Severity of insulin resistance in critically ill medical patients

Predictive value of the triglyceride-glucose index for short- and long-term all-cause mortality in patients with critical coronary artery disease: a cohort study from the MIMIC-IV database

BACKGROUND

Triglyceride-glucose (TyG) index is linked to a poor prognosis for cardiovascular condition and is a valid indicator of insulin resistance. This study evaluated the potential predicting usefulness of the TyG index for all-cause mortality, both short- and long-term, for those concerning critical coronary artery disease (CAD).

METHODS

In this study, information from 5452 critically-ill individuals with CAD in intensive care units were gathered from the Medical Information Marketplace in Intensive Care (MIMIC-IV) database. Depending on the TyG index degree, the patients were categorized into three categories. Clinical outcomes included short-term (30-day) and long-term (365-day) all-cause mortality. The corresponding relationships involving the TyG index and clinical outcomes were examined by deploying restricted cubic spline (RCS) regression analysis and Cox proportional risk regression.

RESULTS

An increased TyG index was associated with increased 30-day (Tertile 1: 6.1%, Tertile 2: 7.3%, Tertile 3: 9.2%, P = 0.001) and 365-day (Tertile 1: 15.2%, Tertile 2: 17.0%, Tertile 3: 19.6%, P = 0.002) death rates across all causes. Cox regression with multiple variables indicates that higher TyG indices were linked to higher all-caused mortality hazard ratios throughout the short and long terms, with a larger predictive value for the former. RCS regression analyses suggested that the risk of death was notably and linearly that is associated with TyG index.

CONCLUSIONS

The TyG index is a reliable predictor of all-cause mortality at different stages in critically ill CAD patients, with a higher predictive ability for short-term mortality. Early intervention in patients with elevated TyG index may improve their survival outcomes. Future research should delve into understanding its pathophysiological mechanisms and develop intervention strategies based on the TyG index, providing new insights and strategies to enhance the outlook for critically ill CAD patients.

Impact of the triglyceride-glucose index on 28-day mortality in non-diabetic critically Ill patients with sepsis: a retrospective cohort analysis

INTRODUCTION

Sepsis is a life-threatening condition that poses a globally high mortality rate. Identifying risk factors is crucial. Insulin resistance and the TYG index, associated with metabolic disorders, may play a role. This study explores their correlation with mortality in non-diabetic septic patients.

METHODS

This retrospective cohort study used data from the MIMIC-IV (version 2.1) database, which includes over 50,000 ICU admissions from 2008 to 2019 at Beth Israel Deaconess Medical Center in Boston. We included adult patients with sepsis who were admitted to the intensive care unit in the study. The primary outcome was to evaluate the ability of TYG to predict death at 28-day of hospital admission in patients with sepsis.

RESULTS

The study included 2213 patients with sepsis, among whom 549 (24.8%) died within 28 days of hospital admission. We observed a non-linear association between TYG and the risk of mortality. Compared to the reference group (lower TYG subgroup), the 28-day mortality increased in the higher TYG subgroup, with a fully adjusted hazard ratio of 2.68 (95% CI: 2.14 to 3.36). The area under the curve (AUC) for TYG was 67.7%, higher than for triglycerides alone (AUC = 64.1%), blood glucose (AUC = 62.4%), and GCS (AUC = 63.6%), and comparable to SOFA (AUC = 69.3%). The final subgroup analysis showed no significant interaction between TYG and each subgroup except for the COPD subgroup (interaction P-values: 0.076-0.548).

CONCLUSION

In our study, TYG can be used as an independent predictor for all-cause mortality due to sepsis within 28 days of hospitalization.

Independent effects of the glucose-to-glycated hemoglobin ratio on mortality in critically ill patients with atrial fibrillation

BACKGROUND

The glucose-to-glycated hemoglobin ratio (GAR) represents stress hyperglycemia, which has been closely associated with adverse outcomes in cardio-cerebrovascular diseases. No studies have examined the association between stress hyperglycemia and atrial fibrillation (AF) in critically ill patients. This study aims to explore the relationship between GAR and the prognosis of critically ill patients with AF.

METHODS

A retrospective cohort of patients was selected from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The GAR was calculated based on fasting blood glucose and glycated hemoglobin levels measured after admission. The primary outcome was the 30-day mortality rate, with secondary outcomes being the 90-day and 365-day mortality rates. The GAR was divided into tertiles, and Kaplan-Meier analysis was employed to compare differences in mortality rates between groups. The Cox proportional hazards model and restricted cubic splines (RCS) were utilized to evaluate the relationship between the GAR and mortality. Subsequently, a segmented regression model was constructed to analyze threshold effects in cases where nonlinear relationships were determined.

RESULTS

In this cohort, the second tertile of the GAR exhibited lower mortality rates at 30 days (10.56% vs 6.33% vs 14.51%), 90 days (17.11% vs 10.09% vs 17.88%), and 365 days (25.30% vs 16.15% vs 22.72%). In the third tertile, the risk of mortality at 30 days increased by 165% (HR = 2.65, 95% CI 1.99-3.54, p < 0.001), at 90 days increased by 113% (HR = 2.13, 95% CI 1.68-2.70, p < 0.001), and at 365 days increased by 70% (HR = 1.70, 95% CI 1.68-2.70, p < 0.001). The association between the GAR and patient mortality demonstrated a "J-shaped" non-linear correlation. Once the GAR exceeded 15.915, each incremental unit increase in the ratio was associated with a 27.2% increase in the risk of 30-day mortality in critically ill atrial fibrillation patients (HR = 1.262, 95% CI 1.214-1.333, p < 0.001).

CONCLUSION

The GAR is associated with both short-term and long-term mortality in critically ill patients with AF in a J-shaped relationship. Both low and excessively high GAR values indicate poor prognosis.

The triglyceride-glucose index: a novel predictor of stroke and all-cause mortality in liver transplantation recipients

BACKGROUND

The triglyceride-glucose (TyG) index, identified as a reliable indicator of insulin resistance (IR), was reported to be associated with stroke recurrence and morbidity in the general population and critically ill patients. However, the relationship in liver transplantation (LT) recipients remains unknown. This study aimed to investigate the correlation between the TyG index and post-LT stroke along with all-cause mortality and further assess the influence of IR on the LT recipients' prognosis.

METHODS

The retrospective cohort study enrolled 959 patients who underwent LT at a university-based medical centre between January 2015 and January 2021. The participants were divided into three groups according to their TyG index tertiles. The primary outcome was post-LT stroke. Multivariate logistic regression, COX proportional hazards regression, and restricted cubic spline RCS were used to examine the association between the TyG index and outcomes in LT recipients.

