Effect of glucose-insulin-potassium infusion on mortality in critical care settings: a systematic review and meta-analysis

High dose insulin therapy for inotropic support during veno-arterial extracorporeal membrane oxygenation decannulation: A case report

RATIONALE

High-dose insulin (HDI) therapy has been used as inotropic support for toxin-induced cardiogenic shock, but literature suggests that it can also be used in non-toxin-induced cardiogenic shock states. Its use has not been reported in veno-arterial extracorporeal membrane oxygenation (VA-ECMO) decannulation.

PATIENT CONCERNS

A 56-year-old male presented with progressive dyspnea and lower extremity edema without any reported toxic ingestion.

DIAGNOSIS

After left heart catheterization, he was diagnosed with acute biventricular nonischemic cardiac failure that ultimately required VA-ECMO support for 8 days, after which decannulation was planned.

INTERVENTIONS

During decannulation, he was initiated on HDI therapy via a 1 U/kg regular insulin bolus with 25 g of dextrose and a 1 U/kg/hr insulin infusion.

OUTCOMES

During the decannulation, he was monitored with transesophageal echocardiography. Initially, left ventricular (LV) ejection fraction (EF) was estimated at 10% to 15%. Transesophageal echocardiography after HDI but prior to decannulation showed LVEF 30% to 40%. Transthoracic echocardiography 3.5 hours after HDI bolus and decannulation revealed normal LV systolic function; LVEF 50% to 55%.

LESSONS

While multiple interventions occurred during decannulation, HDI therapy may have assisted in transitioning off ECMO support, and HDI should be investigated as an adjunctive option in future decannulations and other non-toxin-induced cardiogenic shock states.

Effect of Glucose-Insulin-Potassium Infusion on Hemodynamics in Patients with Septic Shock

BACKGROUND: Glucose-insulin-potassium (GIK) demonstrates a cardioprotective effect by providing metabolic support and anti-inflammatory action, and may be useful in septic myocardial depression. AIM: The aim of this study was to assess role of GIK infusion in improving hemodynamics in patients with septic shock in addition to its role in myocardial protection and preventing occurrence of sepsis-induced myocardial dysfunction and sepsis-induced arrhythmias. METHODS: This study was conducted on 75 patients admitted to the Critical Care Department in Cairo University Hospital with the diagnosis of septic shock during the period from January 2019 to December 2019. Patients were divided into two groups; first group was managed according to the last guidelines of surviving sepsis campaign and was subjected to the GIK infusion protocol while second group was managed following the last guidelines of surviving sepsis campaign only without adding GIK infusion. RESULTS: Patients in the GIK group showed better lactate clearance (50% vs. 46.7%) and less time needed for successful weaning of vasopressors than the control group (3.57±1.16 vs. 3.6±1.45 days) thought not reaching statistical significance. There was no statistically significant difference between both groups regarding development of septic-induced cardiomyopathy (16.7% in the control group vs. 13.3% in the GIK group); however, patients with hypodynamic septic shock showed better improvement in hemodynamic profile in the GIK group. Sepsis-induced arrhythmias occurred more in patients of the control group than in patients of the GIK group with no statistically significant difference between both groups (33.3% vs. 20%, p = 0.243). Few side effects were developed as a result of using GIK infusion protocol. CONCLUSIONS: GIK may help in improving hemodynamics and weaning of vasopressors in patients with refractory septic shock and those with septic induced cardiomyopathy. The use of GIK was well tolerated with minimal adverse reactions.

Glucose-lowering therapy in patients undergoing percutaneous coronary intervention

The number of individuals with diabetes and pre-diabetes is constantly increasing. These conditions are overrepresented in patients undergoing percutaneous coronary intervention and are associated with adverse prognosis. Optimal glycaemic control during an acute coronary syndrome is a relevant factor for the improvement of longer-term outcomes. In addition, the implementation of newer glucose-lowering drugs with proven cardiovascular benefits has a remarkable impact on recurrence of events, hospitalisations for heart failure and mortality. In this narrative review, we outline the current state-of-the art recommendations for glucose-lowering therapy in patients with diabetes undergoing coronary intervention. In addition, we discuss the most recent evidence-based indications for revascularisation in patients with diabetes as well as the targets for glycaemic control post revascularisation. Current treatment goals for concomitant risk factor control are also addressed. Lastly, we acknowledge the presence of knowledge gaps in need of future research.

