Hypoglycemia with intensive insulin therapy in critically ill patients: Predisposing factors and association with mortality*:

Continuous insulin administration via complex central venous catheter infusion tubing is another risk factor for blood glucose imbalance. A retrospective study

Background

We assessed the potential impact of infusion tubing on blood glucose imbalance in ICU patients given intensive insulin therapy (IIT). We compared the incidence of blood glucose imbalance in patients equipped, in a nonrandomized fashion, with either conventional tubing or with a multiport infusion device.

Methods

We retrospectively analyzed the nursing files of 35 patients given IIT through the distal line of a double-lumen central venous catheter. A total of 1389 hours of IIT were analyzed for occurrence of hypoglycemic events [defined as arterial blood glucose below 90 mg/dL requiring discontinuation of insulin].

Results

Twenty-one hypoglycemic events were noted (density of incidence 15 for 1000 hours of ITT). In 17 of these 21 events (81%), medication had been administered during the previous hour through the line connected to the distal lumen of the catheter. Conventional tubing use was associated with a higher density of incidence of hypoglycemic events than multiport infusion device use (23 vs. 2 for 1,000 hours of IIT; rate ratio = 11.5; 95% confidence interval, 2.71–48.8; p < 0.001).

Conclusions

The administration of on-demand medication through tubing carrying other medications can lead to the delivery of significant amounts of unscheduled products. Hypoglycaemia observed during IIT could be related to this phenomenon. The use of a multiport infusion device with a limited dead volume could limit hypoglycemia in patients on IIT.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): hyperglycemia and diabetes mellitus]

Hyperglycemia is one of the main metabolic disturbances in critically-ill patients and is associated with increased morbidity and mortality. Consequently, blood glucose levels must be safely and effectively controlled, that is, maintained within a normal range, avoiding hypoglycemia on the one hand and elevated glucose concentrations on the other. To accomplish this aim, insulin is often required, avoiding protocols designed to achieve tight glycemic control. To prevent hyperglycemia and its associated complications, energy intake should be adjusted to patients' requirements, avoiding overnutrition and excessive glucose intake. Protein intake should be adjusted to the degree of metabolic stress. Whenever patients require artificial feeding, the enteral route, if not contraindicated, should be used since parenteral nutrition is associated with a higher frequency of hyperglycemia and greater insulin requirements. Enteral nutrition should be administered early, preferably within the first 24 hours of admission to the intensive care unit, after hemodynamic stabilization. Specific diets for hyperglycemia, containing low glycemic index carbohydrates and fibre and enriched with monounsaturated fatty acids, can achieve good glycemic control with lower insulin requirements.

Duration of time on intensive insulin therapy predicts severe hypoglycemia in the surgically critically ill population

BACKGROUND

Hypoglycemia has emerged as a barrier to the practice of intensive insulin therapy. Current literature suggests that hypoglycemia occurs at variable rates and has different effects on outcomes in surgical and medical populations. We sought to determine the incidence, independent predictors, and effect on outcome of severe hypoglycemia (≤ 40 mg/dl) in a surgical population.

METHODS

A retrospective analysis was performed on all critically ill surgical patients treated with IIT from October 2004 to February 2007. Euglycemia (goal 80-110 mg/dl) was maintained using automated computerized titration of an insulin infusion. The primary outcome of interest was any episode of severe hypoglycemia (≤ 40 mg/dl). Multivariate logistic regression was used to determine the independent predictors of developing severe hypoglycemia.

RESULTS

A total of 60,298 data entries (1,118 patients) for glucose were analyzed. There were 64 severe hypoglycemic episodes in 52 patients (4.6% of the patients). There was a significant increase in deaths among patients who experienced at least one episode of hypoglycemia when compared with those who did not (26.9% vs. 15.3%, P = 0.03). Logistic regression revealed that the time spent on the protocol was the best predictor of developing a hypoglycemic event when controlling for other known risk factors of hypoglycemia.

CONCLUSIONS

Intensive insulin therapy can be implemented with a low percentage of patients (4.6%) experiencing severe hypoglycemia. Mortality rate was higher for patients experiencing hypoglycemia. The duration of the time spent on the protocol was the best predictor of hypoglycemia, suggesting that hypoglycemia is a mathematic probability of prolonged illness, not a reflection of illness severity or demographic features.

Insulin therapy for the management of hyperglycemia in hospitalized patients

It has long been established that hyperglycemia with or without a prior diagnosis of diabetes increases both mortality and disease-specific morbidity in hospitalized patients and that goal-directed insulin therapy can improve outcomes. This article reviews the pathophysiology of hyperglycemia during illness, the mechanisms for increased complications and mortality due to hyperglycemia and hypoglycemia, and beneficial mechanistic effects of insulin therapy and provides updated recommendations for the inpatient management of diabetes in the critical care setting and in the general medicine and surgical settings.

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.