RESULTS

With a median TyG index of 8.23 (7.78-8.72), 780 (87.18% males) patients were eventually included. The incidence of post-LT stroke was 5.38%, and the in-hospital, 1-year, and 3-year mortality rates were 5.54%, 13.21%, and 15.77%, respectively. Multivariate regression analysis showed an independent association between the TyG index and an increased risk of post-LT stroke [adjusted odds ratio (aOR), 3.398 (95% confidence interval [CI]: 1.371-8.426) P = 0. 008], in-hospital mortality [adjusted hazard ratio (aHR), 2.326 (95% CI: 1.089-4.931) P = 0.025], 1-year mortality [aHR, 1.668 (95% CI: 1.024-2.717) P = 0.039], and 3-year mortality [aHR, 1.837 (95% CI: 1.445-2.950) P = 0.012]. Additional RCS analysis also suggested a linear increase in the risk of postoperative stroke with elevated TyG index (P for nonlinearity = 0.480).

CONCLUSIONS

The TyG index may be a valuable and reliable indicator for assessing stroke risk and all-cause mortality in patients undergoing LT, suggesting its potential relevance in improving risk stratification during the peri-LT period.

Independent effect of the triglyceride-glucose index on all-cause mortality in critically ill patients with chronic obstructive pulmonary disease and asthma: A retrospective cohort study

BACKGROUND

The triglyceride-glucose (TyG) index serves as a reliable proxy for insulin resistance (IR). IR has been linked to heightened incidence, prevalence, or severity of chronic obstructive pulmonary disease (COPD) and asthma. Prior research indicates that critically ill patients are prone to developing IR. Nevertheless, few studies have delved into the correlation between IR and all-cause mortality in critically ill patients with COPD and asthma. Therefore, the aim of this study is to explore the association between the TyG index and all-cause mortality in patients with COPD and asthma, with the goal of assessing the impact of IR on the prognosis of this patient population.

METHODS

This is a retrospective study, and all data are from the Medical Information Mart for Intensive Care IV (MIMIC-IV) critical care database. This study included 684 ICU patients with COPD and asthma and divided them into quartiles based on TyG index levels. The primary outcomes of this study were all-cause mortality during follow-up, encompassing mortality at 30 days, 90 days, and 180 days. The Kaplan-Meier analysis was used to compare all-cause mortality among the above four groups. Cox proportional hazards analyses were performed to examine the association between TyG index and all-cause mortality in critically ill patients with COPD and asthma. Restricted cubic spline analysis was used to assess potential nonlinear association between the TyG index and the primary outcome.

RESULTS

A total of 684 patients (53.9% female) were included. The 90-days all-cause mortality rate and 180-days all-cause mortality were 11.7% and 12.3%, respectively. Kaplan-Meier analysis revealed a significant association between the TyG index and both 90-days all-cause mortality (log-rank p = .039) and 180-days all-cause mortality (log-rank p = .017). Cox proportional hazards analysis revealed a significant association between the TyG index and 90-days all-cause mortality in both the unadjusted model (HR, 1.30 [95% CI 1.08-1.57] p = .005) and the model adjusted for age, gender, and diabetes (HR, 1.38 [95% CI 1.15-1.67] p < .001). Similarly, the TyG index was associated with 180-days all-cause mortality in the unadjusted model (HR, 1.30 [95% CI 1.09-1.56] p = .004) and the model adjusted for age, sex, and diabetes (HR, 1.38 [95% CI 1.15-1.66] p < .001). The restricted cubic splines (RCS) regression model indicated a significant nonlinear association between the TyG index and both 90-days and 180-days all-cause mortality. Specifically, TyG index >4.8 was associated with an increased risk of mortality at both 90 days and 180 days.

CONCLUSIONS

In summary, our results extend the utility of the TyG index to critically ill patients with COPD and asthma. Our study shows that the TyG index is a potential predictor of all-cause mortality in critically ill patients with COPD and asthma. In addition, in patients with a TyG index exceeding 4.8, there was a heightened risk of mortality. Measuring the TyG index may help with risk stratification and prognosis prediction in critically ill patients with COPD and asthma. Further prospective studies are needed to confirm our findings.

Association of dynamic change of triglyceride-glucose index during hospital stay with all-cause mortality in critically ill patients: a retrospective cohort study from MIMIC IV2.0

BACKGROUND

Biomarker of insulin resistance, namely triglyceride-glucose index, is potentially useful in identifying critically ill patients at high risk of hospital death. However, the TyG index might have variations over time during ICU stay. Hence, the purpose of the current research was to verify the associations between the dynamic change of the TyG index during the hospital stay and all-cause mortality.

METHODS

The present retrospective cohort study was conducted using the Medical Information Mart for Intensive Care IV 2.0 (MIMIC-IV) critical care dataset, which included data from 8835 patients with 13,674 TyG measurements. The primary endpoint was 1-year all-cause mortality. Secondary outcomes included in-hospital all-cause mortality, the need for mechanical ventilation during hospitalization, length of stay in the hospital. Cumulative curves were calculated using the Kaplan-Meier method. Propensity score matching was performed to reduce any potential baseline bias. Restricted cubic spline analysis was also employed to assess any potential non-linear associations. Cox proportional hazards analyses were performed to examine the association between the dynamic change of TyG index and mortality.

RESULTS

The follow-up period identified a total of 3010 all-cause deaths (35.87%), of which 2477 (29.52%) occurred within the first year. The cumulative incidence of all-cause death increased with a higher quartile of the TyGVR, while there were no differences in the TyG index. Restricted cubic spline analysis revealed a nearly linear association between TyGVR and the risk of in-hospital all-cause mortality (P for non-linear = 0.449, P for overall = 0.004) as well as 1-year all-cause mortality (P for non-linear = 0.909, P for overall = 0.019). The area under the curve of all-cause mortality by various conventional severity of illness scores significantly improved with the addition of the TyG index and TyGVR. The results were basically consistent in subgroup analysis.

CONCLUSIONS

Dynamic change of TyG during hospital stay is associated with in-hospital and 1-year all-cause mortality, and may be superior to the effect of baseline TyG index.

Association between TyG index and long-term mortality of critically ill patients: a retrospective study based on the MIMIC Database

OBJECTIVE

To evaluate the association of triglyceride-glucose (TyG) index on admission with outcomes of critically ill patients.

DESIGN

A retrospective study.

SETTING

A population-based cohort study of Medical Information Mart for Intensive Care III Database (MIMIC III).

PARTICIPANTS

All intensive care unit admissions were extracted from MIMIC III.

MAIN OUTCOME MEASURES

The TyG index was calculated as ln [triglycerides (mg/dL)×glucose (mg/dL)/2]. The primary endpoint was 360-day mortality.

RESULTS

A total of 3902 patients with an average age of 63.1±15.9 years old were enrolled, including 1623 (41.6%) women. The 360-day mortality was lower in a higher TyG group. Compared with the lowest TyG group, the HR of 360-day mortality was 0.79 (95% CI (0.66, 0.95); p=0.011) in the fully adjusted Cox model and 0.71 (95% CI (0.59, 0.85); p<0.001) in the stepwise Cox model. In the subgroup analysis, an interaction effect was detected between TyG index and gender.

