Management of potassium

Hypo and hyperkalemia Posted by Ahmad Azizov on October 04, 2020

Management of potassium 

Hypo or hyperkalemia are common problems in the management of emergency department patients as well as hospital inpatients. It is important to recognize this problem early and manage it appropriately. 

Picture 1. Basic metabolic panel includes the values of a few basic electrolytes and other metabolic markers

Hypokalemia 

  • Patients with CAD, CHF or other heart problems should be kept at 4.0
  • It is far easier to correct K levels when the potassium levels aren't very depleted
    • If potassium is 3.0-4.0 = Mild hypokalemia 
      • 10mEq K infusion will bump the K up by 0.1 
    • If potassium is 2.5-3.0 = Moderate hypokalemia 
      •  15mEq K infusion will bump the K up by 0.1
    • If potassium is 2.0-2.5 = Severe hypokalemia 
      • 20mEq K infusion will bump the K up by 0.1 
    • Can get a basic metabolic panel, but don't have to
  • Routes 
    • Peripheral IV KCl
      • The rate of infusion has to be <=10mEq/hr or the patient will have a burning sensation 
    • Central IV KCl
      • Rate has to be <=20mEq/hr
      • Can be lethal if faster than 20mEq/hr
    • PO KCl elixir 
      • 20 or 40mEq
      • Taste is not tolerable to some 
    • PO KCl tablet 
      • 20 or 40mEQ
  • Things to note 
    • High K is above 5.5 and we are targeting 4.0 when a patient is hypokalemic= almost impossible to overshoot by correcting hyperkalemia 
    • Need to be cautious in patients with chronic kidney disease
    • Magnesium infusion 
    • Keep potassium losses in mind and compensate for them
      • Furosemide 
      • NG suction 
      • Diarrhea

Hyperkalemia 

  • Get an ECG  
    • ECG changes will occur if there is a rapid increase resulting in hyperkalemia
    • Changes 
      • Serum K>5.5
        • Peaked T waves
        • T waves almost as tall as QRS
        • ECG computer may read the heart rate as double 
      • Later changes 
        • Widened PR 
        • Wide P wave  
        • Heart blocks 
        • Bradycardia 
        • Prolonged QRS
        • Asystole, Vfib, PEA if severe
  • Change in K value over time is very important to note
    • Patients on dialysis and who miss dialysis can have high serum K but because it builds up chronically = no ECG changes
  • Management 
    • Get an ECG and assess for changes
    • Stabilize 
      • IV Calcium gluconate (protects myocytes)
      • Does not change actual serum potassium levels 
      • A few mins in duration 
    • Temporize 
      • 10 units IV insulin is given with D50 (prevent hypoglycemia)
      • Takes 30-60 mins to take effect
      • Lasts up to 4 hours 
    • Eliminate 
      • Furosemide (if no kidney problem exists)
      • Kayexalate
        • Binds to cations and exchanges K+ with Na+, eliminating K through the stool 
        • Take at least 2 hours to work 
      • Dialysis (if severe)
    • ECG changes 
      • If present, call renal for dialysis 
      • If not present, go through the steps above

All information provided on this website is for educational purposes and does not constitute any medical advice. Please speak to you doctor before changing your diet, activity or medications. 


Written by
Ahmad Azizov Member since April 2020
Interested in Vascular surgery resident at Western U

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