From the Guidelines
HHS stands for Hyperosmolar Hyperglycemic State, a serious diabetic emergency characterized by extremely high blood sugar levels, severe dehydration, and altered mental status without significant ketoacidosis. This condition occurs predominantly in older adults with type 2 diabetes. The diagnostic criteria for HHS include blood glucose levels typically above 600 mg/dL, severe dehydration, and altered mental status without significant ketoacidosis, as noted in studies such as 1 and 1.
Key Characteristics of HHS
- Extremely high blood sugar levels (typically above 600 mg/dL)
- Severe dehydration
- Altered mental status without significant ketoacidosis
- Occurs predominantly in older adults with type 2 diabetes
Treatment and Management
Treatment requires immediate hospitalization for aggressive fluid replacement with normal saline, insulin therapy, and electrolyte management, particularly potassium, as outlined in 1 and 1. The underlying cause must be identified and treated, which often includes infection, medication non-compliance, or other acute illnesses.
Prevention
Prevention involves regular blood glucose monitoring, medication adherence, adequate hydration, and prompt medical attention during illness. The condition develops gradually over days to weeks as profound hyperglycemia leads to osmotic diuresis, resulting in severe dehydration and electrolyte imbalances that ultimately affect brain function, as discussed in 1 and 1. HHS has a higher mortality rate than diabetic ketoacidosis, approaching 10-20%, highlighting the importance of prompt and effective treatment, as noted in 1 and 1.
From the Research
Definition of HHS
- Hyperosmolar Hyperglycemic State (HHS) is a life-threatening emergency characterized by marked elevation of blood glucose and hyperosmolarity with little or no ketosis 2.
- It is a medical emergency associated with high mortality, affecting those with pre-existing or new type 2 diabetes mellitus, and increasingly affecting children and younger adults 3.
- HHS is often triggered by an underlying illness, most commonly infection, but may also be triggered by stroke, acute coronary syndrome, and other acute illnesses 4.
Clinical Features of HHS
- 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 3.
- Profound dehydration and neurologic symptoms ranging from lethargy to coma 2.
- Serum osmolality greater than 320 mOsm/kg, lack of metabolic acidosis, and minimal to no presence of ketones 4.
Treatment of HHS
- Intensive monitoring of the patient and laboratory values, especially glucose, sodium, and potassium levels 2.
- Vigorous correction of dehydration, requiring an average of 9 L of 0.9% saline over 48 hours in adults 2.
- Intravenous insulin infusion, with 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 2.
- Identification and treatment of underlying and precipitating causes are necessary 2, 3, 4.
- Aims of therapy include improving clinical status, replacing fluid losses, gradual decline in osmolality, and preventing hypoglycaemia and hypokalaemia 3.