endocrine / metabolic

Severe Hyperosmolar Hyperglycemic Crisis

Profound dehydration and hyperosmolality with severe hyperglycemia: separate isolated HHS from mixed DKA/HHS, restore circulation, sequence potassium and insulin correctly, and avoid rapid osmotic shifts.

CLINICAL ALGORITHMMedically Verified (2026-09-15)

Hyperglycemic crisis: distinguish DKA, HHS and overlap, then sequence potassium, fluids and insulin safely

Level: Controlled React algorithm

Visual bedside algorithm

Hyperglycemic crisis: distinguish DKA, HHS and overlap, then sequence potassium, fluids and insulin safely

Step 1 · Assess / decide

Define the phenotype

Glucose + beta-hydroxybutyrate
Venous pH/bicarbonate + electrolytes
Serum osmolality + mental status
Classify DKA, isolated HHS or mixed DKA/HHS

Step 2 · Treat

Fluids + potassium first

Restore volume with individualized isotonic/balanced crystalloid
Check potassium before insulin
If K+ <3.5 mmol/L: replace potassium and delay insulin

Step 3 · Treat

Insulin + dextrose

DKA/mixed DKA-HHS: DKA insulin strategy
Isolated HHS: lower-dose insulin after initial fluids
Add dextrose as glucose falls so insulin can continue until the metabolic crisis resolves
Euglycemic DKA still requires insulin to stop ketogenesis

Step 4 · Escalate / reassess

Reassess safely

DKA: ketones + pH/bicarbonate, not glucose alone
HHS: cognition, osmolality, sodium and urine output
Avoid rapid tonicity/osmolality shifts
Find and treat infection, ischemia, medication interruption or other trigger

Bedside bottom line

Never start insulin before correcting severe hypokalemia, and never declare resolution from a normalized glucose value alone.

Figure: Hyperglycemic crisis: distinguish DKA, HHS and overlap, then sequence potassium, fluids and insulin safely. This action-focused visual summarizes the linked Clinical Problem; the full problem text, evidence references and local policy remain the source of truth.(Action pathway — use the full evidence-linked problem and local protocol for clinical decisions)

Confirm HHS vs mixed DKA/HHS

Measure glucose, electrolytes, venous pH/bicarbonate, beta-hydroxybutyrate and serum osmolality. HHS has severe hyperglycemia/hyperosmolality and dehydration without major ketoacidosis; clinically important ketonemia/acidosis means mixed DKA/HHS and changes the insulin strategy.

Fluids first

Restore intravascular volume with isotonic saline or balanced crystalloid, individualized for age, heart failure and kidney disease. Reassess blood pressure, perfusion, urine output, sodium and osmolality frequently rather than giving a fixed unmonitored volume.

Potassium before insulin

Check potassium before insulin. If K+ is <3.5 mmol/L, replace potassium and delay insulin until K+ is safely above that threshold. Anticipate potassium decline once insulin and volume restoration begin.

Insulin strategy

Avoid rapid osmotic correction

Resolution / reassessment

Caution

Do not start insulin before correcting severe hypokalemia, and do not chase the glucose number alone: the neurologic risk in HHS is driven by the rate of change in tonicity/osmolality.

Direct evidence for this problem

1 source

guideline•2024

Hyperglycemic Crises in Adults With Diabetes: A Consensus Report ↗

Current adult consensus criteria and treatment for HHS, DKA and mixed DKA/HHS.

Evidence status

Review metadata not yet recorded.

Status, review dates and guideline versions appear here once editorial metadata is authored for this content.

Actionable Clinical Workflows (4)

Step-by-step ICU Processes

Acute Severe Metabolic Acidosis Evaluation

From primary disorder confirmation and Anion Gap calculation to Winter's compensation, delta ratio, and targeted source control.

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Metabolic Acidosis

From confirming the acid-base disorder to the anion-gap differential.

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Altered Consciousness

From securing the basics to categorizing structural, toxic-metabolic, infectious, and seizure-related causes.

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Hyperosmolar Hyperglycemic State: First 6 Hours

Confirm HHS vs mixed DKA/HHS → restore volume → potassium-safe insulin → controlled osmolality correction.

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Deep-Dive Topic Destinations (2)

Reference Knowledge

Hyperosmolar Hyperglycemic State (HHS)endocrine-metabolic

ICU recognition and treatment of severe hyperglycemia, hyperosmolality and dehydration with careful fluid, potassium and insulin sequencing.

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Diabetic Ketoacidosis (DKA)endocrine-metabolic

Pathophysiology, SGLT2i euglycemic DKA, balanced fluid resuscitation, potassium-before-insulin safety rules, dextrose addition kinetics, and subcutaneous transition.

Explore Topic →