CONCLUSIONS

A lower TyG index was associated with the risk of 360-day mortality in critically ill patients, which could be a predictor of long-term survival of critically ill patients.

Impact of Different Crystalloids on the Blood Glucose Levels of Nondiabetic Patients Undergoing Major Elective Surgeries

Background This study aimed to compare intraoperative blood sugar level fluctuations between a group of patients receiving Ringer's lactate (RL) fluid as maintenance fluid and another group receiving 0.45% dextrose normal saline with 20 mmol/liter potassium. Materials and methods  This randomized double-blind study was conducted on 68 nondiabetic patients undergoing elective major surgeries at R. Laxminarayanappa Jalappa Hospital, Sri Devaraj Urs Medical College, Kolar, during the academic year from Jan 2021 to May 2022. Informed consent was obtained from these patients concerning their participation in this study. There were two groups of patients: Ringer lactate (RL) was administered to group A, and 0.45% dextrose normal saline and 20 mmol/L potassium chloride (KCl) were administered to group B. The vitals and blood glucose levels were measured among the patients. A p-value of 0.05 was considered statistically important. Results The mean age of the patients was found to be 43.60 ± 15 years, with comparable age and gender distribution between the groups. On comparison of the mean blood glucose levels immediately after induction was not important between the groups. The mean levels were comparable between the groups (p>0.05). After completion of the surgery, the mean blood glucose level significantly increased in group B patients when compared to those in group A (p<0.05). Conclusion The study found a substantial increase in intraoperative blood glucose levels among patients receiving 0.45% dextrose normal saline with 20 mmol/liter potassium instead of RL solution as maintenance fluid.

Triglyceride-glucose index linked to all-cause mortality in critically ill patients: a cohort of 3026 patients

BACKGROUND

Triglyceride-glucose (TyG) index as a reliable surrogate of insulin resistance (IR) has been shown to be related to adverse clinical outcomes in patients with acute coronary syndrome, heart failure, ischemic stroke and so on. However, the relationship between TyG index and all-cause mortality in intensive care unit (ICU) patients remains unknown. The purpose of this study was to investigate the correlation between TyG index and all-cause mortality to evaluate the impact of IR on the prognosis of this population.

METHODS

This was a retrospective observational study that included 3026 patients who had an initial triglyceride and glucose data on the first day of ICU admission, and all data were extracted from the Medical Information Mart for Intensive Care III (MIMIC-III) database. These patients were grouped into quartiles (Q1-Q4) according to TyG index. The Kaplan-Meier analysis was used to compare all-cause mortality among the above four groups. Cox proportional hazards analyses were performed to examine the association between TyG index and all-cause mortality.

RESULTS

During 10.46 years of follow-up, 1148 (37.9%) patients died, of which 350 (11.6%) occurred during the hospital stay and 258 (8.5%) occurred during the ICU stay. Kaplan-Meier analysis showed that the risk of all-cause mortality was significantly higher in patients with higher TyG index (log-rank P = 0.021). Multivariable Cox proportional hazards analyses showed that the TyG index was an independent risk predictor of ICU death (HR: 1.72, 95% CI 1.18-2.52, P = 0.005) and hospital death (HR: 2.19, 95% CI 1.59-3.03, P < 0.001), and each 1-unit increased in the TyG index, a 1.19-fold increase in the risk of death during the hospital stay.

CONCLUSIONS

TyG index is strongly related to the all-cause mortality increasing in critically ill patients. This finding indicates that the TyG index might be useful in identifying people at high risk of ICU death and hospital death.

Impact of prolonged requirement for insulin on 90-day mortality in critically ill patients without previous diabetic treatments: a post hoc analysis of the CONTROLING randomized control trial

BACKGROUND

Stress hyperglycemia can persist during an intensive care unit (ICU) stay and result in prolonged requirement for insulin (PRI). The impact of PRI on ICU patient outcomes is not known. We evaluated the relationship between PRI and Day 90 mortality in ICU patients without previous diabetic treatments.

METHODS

This is a post hoc analysis of the CONTROLING trial, involving 12 French ICUs. Patients in the personalized glucose control arm with an ICU length of stay ≥ 5 days and who had never previously received diabetic treatments (oral drugs or insulin) were included. Personalized blood glucose targets were estimated on their preadmission usual glycemia as estimated by their glycated A1c hemoglobin (HbA1C). PRI was defined by insulin requirement. The relationship between PRI on Day 5 and 90-day mortality was assessed by Cox survival models with inverse probability of treatment weighting (IPTW). Glycemic control was defined as at least one blood glucose value below the blood glucose target value on Day 5.

RESULTS

A total of 476 patients were included, of whom 62.4% were male, with a median age of 66 (54-76) years. Median values for SAPS II and HbA1C were 50 (37.5-64) and 5.7 (5.4-6.1)%, respectively. PRI was observed in 364/476 (72.5%) patients on Day 5. 90-day mortality was 23.1% in the whole cohort, 25.3% in the PRI group and 16.1% in the non-PRI group (p < 0.01). IPTW analysis showed that PRI on Day 5 was not associated with Day 90 mortality (_IPTWHR = 1.22; CI 95% 0.84-1.75; p = 0.29), whereas PRI without glycemic control was associated with an increased risk of death at Day 90 (_IPTWHR = 3.34; CI 95% 1.26-8.83; p < 0.01).

CONCLUSION

In ICU patients without previous diabetic treatments, only PRI without glycemic control on Day 5 was associated with an increased risk of death. Additional studies are required to determine the factors contributing to these results.

Stress Hyperglycemia, Diabetes Mellitus and COVID-19 Infection: Risk Factors, Clinical Outcomes and Post-Discharge Implications

The novel severe acute respiratory distress syndrome-coronavirus 2 (SARS-CoV-2) has caused one of the most substantial pandemics that has affected humanity in the last century. At the time of the preparation of this review, it has caused the death of around 5 million people around the globe. There is ample evidence linking higher mortality risk rates from Coronavirus disease-19 (COVID-19) with male gender, advancing age and comorbidities, such as obesity, arterial hypertension, cardiovascular disease, chronic obstructive pulmonary disease, diabetes mellitus, and cancer. Hyperglycemia has been found to be accompanying COVID-19 not only in individuals with overt diabetes. Many authors claim that blood glucose levels should also be monitored in non-diabetic patients; moreover, it has been confirmed that hyperglycemia worsens the prognosis even without pre-existing diabetes. The pathophysiological mechanisms behind this phenomenon are complex, remain controversial, and are poorly understood. Hyperglycemia in the setting of COVID-19 could be a consequence of deterioration in pre-existing diabetes, new-onset diabetes, stress-induced or iatrogenic due to substantial usage of corticosteroids within the context of a severe COVID-19 infection. It is also plausible that it might be a result of adipose tissue dysfunction and insulin resistance. Last but not least, SARS-CoV-2 is also claimed to trigger sporadically direct β-cell destruction and β-cell autoimmunity. Pending further validations with longitudinal data are needed to legitimize COVID-19 as a potential risk factor for the development of diabetes. Hereby, we present an emphasized critical review of the available clinical data in an attempt to unravel the complex mechanisms behind hyperglycemia in COVID-19 infection. The secondary endpoint was to evaluate the bidirectional relationship between COVID-19 and diabetes mellitus. As the worldwide pandemic is still expanding, demand for answering these questions is arising. It will be of immense help for the management of COVID-19 patients, as well as for the implementation of post-discharge policies for patients with a high risk of developing diabetes.

