A nurse in a provider's office is monitoring blood electrolytes for four clients who take digoxin.
Which of the following electrolyte values increases a client's risk for digoxin toxicity?

Hypokalemia is a condition of low potassium levels in the blood, which can be caused by diuretics such as furosemide (Lasix) that increase the excretion of potassium in the urine. Potassium is an important electrolyte that helps regulate the function of nerves and muscles, including the heart.Low potassium levels can cause symptoms such as confusion, tremors, muscle cramps, and nausea, which are consistent with the patient’s presentation.

Choice B, renal failure, is wrong because furosemide is used to treat fluid retention and edema caused by kidney disease, not to cause it.Renal failure would also cause symptoms such as decreased urine output, swelling, fatigue, and shortness of breath, which are not mentioned in the question.

Choice C, hyperkalemia, is wrong because hyperkalemia is a condition of high potassium levels in the blood, which can be caused by kidney disease or certain medications that decrease the excretion of potassium in the urine.Hyperkalemia can cause symptoms such as weakness, irregular heartbeat, paralysis, and chest pain, which are different from the patient’s symptoms.

Choice D, heart failure, is wrong because furosemide is also used to treat fluid retention and edema caused by heart failure, not to cause it.Heart failure would also cause symptoms such as shortness of breath, coughing, fatigue, and rapid weight gain, which are not mentioned in the question.

Normal ranges for potassium levels in the blood are 3.5 to 5.0 milliequivalents per liter (mEq/L) for adults and 3.4 to 4.7 mEq/L for children.

A level below 3.5 mEq/L is considered hypokalemic and a level above 5.0 mEq/L is considered hyperkalemic.

Digoxin is a medication that can help the heart pump more blood and slow down the heart rate in certain conditions, such as heart failure and atrial fibrillation.However, digoxin has a narrow therapeutic range, which means that too much or too little of it can be harmful.The therapeutic range of digoxin levels in the blood is 0.5-2 ng/mL, and the toxic level is >2.4 ng/mL.Digoxin should be held if the resting apical pulse of an infant is <90 bpm, an older child is <70 bpm, or an adult is <60 bpm.A pulse of 48/min in an adult is too low and could indicate digoxin toxicity, which can cause life-threatening arrhythmias. Therefore, the nurse should withhold the dose and notify the health care provider immediately.

Choice B is wrong because notifying the health care provider and monitoring the patient’s vital signs are not enough.

The nurse should also withhold the dose to prevent further exposure to digoxin.

Choice C is wrong because rechecking the pulse, making sure to count for 1 full minute, is not necessary.The nurse should already have counted the pulse for 1 full minute before administering digoxin, as per standard procedure.

Choice D is wrong because administering the dose could worsen the patient’s condition and increase the risk of digoxin toxicity and arrhythmias.