Glycemic targets and approaches to management of the patient with critical illness

Hyperglycemia during critical illness is associated with adverse outcome. The proof-of-concept Leuven studies assessed causality, and revealed that targeting strict normoglycemia (80-110 mg/dL) with insulin improved outcome compared with tolerating hyperglycemia to the renal threshold (215 mg/dL). A large multicenter trial (NICE-SUGAR [Normoglycaemia in Intensive Care Evaluation and Survival Using Glucose Algorithm Regulation]) found an intermediate blood glucose target (140-180 mg/dL) safer than targeting normoglycemia. Differences in design and in execution of glycemic control at the bedside may have contributed to these results. In NICE-SUGAR (Normoglycaemia in Intensive Care Evaluation and Survival Using Glucose Algorithm Regulation), the blood-glucose target range in the control group was lower, there were problems to reach and maintain normoglycemia in the intervention group, and inaccurate handheld blood glucose meters and variable blood sampling sites were allowed. Inaccurate tools led to insulin-dosing errors with consequently (undetected) hypoglycemia and unacceptable blood glucose variability. Also, the studies were done superimposed upon different nutritional strategies. Thus, such differences do not allow simple, evidence-based recommendations for daily practice, but an intermediate blood glucose target may be preferable while awaiting better tools to facilitate safely reaching normoglycemia.

Association of hyperglycemia, glucocorticoids, and insulin use with morbidity and mortality in the pediatric intensive care unit

BACKGROUND

Studies of pediatric intensive care unit (PICU) patients have shown a significant association of morbidity and mortality with hyperglycemia. We retrospectively evaluated the degree of hyperglycemia as well as its correlation with glucocorticoid and insulin use and assessed its association with hospital length of stay (LOS) and mortality. This study preceded the initiation of a standard glycemic control protocol.

METHODS

We examined medical records at Kosair Children's Hospital for all PICU admissions from 2008 of patients without diabetes mellitus. Critical illness hyperglycemia (CIH) was defined by having three or more peak glucose values greater than thresholds of 110, 140, 180, and 200 mg/dl. These patients were evaluated for glucocorticoid, insulin use, and outcome measures.

RESULTS

We evaluated the eligible 1173 admissions, where 10.5% of these patients reached the highest threshold (200 mg/dl) of CIH. Glucocorticoids were used in 43% of these patients, with dexamethasone being the most common (58%). There was a significant correlation between glucocorticoids and higher peak glucose values, where 81% of the patients who were above the 200 mg/dl cutoff level were treated with glucocorticoids. Only 36.8% in that group were also treated with insulin. Patients at the 200 mg/dl cutoff had the highest median PICU and total hospital length of stays (4 and 10 days, respectfully). Mortality was associated with increasing glucose levels, reaching 18.7% among patients above the 200 mg/dl cutoff.

CONCLUSION

Hyperglycemia was prevalent in the PICU and was associated with increased morbidity, as characterized by increased LOS and increased mortality. Glucocorticoid use was prevalent among patients exhibiting hyperglycemia. Insulin use was uncommon.

Efficacy and safety of intensive insulin therapy for critically ill neurologic patients: a meta-analysis

BACKGROUND

Whether intensive insulin therapy (IIT) may improve clinical outcomes for patients admitted to intensive care units, especially critically ill neurologic patients, is still debated. In the present study, we performed a meta-analysis of literature comparing the efficacy and safety of IIT and conventional insulin therapy (CIT) for critically ill neurologic patients in terms of mortality, infection rate, neurologic outcome, and hypoglycemia.

METHODS

We searched for published reports of studies of randomized control trials (up to March 10, 2011) of patients admitted to neurologic intensive care units and investigated an IIT (target of blood glucose control <120 mg/dL) with a control of CIT. Data were abstracted by a standardized protocol.

RESULTS

We retrieved reports of five studies involving 924 patients. The risk of mortality, infection rate, and neurologic outcome did not differ with IIT or CIT. However, the incidence of hypoglycemic episodes was significantly higher with IIT than CIT (78.8% vs. 48.9%), with a relative risk of 2.62 (95% confidence interval [CI]: 1.07-6.43; p < 0.04).

CONCLUSIONS

As compared with CIT, IIT may not benefit critically ill neurologic patients in terms of mortality, infection rate, or neurologic outcome and in fact may be associated with increased hypoglycemic complications. Therefore, IIT cannot be recommended over conventional control for critical neurologic disease, but further study is warranted.

Mild hypoglycemia is strongly associated with increased intensive care unit length of stay

Background

Hypoglycemia is associated with increased mortality in critically ill patients. The impact of hypoglycemia on resource utilization has not been investigated. The objective of this investigation was to evaluate the association of hypoglycemia, defined as a blood glucose concentration (BG) < 70 mg/dL, and intensive care unit (ICU) length of stay (LOS) in three different cohorts of critically ill patients.