Acute pancreatitis-induced islet dysfunction in ferrets

BACKGROUND

/Objectives: The pathogenesis of hyperglycemia during acute pancreatitis (AP) remains unknown due to inaccessibility of human tissues and lack of animal models. We aimed to develop an animal model to study the mechanisms of hyperglycemia and impaired glucose tolerance in AP.

METHODS

We injected ferrets with intraperitoneal cerulein (50 μg/kg, 9 hourly injections) or saline. Blood samples were collected for glucose (0, 4, 8, 12, 24h); TNF-α, IL-6 (6h); amylase, lipase, insulin, glucagon, pancreatic polypeptide (PP), glucagon-like peptide-1 (GLP-1), and gastric inhibitory polypeptide (GIP) (24h). Animals underwent oral glucose tolerance test (OGTT), mixed meal tolerance test (MMTT) at 24h or 3 months, followed by harvesting pancreas for histopathology and immunostaining.

RESULTS

Cerulein-injected ferrets exhibited mild pancreatic edema, neutrophil infiltration, and elevations in serum amylase, lipase, TNF-α, IL-6, consistent with AP. Plasma glucose was significantly higher in ferrets with AP at all time points. Plasma glucagon, GLP-1 and PP were significantly higher in cerulein-injected animals, while plasma insulin was significantly lower compared to controls. OGTT and MMTT showed abnormal glycemic responses with higher area under the curve. The hypoglycemic response to insulin injection was completely lost, suggestive of insulin resistance. OGTT showed low plasma insulin; MMTT confirmed low insulin and GIP; abnormal OGTT and MMTT responses returned to normal 3 months after cerulein injection.

CONCLUSIONS

Acute cerulein injection causes mild acute pancreatitis in ferrets and hyperglycemia related to transient islet cell dysfunction and insulin resistance. The ferret cerulein model may contribute to the understanding of hyperglycemia in acute pancreatitis.

Could Exogenous Insulin Ameliorate the Metabolic Dysfunction Induced by Glucocorticoids and COVID-19?

The finding that high-dose dexamethasone improves survival in those requiring critical care due to COVID-19 will mean much greater usage of glucocorticoids in the subsequent waves of coronavirus infection. Furthermore, the consistent finding of adverse outcomes from COVID-19 in individuals with obesity, hypertension and diabetes has focussed attention on the metabolic dysfunction that may arise with critical illness. The SARS coronavirus itself may promote relative insulin deficiency, ketogenesis and hyperglycaemia in susceptible individuals. In conjunction with prolonged critical care, these components will promote a catabolic state. Insulin infusion is the mainstay of therapy for treatment of hyperglycaemia in acute illness but what is the effect of insulin on the admixture of glucocorticoids and COVID-19? This article reviews the evidence for the effect of insulin on clinical outcomes and intermediary metabolism in critical illness.

Impact of obesity and diabetes mellitus in critically ill patients with SARS-CoV-2

PURPOSE

Evaluate the associations of obesity and diabetes with the risk of mortality in critically ill patients infected with SARS-CoV-2.

MATERIALS AND METHODS

This cohort study included 115 adult patients admitted to the ICU with SARS-CoV-2 pneumonia. Anthropometric variables and biochemical (C-reactive protein, ferritin, leukocyte, neutrophils, and fibrinogen) were measured. Multivariate logistic regression analyses were used to investigate the associations.

RESULTS

Mean age was 50.6±11.2 years, 68.7% were male. Median BMI was 30.9kg/m². All patients had invasive mechanical ventilation. Patients with diabetes had increased risk of mortality with OR of 2.86 (CI 95% 1.1-7.4, p=0.026); among those patients who, in addition to diabetes had obesity, the risk was de 3.17 (CI 95% 1.9-10.2, p=0.038). Patients with obesity had 1.25 times greater risk of developing a severe SARS-CoV-2 infection (95% CI 1.09-1.46, p=0.025). Negative correlation was observed between BMI and the PaO2/FiO2 ratio (r=-0.023, p<0.05). Obese patients required more days of mechanical ventilation and longer hospital stay compared to non-obese patients.

CONCLUSIONS

Diabetes and obesity are risk factors for increasing severity of SARS-CoV-2 infection, and they are both associated with an increase in mortality.

Increased insulin resistance in intensive care: longitudinal retrospective analysis of glycaemic control patients in a New Zealand ICU

BACKGROUND

Critical care populations experience demographic shifts in response to trends in population and healthcare, with increasing severity and/or complexity of illness a common observation worldwide. Inflammation in critical illness impacts glucose-insulin metabolism, and hyperglycaemia is associated with mortality and morbidity. This study examines longitudinal trends in insulin sensitivity across almost a decade of glycaemic control in a single unit.

METHODS

A clinically validated model of glucose-insulin dynamics is used to assess hour-hour insulin sensitivity over the first 72 h of insulin therapy. Insulin sensitivity and its hour-hour percent variability are examined over 8 calendar years alongside severity scores and diagnostics.

RESULTS

Insulin sensitivity was found to decrease by 50-55% from 2011 to 2015, and remain low from 2015 to 2018, with no concomitant trends in age, severity scores or risk of death, or diagnostic category. Insulin sensitivity variability was found to remain largely unchanged year to year and was clinically equivalent (95% confidence interval) at the median and interquartile range. Insulin resistance was associated with greater incidence of high insulin doses in the effect saturation range (6-8 U/h), with the 75th percentile of hourly insulin doses rising from 4-4.5 U/h in 2011-2014 to 6 U/h in 2015-2018.

CONCLUSIONS

Increasing insulin resistance was observed alongside no change in insulin sensitivity variability, implying greater insulin needs but equivalent (variability) challenge to glycaemic control. Increasing insulin resistance may imply greater inflammation and severity of illness not captured by existing severity scores. Insulin resistance reduces glucose tolerance, and can cause greater incidence of insulin saturation and resultant hyperglycaemia. Overall, these results have significant clinical implications for glycaemic control and nutrition management.