Tsg101 Is Involved in the Sorting and Re-Distribution of Glucose Transporter-4 to the Sarcolemma Membrane of Cardiac Myocytes

Cardiac cells can adapt to pathological stress-induced energy crisis by shifting from fatty acid oxidation to glycolysis. However, the use of glucose-insulin-potassium (GIK) solution in patients undergoing cardiac surgery does not alleviate ischemia/reperfusion (I/R)-induced energy shortage. This indicates that insulin-mediated translocation of glucose transporter-4 (Glut-4) is impaired in ischemic hearts. Indeed, cardiac myocytes contain two intracellular populations of Glut-4: an insulin-dependent non-endosomal pool (also referred to as Glut-4 storage vesicles, GSVs) and an insulin-independent endosomal pool. Tumor susceptibility gene 101 (Tsg101) has been implicated in the endosomal recycling of membrane proteins. In this study, we aimed to examine whether Tsg101 regulated the sorting and re-distribution of Glut-4 to the sarcolemma membrane of cardiomyocytes under basal and ischemic conditions, using gain- and loss-of-function approaches. Forced overexpression of Tsg101 in mouse hearts and isolated cardiomyocytes could promote Glut-4 re-distribution to the sarcolemma, leading to enhanced glucose entry and adenosine triphosphate (ATP) generation in I/R hearts which in turn, attenuation of I/R-induced cardiac dysfunction. Conversely, knockdown of Tsg101 in cardiac myocytes exhibited opposite effects. Mechanistically, we identified that Tsg101 could interact and co-localize with Glut-4 in the sarcolemma membrane of cardiomyocytes. Our findings define Tsg101 as a novel regulator of cardiac Glut-4 trafficking, which may provide a new therapeutic strategy for the treatment of ischemic heart disease.

High-Dose Insulin for Toxin Induced Cardiogenic Shock: Experience at a New High and Overview of the Evidence

BACKGROUND

High-dose insulin therapy is an effective treatment for cardiogenic shock caused by the overdose of particular medications. Other treatment options are usually of limited benefit. Consensus suggests that early initiation improves efficacy. No ceiling effect has been established at doses in the general range of 0.5-10 units/kg/hour.

CASE REPORT

A 79-year-old man presented in cardiogenic shock after an intentional overdose of numerous cardioactive medications 10 days after experiencing myocardial infarction. A high-dose insulin infusion was commenced. This was titrated up to a maximum of 20 units/kg/hour (1600 units/hour) and sustained for 32 h (61,334 units total). Minimal adverse events were seen despite this exceptional infusion rate (3 episodes of hypoglycemia and 2 episodes of hypokalemia). Concurrent catecholamine support was used, and cardiovascular function was maintained until all support was withdrawn 5 days after admission. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians are pivotal to the successful initiation/up-titration of high-dose insulin therapy. They must balance the potential for treatment failure with other treatment options, mitigate against adverse events in the initial phase of therapy, and coordinate care between other hospital specialties. This case shows that the relative safety and efficacy was extended to an infusion rate of 20 units/kg/hour, the highest recorded in the published literature. This information may help guide treatment of similar cases in the future.

Critical appraisal and systematic review of guidelines for perioperative diabetes management: 2011-2017

PURPOSE

To systematically evaluate the quality, consistency and the evidence support of guidelines for perioperative diabetes management.

METHODS

We retrieved guidelines through systematic search, critically evaluated their quality and compared the recommendations of included guidelines. Five aspects were compared: target level, management of hyper- and hypoglycaemia, frequency of monitoring, management of insulin, and management of oral anti-diabetic drugs (OADs).

