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?

ACE inhibitors are a type of medication used to treat high blood pressure and heart failure. They work by blocking the production of a hormone called angiotensin II, which narrows the blood vessels and increases blood pressure.By preventing this hormone from acting, ACE inhibitors lower blood pressure and reduce the workload on the heart. One of the most common side effects of ACE inhibitors is a dry cough, which occurs in 12–19% of people who take them. The cough is caused by the accumulation of a substance called bradykinin, which is normally broken down by angiotensin-converting enzyme (ACE).When ACE is inhibited, bradykinin levels increase and cause irritation and inflammation in the airways.

Choice A is wrong because decreased white blood cells are not a common side effect of ACE inhibitors.

However, some people may develop a condition called neutropenia, which is a low level of a type of white blood cell called neutrophils.This can increase the risk of infections and may require stopping the medication.

Choice B is wrong because swelling of the face and lips is not a common side effect of ACE inhibitors.

However, some people may develop a rare but serious allergic reaction called angioedema, which is a swelling of the deeper layers of the skin and mucous membranes.

This can affect the face, lips, tongue, throat, or other parts of the body and can cause difficulty breathing or swallowing.Angioedema can be life-threatening and requires immediate medical attention.

Choice D is wrong because renal failure is not a common side effect of ACE inhibitors.

However, some people may experience a decrease in kidney function or an increase in blood levels of creatinine, which is a waste product filtered by the kidneys.

Digibind is the trade name forantidigoxin, which is an antibody made up of anti-digoxin immunoglobulin fragments.It is thespecific antidoteto digoxin toxicity, which can occur even when the serum digoxin concentration is within the therapeutic range.Digoxin toxicity causes anorexia, nausea, vomiting, neurological symptoms and arrhythmias.

Choice A, Protamine sulfate, is wrong because it is the antidote for heparin overdose, not digoxin toxicity.

Protamine sulfate reverses the anticoagulant effect of heparin by binding to it and forming a stable complex.

Choice B, Acetylcysteine, is wrong because it is the antidote for acetaminophen overdose, not digoxin toxicity.

Acetylcysteine replenishes glutathione, which is depleted by acetaminophen metabolites that cause hepatotoxicity.

Choice D, Vitamin K, is wrong because it is the antidote for warfarin overdose, not digoxin toxicity.

Vitamin K restores the synthesis of clotting factors that are inhibited by warfarin.

Normal ranges for serum digoxin concentration are 0.6 to 1.2 nanomol/L (0.5 to 0.9 nanograms/mL) for heart failure and unknown for atrial fibrillation without heart failure.

Normal ranges for serum potassium level are 3.5 to 5.0 mmol/L and for serum magnesium level are 0.7 to 1.0 mmol/L.