Whyte M. Diabetes, obesity and COVID-19: A complex interplay

With the accumulation of observational data showing an association of metabolic co-morbidities with adverse outcomes from COVID-19, there is a need to disentangle the contributions of pre-existing macro- and microvascular disease, obesity and glycaemia. This article outlines the complex mechanistic and clinical interplay between diabetes and COVID-19, the clinical and research questions which arise from this relationship, and the types of studies needed to answer those questions. The authors are clinicians and academics working in diabetes and obesity medicine, but the article is pitched to an audience of generalists with clinical experience of or interest in the management of COVID-19.

Is "Leptin Resistance" Another Key Resistance to Manage Type 2 Diabetes?

Although novel pharmacological options for the treatment of type 2 diabetes mellitus (DM2) have been observed to modulate the functionality of several key organs in glucose homeostasis, successful regulation of insulin resistance (IR), body weight management, and pharmacological treatment of obesity remain notable problems in endocrinology. Leptin may be a pivotal player in this scenario, as an adipokine which centrally regulates appetite and energy balance. In obesity, excessive caloric intake promotes a low-grade inflammatory response, which leads to dysregulations in lipid storage and adipokine secretion. In turn, these entail alterations in leptin sensitivity, leptin transport across the blood-brain barrier and defects in post-receptor signaling. Furthermore, hypothalamic inflammation and endoplasmic reticulum stress may increase the expression of molecules which may disrupt leptin signaling. Abundant evidence has linked obesity and leptin resistance, which may precede or occur simultaneously to IR and DM2. Thus, leptin sensitivity may be a potential early therapeutic target that demands further preclinical and clinical research. Modulators of insulin sensitivity have been tested in animal models and small clinical trials with promising results, especially in combination with agents such as amylin and GLP-1 analogs, in particular, due to their central activity in the hypothalamus.

Energy, Protein, Carbohydrate, and Lipid Intakes and Their Effects on Morbidity and Mortality in Critically Ill Adult Patients: A Systematic Review

The guidelines for nutritional support in critically ill adult patients differ in various aspects. The optimal amount of energy and nutritional substrates supplied is important for reducing morbidity and mortality, but unfortunately this is not well known, because the topic is complex and every patient is individual. The aim of this review was to gather recent pertinent information concerning the nutritional support of critically ill patients in the intensive care unit (ICU) with respect to the energy, protein, carbohydrate, and lipid intakes and the effect of their specific utilization on morbidity and mortality. Enteral nutrition (EN) is generally recommended over parenteral nutrition (PN) and is beneficial when administered within 24-48 h after ICU admission. In contrast, early PN does not provide substantial advantages in terms of morbidity and mortality, and the time when it is safe and beneficial remains unclear. The most advantageous recommendation seems to be administration of a hypocaloric (<20 kcal · kg^-1 · d^-1), high-protein diet (amino acids at doses of ≥2 g · kg^-1 · d^-1), at least during the first week of critical illness. Another important factor for reducing morbidity is the maintenance of blood glucose concentrations at 120-150 mg/dL, which is accomplished with the use of insulin and lower doses of glucose of 1-2 g · kg^-1 · d^-1, because this prevents the risk of hypoglycemia and is associated with a better prognosis according to recent studies. A fat emulsion is used as a source of required calories because of insulin resistance in the majority of patients. In addition, lipid oxidation in these patients is ∼25% higher than in healthy subjects.

Stress Hyperglycemia During Surgery and Anesthesia: Pathogenesis and Clinical Implications

Numerous studies have demonstrated an association between hyperglycemia in the perioperative period and adverse clinical outcomes. Many patients who experience hyperglycemia while hospitalized do not have a known history of diabetes and experience a transient phenomenon often described as "stress hyperglycemia" (SH). We discuss the epidemiology and pathogenesis of SH as well as evidence to date regarding predisposing factors and outcomes. Further research is needed to identify the long-term sequelae of SH as well as perioperative measures that may modulate glucose elevations and optimal treatment strategies.

Low energy intake during the first week in an emergency intensive care unit is associated with reduced duration of mechanical ventilation in critically ill, underweight patients: a single-center retrospective chart review

BACKGROUND

Although nutrition support is essential in intensive care units, optimal energy intake remains unclear. Here, we assessed the influence of energy intake on outcomes of critically ill, underweight patients.

METHODS

A retrospective chart review was conducted in patients with body mass index (BMI) of <20.0 kg/m(2) in an emergency intensive care unit (EICU). Patients were categorized into 4 groups by initial Sequential Organ Failure Assessment score (I-SOFA) and average daily energy intake during the first week: group M-1, I-SOFA ≤8 and <16 kcal/kg/d; group M-2, I-SOFA ≤8 and ≥16 kcal/kg/d; group S-1, I-SOFA >8 and <16 kcal/kg/d; and group S-2, I-SOFA >8 and ≥16 kcal/kg/d.

RESULTS

The study included 51 patients with a median age of 69 years. No significant differences were noted in all-cause mortality and length of stay in the EICU and hospital between groups M-1 and M-2 or groups S-1 and S-2. The mechanical ventilation duration (MVD) was significantly shorter in group M-1 than M-2 (2.7 [1.0-5.7] vs 9.2 [4.2-17.4] days; P = .040) and in group S-1 than S-2 (3.1 [0.7-6.0] vs 8.8 [6.1-23.1] days; P = .006). The number of patients who underwent tracheostomy in hospital was significantly lower in group S-1 than in S-2 (20% vs 32%; P = .002). Multivariable analyses to adjust for confounders revealed that average energy intake during the first week in EICU was a significant factor independently associated with MVD but not with the requirement of tracheostomy.

CONCLUSION

Reduced energy intake during the first week in EICU was associated with a reduced MVD in clinically ill patients with BMI <20.0 kg/m(2).

Performance assessment of a glucose control protocol in septic patients with an automated intermittent plasma glucose monitoring device

BACKGROUND & AIMS

The optimal level and modality of glucose control in critically ill patients is still debated. A protocolized approach and the use of nearly-continuous technologies are recommended to manage hyperglycemia, hypoglycemia and glycemic variability. We recently proposed a pato-physiology-based glucose control protocol which takes into account patient glucose/carbohydrate intake and insulin resistance. Aim of the present investigation was to assess the performance of our protocol with an automated intermittent plasma glucose monitoring device (OptiScanner™ 5000).

METHODS

OptiScanner™ was used in 6 septic patients, providing glucose measurement every 15' from a side-port of an indwelling central venous catheter. Target level of glucose was 80-150 mg/dL. Insulin infusion and kcal with nutritional support were also recorded.

RESULTS

6 septic patients were studied for 319 h (1277 measurements); 58 [45-65] hours for each patient (measurements/patient: 231 [172-265]). Blood glucose was at target for 93 [90-98]% of study time. Mean plasma glucose was 126 ± 11 mg/dL. Only 3 hypoglycemic episodes (78, 78, 69 mg/dL) were recorded. Glucose variability was limited: plasma glucose coefficient of variation was 11.7 ± 4.0% and plasma glucose standard deviation was 14.3 ± 5.5 mg/dL.