RESULTS

Fourteen guidelines met our criteria, and 342 recommendations were extracted, the results of Appraisal of Guidelines for Research and Evaluation II (AGREE II) evaluation showed that none of the mean score in each domain was higher than 50%. On average, most guidelines had only one domain scored above 50%. Most recommendations (78.9%) did not specify their supporting evidence, 71 (20.8%) were formed using grading criteria, none cited systematic review or meta-analysis. Recommendations were inconsistent across different guidelines.

CONCLUSIONS

The existing guidelines about perioperative management of diabetes needs improvement in methodology, as well as the production of evidence with high quality. Evidence-based guidelines are required for the perioperative management of diabetes.

Experience using high-dose glucose-insulin-potassium (GIK) in critically ill patients

PURPOSE

To audit the use of GIK in terms of safety, haemodynamic effects, and impact on catecholamine dosage.

MATERIALS AND METHODS

A retrospective, descriptive, evaluative audit of GIK use within the adult ICU of a London teaching hospital was conducted. Rescue therapy of GIK (up to 1.0Unitsinsulin/kg/h) was administered to improve cardiac function. Outcomes were ICU survival, change in cardiac index (CI) and blood lactate levels, events of hypoglycaemia, hyperglycaemia, hypokalaemia and hyperkalaemia, and discontinuation time of catecholamine inotropes.

RESULTS

Of 85 patients treated with GIK, 13 (15.3%) survived their ICU stay and 9 (10.5%) were discharged home. In patients surviving until 72h, a trend of improved CI and lactate levels was seen, often with reductions in catecholamine dosing. Inotropes were discontinued in 35 (54%) patients. Severe hypoglycaemia (<2mmol/l), hyperglycaemia (>20mmol/l), hypokalaemia (<2.5mmol/l) and hyperkalaemia (>7mmol/l) during GIK affected 1, 6, 8 and 1 patients, respectively. These abnormalities were quickly identified. No measurable harm was noted.

CONCLUSIONS

High-dose GIK can be safely used in critically ill patients, though blood glucose and potassium levels must be monitored frequently. GIK was associated with improved CI and blood lactate levels. Impact on survival requires prospective evaluation.

Cardiac complications in thalassemia major

The myocardium is particularly susceptible to complications from iron loading in thalassemia major. In the first years of life, severe anemia leads to high-output cardiac failure and death if not treated. The necessary supportive blood transfusions create loading of iron that cannot be naturally excreted, and this iron accumulates within tissues, including the heart. Free unbound iron catalyzes the formation of toxic hydroxyl radicals, which damage cells and cause cardiac dysfunction. Significant cardiac siderosis may present by the age of 10 and may lead to acute clinical heart failure, which must be treated urgently. Atrial fibrillation is the most frequently encountered iron-related arrhythmia. Iron chelation is effective at removing iron from the myocardium, at the expense of side effects that hamper compliance to therapy. Monitoring of myocardial iron content is mandatory for clinical management of cardiac risk. T2* cardiac magnetic resonance measures myocardial iron and is the strongest biomarker for prediction of heart failure and arrhythmic events. It has been calibrated to human myocardial tissue iron concentration and is highly reproducible across all magnetic resonance scanner vendors. As survival and patient age increases, endothelial dysfunction and diabetes may become new factors in the cardiovascular health of thalassemia patients. Promising new imaging technology and therapies could ameliorate the long-term prognosis.

Guidelines for Perioperative Management of the Diabetic Patient

Management of glycemic levels in the perioperative setting is critical, especially in diabetic patients. The effects of surgical stress and anesthesia have unique effects on blood glucose levels, which should be taken into consideration to maintain optimum glycemic control. Each stage of surgery presents unique challenges in keeping glucose levels within target range. Additionally, there are special operative conditions that require distinctive glucose management protocols. Interestingly, the literature still does not report a consensus perioperative glucose management strategy for diabetic patients. We hope to outline the most important factors required in formulating a perioperative diabetic regimen, while still allowing for specific adjustments using prudent clinical judgment. Overall, through careful glycemic management in perioperative patients, we may reduce morbidity and mortality and improve surgical outcomes.

