Glucose control in the intensive care unit: a nutrition support perspective

Stress-Induced Hyperglycemia: Consequences and Management

Hyperglycemia during stress is a common occurrence seen in patients admitted to the hospital. It is defined as a blood glucose level above 180mg/dl in patients without pre-existing diabetes. Stress-induced hyperglycemia (SIH) occurs due to an illness that leads to insulin resistance and decreased insulin secretion. Such a mechanism causes elevated blood glucose and produces a complex state to manage with external insulin. This article compiles various studies to explain the development and consequences of SIH in the critically ill that ultimately lead to an increase in mortality while also discussing the dire impact of SIH on certain acute illnesses like myocardial infarction and ischemic stroke. It also evaluates multiple studies to understand the management of SIH with insulin and proper nutritional therapy in the hospitalized patients admitted to the Intensive care unit (ICU) alongside the non-critical care unit. While emphasizing the diverse effects of improper control of SIH in the hospital, this article elucidates and discusses the importance of formulating a discharge plan due to an increased risk of type 2 diabetes in the recovered.

Stress Hyperglycemia and Osteocalcin in COVID-19 Critically Ill Patients on Artificial Nutrition

We aimed to study the possible association of stress hyperglycemia in COVID-19 critically ill patients with prognosis, artificial nutrition, circulating osteocalcin, and other serum markers of inflammation and compare them with non-COVID-19 patients. Fifty-two critical patients at the intensive care unit (ICU), 26 with COVID-19 and 26 non-COVID-19, were included. Glycemic control, delivery of artificial nutrition, serum osteocalcin, total and ICU stays, and mortality were recorded. Patients with COVID-19 had higher ICU stays, were on artificial nutrition for longer (p = 0.004), and needed more frequently insulin infusion therapy (p = 0.022) to control stress hyperglycemia. The need for insulin infusion therapy was associated with higher energy (p = 0.001) and glucose delivered through artificial nutrition (p = 0.040). Those patients with stress hyperglycemia showed higher ICU stays (23 ± 17 vs. 11 ± 13 days, p = 0.007). Serum osteocalcin was a good marker for hyperglycemia, as it inversely correlated with glycemia at admission in the ICU (r = -0.476, p = 0.001) and at days 2 (r = -0.409, p = 0.007) and 3 (r = -0.351, p = 0.049). In conclusion, hyperglycemia in critically ill COVID-19 patients was associated with longer ICU stays. Low circulating osteocalcin was a good marker for stress hyperglycemia.

Effect of Magnesium Loading Dose on Insulin Resistance in Patients With Stress-Induced Hyperglycemia: A Randomized Clinical Trial

OBJECTIVES

There is currently no evidence that whether magnesium supplementation would improve stress-induced hyperglycemia (SIH) in critically ill patients. In this study, effects of magnesium loading dose on insulin resistance (IR) indices were evaluated in critically ill patients without diabetes having SIH.

METHODS

Seventy critically ill patients with SIH were assigned to receive a loading dose of magnesium (7.5 g of magnesium sulfate in 500 mL normal saline as intravenous infusion over an 8-hour period) or placebo. Changes in baseline of serum and intracellular magnesium and serum adiponectin (AD) levels, homeostasis model assessment of IR (HOMA-IR), and HOMA-AD ratio were assessed in this study.

RESULTS

Serum and intracellular magnesium levels increased significantly in patients in the magnesium group (P < .001). At day 3, there were significant differences between the magnesium group and the placebo group in the mean changes from baseline in the HOMA (between-group difference: -0.11; 95% confidence interval [CI]: -0.19 to -0.01; P = .02), the AD (between-group difference: 0.94; 95% CI: 0.41-1.48; P = .04), and the HOMA-AD ratio (between-group difference: -0.03; 95% CI: -0.04 to -0.01; P < .001).

CONCLUSION

In the present study, a single-loading dose of intravenous magnesium improved IR indices in critically ill patients with SIH.

Glucose control in acute brain injury: does it matter?

PURPOSE OF REVIEW

Alterations of blood glucose levels are secondary insults with detrimental consequences for the injured brain. Here, we review various aspects of brain glucose metabolism and analyze the evidence on glycemic control during acute brain injury.

RECENT FINDINGS

An essential component in the overall management of acute brain injury, especially during the acute phase, is maintaining adequate and appropriate control of serum glucose. This is one of the few physiological parameters that is modifiable. Hypoglycemia should be rigorously avoided. However, intensive insulin therapy is associated with unacceptable rates of hypoglycemia and metabolic crisis, and does not necessarily provide benefit. Hyperglycemia is harmful to the injured brain as it compromises microcirculatory blood flow, increases blood-brain barrier permeability, and promotes inflammation. In addition, it triggers osmotic diuresis, hypovolemia, and immunosuppression.

SUMMARY

Glucose is the primary energy substrate for the brain. During injury, the brain increases its needs and is vulnerable to glucose deficit. In these situations, alternative fuel can be lactate, which has potential implications for future research. In this review, various pathophysiological aspects of glucose metabolism during acute brain injury, as well as the risks, causes, and consequences of glucose deficiency or excess, will be discussed.

Effect of vitamin D on stress-induced hyperglycaemia and insulin resistance in critically ill patients

AIM

Effects of vitamin D supplementation on the glycaemic indices and insulin resistance in diabetic and non-diabetic patients were studied. In this study, effects of vitamin D supplementation on stress-induced hyperglycaemia and insulin resistance were evaluated in non-diabetic surgical critically ill patients.

