Hyperkalemia

Hyperkalemia is a common clinical problem, caused by the inability to excrete potassium due to renal impairment or drugs. The therapy is ultimately to increase potassium excretion, either via medications or by dialysis. The first cause of action however, is to shift the potassium into the cells.

General

• measure twice, high Potassium can be caused by hemolytic blood or prolonged tourniquet use/muscular activity when drawing blood
• large IV access
  • you might need a dialysis catheter in the future
  • consider increased DOAC-levels in renal failure, in case you want to insert a central catheter
• monitoring
  • ECG and NIBP
• medication history
  • Potassium-sparing diuretics (spironolactone, eplerenone, amiloride, triamterene)
  • several other medications might need adjustment based on current renal function

Stratification

Different strategies exist to assess the severity of hyperkalemia, using combinations of potassium levels, cardiac abnormalities and comorbidities. A non-complete combination of different sources follows

Management

Membrane stabilization

• calcium gluconate
  • 1000 mg (10 ml of 10 % solution)
• or 500 mg — 1000 mg calcium chloride i.v. over two to three minutes

Shift into cells

• Salbutamol nebulized (2.5 mg, max 20 mg/day)
  • Dosing varies depending on source
  • Careful in coronary disease
• Glucose-Insulin
  • 10 to 20 units regular insulin followed by 25 g of glucose (e.g. 50 ml of 50%)
    • only give glucose if serum glucose < 250 mg/dl
  • if removal of excess potassium is delayed, continuous infusion of insulin and glucose can be considered
• Sodium bicarbonate
  • don’t give hypertonic bicarbonate
    • the hypertonic solution causes potassium to shift out of the cells
  • isotonic bicarbonate should be considered in metabolic acidosis

Remove potassium from the body

• Hemodialysis in end-stage renal disease or severe renal impairment
• Diuretics depending on renal function (40 mg to 120 mg furosemide)
  • replace fluid losses, several options are available. These options should also be considered in hypovolemic patients
    • Isotonic bicarbonate is preferred in metabolic acidosis
      • Bicarbonate can precipitate if mixed with solutions containing calcium, magnesium or phosphate!
    • Isotonic saline
      • recommended by UpToDate without discussion of lactated ringer vs normal saline
    • Lactated ringers
      • article on lr vs ns on emcrit
• Cation exchangers
  • Patiromer
    • not evaluated with acute hyperkalemia
    • interactions with other drugs, including ciproflocaxin, thyroxine, metformin
  • Zirconium cyclosilicate
    • not evaluated with acute hyperkalemia
  • sodium polystyrene sulfonate
    • appears to not be more effective than laxative therapy
    • severe side effects, including intestinal necrosis

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