CLINICAL QUERIES: What causes sudden hypokalemia?
Judy Sweeney RN, MSN

$3.95
Nursing2015
April 2005 
Volume 35  Number 4
Pages 12 - 12
 
  PDF Version Available!

ABSTRACT
Outline

  • SELECTED REFERENCES

    My patient, admitted with worsening heart failure, was receiving digoxin and furosemide. As his respiratory acidosis and volume overload resolved, his serum potassium dropped from 4.2 to 3 mEq/liter in 24 hours. Why did he become hypokalemic so fast?—T.K., MASS.

    Judy Sweeney, RN, MSN, replies: Normally, extracellular levels of potassium are relatively small (3.5 to 5 mEq/liter) compared with intracellular levels (about 150 mEq/liter), so the serum lab value for potassium constitutes less than 2% of the total body content.

    Although your patient's serum potassium level was initially normal, remember that changes in pH and hydrogen ion concentration cause potassium to shift between the extracellular and intracellular spaces. Because of these factors, acidosis causes a relative excess of extracellular potassium.

    When your patient was experiencing respiratory acidosis, potassium shifted out of cells into the extracellular fluid as it exchanged with hydrogen ions. Moving hydrogen ions into cells helped correct the acidosis by increasing pH. When the acidosis resolved and the extracellular pH returned to normal, some potassium returned to the cells, creating a relative deficiency of potassium in extracellular fluid. This, coupled with renal potassium losses from furosemide-induced diuresis, helps to explain your patient's hypokalemia.

    Other possible causes of hypokalemia include:

    * increased aldosterone production, which enhances potassium excretion in the urine

    * vomiting or diarrhea, resulting in volume depletion and metabolic alkalosis; both promote urinary excretion of potassium.

    Signs and symptoms of hypokalemia include fatigue, myalgia, and muscle weakness. More severe hypokalemia can cause paralysis, respiratory failure, cardiac arrhythmias, and hypotension. Early ECG changes include T-wave flattening or inversion, prominent U waves, and ST-segment ...

Purchase Now !

To purchase this item, follow the instructions below. If you’re not already logged in, be sure to enter your login information below to ensure that your item is saved to your File Drawer after you purchase it.

Not a member? Join now for Free!


Cost:$3.95
1) If you're not already logged in, enter your information below to save this item in your File Drawer for future viewing.

User name:


Password


Forgot your user name or password?
2)  If you have a coupon or promotional code, enter it
here.(If not, just click Continue.


Digital Coupon: (optional)

3)  Click Continue to go to the next screen, where
you'll enter your payment details.






jQuery UI Accordion - Default functionality

For life-long learning and continuing professional development, come to Lippincott's NursingCenter.

Nursing Jobs Plus
Featured Jobs
Recommended CE Articles

Blunt Chest Trauma
Journal of Trauma Nursing, November/December 2014
Expires: 12/31/2016 CE:2 $21.95


The School Age Child with Congenital Heart Disease
MCN, The American Journal of Maternal/Child Nursing, January/February 2015
Expires: 2/28/2017 CE:2.5 $24.95


Understanding multiple myeloma
Nursing Made Incredibly Easy!, January/February 2015
Expires: 2/28/2017 CE:2 $21.95


More CE Articles

Subscribe to Recommended CE

Recommended Nursing Articles

Comprehensive Care: Looking Beyond the Presenting Problem
Journal of Christian Nursing, January/March 2015
Free access will expire on March 2, 2015.


Pain and Alzheimer dementia: A largely unrecognized problem
Nursing Made Incredibly Easy!, January/February 2015
Free access will expire on February 16, 2015.


Glycemic control in hospitalized patients
Nursing2015 Critical Care, January 2015
Free access will expire on February 16, 2015.


More Recommended Articles

Subscribe to Recommended Articles

Evidence Based Practice Skin Care Network NursingCenter Quick Links What’s Trending Events