Therapeutic strategies for high-dose vasopressor-dependent shock

There is no consensual definition of refractory shock. The use of more than 0.5 mcg/kg/min of norepinephrine or epinephrine to maintain target blood pressure is often used in clinical trials as a threshold. Nearly 6% of critically ill patients will develop refractory shock, which accounts for 18% of deaths in intensive care unit. Mortality rates are usually greater than 50%. The assessment of fluid responsiveness and cardiac function can help to guide therapy, and inotropes may be used if hypoperfusion signs persist after initial resuscitation. Arginine vasopressin is frequently used in refractory shock, although definite evidence to support this practice is still missing. Its associations with corticosteroids improved outcome in observational studies and are therefore promising alternatives. Other rescue therapies such as terlipressin, methylene blue, and high-volume isovolemic hemofiltration await more evidence before use in routine practice.

Role of insulin in the type 2 diabetes therapy: past, present and future

CONTEXT

Since 2006 a relevant number of therapeutical algorithms for the management of type 2 diabetes have been proposed, generating a lively debate in the scientific community, particularly on the ideal timing for introduction of insulin therapy and on which drug should be preferred as add-on therapy in patients failing to metformin. At the moment, there is no real consensus. The aim of the present review is to summarize established knowledge and areas for debate with respect to insulin therapy in type 2 diabetes.

EVIDENCE ACQUISITION

In type 2 diabetic patients, insulin represents a therapy with a long and well-established history, but, considering the modern insulin therapy, several points must be carefully examined. The role played by the introduction of insulin analogues, the choice of insulin regimens, the ongoing debate on insulin and cancer, the cardiovascular effects of insulin, the role of insulin on β-cell protection and the actual clinical perspective in the treatment of the disease. Nevertheless, still many exciting expectations exist: the new insulin analogues, the technological options, the inhaled and oral insulin and the issue of transplantation.

CONCLUSIONS

Although insulin is the more potent hypoglicemic agent, the availability of a wider spectrum of therapeutic agents, many of which are better tolerated than insulin, has reduced the field of application for insulin treatment; presently, insulin is used only in those who cannot maintain an adequate glycemic control with other drugs. Furthermore, a lively research activity is currently ongoing, in order to make insulin therapy even safer and simpler for patients.

Cardiovascular function and treatment in β-thalassemia major: a consensus statement from the American Heart Association

This aim of this statement is to report an expert consensus on the diagnosis and treatment of cardiac dysfunction in β-thalassemia major (TM). This consensus statement does not cover other hemoglobinopathies, including thalassemia intermedia and sickle cell anemia, in which a different spectrum of cardiovascular complications is typical. There are considerable uncertainties in this field, with a few randomized controlled trials relating to treatment of chronic myocardial siderosis but none relating to treatment of acute heart failure. The principles of diagnosis and treatment of cardiac iron loading in TM are directly relevant to other iron-overload conditions, including in particular Diamond-Blackfan anemia, sideroblastic anemia, and hereditary hemochromatosis. Heart failure is the most common cause of death in TM and primarily results from cardiac iron accumulation. The diagnosis of ventricular dysfunction in TM patients differs from that in nonanemic patients because of the cardiovascular adaptation to chronic anemia in non-cardiac-loaded TM patients, which includes resting tachycardia, low blood pressure, enlarged end-diastolic volume, high ejection fraction, and high cardiac output. Chronic anemia also leads to background symptomatology such as dyspnea, which can mask the clinical diagnosis of cardiac dysfunction. Central to early identification of cardiac iron overload in TM is the estimation of cardiac iron by cardiac T2* magnetic resonance. Cardiac T2* <10 ms is the most important predictor of development of heart failure. Serum ferritin and liver iron concentration are not adequate surrogates for cardiac iron measurement. Assessment of cardiac function by noninvasive techniques can also be valuable clinically, but serial measurements to establish trends are usually required because interpretation of single absolute values is complicated by the abnormal cardiovascular hemodynamics in TM and measurement imprecision. Acute decompensated heart failure is a medical emergency and requires urgent consultation with a center with expertise in its management. The first principle of management of acute heart failure is control of cardiac toxicity related to free iron by urgent commencement of a continuous, uninterrupted infusion of high-dose intravenous deferoxamine, augmented by oral deferiprone. Considerable care is required to not exacerbate cardiovascular problems from overuse of diuretics or inotropes because of the unusual loading conditions in TM. The current knowledge on the efficacy of removal of cardiac iron by the 3 commercially available iron chelators is summarized for cardiac iron overload without overt cardiac dysfunction. Evidence from well-conducted randomized controlled trials shows superior efficacy of deferiprone versus deferoxamine, the superiority of combined deferiprone with deferoxamine versus deferoxamine alone, and the equivalence of deferasirox versus deferoxamine.

