Norepinephrine's Impact on Blood Glucose Levels

Primary Metabolic Mechanisms

Alpha-adrenergic receptor stimulation directly reduces insulin release from pancreatic B cells, creating a state of relative insulin deficiency in critically ill patients, according to the European Society of Intensive Care Medicine 1
Beta-adrenergic receptor stimulation in the liver increases glucose production and glycogen breakdown via cyclic AMP formation, contributing to hyperglycemia in critically ill patients, as recommended by the American College of Clinical Endocrinologists 1
Beta-adrenergic stimulation activates glycogenolysis and lactate production in skeletal muscle due to the absence of glucose-6-phosphatase, as stated by the European Society of Intensive Care Medicine 1

Blood glucose should be monitored closely when initiating or titrating norepinephrine, with a target blood glucose of 90-150 mg/dL (5-8 mM) in critically ill patients receiving vasopressors, as recommended by the American Society for Parenteral and Enteral Nutrition 4
Anticipate increased insulin requirements when starting norepinephrine, particularly in diabetic patients, according to the European Society of Intensive Care Medicine 1, 4
Avoid aggressive glucose targets below 180 mg/dL in critically ill patients, as intensive control increases hypoglycemia risk without mortality benefit, as stated by the American College of Physicians 5
Minimize glycemic variability, which is more harmful than moderate hyperglycemia, as recommended by the American Society for Parenteral and Enteral Nutrition 4
Do not extrapolate tight glucose control data from ICU patients to general ward patients, as evidence quality is low outside critical care settings, according to the American College of Physicians 5