CONCLUSIONS

The local glucose control protocol achieved satisfactory glucose control in septic patients along with a high degree of safeness. Automated intermittent plasma glucose monitoring seemed useful to assess the performance of the protocol.

The glucose dysmetabolism in the acute phase of non-diabetic ST-elevation myocardial infarction: from insulin resistance to hyperglycemia

In the setting of acute myocardial infarction, hyperglycemia and acute insulin resistance may represent a stress response to myocardial injury mainly related to acute catecholamine release. By measuring glucose values and insulin resistance (Homeostatic Model Assessment index-HOMA), we evaluated in 356 non-diabetic patients with ST-elevation myocardial infarction (STEMI) undergone mechanical revascularization: (a) the acute glycometabolic response by evaluating insulin resistance, glucose levels, and their combination and (b) whether insulin resistance and increased glucose values (and their combination) are able to affect in-Intensive Cardiac Care Unit (ICCU) mortality and complications. In the overall population, 226 (63.5%) patients showed glucose values ≤140 mg/dl (group B), while 130 patients had glucose values >140 mg/dl (group A) (36.5%). Within group B, insulin resistance (as inferred by positive HOMA index) was present in 125 patients (55.3%), whereas 101 patients (44.7%) exhibited normal values of HOMA index. Within group A, 109 patients (83.8%) were insulin resistant, while 21 patients (16.2%) had normal values of HOMA index. At multivariable analysis, glucose values were independently associated with in-ICCU mortality (OR: 7.387; 95% CI 2.701-20.201; P < 0.001) and complications (OR: 1.786; 95% CI 1.089-2.928; P = 0.022). In the early phase of STEMI, the acute glycometabolic response to stress is heterogeneous (ranging from no insulin resistance to glucose levels >140 mg/dl and, finally, to the combination of increased glucose values and insulin resistance). Increased glucose values are stronger prognostic factors since they are independently associated with in-ICCU mortality and complications.

Critical illness myopathy and GLUT4: significance of insulin and muscle contraction

RATIONALE

Critical illness myopathy (CIM) has no known cause and no treatment. Immobilization and impaired glucose metabolism are implicated.

OBJECTIVES

We assessed signal transduction in skeletal muscle of patients at risk for CIM. We also investigated the effects of evoked muscle contraction.

METHODS

In a prospective observational and interventional pilot study, we screened 874 mechanically ventilated patients with a sepsis-related organ-failure assessment score greater than or equal to 8 for 3 consecutive days in the first 5 days of intensive care unit stay. Thirty patients at risk for CIM underwent euglycemic-hyperinsulinemic clamp, muscle microdialysis studies, and muscle biopsies. Control subjects were healthy. In five additional patients at risk for CIM, we performed corresponding analyses after 12-day, daily, unilateral electrical muscle stimulation with the contralateral leg as control.

MEASUREMENTS AND MAIN RESULTS

We performed successive muscle biopsies and assessed systemic insulin sensitivity and signal transduction pathways of glucose utilization at the mRNA and protein level and glucose transporter-4 (GLUT4) localization in skeletal muscle tissue. Skeletal muscle GLUT4 was trapped at perinuclear spaces, most pronounced in patients with CIM, but resided at the sarcolemma in control subjects. Glucose metabolism was not stimulated during euglycemic-hyperinsulinergic clamp. Insulin signal transduction was competent up to p-Akt activation; however, p-adenosine monophosphate-activated protein kinase (p-AMPK) was not detectable in CIM muscle. Electrical muscle stimulation increased p-AMPK, repositioned GLUT4, locally improved glucose metabolism, and prevented type-2 fiber atrophy.

CONCLUSIONS

Insufficient GLUT4 translocation results in decreased glucose supply in patients with CIM. Failed AMPK activation is involved. Evoked muscle contraction may prevent muscle-specific AMPK failure, restore GLUT4 disposition, and diminish protein breakdown. Clinical trial registered with http://www.controlled-trials.com (registration number ISRCTN77569430).

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.

Current recommended parenteral protein intakes do not support protein synthesis in critically ill septic, insulin-resistant adolescents with tight glucose control

OBJECTIVE

To investigate the effects of insulin infusion and increased parenteral amino acid intakes on whole body protein balance, glucose kinetics, and lipolysis in critically ill, insulin-resistant, septic adolescents.

DESIGN

A single-center, randomized, crossover study.

SETTING

A medicosurgical intensive care unit in a tertiary university hospital.

PATIENTS

Nine critically ill, septic adolescents (age 15.0 ± 1.2 yrs, body mass index 20 ± 4 kg m(-2)) receiving total parenteral nutrition.

INTERVENTIONS

Patients received total parenteral nutrition with standard (1.5 g · kg(-1) · day(-1)) and high (3.0 g · kg(-1) · day(-1)) amino acid intakes in a 2-day crossover setting, randomized to the order in which they received it. On both study days, we conducted a primed, constant, 7-hr stable isotope tracer infusion with [1-(13)C]leucine, [6,6-(2)H(2)]glucose, and [1,1,2,3,3-(2)H(5)]glycerol, in combination with a hyperinsulinemic euglycemic clamp during the last 3 hrs.

MEASUREMENTS AND MAIN RESULTS

Insulin decreased protein synthesis at standard amino acid and high amino acid intakes (p < .01), while protein breakdown decreased with insulin at standard amino acid intake (p < .05) but not with the high amino acid intake. High amino acid intake improved protein balance (p < .05), but insulin did not have an additive effect. There was significant insulin resistance with an M value of ~3 (mg · kg(-1) · min(-1))/(mU · mL(-1)) which was 30% of reported normal values. At high amino acid intake, endogenous glucose production was not suppressed by insulin and lipolysis rates increased.

CONCLUSION

The current recommended parenteral amino acid intakes are insufficient to maintain protein balance in insulin-resistant patients during tight glucose control. During sepsis, insulin decreases protein synthesis and breakdown, and while high amino acid intake improves protein balance, its beneficial effects may be offset by enhanced endogenous glucose production and lipolysis, raising concerns that insulin resistance may have been exacerbated and that gluconeogenesis may have been favored by high amino acid intakes. Dose-response studies on the effect of the level of amino acid intakes (protein) on energy metabolism are needed.

Glycemic control during critical illness

Tight glucose control in the intensive care unit was associated with an improved survival in one pioneering study, but this finding was not confirmed in seven other trials. The reasons underlying this discrepancy are not fully elucidated, indicating that an improved understanding of the physiology and pathophysiology of blood glucose (BG) regulation is needed. Potential reasons for the discrepancies between the studies also include: case-mix, with different optimal BG in different types of patients; hypoglycemia, which is associated with a poor outcome; and the magnitude of glucose variability. Safe and effective glucose control will require progress in the definition of optimal BG, and in the measurement techniques including continuous monitoring insulin algorithms and closed-loop systems.

