Management of Severe Hyperglycemia

Initial Assessment and Management

The American Diabetes Association recommends evaluating for signs of diabetic ketoacidosis (DKA) or hyperosmolar hyperglycemic state (HHS) by checking arterial blood gases, electrolytes, renal function, and ketones in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association suggests starting intravenous fluid resuscitation immediately with 0.9% NaCl at a rapid rate (typically 15-20 mL/kg in the first hour) to correct dehydration in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association recommends beginning intravenous regular insulin therapy with an initial bolus of 0.1 units/kg (for adults) followed by continuous infusion at 0.1 units/kg/hour in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association advises monitoring potassium levels closely as hypokalaemia is common (approximately 50% of cases) during treatment and is associated with increased mortality in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2

The American Diabetes Association recommends continuing IV fluids at 1.5 times the 24-hour maintenance requirements (approximately 5 mL/kg/hour) after initial bolus in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association suggests adjusting fluid type based on serum sodium levels - typically using 0.45-0.9% NaCl depending on corrected sodium values in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association advises changing to 5% dextrose with 0.45-0.75% NaCl when blood glucose reaches 250 mg/dL to prevent hypoglycemia while continuing insulin therapy in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2

The American Diabetes Association recommends adding potassium (20-40 mEq/L) to IV fluids once renal function is confirmed and serum potassium is known to be normal or low in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association suggests using a mixture of potassium chloride and potassium phosphate (2/3 KCl and 1/3 KPO₄) for optimal replacement in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The Lancet Diabetes and Endocrinology recommends monitoring electrolytes (particularly potassium) every 2-4 hours during the acute management phase in patients with severe hyperglycemia (blood sugar >500 mg/dL) 1, 2

The Lancet Diabetes and Endocrinology advises checking blood glucose hourly until stable, then every 2-4 hours in patients with severe hyperglycemia (blood sugar >500 mg/dL) 1
The American Diabetes Association recommends monitoring mental status regularly to identify changes that might indicate iatrogenic complications such as cerebral edema in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association suggests monitoring for resolution of ketosis (preferably by direct measurement of β-hydroxybutyrate) in patients with DKA and severe hyperglycemia (blood sugar >500 mg/dL) 2

The Lancet Diabetes and Endocrinology recommends transitioning to subcutaneous insulin once the patient is stable with glucose <250 mg/dL, anion gap normalized, and able to eat in patients with severe hyperglycemia (blood sugar >500 mg/dL) 1, 2
The Lancet Diabetes and Endocrinology advises calculating the total daily insulin requirement based on the IV insulin rate over the previous 6-12 hours in patients with severe hyperglycemia (blood sugar >500 mg/dL) 1
The Lancet Diabetes and Endocrinology suggests administering first dose of subcutaneous insulin 1-2 hours before discontinuing the insulin infusion to prevent rebound hyperglycemia in patients with severe hyperglycemia (blood sugar >500 mg/dL) 1

Diabetes Care recommends considering treatment with a sulfonylurea, GLP-1 receptor agonist, or dual GIP and GLP-1 receptor agonist as an alternative to insulin for patients with Type 2 diabetes and severe hyperglycemia without significant metabolic derangements, though evidence is limited for patients with blood glucose >500 mg/dL 4

The American Diabetes Association advises against relying solely on sliding-scale insulin for management of severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association recommends avoiding failing to monitor and replace potassium, which can lead to life-threatening arrhythmias in patients with severe hyperglycemia (blood sugar >500 mg/dL) 2
The American Diabetes Association suggests avoiding correcting hyperglycemia too rapidly, which can precipitate cerebral edema, particularly in children and young adults with severe hyperglycemia (blood sugar >500 mg/dL) 2
The Lancet Diabetes and Endocrinology advises against discontinuing IV insulin before subcutaneous insulin has had time to take effect in patients with severe hyperglycemia (blood sugar >500 mg/dL) 1