and 64 +/- 41 hrs, respectively (both p < .007). Time to anion gap closure and ketone clearance also decreased (both p < .05). No difference in the number of hypoglycemic episodes was observed.

CONCLUSION

Implementing a mandatory protocol for treating adult patients with diabetic ketoacidosis decreases intensive care and hospital lengths of stay and time to anion gap closure and ketone clearance, without increasing the rate of hypoglycemia.

Glycaemic control in critically ill patients with cardiovascular disease

PURPOSE OF REVIEW

The role of hyperglycaemia in the pathogenesis of myocardial damage during cardiac surgery or patients with acute coronary syndromes has been the subject of increasing interest over the past few years. Several further trials and meta-analyses investigating the role of insulin treatment, either aimed at tight control of blood glucose concentration or as part of a regimen including glucose and potassium, have been reported recently and are the subject of this review.

RECENT FINDINGS

Good control of blood glucose has been demonstrated to improve outcomes for diabetic patients undergoing cardiac surgery and following acute myocardial infarction. In surgical intensive care patients, tight glucose control improved mortality--a finding that is awaiting confirmation in multicentre studies. The use of glucose-insulin-potassium regimens does not improve outcomes in patients with acute myocardial infarction who have undergone reperfusion therapy, but may be beneficial during cardiac surgery.

SUMMARY

Tight control of blood glucose has been shown to be beneficial in several patient groups. The optimal target glucose concentration and glucose and insulin regimens remain to be confirmed or determined in each clinical situation.