Hyperosmolar hyperglycemic state

Background

• Prototypical patient is elderly with uncontrolled type II DM without adequate access to H2O
• Occurs due to 3 factors:
  • Insulin resistance or deficiency
  • Increased hepatic gluconeogenesis and glycogenolysis
  • Osmotic diuresis and dehydration followed by impaired renal excretion of glucose
    • May result in TBW losses of 8-12L
• Ketosis usually absent (may be mild)
• Cerebral edema is uncommon complication (case reports)
• Estimated mortality 10-20%, usually due to underlying precipitant
  • In contrast to DKA, in which mortality is 1-5%
  • Incidence of HHS < 1% of hospital admissions of patients with diabetes

Precipitants

• Pneumonia (Main)
• Urinary tract infection
• Medication non-adherence
• Cocaine intoxication
• Meds: Beta-blockers, diuretics
• GI bleed
• Pancreatitis
• Heat related emergencies
• Acute coronary syndrome
• Stroke

Clinical Features

• Dehydration
  • Hypotension
• Seizure (15% of patients)
• Altered mental status
• Lethargy/coma

Differential Diagnosis

Hyperglycemia

• Physiologic stress response (rarely causes glucose >200 mg/dL)
• Diabetes mellitus (main)
  • Nonketotic hyperglycemia
  • Hyperosmolar hyperglycemic state (HHS/HONC)
  • Diabetic ketoacidosis (adult)
  • Diabetic ketoacidosis (peds)
    • Cerebral edema in DKA
  • Diabetic foot infection
  • Diabetic peripheral neuropathy
• Hemochromatosis
• Iron toxicity
• Sepsis

Evaluation

Work Up

• Chemistry
• Serum osm
• Lactate
• Serum ketones
• CBC
• Also consider:
  • Blood cultures
  • Urinalysis/Urine culture
  • LFTs
  • Lipase
  • Troponin
  • CXR
  • ECG
  • Head CT

Diagnosis

• Glucose >600
• Osm >320
• Bicarb >15
• pH >7.3
• Serum ketones negative or mildly positive
• Neurologic abnormalities frequently present (coma in 25-50% of cases)

Management

1. Fluid replacement
   • Average fluid deficit is 8-12L
     • 50% should be replaced over the initial 12hr
     • May have to replace slower if patient has cardiac/renal impairment
     • Aggressiveness of fluid replacement must be weighed against the risk of cerebral edema, which increases with younger age
2. Hypokalemia
   • Must treat aggressively
   • Once adequate urinary output has been established K+ replacement should begin
3. Hyperglycemia
   • Do not start insulin until K > 3.3 and adequate urinary output has been established
4. Hypomagnesemia
   • Repletion will help correct hypokalemia
5. Hypophosphatemia
   • Routine correction unnecessary unless phos <1.0

Disposition

• Most patients require ICU admission

See Also

• Diabetes mellitus (main)
• Diabetic ketoacidosis
• Hypoglycemia