Puerarin alleviates burn-related procedural pain mediated by P2X(3) receptors

Pain is a major problem after burns. Procedural pain evoked by burn dressing changes is common in patients, and its management is a critical part of treatment in acute burn injuries. Burn pain is very likely the most difficult form of acute pain to treat. ATP contributes to inflammation, and ATP is implicated in peripheral pain signaling via actions upon P2X(3) receptors. Puerarin is extracted from a traditional Chinese medicine and may act on P2X(3) receptor mechanisms. The Visual Analogue Scale (VAS) has been shown to be a sensitive indicator of pain intensity and treatment effects. Peripheral blood mononuclear cells (PBMCs) are involved in nociception or pain after burn injury. Burn patients were randomly divided into normal saline (NS) group (salt solution is saline) and puerarin-treated group and pain (Visual Analogue Scale scores) and inflammation (PBMCs) measured. Burn pain produces a stress response, so blood glucose, insulin, and cortisol levels in burn patients were determined. Furthermore, the expression of P2X(3) protein and mRNA in PBMCs was detected. The VAS scores in the puerarin-treated group were lower than those in NS group. The blood glucose, insulin, and cortisol levels in the puerarin-treated group at post-dressing changes were significantly decreased in comparison with those in NS group. The expression levels of P2X(3) protein and mRNA in PBMCs of burn patients in NS group were significantly increased in comparison with those in the puerarin-treated group. Puerarin can antagonize inflammatory factors (such as ATP) and decrease the upregulated expressions of P2X(3) protein and mRNA in PBMCs after burns to decrease VAS. Thus, puerarin had an analgesic effect on procedural pain in dressing changes of burn patients related to P2X(3) receptors.

Permissive underfeeding and intensive insulin therapy in critically ill patients: a randomized controlled trial

BACKGROUND

Nutritional support has been recognized as an essential part of intensive care unit management. However, the appropriate caloric intake for critically ill patients remains ill defined.

OBJECTIVE

We examined the effect of permissive underfeeding compared with that of target feeding and of intensive insulin therapy (IIT) compared with that of conventional insulin therapy (CIT) on the outcomes of critically ill patients.

DESIGN

This study had a 2 × 2 factorial, randomized, controlled design. Eligible patients were randomly assigned to permissive underfeeding or target feeding groups (caloric goal: 60-70% compared with 90-100% of calculated requirement, respectively) with either IIT or CIT (target blood glucose: 4.4-6.1 compared with 10-11.1 mmol/L, respectively).

RESULTS

Twenty-eight-day all-cause mortality was 18.3% in the permissive underfeeding group compared with 23.3% in the target feeding group (relative risk: 0.79; 95% CI: 0.48, 1.29; P = 0.34). Hospital mortality was lower in the permissive underfeeding group than in the target group (30.0% compared with 42.5%; relative risk: 0.71; 95% CI: 0.50, 0.99; P = 0.04). No significant differences in outcomes were observed between the IIT and CIT groups.

CONCLUSION

In critically ill patients, permissive underfeeding may be associated with lower mortality rates than target feeding. This trial was registered at controlled-trials.com as ISRCTN96294863.

Disturbance of glucose homeostasis after pediatric cardiac surgery

This study aimed to evaluate the time course of perioperative blood glucose levels of children undergoing cardiac surgery for congenital heart disease in relation to endogenous stress hormones, inflammatory mediators, and exogenous factors such as caloric intake and glucocorticoid use. The study prospectively included 49 children undergoing cardiac surgery. Blood glucose levels, hormonal alterations, and inflammatory responses were investigated before and at the end of surgery, then 12 and 24 h afterward. In general, blood glucose levels were highest at the end of surgery. Hyperglycemia, defined as a glucose level higher than 8.3 mmol/l (>150 mg/dl) was present in 52% of the children at the end of surgery. Spontaneous normalization of blood glucose occurred in 94% of the children within 24 h. During surgery, glucocorticoids were administered to 65% of the children, and this was the main factor associated with hyperglycemia at the end of surgery (determined by univariate analysis of variance). Hyperglycemia disappeared spontaneously without insulin therapy after 12-24 h for the majority of the children. Postoperative morbidity was low in the study group, so the presumed positive effects of glucocorticoids seemed to outweigh the adverse effects of iatrogenic hyperglycemia.

Intensive care unit-acquired weakness (ICUAW) and muscle wasting in critically ill patients with severe sepsis and septic shock

Sepsis presents a major health care problem and remains one of the leading causes of death within the intensive care unit (ICU). Therapeutic approaches against severe sepsis and septic shock focus on early identification. Adequate source control, administration of antibiotics, preload optimization by fluid resuscitation and further hemodynamic stabilisation using vasopressors whenever appropriate are considered pivotal within the early-golden-hours of sepsis. However, organ dysfunction develops frequently in and represents a significant comorbidity of sepsis. A considerable amount of patients with sepsis will show signs of severe muscle wasting and/or ICU-acquired weakness (ICUAW), which describes a frequently observed complication in critically ill patients and refers to clinically weak ICU patients in whom there is no plausible aetiology other than critical illness. Some authors consider ICUAW as neuromuscular organ failure, caused by dysfunction of the motor unit, which consists of peripheral nerve, neuromuscular junction and skeletal muscle fibre. Electrophysiologic and/or biopsy studies facilitate further subclassification of ICUAW as critical illness myopathy, critical illness polyneuropathy or critical illness myoneuropathy, their combination. ICUAW may protract weaning from mechanical ventilation and impede rehabilitation measures, resulting in increased morbidity and mortality. This review provides an insight on the available literature on sepsis-mediated muscle wasting, ICUAW and their potential pathomechanisms.

Near-target caloric intake in critically ill medical-surgical patients is associated with adverse outcomes

BACKGROUND

The objective of this study was to determine whether caloric intake independently influences mortality and morbidity of critically ill patients.

METHODS

The study was conducted as a nested cohort study within a randomized controlled trial in a tertiary care intensive care unit (ICU). The main exposure in the study was average caloric intake/target for the first 7 ICU days. The primary outcomes were ICU and hospital mortality. Secondary outcomes included ICU-acquired infections, ventilator-associated pneumonia (VAP), duration of mechanical ventilation days, and ICU and hospital length of stay (LOS). The authors divided patients (n = 523) into 3 tertiles according to the percentage of caloric intake/target: tertile I <33.4%, tertile II 33.4%-64.6%, and tertile III >64.6%. To adjust for potentially confounding variables, the authors assessed the association between caloric intake/target and the different outcomes using multivariate logistic regression for categorical outcomes (tertile I was used as reference) and multiple linear regression for continuous outcomes.

RESULTS

Tertile III was associated with higher adjusted hospital mortality, higher risk of ICU-acquired infections, and a trend toward higher VAP rate. Increasing caloric intake was independently associated with a significant increase in duration of mechanical ventilation, ICU LOS, and hospital LOS.