METHODS

Adult surgical patients with stress-induced hyperglycaemia within the first 24 h of admission to the ICU were recruited. The patients randomly assigned to receive either vitamin D or placebo. Patients in the vitamin D group received a single dose of 600,000 IU vitamin D3 as intramuscular injection at time of recruitment. Besides demographic and clinical characteristics of the patients, plasma glucose, insulin, 25(OH) D and adiponectin levels were measured at the time of ICU admission and day 7. Homoeostasis model assessment for insulin resistance (HOMA-IR) and homestasis model assessment adiponectin (HOMA-AD) ratio were considered at the times of assessment.

RESULTS

Comparing with the baseline, plasma 25(OH) D level significantly increased in the subjects who received vitamin D (p = 0.04). Improvement in fasting plasma glucose levels was detected in day 7 of the study compared with the baseline status in both groups. HOMA-IR showed a decrement pattern in vitamin D group (p = 0.09). Fasting plasma adiponectin levels increased significantly in the vitamin D group (p = 0.007), but not in the placebo group (p = 0.38). Finally, changes in HOMA-AD ratio were not significant in the both groups.

CONCLUSION

Vitamin D supplementation showed positive effect on plasma adiponectin level, as a biomarker of insulin sensitivity in surgical critically ill patients with stress-induced hyperglycaemia. However, effects of vitamin D supplementation on HOMA-IR and HOMA-AD as indicators of insulin resistance were not significant.

Steps to consider in the approach and management of critically ill patient with spontaneous intracerebral hemorrhage

Spontaneous intracerebral hemorrhage is a type of stroke associated with poor outcomes. Mortality is elevated, especially in the acute phase. From a pathophysiological point of view the bleeding must traverse different stages dominated by the possibility of re-bleeding, edema, intracranial hypertension, inflammation and neurotoxicity due to blood degradation products, mainly hemoglobin and thrombin. Neurological deterioration and death are common in early hours, so it is a true neurological-neurosurgical emergency. Time is brain so that action should be taken fast and accurately. The most significant prognostic factors are level of consciousness, location, volume and ventricular extension of the bleeding. Nihilism and early withdrawal of active therapy undoubtedly influence the final result. Although there are no proven therapeutic measures, treatment should be individualized and guided preferably by pathophysiology. The multidisciplinary teamwork is essential. Results of recently completed studies have birth to promising new strategies. For correct management it’s important to establish an orderly and systematic strategy based on clinical stabilization, evaluation and establishment of prognosis, avoiding secondary insults and adoption of specific individualized therapies, including hemostatic therapy and intensive control of elevated blood pressure. Uncertainty continues regarding the role of surgery.

Effectiveness, safety and feasibility of an evidence-based insulin infusion protocol targeting moderate glycaemic control in intensive cardiac care units

OBJECTIVES

To assess the effectiveness, safety and feasibility of the revised, simplified nurse-managed version of our insulin infusion protocol, adapted to the new recommended glycaemic target of 140 to 180 mg/dL (Desio Diabetes Diagram i.v. 140-180).

METHODS

All clinical responses to the Desio Diabetes Diagram i.v. 140-180 in use for 3 years were recorded in patients with diabetes or hyperglycaemia admitted to our intensive cardiac care unit. To assess the feasibility, we asked nurses to complete an ad hoc questionnaire anonymously when the new insulin infusion protocol had been in use for 2 years.

RESULTS

From December 2010 to December 2013, 276 patients (173 men, median age 75 years) were treated according to the Desio Diabetes Diagram i.v. 140-180. The median time to reach glycaemic target was 4 h (Q1-Q3 2-8) in 128 patients with blood glucose >180 mg/dL and 2 h (Q1-Q3 1-4) in 82 patients with blood glucose <140 mg/dL. Once the target had been reached, insulin infusion was maintained for a median of 38 h (Q1-Q3 24-48) with blood glucose between 140 and 180 mg/dL for 58.3% of the infusion time. Over a total of 11,863 h of infusion, seven blood glucose <70 mg/dL occurred. The Desio Diabetes Diagram i.v. 140-180 protocol was considered easy to use by 93% of nurses.

CONCLUSIONS

The Desio Diabetes Diagram i.v. 140-180 protocol, fully managed by nurses, with insulin and glucose intravenous infusion proved effective, safe and feasible in maintaining blood glucose between 140 and 180 mg/dL in patients with diabetes or hyperglycaemia admitted to the intensive cardiac care unit for acute cardiac events.

Perioperative glucose control in neurosurgical patients

Many neurosurgery patients may have unrecognized diabetes or may develop stress-related hyperglycemia in the perioperative period. Diabetes patients have a higher perioperative risk of complications and have longer hospital stays than individuals without diabetes. Maintenance of euglycemia using intensive insulin therapy (IIT) continues to be investigated as a therapeutic tool to decrease morbidity and mortality associated with derangements in glucose metabolism due to surgery. Suboptimal perioperative glucose control may contribute to increased morbidity, mortality, and aggravate concomitant illnesses. The challenge is to minimize the effects of metabolic derangements on surgical outcomes, reduce blood glucose excursions, and prevent hypoglycemia. Differences in cerebral versus systemic glucose metabolism, time course of cerebral response to injury, and heterogeneity of pathophysiology in the neurosurgical patient populations are important to consider in evaluating the risks and benefits of IIT. While extremes of glucose levels are to be avoided, there are little data to support an optimal blood glucose level or recommend a specific use of IIT for euglycemia maintenance in the perioperative management of neurosurgical patients. Individualized treatment should be based on the local level of blood glucose control, outpatient treatment regimen, presence of complications, nature of the surgical procedure, and type of anesthesia administered.