Hypokalemia & Hypomagnesia Case Study
HPI Dorothy Snow is a 45-year-old woman with a history of dilated cardiomyopathy who presents to the ED with a 3-day history of shortness of breath with mild-to-moderate exertion. She reports two to three-pillow orthopnea × 2 days and cough during sleep. Denies chest pain; positive occasional palpitations. Reports a 10-lb weight gain in the last week and an increase in her lower extremity edema. Five months ago, Mrs Snow was hospitalized brie?y with atypical chest pain and had persistent hypokalemia for which her metolazone 5 mg daily was discontinued. She subsequently developed signi?cant ?uid retention and her PCP restarted metolazone 5 mg po daily. 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.
Dilated cardiomyopathy—echo LVEF 25% (11 months ago)
ICD placement—primary prevention (3 weeks ago)
Pulmonary hypertension—secondary left heart disease
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.
Valsartan 160 mg po BID; Omeprazole 20 mg po daily; Carvedilol 25 mg po BID; Digoxin 0.25 mg po daily; Spironolactone 25mg po daily; Furosemide 80 mg po daily; Citalopram 20 mg po daily; Simvastatin 80 mg po daily; Insulin glargine 30 units SC Q 12 h; Insulin aspart 20 units SC TID with meals; Pregabalin 50 mg po BID; Metolazone 5 mg po daily; Loratadine 10 mg po daily; Tiotropium one puff daily; Fluticasone/salmeterol 500/50 one puff BID; Mometasone one spray each nostril daily; Meclizine 12.5 mg po BID; Magnesium oxide 400 mg po TID; Potassium chloride 80 mEq po BID; Levothyroxine 75 mcg po daily; ASA 81 mg po daily; Lorazepam 0.5 mg po TID; Feno?brate 48 mg po daily; Folic acid 1 mg po daily
Patient reports becoming short of breath for the past 3 days while walking up one ?ight of stairs or if she walks too quickly on a ?at surface. Previously she could walk two ?ights of stairs before becoming short of breath. She uses several pillows at night to sleep but does not report PND symptoms. She reports increased swelling in her lower extremities. States that she has not changed her diet, but did attend an all-day Super Bowl party the previous weekend and ate foods that were not part of her normal diet (e.g., chili, buffalo wings, veggies and dip, pizza). Denies ever having an ICD discharge
Gen – Appears older than her stated age; obese; mild dyspnea at rest
VS – P 112 bpm, RR 22, BP 110/60 mm Hg, T 35.8°C, Wt 192 lb (baseline weight 184 lb), Ht 5?5?, O 2 sat 88% room air
Skin – Skin warm, dry
HEENT – PERRLA; conjunctivae clear; moist mucous membranes; tongue midline
Neck/Lymph Nodes – Supple; JVP estimated at 13 cm; no carotid bruit; no lymphadenopathy; (+) thyroid nodules
Lungs – Bibasilar rales R > L; occasional wheezes
CV – Tachycardic; normal S 1 , S 2 ; +S 3 ; –S 4 ; 2/6 holosystolic murmur best heard at second left intercostal space
Abd – Obese; good bowel sounds; no bruits; no hepatosplenomegaly, (+) hepatojugular re?ux; no evidence of ascites
Genit/Rect – Deferred
Ext – No cyanosis; 3+ pitting edema to knees bilaterally; 2+ pulses bilaterally in upper and lower extremities
Back – No CVA tenderness
Neuro – Alert & oriented × 3; no focal de?cits; mild sensory de?cit in feet bilaterally; CN II–XII grossly intact
Na 133 mEq/L
Hgb 10.4 g/dL
Ca 8.3 mg/dL
Alb 3.0 g/dL
K 2.8 mEq/L
Mg 1.3 mEq/L
PT 14 s
Cl 93 mEq/L
WBC 4.5 × 10 3 /mm 3
Phos 3.1 mEg/L
CO 2 30 mEq/L
Plt 165 × 10 3 /mm 3
AST 100 IU/L
aPTT 21 s
BUN 17 mg/dL
BNP 1,027 pg/mL
ALT 110 IU/L
UA 6.8 mg/dL
SCr 0.8 mg/dL
Troponin 1 < 0.01 ng/mL
T. chol 144 mg/dL
Glu 143 mg/dL
CK 30 IU/L
Bilateral pulmonary edema; moderate R pleural effusion; small L pleural effusion; (+) cardiomegaly
Sinus tachycardia; LBBB; no evidence of acute ischemia
Admit to inpatient monitored bed.
1. Acute on chronic systolic heart failure
2. NYHA class III symptoms, ACC stage C
3. Volume overload
4. Electrolyte abnormalities
respond to the following questions:
1. Create a list of the patient’s drug therapy problems.
2. What information (signs, symptoms, and laboratory values) indicates the presence and severity of the electrolyte abnormalities?
3. What are the potential causes of the electrolyte disorders in this patient?
4. What additional information is needed to satisfactorily assess this patient’s electrolyte disorders?
5. What are the goals of pharmacotherapy in this patient?
6. What feasible pharmacotherapeutic alternatives are available for treatment of hypervolemia, hypokalemia, and hypomagnesemia in this patient?
7. Given the therapeutic alternatives outlined above, what is the most appropriate therapy for treatment of hypervolemia, hypokalemia, and hypomagnesemia in this patient?
8. What therapy changes should be made for the patient’s heart failure, hyperglycemia, and hypertriglyceridemia?
9. What clinical and laboratory parameters are necessary to evaluate the therapy for the desired therapeutic outcome and prevention of adverse effects?
10. What information should be provided to the patient to enhance adherence, ensure successful therapy, and minimize adverse effects?