An elderly woman presents with 4 days of generalized weakness and fatigue secondary to diarrhea. On examination, she appears dehydrated. During your workup, you find that she is in acute renal failure and is suffering from hyperkalemia, with a serum potassium of 6.5 mEq/L. Her ECG shows mild peaked T waves. During discussion with the admitting physician, you are asked to give the patient sodium polystyrene. You seem to recall some controversy regarding this treatment and wonder if it is really indicated for this patient.
Your next patient is a 24-year-old woman with diarrhea and vomiting. During your workup, you find that she has hypokalemia, with a potassium level of 2.2 mEq/L, an ECG with a prolonged QT interval, and a serum magnesium of 1.9 mEq/L. The patient’s internist recommends treatment with an antiemetic, oral potassium, and discharge home. You wonder if this is the best management plan.
Your third patient is a dialysis-dependent 56-year-old man who presents with shortness of breath and weakness. His serum potassium is 6.9 mEq/L, and there is evidence of fluid overload on the chest radiograph. You contact renal to arrange emergent dialysis and they recommend that you administer a “new” potassium-binding agent and discharge the patient for his regularly scheduled dialysis appointment later in the day. You wonder what these new agents are and whether best practice has recently changed without your being aware of it.
Potassium disorders are common and potentially deadly, which makes early recognition and treatment fundamental to quality emergency care. The symptoms that a patient may experience with these disorders are typically vague and difficult to distinguish. The emergency clinician must have a heightened index of suspicion and a low threshold for testing and treating. Recent literature has questioned several age-old practices and has challenged the emergency clinician to assess new practice paradigms, including the routine ordering of serum magnesium levels in patients with hypokalemia, redrawing potassium levels in a hemolyzed sample, proper blood-drawing techniques, and the utility of sodium polystyrene sulfonate and bicarbonate in the treatment of acute hyperkalemia. This issue of Emergency Medicine Practice provides a systematic review of the newest evidence regarding the pathophysiology, diagnosis, and management of potassium-related emergencies.
A MEDLINE® search for randomized controlled trials since 2010 was conducted using the search terms hyperkalemia and hypokalemia. MEDLINE® was also queried using the terms hyperkalemia and hypokalemia and therapy or treatment in order to identify studies that have not yet reached the randomized controlled trial phase. A total of 281 articles were identified and reviewed, with 118 being for hyperkalemia and 163 articles for hypokalemia. The literature reviewed had numerous large retrospective studies but very few randomized controlled trials for either hyperkalemia or hypokalemia. Moreover, very few articles reviewed dealt with new management strategies of these disease processes. The National Guideline Clearinghouse (www.guideline.gov) was searched and no recommendations for the treatment of hyper-kalemia or hypokalemia were found. The Cochrane Database of Systematic Reviews was also queried. No reviews have been published for hypokalemia; a review was published in 2009 for hyperkalemia, but it has not been updated.
Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.
To help the reader judge the strength of each reference, pertinent information about the study is included in bold type following the reference, where available.
To continue reading, please log in or purchase access.
John Ashurst, DO, MSc; Shane R. Sergent, DO; Benjamin J. Wagner, DO
November 1, 2016
December 1, 2019
4 AMA PRA Category 1 Credits™, 4 ACEP Category I Credits, 4 AAFP Prescribed Credits, 4 AOA Category 2-A or 2-B Credits. Specialty CME Credits: Included as part of the 4 credits, this CME activity is eligible for 2 Pharmacology CME credits
Upon completion of this article, you should be able to:
Date of Original Release: November 1, 2016. Date of most recent review: October 10, 2016. Termination date: November 1, 2019.
Accreditation: EB Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians. This activity has been planned and implemented in accordance with the accreditation requirements and policies of the ACCME.
Credit Designation: EB Medicine designates this enduring material for a maximum of 4 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
ACEP Accreditation: Emergency Medicine Practice is approved by the American College of Emergency Physicians for 48 hours of ACEP Category I credit per annual subscription.
AAFP Accreditation: This Medical Journal activity, Emergency Medicine Practice, has been reviewed and is acceptable for up to 48 Prescribed credits by the American Academy of Family Physicians per year. AAFP accreditation begins July 1, 2016. Term of approval is for one year from this date. Each issue is approved for 4 Prescribed credits. Credit may be claimed for one year from the date of each issue. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
AOA Accreditation: Emergency Medicine Practice is eligible for up to 48 American Osteopathic Association Category 2-A or 2-B credit hours per year.
ABIM Accreditation: Successful completion of this CME activity, which includes participation in the evaluation component, enables the participant to earn up to 4 MOC points in the American Board of Internal Medicine's (ABIM) Maintenance of Certification (MOC) program. Participants will earn MOC points equivalent to the amount of CME credits claimed for the activity. It is the CME activity provider's responsibility to submit participant completion information to ACCME for the purpose of granting ABIM MOC credit.
Specialty CME: Included as part of the 4 credits, this CME activity is eligible for 2 Pharmacology CME credits, subject to your state and institutional approval.
Needs Assessment: The need for this educational activity was determined by a survey of medical staff, including the editorial board of this publication; review of morbidity and mortality data from the CDC, AHA, NCHS, and ACEP; and evaluation of prior activities for emergency physicians.
Target Audience: This enduring material is designed for emergency medicine physicians, physician assistants, nurse practitioners, and residents.
Goals: Upon completion of this activity, you should be able to: (1) demonstrate medical decision-making based on the strongest clinical evidence; (2) cost-effectively diagnose and treat the most critical presentations; and (3) describe the most common medicolegal pitfalls for each topic covered.
Discussion of Investigational Information: As part of the journal, faculty may be presenting investigational information about pharmaceutical products that is outside Food and Drug Administration–approved labeling. Information presented as part of this activity is intended solely as continuing medical education and is not intended to promote off-label use of any pharmaceutical product.
Faculty Disclosure: It is the policy of EB Medicine to ensure objectivity, balance, independence, transparency, and scientific rigor in all CME-sponsored educational activities. All faculty participating in the planning or implementation of a sponsored activity are expected to disclose to the audience any relevant financial relationships and to assist in resolving any conflict of interest that may arise from the relationship. In compliance with all ACCME Essentials, Standards, and Guidelines, all faculty for this CME activity were asked to complete a full disclosure statement. The information received is as follows: Dr. Ashurst, Dr. Sergent, Dr. Wagner, Dr. Pfennig, Dr. Slovis, Dr. Damilini, Dr. Toscano, Dr. Jagoda, and their related parties report no significant financial interest or other relationship with the manufacturer(s) of any commercial product(s) discussed in this educational presentation.
Commercial Support: This issue of Emergency Medicine Practice did not receive any commercial support.
Earning Credit: Two Convenient Methods: (1) Go online to www.ebmedicine.net/CME and click on the title of the article. (2) Mail or fax the CME Answer And Evaluation Form (included with your June and December issues) to EB Medicine.
Hardware/Software Requirements: You will need a Macintosh or PC to access the online archived articles and CME testing.
Additional Policies: For additional policies, including our statement of conflict of interest, source of funding, statement of informed consent, and statement of human and animal rights, visit www.ebmedicine.net/policies.