Hyperkalemia ICD-10-CM codes

Hyperkalemia is coded E87.5, with no additional characters for severity. As with all electrolyte codes, the provider must document hyperkalemia or elevated potassium; a laboratory value alone is not codable. Pseudohyperkalemia from a hemolyzed specimen is not hyperkalemia and should not be coded to E87.5.

Most hyperkalemia is secondary to another condition, and that condition is coded as well. Chronic kidney disease is reported with its stage (N18.4, N18.5, or N18.6 for end stage renal disease with Z99.2 for dialysis dependence), and acute kidney injury with N17.9 or a more specific N17 code. Acute metabolic acidosis is E87.21. For drug-related hyperkalemia, sequence E87.5 first and add the adverse effect: T50.0X5A for potassium-sparing diuretics and mineralocorticoid antagonists such as spironolactone, and T46.4X5A for ACE inhibitors.

Sequencing follows the circumstances of admission. A patient admitted for emergency treatment of hyperkalemia has E87.5 as principal with the kidney disease secondary; a patient admitted for acute kidney injury with hyperkalemia found on labs has N17.9 first. Cardiac conduction changes attributed to hyperkalemia, such as a documented arrhythmia, are coded in addition from I44 to I49.