Methods

This is a retrospective investigation of prospectively collected data, including patients from two large observational cohorts: 3,263 patients admitted to Stamford Hospital (ST) and 2,063 patients admitted to three institutions in The Netherlands (NL) as well as 914 patients from the GLUCONTROL trial (GL), a multicenter prospective randomized controlled trial of intensive insulin therapy.

Results

Patients with hypoglycemia were more likely to be diabetic, had higher APACHE II scores, and higher mortality than did patients without hypoglycemia. Patients with hypoglycemia had longer ICU LOS (median [interquartile range]) in ST (3.0 [1.4-7.1] vs. 1.2 [0.8-2.3] days, P < 0.0001), NL (5.2 [2.6-10.3] vs. 2.0 [1.3-3.2] days, P < 0.0001), and GL (9 [5-17] vs. 5 [3-9] days, P < 0.0001). For the entire cohort of 6,240 patients ICU LOS was 1.8 (1.0-3.3) days for those without hypoglycemia and 3.0 (1.5-6.7) days for those with a single episode of hypoglycemia (P < 0.0001). This was a consistent finding even when patients were stratified by severity of illness or survivor status. There was a strong positive correlation between the number of episodes of hypoglycemia and ICU LOS among all three cohorts.

Conclusions

This multicenter international investigation demonstrated that hypoglycemia was consistently associated with significantly higher ICU LOS in heterogeneous cohorts of critically ill patients, independently of severity of illness and survivor status. More effective methods to prevent hypoglycemia in these patients may positively impact their cost of care.

Hypoglycemia revisited in the acute care setting

Hypoglycemia is a common finding in both daily clinical practice and acute care settings. The causes of severe hypoglycemia (SH) are multi-factorial and the major etiologies are iatrogenic, infectious diseases with sepsis and tumor or autoimmune diseases. With the advent of aggressive lowering of HbA1c values to achieve optimal glycemic control, patients are at increased risk of hypoglycemic episodes. Iatrogenic hypoglycemia can cause recurrent morbidity, sometime irreversible neurologic complications and even death, and further preclude maintenance of euglycemia over a lifetime of diabetes. Recent studies have shown that hypoglycemia is associated with adverse outcomes in many acute illnesses. In addition, hypoglycemia is associated with increased mortality among elderly and non-diabetic hospitalized patients. Clinicians should have high clinical suspicion of subtle symptoms of hypoglycemia and provide prompt treatment. Clinicians should know that hypoglycemia is associated with considerable adverse outcomes in many acute critical illnesses. In order to reduce hypoglycemia-associated morbidity and mortality, timely health education programs and close monitoring should be applied to those diabetic patients presenting to the Emergency Department with SH. ED disposition strategies should be further validated and justified to achieve balance between the benefits of euglycemia and the risks of SH. We discuss relevant issues regarding hypoglycemia in emergency and critical care settings.

The place for glycemic control in the surgical patient

BACKGROUND

Hyperglycemia is common in surgical patients and is associated with adverse outcomes. Conflicting data exist regarding the best method and the value of glycemic control in various patient populations. The contributions to hyperglycemia and the components of its control are complex and overlapping and likely contribute to the documented variation in outcomes. We provide an overview of the physiologic contributors to hyperglycemia and its control, review the differences in the major randomized trial results, and summarize the data regarding glycemic control in surgical patients.

METHODS

Major reviews of the pathophysiology of hyperglycemia in surgical patients, large randomized trials in critically ill and peri-operative populations, and meta-analyses were reviewed. Summations are provided for the critically ill population and for the peri-operative group.

RESULTS

A substantial physiologic rationale exists for the control of hyperglycemia in surgical patients during critical illness and in the peri-operative period. Randomized, controlled studies are limited predominately to critically ill populations. The data support controlling hyperglycemia to a serum glucose concentration <200 mg/dL, but the absolute target range remains controversial and studied inadequately. The data indicate the benefit of tight glycemic control using insulin to achieve a target of 80-110 mg/dL (intensive insulin therapy [IIT]) vs. a liberal target of 180-200 mg/dL in critically ill surgical patients, although hypoglycemia is more common with IIT. Inadequate studies are available in the peri-operative period to draw conclusions about non-critically ill surgical patients, but the weight of the data suggests control to < 200 mg/dL likely is beneficial.

CONCLUSIONS

Surgical patients benefit from maintaining serum glucose concentrations <200 mg/dL. Intensive insulin therapy (80-110 mg/dL), which appears beneficial in critically ill surgical patients but requires frequent measurement of glucose to avoid hypoglycemia. Further studies are needed to determine the appropriate target range and the influence of nutritional provision and other factors on outcome.

Provision of balanced nutrition protects against hypoglycemia in the critically ill surgical patient

BACKGROUND

Intensive insulin therapy lowers blood glucose and improves outcomes but increases the risk of hypoglycemia. Typically, insulin protocols require a dextrose solution to prevent hypoglycemia. The authors hypothesized that the provision of balanced nutrition (enteral nutrition [EN] or parenteral nutrition [PN]) would be more protective against hypoglycemia (≤50 mg/dL) than carbohydrate alone.