CONCLUSIONS

The data demonstrate that near-target caloric intake is associated with significantly increased hospital mortality, ICU-acquired infections, mechanical ventilation duration, and ICU and hospital LOS. Further studies are needed to explore whether reducing caloric intake would improve the outcomes in critically ill patients.

Current status of islet cell replacement and regeneration therapy

CONTEXT

Beta cell mass and function are decreased to varying degrees in both type 1 and type 2 diabetes. In the future, islet cell replacement or regeneration therapy may thus offer therapeutic benefit to people with diabetes, but there are major challenges to be overcome.

EVIDENCE ACQUISITION

A review of published peer-reviewed medical literature on beta-cell development and regeneration was performed. Only publications considered most relevant were selected for citation, with particular attention to the period 2000-2009 and the inclusion of earlier landmark studies.

EVIDENCE SYNTHESIS

Islet cell regenerative therapy could be achieved by in situ regeneration or implantation of cells previously derived in vitro. Both approaches are being explored, and their ultimate success will depend on the ability to recapitulate key events in the normal development of the endocrine pancreas to derive fully differentiated islet cells that are functionally normal. There is also debate as to whether beta-cells alone will assure adequate metabolic control or whether it will be necessary to regenerate islets with their various cell types and unique integrated function. Any approach must account for the potential dangers of regenerative therapy.

CONCLUSIONS

Islet cell regenerative therapy may one day offer an improved treatment of diabetes and potentially a cure. However, the various approaches are at an early stage of preclinical development and should not be offered to patients until shown to be safe as well as more efficacious than existing therapy.

Stress hyperglycaemia

Results of randomised controlled trials of tight glycaemic control in hospital inpatients might vary with population and disease state. Individualised therapy for different hospital inpatient populations and identification of patients at risk of hyperglycaemia might be needed. One risk factor that has received much attention is the presence of pre-existing diabetes. So-called stress hyperglycaemia is usually defined as hyperglycaemia resolving spontaneously after dissipation of acute illness. The term generally refers to patients without known diabetes, although patients with diabetes might also develop stress hyperglycaemia-a fact overlooked in many studies comparing hospital inpatients with or without diabetes. Investigators of several studies have suggested that patients with stress hyperglycaemia are at higher risk of adverse consequences than are those with pre-existing diabetes. We describe classification of stress hyperglycaemia, mechanisms of harm, and management strategies.

Abnormal insulin sensitivity persists up to three years in pediatric patients post-burn

CONTEXT

The acute hypermetabolic response post-burn is associated with insulin resistance and hyperglycemia, significantly contributing to adverse outcome of these patients.

OBJECTIVE

The aim of the study was to examine the persistence of abnormalities of various clinical parameters commonly utilized to assess the degree of insulin resistance in severely burned children for up to 3 yr after the burn injury.

DESIGN, SETTING AND PATIENTS

A total of 194 severely burned pediatric patients, admitted to our institute between 2002 and 2007, were enrolled in this prospective study and compared to a cohort of 95 nonburned, noninjured children.

MAIN OUTCOME MEASURES

Urinary cortisol, epinephrine, and norepinephrine, serum cytokines, and resting energy requirements were determined at admission and 1, 2, 6, 9, 12, 18, 24, and 36 months post-burn. A 75-g oral glucose tolerance test was performed at similar time points; serum glucose, insulin, and C-peptide were measured; and insulin sensitivity indices, such as ISI Matsuda, homeostasis model assessment, quantitative insulin sensitivity check index, and ISI Cederholm, were calculated. Statistical analysis was performed by ANOVA with Bonferroni correction with significance accepted at P < 0.05.

RESULTS

Urinary cortisol and catecholamines, serum IL-7, IL-10, IL-12, macrophage inflammatory protein-1b, monocyte chemoattractant protein-1, and resting energy requirements were significantly increased for up to 36 months post-burn (P < 0.05). Glucose values were significantly augmented for 6 months post-burn (P < 0.05), associated with significant increases in serum C-peptide and insulin that remained significantly increased for 36 months compared to nonburned children (P < 0.05). Insulin sensitivity indices, ISI Matsuda, ISI quantitative insulin sensitivity check index, and homeostasis model assessment were abnormal throughout the whole study period, indicating peripheral and whole body insulin resistance. The insulinogenic index displayed physiological values, indicating normal pancreatic beta-cell function.

CONCLUSIONS

A severe burn is associated with stress-induced insulin resistance that persists not only during the acute phase but also for up to 3 yr post-burn.

Critical care nutrition for feline patients

Nutritional treatment in critical care patients is an important component of the complete treatment plan. Assessment of nutritional status and careful consideration of the disease course will help guide the selection of the most appropriate assisted-feeding method. Enteral nutrition is favored over parenteral nutrition when the gastrointestinal tract is functional. Common routes of enteral feeding include nasoesophageal, esophagostomy, gastrostomy, and jejunostomy feeding tubes. Parenteral nutrition is indicated for patients who cannot tolerate enteral feedings, or are poor anesthetic candidates for proper feeding tube placement. Appropriate diet selection and implementation of proper feeding guidelines and monitoring will aide in limiting complications associated with enteral and/or parenteral feeding.

Emergency treatment of severely burned pediatric patients: current therapeutic strategies

Burn trauma represents a devastating injury and remains as one of the leading causes of mortality and morbidity in children. Effective prevention strategies, advances in therapeutic techniques, based on an improved understanding of fluid resuscitation, appropriate infection control and improved treatment of inhalation injury, enhanced wound coverage, better nutritional regimens, advanced support of the hypermetabolic response to injury and improved glucose control, have significantly improved the clinical outcome of this unique patient population over the past years. This article aims to outline the current and emerging therapeutic strategies for the treatment of severely burned pediatric patients in the emergency department or initial phase of the intensive care unit.

Obesity-induced insulin resistance and hyperglycemia: etiologic factors and molecular mechanisms

Obesity is a major cause of type 2 diabetes, clinically evidenced as hyperglycemia. The altered glucose homeostasis is caused by faulty signal transduction via the insulin signaling proteins, which results in decreased glucose uptake by the muscle, altered lipogenesis, and increased glucose output by the liver. The etiology of this derangement in insulin signaling is related to a chronic inflammatory state, leading to the induction of inducible nitric oxide synthase and release of high levels of nitric oxide and reactive nitrogen species, which together cause posttranslational modifications in the signaling proteins. There are substantial differences in the molecular mechanisms of insulin resistance in muscle versus liver. Hormones and cytokines from adipocytes can enhance or inhibit both glycemic sensing and insulin signaling. The role of the central nervous system in glucose homeostasis also has been established. Multipronged therapies aimed at rectifying obesity-induced anomalies in both central nervous system and peripheral tissues may prove to be beneficial.