Small studies may overestimate the effect sizes in critical care meta-analyses: a meta-epidemiological study

INTRODUCTION

Small-study effects refer to the fact that trials with limited sample sizes are more likely to report larger beneficial effects than large trials. However, this has never been investigated in critical care medicine. Thus, the present study aimed to examine the presence and extent of small-study effects in critical care medicine.

METHODS

Critical care meta-analyses involving randomized controlled trials and reported mortality as an outcome measure were considered eligible for the study. Component trials were classified as large (≥100 patients per arm) and small (<100 patients per arm) according to their sample sizes. Ratio of odds ratio (ROR) was calculated for each meta-analysis and then RORs were combined using a meta-analytic approach. ROR<1 indicated larger beneficial effect in small trials. Small and large trials were compared in methodological qualities including sequence generating, blinding, allocation concealment, intention to treat and sample size calculation.

RESULTS

A total of 27 critical care meta-analyses involving 317 trials were included. Of them, five meta-analyses showed statistically significant RORs <1, and other meta-analyses did not reach a statistical significance. Overall, the pooled ROR was 0.60 (95% CI: 0.53 to 0.68); the heterogeneity was moderate with an I2 of 50.3% (chi-squared = 52.30; P = 0.002). Large trials showed significantly better reporting quality than small trials in terms of sequence generating, allocation concealment, blinding, intention to treat, sample size calculation and incomplete follow-up data.

CONCLUSIONS

Small trials are more likely to report larger beneficial effects than large trials in critical care medicine, which could be partly explained by the lower methodological quality in small trials. Caution should be practiced in the interpretation of meta-analyses involving small trials.

Blood glucose control and coronary heart disease

Epidemiologic data support the hypothesis of a direct and independent relationship between hyperglycemia and cardiovascular disease. The lack of a clear-cut threshold value in diabetic patients, and the persistence of the relationship in nondiabetic population as well, suggest that glycemia is a continuous variable, similarly to other cardiovascular risk factors. Moreover, increased plasma glucose levels contribute to cardiovascular risk by activating multiple atherogenic mechanisms. In spite of evident plausibility for hyperglycemia as a cardiovascular risk factor per se, intervention data remain controversial. Results of recent large-scale intervention trials, such as ACCORD, ADVANCE, and VADT, seem to undermine the concept that tight glycemic control confers some protection against cardiovascular disease in patients with type 2 diabetes, while maintenance of near-normal glycemic control from earlier stage of the disease and during acute coronary events seems to be more beneficial. However, individualized therapies remain the cornerstone of strategies aimed to reduce cardiovascular risk associated to hyperglycemia.

Implementation and evaluation of a nurse-centered computerized potassium regulation protocol in the intensive care unit--a before and after analysis

Background

Potassium disorders can cause major complications and must be avoided in critically ill patients. Regulation of potassium in the intensive care unit (ICU) requires potassium administration with frequent blood potassium measurements and subsequent adjustments of the amount of potassium administrated. The use of a potassium replacement protocol can improve potassium regulation. For safety and efficiency, computerized protocols appear to be superior over paper protocols. The aim of this study was to evaluate if a computerized potassium regulation protocol in the ICU improved potassium regulation.

