What are the laboratory findings in Hyperosmolar Hyperglycemic State (HHS)?

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From the Guidelines

Hyperosmolar Hyperglycemic State (HHS) is characterized by laboratory findings of severe hyperglycemia, elevated serum osmolality, minimal or absent ketosis, and profound dehydration, as evidenced by elevated BUN and creatinine levels. The diagnostic criteria for HHS, as outlined in the study by 1, include blood glucose exceeding 600 mg/dl, venous pH 7.3, bicarbonate 15 mEq/l, and altered mental status or severe dehydration. Key laboratory findings in HHS include:

  • Severe hyperglycemia with blood glucose typically exceeding 600 mg/dL
  • Elevated serum osmolality, usually greater than 320 mOsm/kg
  • Minimal or absent ketosis with serum ketones being negative or slightly positive
  • Profound dehydration with elevated BUN and creatinine levels indicating prerenal azotemia
  • Electrolyte abnormalities, including hypophosphatemia, hypomagnesemia, and occasionally hypocalcemia
  • Arterial blood gases typically showing absent or mild metabolic acidosis with pH usually above 7.30
  • Leukocytosis, which can be stress-induced or indicate underlying infection, as seen in complete blood count results
  • Urinalysis showing glucosuria but minimal or no ketonuria, as noted in the study by 1.

The management of HHS involves prompt recognition and treatment of dehydration, electrolyte imbalances, and hyperglycemia, as outlined in the protocol for the management of pediatric patients with DKA or HHS by 1. The initial assessment should include measurement of blood glucose, venous blood gases, electrolytes, blood urea nitrogen, creatinine, calcium, phosphorous, and urine analysis, as recommended by 1.

From the Research

Laboratory Findings in Hyperosmolar Hyperglycemic State (HHS)

The laboratory findings in HHS include:

  • Elevated glucose levels, typically ≥30 mmol/L 2
  • Elevated serum osmolality, typically ≥320 mOsm/kg 2, 3
  • Minimal or absent ketones, typically ≤3.0 mmol/L 2
  • Mild acidosis, with a pH >7.3 and bicarbonate ≥15 mmol/L 2
  • Dehydration, with significant depletion of both intracellular and extracellular fluid volumes 4
  • Electrolyte imbalances, including potassium depletion 4
  • Hyperglycemia, with plasma glucose > 600 mg/dl 3
  • Venous pH > 7.25, sodium bicarbonate > 15 mmol/l, and slight ketonuria 3
  • Plasma osmolality > 320 mOsm/kg 3
  • Impairment of consciousness, including aggression, unconsciousness, and convulsions 3

Key Laboratory Parameters

Some key laboratory parameters to monitor in HHS include:

  • Blood glucose levels 5, 2, 6, 3
  • Serum osmolality 2, 3
  • Electrolyte levels, including sodium, potassium, and bicarbonate 2, 4
  • Venous pH and pCO2 3
  • Base excess and HCO3 levels 3
  • Plasma osmolarity 3

Diagnostic Criteria

The diagnostic criteria for HHS include:

  • Plasma glucose > 600 mg/dl 3
  • Venous pH > 7.25 3
  • Sodium bicarbonate > 15 mmol/l 3
  • Slight ketonuria 3
  • Plasma osmolality > 320 mOsm/kg 3
  • Impairment of consciousness, including aggression, unconsciousness, and convulsions 3

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.

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