METHODS

A retrospective analysis was performed of patients treated with intensive insulin therapy and surviving ≥24 hours. The computer-based insulin protocol requires infusion of D10W at 30 mL/h if EN or PN is not provided. Nutrition provision was assessed in 2-hour increments, comparing periods of blood glucose control with and without balanced nutrition. The risk of hypoglycemia for each blood glucose measurement was estimated by multivariable regression.

RESULTS

In total, 66,592 glucose measurements were collected on 1392 patients. Hypoglycemic events occurred in 5.8/1000 glucose tests after 2 hours without balanced nutrition compared to 2.2/1000 tests when balanced nutrition was given in the preceding 2 hours. In multivariable regression models, balanced nutrition was the strongest protective factor against hypoglycemia. Patients who did not receive balanced nutrition in the preceding 2 hours had a 3 times increase in the odds of a hypoglycemic event at their next glucose check (odds ratio = 3.6, P < .001). Providing carbohydrate alone was not protective.

CONCLUSIONS

Balanced nutrition is associated with reduced risk of hypoglycemia. These results suggest that balanced nutrition should be given when insulin therapy is initiated. Future studies should evaluate the efficacy of EN vs PN in preventing hypoglycemia.

Which variables are associated with blood glucose levels outside the target range in surgical critically ill patients? A retrospective observational study

BACKGROUND

The aim of the present study is to determine the variables affecting blood glucose concentrations outside the target range of 80 and 150 mg/dl in critically ill surgical patients.

METHODS

All critically ill surgical patients admitted to a university ICU, from 01/2007 to 12/2008, were surveyed daily using computer assistance with respect to minimal and maximal daily blood glucose concentrations, application of insulin and demographic/clinical variables. Multiple logistic regression for clustered data with backward elimination was performed to identify variables strongly associated with blood glucose concentrations < 80 mg/dl or ≥ 150 mg/dl in 804 patients with an ICU stay > 72 hours.

RESULTS

Application of insulin (odds ratio (OR) 2.1, with corresponding 95% confidence interval (CI) 1.7; 2.6), noradrenaline (OR 1.4, 95% CI 1.2 - 1.8) or steroids (1.3, 1.003 - 1.7), and age (per year) (1.02, 1.01 - 1.03) were associated with an increased risk of blood glucose concentrations < 80 mg/dl. In analogy, application of insulin (OR 2.4, 95% CI 2.0 - 2.7), noradrenaline (1.4, 1.2 - 1.6) or steroids (1.4, 1.2 - 1.7), severe sepsis (1.2, 1.1 - 1.4), neurosurgery (OR 1.0) compared to abdominal, vascular and trauma surgery, and age (per year) (1.01, 1.01 - 1.02), were associated with an increased risk of blood glucose concentrations ≥ 150 mg/dl.

CONCLUSIONS

Critically ill surgical patients are at an increased risk for fluctuating blood glucose concentrations ranging < 80 mg/dl or ≥ 150 mg/dl in particular if they are of advanced age and require administration of insulin, noradrenaline, and/or steroids. Patients who underwent neurosurgery and/or presented with severe sepsis/shock are those in particular at risk for blood glucose concentrations ≥ 150 mg/dl.

Recognizing hypoglycemia in children through automated adverse-event detection

BACKGROUND

Automated adverse-event detection using triggers derived from the electronic health record (EHR) is an effective method of identifying adverse events, including hypoglycemia. However, the true occurrence of adverse events related to hypoglycemia in pediatric inpatients and the harm that results remain largely unknown.

OBJECTIVE

We describe the use of an automated adverse-event detection system to detect and categorize hypoglycemia-related adverse events in pediatric inpatients.

METHODS

A retrospective observational study of all hypoglycemia triggers generated by an EHR-driven surveillance system was conducted at a large urban children's hospital during a 1-year period. All hypoglycemia triggers were investigated to determine if they represented a true adverse event and if that event followed or deviated from the local standard of care. Clinical and demographic variables were analyzed to identify subpopulations at risk for hypoglycemia.

RESULTS

Of the 1254 hypoglycemia triggers produced, 198 were adverse events (positive predictive value: 15.8%). No hypoglycemic adverse events were identified via the hospital's voluntary incident-reporting system. The majority of hypoglycemia-related adverse events occurred in the NICU (n = 123 of 198 [62.1%]). A total of 154 (77.8%) of the 198 adverse events hospital-wide and 102 (83%) of the 123 adverse events in the NICU occurred in patients who were receiving insulin therapy.

CONCLUSIONS

Hypoglycemia is common in hospitalized children, particularly neonates and those who receive insulin. An EHR-driven automated adverse-event detection system was effective in identifying hypoglycemia in this population. Automated adverse-event detection holds great promise in augmenting the safety program of organizations who have adopted the EHR.