Methods

In our surgical ICU (12 beds) and cardiothoracic ICU (14 beds) at a tertiary academic center, we implemented a nurse-centered computerized potassium protocol integrated with the pre-existent glucose control program called GRIP (Glucose Regulation in Intensive Care patients). Before implementation of the computerized protocol, potassium replacement was physician-driven. Potassium was delivered continuously either by central venous catheter or by gastric, duodenal or jejunal tube. After every potassium measurement, nurses received a recommendation for the potassium administration rate and the time to the next measurement. In this before-after study we evaluated potassium regulation with GRIP. The attitude of the nursing staff towards potassium regulation with computer support was measured with questionnaires.

Results

The patient cohort consisted of 775 patients before and 1435 after the implementation of computerized potassium control. The number of patients with hypokalemia (<3.5 mmol/L) and hyperkalemia (>5.0 mmol/L) were recorded, as well as the time course of potassium levels after ICU admission. The incidence of hypokalemia and hyperkalemia was calculated. Median potassium-levels were similar in both study periods, but the level of potassium control improved: the incidence of hypokalemia decreased from 2.4% to 1.7% (P < 0.001) and hyperkalemia from 7.4% to 4.8% (P < 0.001). Nurses indicated that they considered computerized potassium control an improvement over previous practice.

Conclusions

Computerized potassium control, integrated with the nurse-centered GRIP program for glucose regulation, is effective and reduces the prevalence of hypo- and hyperkalemia in the ICU compared with physician-driven potassium regulation.

Drugs and pharmaceuticals: management of intoxication and antidotes

The treatment of patients poisoned with drugs and pharmaceuticals can be quite challenging. Diverse exposure circumstances, varied clinical presentations, unique patient-specific factors, and inconsistent diagnostic and therapeutic infrastructure support, coupled with relatively few definitive antidotes, may complicate evaluation and management. The historical approach to poisoned patients (patient arousal, toxin elimination, and toxin identification) has given way to rigorous attention to the fundamental aspects of basic life support--airway management, oxygenation and ventilation, circulatory competence, thermoregulation, and substrate availability. Selected patients may benefit from methods to alter toxin pharmacokinetics to minimize systemic, target organ, or tissue compartment exposure (either by decreasing absorption or increasing elimination). These may include syrup of ipecac, orogastric lavage, activated single- or multi-dose charcoal, whole bowel irrigation, endoscopy and surgery, urinary alkalinization, saline diuresis, or extracorporeal methods (hemodialysis, charcoal hemoperfusion, continuous venovenous hemofiltration, and exchange transfusion). Pharmaceutical adjuncts and antidotes may be useful in toxicant-induced hyperthermias. In the context of analgesic, anti-inflammatory, anticholinergic, anticonvulsant, antihyperglycemic, antimicrobial, antineoplastic, cardiovascular, opioid, or sedative-hypnotic agents overdose, N-acetylcysteine, physostigmine, L-carnitine, dextrose, octreotide, pyridoxine, dexrazoxane, leucovorin, glucarpidase, atropine, calcium, digoxin-specific antibody fragments, glucagon, high-dose insulin euglycemia therapy, lipid emulsion, magnesium, sodium bicarbonate, naloxone, and flumazenil are specifically reviewed. In summary, patients generally benefit from aggressive support of vital functions, careful history and physical examination, specific laboratory analyses, a thoughtful consideration of the risks and benefits of decontamination and enhanced elimination, and the use of specific antidotes where warranted. Data supporting antidotes effectiveness vary considerably. Clinicians are encouraged to utilize consultation with regional poison centers or those with toxicology training to assist with diagnosis, management, and administration of antidotes, particularly in unfamiliar cases.