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. 

1. What are possible causes of a low potassium level?
2. What action should the nurse take in relation to the serum potassium level?
3. 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%

1. What is your interpretation of this arterial blood gas sample?
2. Explain the high potassium in this patient.
3. Calculate the patient’s anion gap:
4. What is the interpretation of this anion gap?