What are the Hyperosmolar Hyperglycemic State (HHS) criteria and management?

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From the Guidelines

Hyperosmolar Hyperglycemic State (HHS) is diagnosed when a patient has severe hyperglycemia (blood glucose >600 mg/dL), hyperosmolality, and significant dehydration without significant ketoacidosis, and management begins with aggressive fluid resuscitation and insulin therapy, as outlined in the most recent guidelines 1. The diagnostic criteria for HHS include:

  • Blood glucose >600 mg/dL
  • Venous pH >7.3
  • Bicarbonate >15 mEq/l
  • Altered mental status or severe dehydration Management of HHS involves:
  • Aggressive fluid resuscitation using isotonic saline (0.9% NaCl) at 15-20 mL/kg/hour for the first hour, followed by 4-14 mL/kg/hour depending on hemodynamic status
  • Insulin therapy with an IV bolus of regular insulin at 0.1 units/kg, followed by continuous infusion at 0.1 units/kg/hour, titrating to reduce glucose by 50-70 mg/dL/hour
  • Potassium replacement when levels fall below 5.2 mEq/L, typically adding 20-30 mEq of potassium to each liter of IV fluid once urine output is established
  • Phosphate replacement may be needed if levels are <1 mg/dL
  • Identification and treatment of underlying causes such as infection, myocardial infarction, stroke, or medication non-adherence The most recent guidelines 1 emphasize the importance of individualizing treatment based on a careful clinical and laboratory assessment, and highlight the need for prompt recognition and aggressive management of HHS to reduce morbidity and mortality. Key considerations in the management of HHS include:
  • Restoration of circulatory volume and tissue perfusion
  • Resolution of hyperglycemia
  • Correction of electrolyte imbalance and ketosis
  • Treatment of any correctable underlying cause of HHS
  • Transition from intravenous to subcutaneous insulin requires administration of basal insulin 2–4 h prior to the intravenous insulin being stopped to prevent recurrence of ketoacidosis and rebound hyperglycemia 1.

From the Research

Hyperosmolar Hyperglycemic State (HHS) Criteria

  • HHS is a life-threatening emergency characterized by marked elevation of blood glucose, hyperosmolarity, and little or no ketosis 2, 3, 4
  • Clinical features of HHS include: + Marked hypovolaemia + Osmolality ≥320 mOsm/kg + Marked hyperglycaemia ≥30 mmol/L + Without significant ketonaemia (≤3.0 mmol/L) + Without significant acidosis (pH >7.3) and bicarbonate ≥15 mmol/L 4
  • Precipitating causes of HHS include underlying infections, certain medications, nonadherence to therapy, undiagnosed diabetes mellitus, substance abuse, and coexisting disease 2, 3, 5

HHS Management

  • Treatment begins with intensive monitoring of the patient and laboratory values, especially glucose, sodium, and potassium levels 2, 3, 6
  • Vigorous correction of dehydration is critical, requiring an average of 9 L of 0.9% saline over 48 hours in adults 2, 3
  • Potassium replacement should begin after urine output is established 2, 3
  • Insulin should be given as an initial bolus of 0.1 units of intravenous insulin per kg of body weight, followed by a continuous infusion of 0.1 units per kg per hour until the blood glucose level decreases below 300 mg per dL 3
  • Identification and treatment of underlying and precipitating causes are necessary 2, 3, 4
  • Aims of therapy include: + Improve clinical status/replace fluid losses by 24 h + Gradual decline in osmolality (3.0-8.0 mOsm/kg/h to minimise the risk of neurological complications) + Blood glucose 10-15 mmol/L in the first 24 h + Prevent hypoglycaemia/hypokalaemia and prevent harm (VTE, osmotic demyelination, fluid overload, foot ulceration) 4
  • HHS resolution criteria are: + Osmolality <300 mOsm/kg + Hypovolaemia corrected (urine output ≥0.5 ml/kg/h) + Cognitive status returned to pre-morbid state + Blood glucose <15 mmol/L 4

References

Research

Hyperosmolar hyperglycemic state.

American family physician, 2005

Research

Hyperosmolar Hyperglycemic State.

American family physician, 2017

Research

[Hyperosmolar hyperglycemic state].

Vnitrni lekarstvi, 2015

Research

Management of hyperosmolar hyperglycaemic state in adults with diabetes.

Diabetic medicine : a journal of the British Diabetic Association, 2015

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.