Increasing blood glucose variability heralds hypoglycemia in the critically ill

BACKGROUND

Control of hyperglycemia improves outcomes, but increases the risk of hypoglycemia. Recent evidence suggests that blood glucose variability (BGV) is more closely associated with mortality than either isolated or mean BG. We hypothesized that differences in BGV over time are associated with hypoglycemia and can be utilized to estimate risk of hypoglycemia (<50 mg/dL).

MATERIALS AND METHODS

Patients treated with intravenous insulin in the Surgical Intensive Care Unit of a tertiary care center formed the retrospective cohort. Exclusion criteria included death within 24 h of admission. We describe BGV in patients over time and its temporal relationship to hypoglycemic events. The risk of hypoglycemia for each BG measurement was estimated in a multivariable regression model. Predictors were measures of BGV, infusions of dextrose and vasopressors, patient demographics, illness severity, and BG measurements.

RESULTS

A total of 66,592 BG measurements were collected on 1392 patients. Hypoglycemia occurred in 154 patients (11.1%). Patient BGV fluctuated over time, and increased in the 24 h preceding a hypoglycemic event. In crude and adjusted analyses, higher BGV was positively associated with a hypoglycemia (OR 1.41, P < 0.001). Previous hypoglycemic events and time since previous BG measurement were also positively associated with hypoglycemic events. Severity of illness, vasopressor use, and diabetes were not independently associated with hypoglycemia.

CONCLUSIONS

BGV increases in the 24 h preceding hypoglycemia, and patients are at increased risk during periods of elevated BG variability. Prospective measurement of variability may identify periods of increased risk for hypoglycemia, and provide an opportunity to mitigate this risk.

Glucose management in the neurosurgical patient: are we yet any closer?

PURPOSE OF REVIEW

This review focuses on recent findings in perioperative management of blood glucose control using intensive insulin therapy in neurosurgical and neurocritical care and in other intensive care unit patients. We also aim to address practical issues and make recommendations that may contribute to the safe clinical application of intensive insulin therapy targeted to optimize blood glucose control in these patients.

RECENT FINDINGS

Intensive insulin therapy targeted to obtain tight blood glucose control induces a substantial increase in the number of hypoglycemic episodes and mortality rate. On the contrary, hyperglycemia--both isolated episodes and high mean glucose levels--is associated with worsened neurologic outcome and increased mortality.

SUMMARY

In neurosurgical and neurocritical care as well as other intensive care unit patients, both hypoglycemia and hyperglycemia have significant adverse effects. The optimal glucose level remains under debate but significant steps have evolved with the call for judicious control and elimination of the historical approach to glycemic management, which underestimated drawbacks associated with dysglycemia. The increased incidence of hypoglycemia and mortality as well as the impact of hyperglycemia on worsening neurologic function in patients with acute brain damage heightens the need for more clinical studies on perioperative glucose management in these patients.

Insulin therapy in critically ill patients

Hyperglycemia frequently occurs with acute medical illness, especially among patients with cardiovascular disease, and has been linked to increased morbidity and mortality in critically ill patients. Even patients who are normoglycemic can develop hyperglycemia in response to acute metabolic stress. An expanding body of literature describes the benefits of normalizing hyperglycemia with insulin therapy in hospitalized patients. As a result, both the American Diabetes Association and the American College of Endocrinology have developed guidelines for optimal control of hyperglycemia, specifically targeting critically ill, hospitalized patients. Conventional blood glucose values of 140–180 mg/dL are considered desirable and safely achievable in most patients. More aggressive control to <110 mg/dL remains controversial, but has shown benefits in certain patients, such as those in surgical intensive care. Intravenous infusion is often used for initial insulin administration, which can then be transitioned to subcutaneous insulin therapy in those patients who require continued insulin maintenance. This article reviews the data establishing the link between hyperglycemia and its risks of morbidity and mortality, and describes strategies that have proven effective in maintaining glycemic control in high-risk hospitalized patients.

Relationship between hypoglycemia and mortality in critically ill children

OBJECTIVES

To determine the prevalence of hypoglycemia in critically ill nondiabetic children and the association of hypoglycemia with mortality and worsening organ function in critically ill children.

DESIGN

Retrospective cohort study with matched-cohort analysis.

SETTING

Academic pediatric intensive care unit.

