Dextrose Metabolism and Utilization

Primary Metabolic Functions

Dextrose serves as metabolic fuel for muscle, liver, heart, kidneys, and gut, while functioning as the obligate energy source for brain, renal medulla, and erythrocytes, according to the Clinical Nutrition guideline society 1
Glucose is utilized by all cells and represents the main carbohydrate reaching peripheral tissues from normal dietary intake, as stated by the Clinical Nutrition guideline society 1
During fetal life, approximately 5 mg/kg per minute (7 g/kg per day) of glucose crosses the placenta, establishing glucose as the main carbohydrate utilized during development, as reported by the Clinical Nutrition guideline society 1

Glucose metabolism is highly modified during acute critical illness in neonates and children, with protein catabolism remaining unchanged despite increasing glucose intake, according to the Clinical Nutrition guideline society 1
Glucose metabolism is influenced by age, acute illness, nutritional state, and concomitant provision of other macronutrients, requiring individualized dosing strategies, as stated by the Clinical Nutrition guideline society 1

Dextrose is rapidly metabolized upon infusion, which is why osmolarity calculations for dextrose-containing solutions typically exclude the dextrose component, as reported by the Pediatrics guideline society 2

In patients with acute ischemic stroke, 5 % dextrose solutions become hypotonic after glucose metabolism and shift markedly into intracellular compartments, which may worsen cerebral edema; therefore, isotonic fluids are preferred in this setting. 3
For rapid correction of severe hypoglycemia, a bolus of 25 mL of 50 % dextrose delivers approximately 12.5 g of glucose, providing an immediate substrate for brain metabolism. 3

Critically ill individuals frequently develop hyperglycemia even when receiving normal or reduced glucose infusion rates, reflecting altered hepatic glucose production and stress‑related metabolic dysregulation. 4
Acute metabolic stress in critical illness induces insulin resistance, limiting cellular glucose uptake despite adequate or elevated plasma glucose concentrations. 4
Because glucose is the preferred energy substrate during emergency metabolic states, dextrose is considered the physiologic choice for acute metabolic support in critically ill patients. 4