What is the treatment for Hyperosmolar Hyperglycemic State (HHS)?

Treatment of Hyperosmolar Hyperglycemic State (HHS)

Patients with suspected HHS should be immediately evaluated and treated in the inpatient setting due to greater volume depletion and typically being triggered by acute illness. 1

Initial Assessment and Management

• HHS is characterized by blood glucose >600 mg/dL, arterial pH >7.3, bicarbonate >15 mEq/L, effective serum osmolality >320 mOsm/kg, and altered mental status or severe dehydration 2
• HHS typically develops over days to a week (compared to hours for DKA) and commonly presents with altered mental status 1
• Total body water deficit in HHS is typically 9 liters (approximately 100-200 mL/kg), which is greater than in DKA (6 liters) 3, 2

Fluid Resuscitation

• Begin with isotonic saline (0.9% NaCl) at 15-20 mL/kg/hr to restore circulatory volume and tissue perfusion 3, 4
• Fluid replacement alone will cause a fall in blood glucose level 5
• Aim to correct estimated fluid deficits within the first 24 hours 3, 4
• Monitor serum osmolality regularly and aim to reduce it by 3-8 mOsm/kg/h to prevent cerebral edema 3, 5

Insulin Therapy

• Withhold insulin until blood glucose is no longer falling with IV fluids alone, unless ketonaemia is present 3, 5
• When insulin is required, administer an intravenous bolus of regular insulin at 0.15 U/kg body weight, followed by continuous infusion at 0.1 U/kg/hr 3, 4
• When blood glucose reaches 250-300 mg/dL, add dextrose (5% or 10%) to IV fluids while continuing insulin infusion at a reduced rate 3, 2

Electrolyte Management

• Monitor serum potassium levels every 2-4 hours as insulin therapy can cause hypokalemia 3, 4
• Begin potassium replacement when serum levels fall below 5.2 mEq/L, provided the patient has adequate urine output 3
• Potassium deficits are typically greater in HHS (5-15 mEq/kg) compared to DKA (3-5 mEq/kg) 2

Monitoring and Transition to Subcutaneous Insulin

• Check blood glucose every 1-2 hours until stable 3, 4
• Monitor serum electrolytes, glucose, blood urea nitrogen, and creatinine every 2-4 hours 2
• Administer basal insulin 2-4 hours before stopping IV insulin to prevent rebound hyperglycemia 1, 2
• Recent studies show that administering a low dose of basal insulin analog in addition to intravenous insulin infusion may prevent rebound hyperglycemia 1

Treatment of Precipitating Factors

• Identify and treat underlying causes such as infection, medication non-compliance, or new-onset diabetes 3, 6
• Common precipitants include sepsis, myocardial infarction, stroke, and other acute illnesses 1, 6

Resolution Criteria

• HHS resolution criteria include: osmolality <300 mOsm/kg, hypovolemia corrected (urine output ≥0.5 mL/kg/h), cognitive status returned to pre-morbid state, and blood glucose <15 mmol/L 4

Common Pitfalls to Avoid

• Early use of insulin before adequate fluid resuscitation may be detrimental 5
• Rapid changes in osmolality during treatment may precipitate cerebral edema or central pontine myelinolysis 3, 5
• Inadequate fluid resuscitation and electrolyte replacement can worsen outcomes 2, 6