PATIENTS

A total of 899 nondiabetic patients <18 yrs old admitted to the pediatric intensive care unit for >1 day with at least one blood glucose measurement. Forty-two patients with a blood glucose level of <50 mg/dL (<2.8 mmol/L) were matched with 126 nonhypoglycemic patients.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Hypoglycemia, based on point-of-care blood glucose measurements, occurred in 2.2% (<40 mg/dL [<2.2 mmol/L]) to 7.5% (<60 mg/dL [<3.3 mmol/L]) of the patients. Hypoglycemia was more common in patients on mechanical ventilation and/or vasopressor support. Severity of hypoglycemia correlated with an increased mortality rate. The highest odds ratio of mortality was 4.49 (95% confidence interval [CI], 1.69-11.96; p < .01) at a blood glucose level of <40 mg/dL (<2.2 mmol/L). In the matched analysis, hypoglycemia was an independent risk factor for mortality. The unadjusted, covariate-adjusted, and propensity score-adjusted odds ratios of mortality were 3.69 (95% CI, 1.78-7.68; p < .01), 4.16 (95% CI, 1.53-11.32; p < .01), and 8.45 (95% CI, 1.75-40.86; p < .01), respectively. Hypoglycemia was associated with worsening organ function in the covariate-adjusted model (odds ratio, 2.37; 95% CI, 1.12-5.01; p = .02) but not in the unadjusted and propensity-score adjusted models.

CONCLUSIONS

Hypoglycemia is common in critically ill children. It is associated with increased mortality rates in critically ill nondiabetic children. Our data suggest that hypoglycemia is also associated with worsening organ function. Hypoglycemia may merely be a marker of severity of illness. Further investigations are needed to establish the mortality risk with hypoglycemia due to insulin compared to spontaneous hypoglycemia.

Increased hypoglycemia associated with renal failure during continuous intravenous insulin infusion and specialized nutritional support

OBJECTIVE

To evaluate glycemic control for critically ill, hyperglycemic trauma patients with renal failure who received concurrent intensive insulin therapy and continuous enteral nutrition (EN) or parenteral nutrition (PN).

METHODS

Adult trauma patients with renal failure who were given EN or PN concurrently with continuous graduated intravenous regular human insulin (RHI) infusion for at least 3 d were evaluated. Our conventional RHI algorithm was modified for those with renal failure by allowing greater changes in blood glucose (BG) concentrations before the infusion rate was escalated. BG concentration was determined every 1 to 2 h while receiving the insulin infusion. BG control was evaluated on the day before RHI infusion and for a maximum of 7 d while receiving RHI. Target BG during the RHI infusion was 70 to 149 mg/dL (3.9 to 8.3 mmol/L). Glycemic control and incidence of hypoglycemia for those with renal failure were compared with a historical cohort of critically ill, hyperglycemic trauma patients without renal failure given our conventional RHI algorithm.

RESULTS

Twenty-one patients with renal failure who received the modified RHI algorithm were evaluated and compared with 40 patients without renal failure given our conventional RHI algorithm. Average BG concentration was significantly greater for those with renal failure (133±14 mg/dL or 7.3±0.7 mmol/L) compared with those without renal failure (122±15 mg/dL or 6.8±0.8 mmol/L), respectively (P<0.01). Patients with renal failure showed worsened glycemic variability, with 16.1±3.3 h/d within the target BG range, 6.9±3.2 h/d above the target BG range, and 1.4±1.1 h/d below the target BG range compared with 19.6±4.7 h/d (P<0.001), 3.4±3.0 h/d (P<0.001), and 0.7±0.8 h/d (P<0.01) for those without renal failure, respectively. Moderate hypoglycemia (<60 mg/dL or<3.3 mmol/L) occurred in 76% of patients with renal failure compared with 35% without renal failure (P<0.005). Severe hypoglycemia (BG<40 mg/dL or<2.2 mmol/L) occurred in 29% of patients with renal failure compared with none of those without renal failure (P<0.001).

CONCLUSION

Despite receiving a modified RHI infusion, critically ill trauma patients with renal failure are at greater risk for developing hypoglycemia and have more glycemic variability than patients without renal failure.

International recommendations for glucose control in adult non diabetic critically ill patients

INTRODUCTION

The purpose of this research is to provide recommendations for the management of glycemic control in critically ill patients.

METHODS

Twenty-one experts issued recommendations related to one of the five pre-defined categories (glucose target, hypoglycemia, carbohydrate intake, monitoring of glycemia, algorithms and protocols), that were scored on a scale to obtain a strong or weak agreement. The GRADE (Grade of Recommendation, Assessment, Development and Evaluation) system was used, with a strong recommendation indicating a clear advantage for an intervention and a weak recommendation indicating that the balance between desirable and undesirable effects of an intervention is not clearly defined.

RESULTS

A glucose target of less than 10 mmol/L is strongly suggested, using intravenous insulin following a standard protocol, when spontaneous food intake is not possible. Definition of the severe hypoglycemia threshold of 2.2 mmol/L is recommended, regardless of the clinical signs. A general, unique amount of glucose (enteral/parenteral) to administer for any patient cannot be suggested. Glucose measurements should be performed on arterial rather than venous or capillary samples, using central lab or blood gas analysers rather than point-of-care glucose readers.

CONCLUSIONS

Thirty recommendations were obtained with a strong (21) and a weak (9) agreement. Among them, only 15 were graded with a high level of quality of evidence, underlying the necessity to continue clinical studies in order to improve the risk-to-benefit ratio of glucose control.

