Hyperkalemia (Serum K⁺ ≥5.5 mmol/l)

K⁺ ≥6.0 or ECG changes

Pseudohyperkalemia?

No further action

Treat accordingly and re-evaluate

Treat accordingly and re-evaluate^*

Decreased urinary K⁺ excretion (<40 mmol/d)

Decreased distal Na⁺ delivery

Reduced distal K⁺ secretion (GFR >20 mL/min)

Drugs

Amiloride
Spironolactone
Triamterene
Trimethoprim
Pentamidine
Eplerenone
Drospirenone
Calcineurin inhibitors

Other causes

Tubulointerstitial diseases
Urinary tract obstruction
PHA type I
PHA type II
Sickle cell disease
Renal transplant
SLE

Low aldosterone

Emergency therapy

K⁺ ≥6.0 or ECG changes

Pseudohypokalemia?

Yes

No

Yes

No

Yes

No

Urine electrolytes

Urine Na⁺ <25 mmol/L

TTKG

>8

<5

Emergency therapy

End

Yes

No

End

End

End

End

Reduced tubular flow

Advanced kidney failure (GFR ≤20 mL/min)

Reduced ECV

End

End

9α-Fludrocortisone

TTKG <8 (tubular resistance)

TTKG ≥8

End

Renin

High

Primary adrenal insufficiency
Isolated aldosterone deficiency
Heparin/LMW heparin
ACE-l/ARB
Ketoconazole

Low

Diabetes mellitus
Acute GN
Tubulointerstitial diseases
PHA type II
NSAIDs
β-Blockers

End

End

History, physical examination and basic laboratory tests

Evidence of increased K⁺ load

Evidence of transcellular shift:

Hypertonicity (e.g., mannitol)
Hyperglycemia
Succinylcholine
-aminocaproic acid
Digoxin
β-Blockers
Metabolic acidosis (nonorganic)
Arginine infusion
Hyperkalemic periodic paralysis
↓ Insulin
Exercise

Yes

No