Hyperosmolar Syndrome

Hyperosmolar Syndrome is a topic covered in the 5-Minute Emergency Consult.

To view the entire topic, please or purchase a subscription.

Emergency Central is a collection of disease, drug, and test information including 5-Minute Emergency Medicine Consult, Davis’s Drug, McGraw-Hill Medical’s Diagnosaurus®, Pocket Guide to Diagnostic Tests, and MEDLINE Journals created for emergency medicine professionals. Explore these free sample topics:

Emergency Central

-- The first section of this topic is shown below --



  • Results from a relative insulin deficiency in the undiagnosed or untreated diabetic
  • Sustained hyperglycemia creates an osmotic diuresis and dehydration:
    • Extracellular space maintained by the osmotic gradient at the expense of the intracellular space
    • Eventually profound intracellular dehydration occurs.
  • Total body deficits of H2O, Na+, Cl, K, PO4, Ca2+, and Mg2+
  • In contrast to diabetic ketoacidosis (DKA), severe ketoacidosis does not occur:
    • Circulating insulin levels are higher.
    • The elevation of insulin counter-regulatory hormones is less marked.
    • The hyperosmolar state itself inhibits lipolysis (the release of free fatty acids) and subsequent generation of keto acids

Geriatric Considerations
  • Most commonly seen in elderly type II diabetics who experience a stressful illness that precipitates worsening hyperglycemia and reduced renal function
  • In the elderly, 30–40% of cases are associated with the initial presentation of diabetes.

Pediatric Considerations
Hyperosmolar hyperglycemic states (HHS) rare in pediatric patients


  • Hyperosmolar state precipitated by factors that:
    • Impair peripheral insulin action
    • Increase endogenous or exogenous glucose
    • Decrease patient's ability to replace fluid loss
  • Infection is the most common precipitating factor in 32–60% of cases.
  • Other precipitating causes include:
    • Inadequate diabetes therapy
    • Medication omission
    • Diet indiscretion
    • Infections
    • Pneumonia
    • UTI
    • Sepsis
    • Medications/drugs
    • Diuretics
    • β-blockers
    • Calcium channel blockers
    • Phenytoin
    • Cimetidine
    • Amphetamines
    • Ethanol
    • Myocardial infarction
    • Stroke
    • Renal failure
    • Heat stroke
    • Pancreatitis
    • Intestinal obstruction
    • Endocrine disorders
    • Burns
    • Heat stroke

-- To view the remaining sections of this topic, please or purchase a subscription --