[Results of studies in critical care medicine in the year 2009 : update]

Critical care medicine plays an important role for the medical and economic success of hospitals. Knowledge and implementation of recent relevant studies are prerequisites for high quality intensive care medicine. The aim of the present manuscript is to present an overview of the most important publications in intensive care medicine in 2009 and comment on their clinical relevance. It has to be recognized that the cited studies are chosen according to the view of the authors. In 2009 many large randomized studies with high patient numbers were published. Main topics in 2009 were the therapy of lung failure, analgosedation and sepsis therapy. New trends are bedside echocardiography and telemedicine. Unfortunately, a magic bullet has not been identified last year. The focus is still on team education and guideline-assisted therapy.

Incidence of hypoglycemia with tight glycemic control protocols: a comparative study

BACKGROUND

Comparison of hypoglycemia incidence among tight glycemic control (TGC) protocols is a crucial aspect that has not been done in previous trials. This study compared the incidence of hypoglycemia using three TGC protocols in critically ill patients.

METHODOLOGY

This was a prospective study of 420 patients over 18 months. Patients were divided into three groups by TGC protocol: A (modified Leuven protocol), B (Georgia Hospital Association protocol, target blood glucose [BG] 80-110 mg/dL), and C (modified Georgia Hospital Association protocol, target BG 90-140 mg/dL). End points included differences in the incidence of first-degree hypoglycemia (BG <or= 60 mg/dL), second-degree hypoglycemia (BG <or= 40 mg/dL), and hyperglycemia (BG >or= 180 mg/dL).

RESULTS

A total of 34,497 BG samples were analyzed: group A, 11,202 (32.47%); group B, 9,627 (27.91%); and group C, 13,668 (39.62%). First-degree hypoglycemia was more frequent in group A (348 episodes [3.11%]) compared to group B (209 episodes [2.17%] [odds ratio (OR) 1.45, 95% confidence interval (CI) 1.25-1.172, P = 0.001]) and group C (266 episodes [1.95%] [OR 1.66, 95% CI 1.37-1.89, P = 0.001]). Second-degree hypoglycemia was more frequent in group A (131 episodes [1.17%]) compared to group B (62 episodes [0.64%] [OR 1.83, 95% CI 1.22-1.72, P = 0.001]) and group C (58 episodes [0.42%] [OR 2.77, 95% CI 2.04-3.79, P = 0.001]). No significant difference was found when groups B and C were compared (P = 0.10 and P = 0.06, respectively). Hyperglycemia was significantly more common in group A (2,175 episodes [19.42%]) compared to group B (1,333 episodes [13.83%] [OR 1.49, 95% CI 1.39-1.62, P = 0.001], but there was no significant difference compared to group C (2,560 episodes [18.73%] [P = 0.17]).

CONCLUSIONS

TGC protocols vary in their risk of inducing hypoglycemia. Whether this translates into differences in clinical outcomes such as mortality and adverse effects is still to be determined by future studies.

Dysglycemia following glucocorticoid therapy for acute graft-versus-host disease adversely affects transplantation outcomes

Disordered glucose metabolism is a common complication of glucocorticoid therapy for acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation (HCT). We aimed to examine the impact of dysglycemia on outcomes in 173 recipients of HCT treated with glucocorticoids for aGVHD. A total of 147 of these patients contributed data to a landmark analysis performed at 12 weeks post-HCT. Median aGVHD onset was 21 days (range: 5-79) after transplant. Median duration of glucocorticoid therapy was 381 days (range: 15-1632). Glucose values were obtained from glucocorticoid initiation date to death or last follow-up, resulting in 11,588 total values. The median (range) for each parameter were: maximum 292 mg/dL (128-694), minimum 75 mg/dL (34-142), average 142 mg/dL (86-327), and standard deviation 46 mg/dL (12-108). Baseline diabetes mellitus predicted significantly greater maximum, mean, and standard deviation. With median follow-up of 20 months (range: 3-55), median overall survival (OS) was 33.7 months (95% confidence interval [CI] 16.4-not reached). On multivariable analysis, maximum, average, or standard deviation of glucose values predicted OS and maximum or average glucose values predicted nonrelapse mortality (NRM). Minimum glucose values of (0-60 mg/dL) were associated with worsened OS and increased NRM. Those patients treated with insulin or oral agents suffered significantly worse OS and increased NRM compared to patients who did not need therapy. Finally, those with sustained maximum values >200 mg/dL despite treatment suffered worse OS and increased NRM. These data suggest an independent adverse effect of dysglycemia in patients treated with glucocorticoids for aGVHD, and argue for stringent glycemic control in this setting.

Hypoglycemia is associated with intensive care unit mortality

OBJECTIVE

The implementation of intensive insulin therapy in the intensive care unit is accompanied by an increase in hypoglycemia. We studied the relation between hypoglycemia on intensive care unit mortality, because the evidence on this subject is conflicting.

