Case Study, Chapter 13, Fluid and Electrolytes: Balance and Disturbance
1. Mrs. Dean is 75-year-old woman admitted to the hospital for a small bowel obstruction. Her medical history includes hypertension. Mrs. Dean is NPO. She has a nasogastric (NG) tube to low continuous suction. She has an IV of 0.9% NS at 83 mL/hr. Current medications include furosemide 20 mg daily and hydromorphone 0.2 mg every 4 hours, as needed for pain. The morning electrolytes reveal serum potassium of 3.2 mEq/L.
- What are possible causes of a low potassium level?
- What action should the nurse take in relation to the serum potassium level?
- What clinical manifestations might the nurse assess in Mrs. Dean?
2. Conrad Jackson is a 28-year-old man who presents to the emergency department with severe fatigue and dehydration secondary to a 4-day history of vomiting. During the interview, he describes attending a family reunion and states that perhaps he “ate something bad.” Upon admission his vital signs are a temperature of 102.7°F, heart rate of 116 bpm, respiratory rate of 18 breaths/min, and blood pressure of 86/54 mm Hg. The nurse also notes the patient has dry mucous membranes and tenting of skin. The physician orders an IV to be started with 0.45% normal saline, and orders a serum electrolytes and an arterial blood gas.
The following results are returned from the laboratory:
Sodium (Na+) 150
Potassium (K+) 5.5
Chloride (Cl¯) 110
BUN 42
Creatinine 0.8
Glucose 86
pH 7.32
PaCO2 35
HCO3¯ 20
PaO2 90
O2 Sat 98%
- What is your interpretation of this arterial blood gas sample?
- Explain the high potassium in this patient.
- Calculate the patient’s anion gap:
- What is the interpretation of this anion gap?