Hyperglycemic Hyperosmolar State, commonly known as HHS, is a serious and life-threatening metabolic emergency. It occurs predominantly in older adults with type 2 diabetes mellitus. The condition features severely elevated blood glucose levels, extreme fluid loss, and a very high blood concentration, known as hyperosmolarity. Unlike diabetic ketoacidosis, HHS develops gradually over days or even weeks. Many patients present only after confusion, extreme weakness, or lethargy sets in, which often delays vital hospital admission.
A defining feature of HHS is the absence of significant ketoacidosis. The underlying mechanism involves the presence of a small, circulating amount of endogenous insulin. This minimal insulin level is enough to prevent the breakdown of body fats and the subsequent production of ketone bodies by the liver, but it remains entirely insufficient to facilitate glucose entry into the cells. Because fat breakdown does not occur on a massive scale, dangerous acid accumulation is avoided, setting HHS apart from DKA.
HHS rarely occurs without an underlying trigger. In busy hospital wards and clinics across Nigeria, midwives and nurses frequently identify infection as the leading instigator. Pneumonia and urinary tract infections place severe metabolic stress on the body. Other common triggers include:
The clinical picture of HHS is dominated by profound dehydration and neurological impairment. As blood glucose climbs, the kidneys pull massive amounts of water into the urine through osmotic diuresis.
Patients present with dry mucous membranes, poor skin turgor, sunken eyeballs, tachycardia, and low blood pressure. Neurological signs range from confusion and drowsiness to focal seizures or coma. The degree of mental clouding often correlates directly with the severity of the hyperosmolality.
Laboratory investigation confirms the diagnosis of HHS through specific threshold values. Blood glucose levels are typically extremely high, often exceeding 30 mmol/L (600 mg/dL). Effective serum osmolality is severely elevated, usually above 320 mOsm/kg. Serum bicarbonate remains normal or only mildly depressed (>15 mEq/L), and arterial blood pH is above 7.30, confirming the absence of significant acidosis. Blood urea nitrogen and creatinine are almost always elevated due to pre-renal failure from dehydration.
Fluid resuscitation is the single most critical intervention in treating HHS. Because patients have lost liters of water, rapid volume replacement restores tissue perfusion and lowers serum osmolality. Isotonic sodium chloride solution (0.9% normal saline) is infused aggressively in the first hour to support blood pressure. Once blood pressure stabilizes and urine output is established, the fluid is often switched to hypotonic saline (0.45% normal saline) to replace intracellular water deficits safely.
Insulin administration must be managed carefully in HHS. Giving insulin too early, before adequate fluid replacement, can shift water back into cells rapidly and cause vascular collapse as blood pressure plummets. Regular insulin is typically given as a continuous intravenous infusion after initial fluid resuscitation has begun. Potassium levels must also be closely monitored. As insulin drives glucose and potassium back into the cells, serum potassium can drop dangerously, requiring prompt intravenous replacement.
Comprehensive nursing care is vital for patient survival and recovery. The nurse must maintain strict intake and output records, perform hourly neurological checks, and monitor vital signs continuously. Blood glucose must be tested frequently to guide insulin titration. Once the acute crisis resolves, discharge education focuses on preventing recurrence. Patients and their families must learn to recognize early signs of infection, maintain adequate daily fluid intake, and adhere strictly to prescribed diabetes medications.