DESIGN

Retrospective database cohort study.

SETTING

An 18-bed medical/surgical intensive care unit in a teaching hospital (Onze Lieve Vrouwe Gasthuis Hospital, Amsterdam, The Netherlands).

PATIENTS

A total of 5961 patients admitted to from 2004 to 2007 were analyzed. Readmissions and patients with a withholding care policy or with hypoglycemia on the first glucose measurement were excluded. Patients were treated with a computerized insulin algorithm (target glucose range, 72-126 mg/dL).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

All first episodes of hypoglycemia (glucose < or =45 mg/dL) were derived from 154,015 glucose values. Using Poisson regression, the incidence rates for intensive care unit death and incidence rate ratio comparing exposure and nonexposure to hypoglycemia were calculated. Patients were considered to be exposed to hypoglycemia from the event until the end of intensive care unit admittance. We corrected for severity of disease using the daily Sequential Organ Failure Assessment score. Age, sex, cardiothoracic surgery, sepsis, and diabetes mellitus were also included as possible confounders. Two hundred eighty-eight (4.8%) patients experienced at least one episode of hypoglycemia. Median age was 68 yrs (range, 58-75 yrs), 66% were male, and 6.4% died in the intensive care unit. The incidence rate of death in patients exposed to hypoglycemia was 40 per 1000 intensive care unit days compared with 17 per 1000 intensive care unit days in patients without exposure. The adjusted incidence rate ratio for intensive care unit death was 2.1 (95% confidence interval, 1.6-2.8; p < .001).

CONCLUSIONS

Hypoglycemia is related to intensive care unit mortality, also when adjusted for a daily adjudicated measure of disease severity, indicating the possibility of a causal relationship.

Hospital glucose control: safe and reliable glycemic control using enhanced model predictive control algorithm in medical intensive care unit patients

BACKGROUND

The aim of this study was to investigate the performance of the enhanced Model Predictive Control (eMPC) algorithm for glycemic control in medical critically ill patients for the whole length of intensive care unit (ICU) stay.

METHODS

The trial was designed as a single-center, open, noncontrolled clinical investigation in a nine-bed medical ICU in a tertiary teaching hospital. In 20 patients, blood glucose (BG) was controlled with a laptop-based bedside version of the eMPC. Efficacy was assessed by percentage of time within the target range (4.4-6.1 mM; primary end point), mean BG, and BG sampling interval. Safety was assessed by the number of severe hypoglycemic episodes (<2.2 mM).

RESULTS

Twenty patients (69 +/- 11 years old; body mass index, 27.4 +/- 4.5 kg/m(2); APACHE II, 25.5 +/- 5.2) were included for a period of 7.3 days (median; interquartile range, 4.4-10.2 days) in the study. Time within target range was 58.12 +/- 10.05% (mean +/- SD). For all patients with at least 7 days in the ICU, there was no statistically significant difference between the daily mean percentage of times in target range in respect of the averages. Mean arterial BG was 5.8 +/- 0.5 mM, insulin requirement was 101.3 +/- 50.7 IU/day, and mean carbohydrate intake (enteral and parenteral nutrition) was 176.4 +/- 61.9 g/day. Three hypoglycemic episodes occurred in three subjects, corresponding to a rate of 0.02 per treatment day.

CONCLUSIONS

In our single-center, noncontrolled study the eMPC algorithm was a safe and reliable method to control BG in critically medical ICU patients for the whole length of ICU stay.

The Glucosafe system for tight glycemic control in critical care: a pilot evaluation study

PURPOSE

"Glucosafe' is a new model-based decision support system for glycemic control in critical care. Safety and achievement of glycemic goals using the system are tested prospectively.

METHODS

Four penalty functions were developed to balance regimens of nutrition and insulin therapy against model-predicted glycemic outcome. The system advises the regimen where the penalty sum is minimal. An interactive interface allows advice alterations. Ten hyperglycemic patients (median Acute Physiology and Chronic Health Evaluation II, 12.5; interquartile range, 7.5-16.3) from a neuro and trauma intensive care unit were included for pilot testing using Glucosafe for 12 to 14 hours. Glycemic outcomes were compared to the 24-hour intervals before and after intervention.

RESULTS

Hypoglycemia (blood glucose [BG] <3.5 mmol/L) was not observed. Mean log-normal BG +/- standard deviation was reduced from 8.6 +/- 2.4 mmol/L preintervention to 7.0 +/- 1.1 mmol/L during the intervention. Nine patients reached the 4.4- to 6.1-mmol/L band after a mean 5 hours. At 5 hours intervention, mean log-normal BG was 6.7 mmol/L, 40% of measurements were in the 4.4- to 6.1-mmol/L band, and 84% were in the 4.4- to 7.75-mmol/L band.

CONCLUSIONS

Safety was demonstrated with the developed penalty functions. The low BG variance achieved may permit minor adjustments of the penalty function values to reduce average BG if desired.