This study seeks to measure the treatment effect of glucose-insulin-potassium (GIK) infusion on mortality in critically ill patients. A systematic review of randomized controlled trials is conducted, comparing GIK treatment with standard care or placebo in critically ill adult patients. The primary outcome variable is mortality. Two authors independently extract data and assess study quality. The primary analysis is based on the random effects model to produce pooled odds ratios (ORs) with 95% confidence intervals (CIs). The search yields 1720 potential publications; 23 studies are included in the final analysis, providing a sample of 22 525 patients. The combined results demonstrate no heterogeneity (P = .57, I 2 = 0%) and no effect on mortality (OR = 1.02; 95% CI, 0.93-1.11) with GIK treatment. No experimental studies of shock or sepsis populations are identified. This meta-analysis finds that there is no mortality benefit to GIK infusion in critically ill patients; however, study populations are limited to acute myocardial infarction and cardiovascular surgery patients. No studies are identified using GIK in patients with septic shock or other forms of circulatory shock, providing an absence of evidence regarding the effect of GIK as a therapy in patients with shock.
KeywordsClinical research; critical care; emergency medicine; clinical trials; anesthesiology Infusion of a glucose-insulin-potassium (GIK) solution was first proposed in the 1960s as treatment for acute myocardial infarction (AMI) with the intention of providing electrical stability to the myocardium. 1 The proposed mechanisms of action of GIK therapy in cardiovascular disease include suppression of circulating levels and myocardial uptake of free fatty acids, which are toxic to ischemic myocardium; improvement in the efficiency of myocardial energy production through the provision of exogenous glucose; and stabilization of intracellular potassium, which may be depleted during times of myocardial ischemia. 2,3 Since the sentinel report, numerous randomized controlled trials have been performed using GIK. Pooled data have suggested morbidity and mortality benefits associated with GIK therapy in cardiothoracic surgery 4 and AMI 3 populations. The largest GIK study performed in AMI patients to date failed to find similar benefits. 2 Thus, there remain significant conflicting evidence and debate regarding the utility of GIK infusion in various patient populations. Extensive preclinical rationales support the use of GIK as an inotropic and metabolic therapy in several critical illnesses. The heart develops insulin resistance in shock and sepsis, and insulin-euglycemia produces a potent inotropic effect on the left ventricle. 5,6 Sepsis can lead to excessive phosphorylation of the pyruvate dehydrogenase complex, thus impairing net carbohydrate oxidation in skeletal and heart muscle. 7-9 Deficits in carbohydrate oxidation can be expected to be worsened by the effect of diabetes mellitus, a common comorbidity in humans. 10 Insulin reactivates th...