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After completing this case study, the reader should be able to:
Analyze a patient case history and identify potential causes of electrolyte disorders.
Select the appropriate route of administration and dose of electrolyte replacement therapy specific for a patient.
Develop a monitoring plan for efficacy and toxicity in patients receiving electrolyte replacement therapy.
Outline a patient education plan for a patient receiving electrolyte replacement supplements.
Dorothy Snow is a 45-year-old woman with a history of nonischemic cardiomyopathy who presents to the ED with a 3-day history of shortness of breath with mild to moderate exertion. She reports three-pillow orthopnea × 2 days and cough during sleep. Denies chest pain; occasional palpitations. She has some stomach discomfort that she notices after taking her potassium supplement. She reports a 10-lb weight gain in the past week and an increase in her lower extremity edema.
Two months ago, Mrs Snow was hospitalized briefly with atypical chest pain and had persistent hypokalemia for which her metolazone 5 mg daily was discontinued. Approximately 1 month ago, shortly after Thanksgiving, she subsequently developed significant fluid retention and her PCP restarted metolazone 5 mg PO MWF. About 2 weeks ago, she had an ED visit and her potassium was 7.2 mEq/L (hemolyzed sample). The potassium level was repeated with a result of 5.5 mEq/L. At that time, her potassium supplement dose was reduced from 80 mEq PO QID to 80 mEq PO BID.
PMH (Per Patient Report and Medical Records)
Nonischemic cardiomyopathy—echo LVEF 25% (11 months ago)
ICD placement 2 months ago
Type 2 DM with peripheral neuropathy
Both parents are deceased.
Lives with husband. No alcohol use. Former smoker—quit 8 years ago. No illicit drugs.
Candesartan 32 mg PO daily
Omeprazole 20 mg PO daily
Spironolactone 25 mg PO daily
Citalopram 20 mg PO daily
Atorvastatin 20 mg PO daily