Clinical - Renal/Urine/Electrolytes, Generic Clinical Sciences
Shift K+ from plasma back into the cell: intravenous glucose (25 to 50 g dextrose, or 1-2 amps D50) plus 5-10 U regular insulin will reduce serum potassium levels within 10 to 20 minutes, and the effects last 4 to 6 hours, hyperventilation , β-agonists . In the past, bicarbonate (1 mEq/kg, or 1-2 amps in a typical adult) was recommended, however keep in mind that bicarbonate rarely helps , and furthermore binds Ca++ , which may be counterproductive. Note that in the setting of liver tranplantation, prophylactic insulin and glucose has been suggested.
Increase renal excretion: diuretics (furosemide, 20-40 mg IV), resin exchange , dialysis , aldosterone agonists (fludrocortisone )
Acute Hyperkalemia Treatment
- Membrane Stabilization: CaCl2
- K+ Shift: glucose/insulin, induce alkalosis (bicarbonate, hyperventilation), β-agonists
- K+ Excretion: furosemide, resins, fludrocortisone, dialysis
Causes of acute hyperkalemia: drugs (succinylcholine, ACE/ARB’s, mannitol, spironolactone, digitalis, non-selective beta blockers) that cause decreased renal K+ excretion, reperfusion of an organ/vascular bed after ischemia (usually greater than 4 hours), adrenal inhibition or decreased aldosterone levels, transcellular shifts (intracellular to extracellular), often caused by acidosis, acute renal failure
Symptoms: mild elevation (6-7 mEq/L) can cause peaked T-waves on EKG tracing, 10-12 mEq/L can cause prolonged PR interval, widened QRS, VFib, Asystole. Clinical symptoms are muscle weakness and paralysis.