endocrine and metabolic disorders
Hyperosmolar Hyperglycemic State (HHS)
Introduction
Hyperosmolar hyperglycemic state is a metabolic complication of diabetes mellitus characterized by severe hyperglycemia, extreme dehydration, hyperosmolar plasma, and altered consciousness. It most often occurs in type 2 diabetes, often in the setting of physiologic stress. Hyperosmolar hyperglycemic state is diagnosed by severe hyperglycemia and plasma hyperosmolality and absence of significant ketosis. Treatment is IV saline solution andinsulin. Complications include coma, seizures, and death. (See also Diabetes Mellitus (DM) and Hyperosmolar hyperglycemic state (previously referred to as hyperglycemic hyperosmolar nonketotic coma [HHNK] and nonketotic hyperosmolar syndrome [NKHS]) is a complication of type 2 diabetes mellitus and has an estimated mortality rate of up to 20%, which is significantly higher than the mortality for Diabetic Ketoacidosis (DKA) (currently < 1%). It usually develops after a period of symptomatic hyperglycemia in which fluid intake is inadequate to prevent extreme dehydration due to the hyperglycemia-induced osmotic diuresis. Precipitating factorsinclude Acute infections and other medical conditions Medications that impair glucose tolerance (glucocorticoids) or increase fluid loss (diuretics) Nonadherence to diabetes treatment Serum ketones are not present because the amount ofinsulinpresent in most patients with type 2 diabetes is adequate to suppress ketogenesis. Because symptoms of acidosis are not present, most patients endure a significantly longer period of osmotic diuresis (high solute concentrations from glucose in the renal tubules, leading to excess water loss). This causes more severe dehydration before presentation, and thus plasma glucose (>600 mg/dL [>33.3 mmol/L]) and osmolality (>320 mOsm/L) are typically much higher than in diabetic ketoacidosis. 