Glucose-insulin-potassium infusion in sepsis and septic shock: no hard evidence yet

Hyperglycemia, Insulin, and Insulin Resistance in Sepsis

Critically ill patients frequently have hyperglycemia. This event may reflect severe stress with an imbalance between anabolic hormones and catabolic hormones. Alternatively, it may reflect alterations in either insulin levels or insulin function. Insulin is a pleiotropic hormone with multiple important metabolic effects. In patients with sepsis, insulin levels are increased but insulin sensitivity is decreased. However, there is variability in insulin sensitivity, and this creates variability in glucose levels and insulin requirements and increases the frequency of hypo- and hyperglycemia. The factors that influence insulin sensitivity are complex and include inhibition of tyrosine kinase activity of the beta subunit, increased proteolytic activity resulting in loss of receptors from the plasma membrane, and possibly the transfer of insulin receptors into the nucleus where they bind to gene promoters. Better understanding of the role of insulin in critically ill patients requires prospective studies measuring insulin levels in various patient groups and the development of a simple measure of insulin sensitivity.

Sepsis in diabetes: A bad duo

Increasing incidence of morbidity and mortality of diabetic subjects due to infection necessitates the understanding of its patho-biology and further remedial measures for its prevention and treatment. The increased incidence of infection is because of systemic illness that has compromising effects on multiple organs including the nervous, vascular, musculoskeletal, and immunologic systems of the diabetic patients. Many factors contribute to this condition including hyperglycemia, insulin deficiency, ischemia and impaired immunity. Sepsis, as a separate entity, lead to destruction of cytokine network that can be fatal. Compromised defense mechanisms due to sepsis and cytokine dysregulation in diabetic patients make the situation worse. Early identification of local infection by applying advanced molecular tools, appropriate selection of antibiotics, intensive wound management, control of glycemic status and supportive treatment can reduce the rate of morbidity and mortality due to sepsis in patients with diabetes.

Hyperglycemia and Mortality in Elderly Patients with Staphylococcus aureus Bacteremia

OBJECTIVE

To investigate the association between hyperglycemia and in-hospital mortality in elderly patients with Staphylococcus aureus bacteremia (SAB).

METHODS

We reviewed the medical records of 135 elderly patients with SAB admitted to two tertiary medical centers from January 2003 until December 2004. Patients were stratified into two groups: those with a 7-day post-SAB mean blood glucose < 170 mg/dL and those with a 7-day post-SAB mean blood glucose > or = 170 mg/dL. A stepwise logistic regression analysis was performed to determine whether the degree of hyperglycemia was a significant predictor of mortality.

RESULTS

Seventy-four (54.8%) patients had methicillin-resistant Staphylococcus aureus bacteremia. During the follow-up period from admission until discharge, 36 (26.7%) patients died. Twenty-one (21.4%) of 98 patients with a 7-day post-SAB mean blood glucose < 170 mg/dL died, while 15 (40.5%) of 37 patients with a 7-day post-SAB mean blood glucose > or = 170 mg/dL expired. Multivariate analysis identified 3 independent determinants of death: Simplified Acute Physiology Score (SAPS) score at onset of SAB > 45 (OR 5.3, 95% CI {1.8, 15.5}, P = 0.002), a 7-day post-SAB mean blood glucose > or = 170 mg/dL (OR 3.3, 95% CI {1.2, 9.2}, P = 0.03), and altered mental status at the onset of SAB (OR 7.8, 95% CI {2.5, 23.9}, P = 0.0003).

CONCLUSIONS

Hyperglycemia is an important marker of increased mortality among hospitalized elderly patients with SAB.

The significance of glucose, insulin and potassium for immunology and oncology: a new model of immunity

Background

A recent development in critical care medicine makes it urgent that research into the effect of hormones on immunity be pursued aggressively. Studies have demonstrated a large reduction in mortality as a result of infusion with glucose, insulin and potassium. Our work in the oncology setting has led us to propose that the principal reason for such an effect is that GIK stimulates lymphocytes to proliferate and attack pathogens, sparing the patient the stress of infection. That suggestion is based on a new model of immunity that describes the effect of hormones on lymphocytes. We hypothesized that the application of glucose, insulin, thyroid and potassium would awaken inert tumor infiltrating lymphocytes to destroy the tumor.

Methods

The antitumor effect of a thyroxine, glucose, insulin, and potassium (TGIK) combination was studied in a series of controlled experiments in murine models of tumor progression to assess the biologic activity of the formulation, the effect of route of administration, the effect on tumor type, and the requirement for insulin in the TGIK formulation.

Results

Melanoma and colon tumors inoculated with TGIK were significantly reduced in size or retarded in growth compared to controls injected with saline. I.P. and I.M. injections showed that the formulation had no effect systemically at the doses administered.

Conclusion

We conclude that TGIK has anti-tumor activity when administered intratumorally, probably by stimulating lymphocytes to attack tumors. This is similar to the effect of GIK on reducing sepsis in critical care patients. We suggest that when GIK is administered exogenously, it restores immune competence to the critically ill or cancer patient and causes destruction of pathogens or tumors, while endogenous resources are devoted to repair. This implies that hormonal therapy may be useful in treating various other pathologies involving immune suppression, as well as malignancies. We also propose research that could bring resolution of the controversy over mechanism and point the way to new therapeutic strategies for numerous diseases including chronic infections and auto-immune diseases.